ARDS is a severe, often life-threatening of several systemic disorders and direct injury to the lungs. It is major component of multiple organ dysfunction syndrome (MODS) and a manifestation of the systemic inflammatory response syndrome (SIRS) that can develop in trauma patients. 

Causes: 

ARDS can be precipitated by various serious medical and surgical conditions such as pneumonia, aspiration of gastric contents, sepsis, severe trauma with shock, and multiple transfusions. 

Symptoms: 

ARDS is a syndrome of acute pulmonary inflammation and resultant increased capillary endothelial permeability. ARDS of different aetiologies is characterized by local inflammatory response. The formation of fibrin-rich exudates (hyaline membranes) in the lumen of lung alveoli is a morphological hallmark of ARDS. 

Mechanisms to Pathology: 

Intra-alveolar fibrin deposition occurring as a result of damage to the capillary endothelium or the alveolar epithelium significantly contributes to the pathologenesis of ARDS by decreasing surfactant activity, whic

h favors alveolar collapse, and by decreasing alveolar fluid clearance. 

Tissue Factor upregulation: 

Tissue Factor (TF) is a 47 kDa transmembrane glycoprotein which enalbes cells to initiate the coagulation cascade. The extracellular N-terminal domain of TF contains functional sites for factor VIIa (FVIIa) binding (e.g., Lys20). The coagulation cascade is triggered when TF binds to FVIIa.  

An etiologic role for TF in spesis indued respiratory and fenal falure have been demonstrated and blockage of TF effectively preserves both pulmonary and renal function (Ezban (US2004/0033200A1). 

Broncoalveolar lavage fluid (BALF) from ARDS pateints have been shown to have procoagulant activity that is tissue factor dependent and is more profound during the first 3 days following the clinical diagnosis of ARDS. TF which initiates coagulation in vivo is present only in minimal amount in the circulating blood under physiological conditions. However, several inflammatory mediators, including complement anaphylatoxins and cytokines, up-regulate TF expression in circulating leukocytes and thereby increase the thrombogenic activity of the blood. The inflammatory mediators also spill over into the general circulation. Lambris (US12/669695)

Complement upregulation: In vitro, C5a and the terminal complex of complement, C5b-9 induce tissue factdor expression on endothelial cells and monocytes, and assembly of C5b-9 on the surface of platelets has been shown to stimulate prothombinase activity. Goldenberg (US2006/0140936A1) disclose improved therapeutics for treating sepsis by providing multispecific antagonists that target two or more of coagulation factors, proinflammatory cytokines and complement activation products. In one embodoment, Goldenberg teaches a multispecific antagonist to TF and to a complement factors, specially C3, C5, C3a, or C5a and thrombin. 

Treatment:

Complement and Cytokine inhibitors:

–Inhibition of C3 and C3b: Bansal (US2008/023313A1) teaches methods of inhibiting C3b dependent complement activation by limiting C3 cleavage as with an anti-C3 antibody as being useful for the treatment of a pulmonary condition such as acute respiratory distress syndrome. 

Lambris (US12/669695) discloses a method for treating acute respiratory distress syndrome (ARDS) by administering a complement inhibitor  inhibitor such as compstatin. Similarly, Lambris in WO 99/13899 teaches complement inhibiting compounds such as compstatin which are useful in treating disorders such as ARDS. 

Francois (US2010/0166862A1) teaches a method of treating a complement mediated disorder by adminsitering a complement inhibitor such as an inhibitor of C3 which can be a compstatin analog. Among the numerous complement disorders listed by Francois is adult respiratory distress syndrome. 

–Inhibition of C5a binding to C5aR: Lambris (US12/669695) teaches that inhibition of C5a binding to C5aR is effective to reduce tissue factor expression in nuetrophils present in alveolar fluid of ARDS patients which in turn reduces the pro-coagulant activity of aveolar fluid. A number of C5aR inhibitor are known in the art. C5a activity may be inhibited by pventing formation of C5a as by inhibiting the cleavage of C5 by C5-convertase. Eculizumab, for example, is an anti-C5 anitobdy that binds to C5 and prevents its cleavge into C5a and C5b. Formation of C5a may also be inhibited indirectly by inhibting the clevage of C3 which yields C3b and C3a. A C3 inhibitor such as compstatin, for example, can be used to inhibit C3. 

Hagen (J. of Surgical Research 46, 195-199 (1989) also showed that anti-human C5 antibodies resulted in attenuation of septic shock and pulmonary edema in a ARDS primate model.

Maxwell (US2006/0217530A10 discloses cyclic petidic and peptidomimetic antagnosts of C5a receptors which are are useful in the treatment of a variety of inflammatory conditions such as ARDS.  

Inhibition of TNF-alpha:Lambris (US12/669695) discloses that inhibition of TNF lapha is effective to reduce or prevent tissue factor expression in nuetrophils present in alveolar fluid of ARDS pateints which in turen reduces the pro-coagulant activity of aveolar fluid. TNF alpha inhibitors include antibodies such as adalimumab and infliximab.

Inhibition of Tissue Factor (TF)

Uttehnthal (US8,088,728B2) discloses methods of treating lung diseease such as ARDS and fibrin deposition in the airways such as the alveolar or bronchoalveolar spaces by administering human tissue factor pathway inhibitor (TFPI)

Complement Regulatory Proteins

CR1: Levin (US6,169,068B1) teaches treatment of a lung disease such as adult respiratory distress syndrome (ARDS) by administering a soluble complement receptor type 1 (sCR1). 

See also lysyl oxidase-type enzymes in the “enzyme” section

Classification: 

Pulmonary fibrotic disorders are classified into the following groups, in order of their relative occurrence: idiopathic pulmonary fibrosis (IPF), nonspecific interstitial pneumonia (NSIP), respiratory bronchiolitis-associated interstitial lung disease, desquamative interstitial pneumonia, cryptogenic organizing pneumonia, acute interstitial pneumonia, and lymphocytic interstitial pneumonia (LIP) as well as acute respiratory disress syndrome (ARDS), scleroderm-associated lung fibrosis and fibrotic damage as a sequelae of sarcoidosis.  (US application No: 12/860834).

Etiology and symptoms: 

Pulmonary fibrotic disorders are characterized by inflammation and fibrosis of the lung parenchyma. Fibrosis is the abnormal accumulation of fibrous tissue that can occur as a part of the wound healing process in damaged tissue. Such tissue damage may result from physical injury, inflammation, infection, exposure to toxins, and other causes. The etiology of these diseases has not been established, and prognosis is generally poor. Symptoms include decreased body weight, increased lung weight, presence of activated fibroblasts or fibrocytes, presence of fibrocyte precursor cells (e.g., cells that express both CD45 and collagen), abnormal lung architecture (including alveolar thickening, proliferation and expansion of pneumocytes, and honeycomb lung. Molecular symptoms include increase in one or more of the following proteins: LOXL2 (see US2009/0053224, US2009/0104201), alpha-smooth muscle actin, transforming growth factor beta-1, stromal dervied factor-1beta, stromal derirved factor-1, endothelin-1 and phosphorylated SMAD2.

Pulmonary fibrosis is a common disorder thought to be due to the destructive effects of products released from leukocytes. Pulmonayr fibrosis may depend upon the recruitment and activation of lymphotyces (Huang (US 2007/0148173).

Treatment of Pulmonary fibrotic disorders

Spangler (US12/860834) discloses inhibitors of the lysyl oxidase related protein-2 (LOXL2) such as anti-LOXL2 antibodies for the treatment of pulmonary fibrotic disorders such as IPF, interstitial pneumonia and acute respiratory distress syndrom (ARDS). 

Specific Diseases

Pulmonary fibrotic disorders are classified in the following groups, arranged in order of their frequency of occurrence: (1) IPF, nonspecific interstitial pneumonia (NSIP), respiratory bronchiolitis-associated interstitial lung disease, desquamative interstitial pneumonia, cryptogenic organizing pneumonia, acute interstitial pneumonia, and lympocytic interstitial pneumonia (LIP). ARDS has also been identified as a pulmonary fibrotic disorder. 

Acute Respiratory Distress Syndrome (ARDS):

Acute interstitial pneumonia:

Cryptogenic organizing pneumonia:

Idiopathic pulmonary fibrosis (IPF):  see outline

Lymphocytic interstitial pneumonia (LIP):

Nonspecific interstitial pneumonia (NSIP):

Airway diseases include diseases which effect the respiratory tract (e.g., lungs, mouth, nose, pulmonary, alveoli, pharynx, larynx, trachca, and bronchi). Airway diseases, such as asthma and COPD are a major health burden in the developed world.

Airway hyperresponsiveness (AHR): 

AHR is an exaggerated airway constrictive response to external triggers and is a major component of airway disease. AHR is a hallmark of asthma, but also occurs in many other airway diseases such as COPD. AHR is also known as bronchial hyperresponsiveness or airway hyperreactivity. Current treatment is non-specific and consists of bronchodilators (adrenergic or anticholigergiv) and immunosuppressants (corticosteroids).

Asthma: 

Asthma is a chronic condition involving the respiratory system in which the airways constrict, become inflamed and are lined with excessive amounts of mucus, often in response to one or more triggers. Asthma is characterized by a combination of chronic airway inflammation, airway obstruction, and airway hyperresponsiveness (AHR) to various stimuli. It is thought be be mediated priamrily by adpative immune responses mediated by allergen-specific CD4+ T cells, Th2 cytokines and allergen specific IgE, which lead to pulmonary inflammation and AHR.

Asthma is an inflammatory lung disease with airway hyperresponsiveness (AHR). The inflammatory cells release reactive oxygen species (ROS), which leak into surrounding cells.

Treatment:

Albuterol sulfate is used as a bronchodilator to treat asthma.

Steroid Receptors: are a major class of nuclear receptors represetning ligand-activated trasncription factors, known to regulate many cellular functios, including inflammatory process, energy production and apoptosis.

–Glucocorticoids (GS): are the mainstay treatment of asthma. They act by activating glucocorticoid receptors (GR). 

Gratzio (“Glucocorticoid and estrogen receptors are reduced in mitochondria of lung epithelial cells in asthma” PLoS One, June 2012, 7(6)) disclose that mitochondrial glucocorticoid (mtGR) and estrogen (mtER) receptors participate in the coordination of the cell’s energy requirement and in the mitcohondrial oxidative phosphorylation enzyme (OXPHOS) biosyntesis, affecting reative oxgyen species (ROS) generation and induction of apoptosis. They preset evidence shwoing localizatio of GR and ERbeta in lung epithelial cells.

Bronchiolitis: 

Bronchiolitis is inflammation of the bronchioles, the smallest air passages of the lungs.

Chronic obstructure pulmonary disease (COPD): 

COPD is a group of diseases characterized by limitation of airflow in the airway that is not fully reversible. COPD is the umbrella term for chronic bronchitis and/or emphysema.  In COPD the airways become narrowed, leading to a limiation of the flow of air to and from the lungs, which causes shortness of breath. In contrast to asthma, the limitaiton of airflow is poorly reversible and usually gradually gets worse over time. COPD is caused by noxious particles or gases, most commonly from smoking, which trigger an abnormal inflammatory response in the lung.

 Cystic fibrosis (CF): 

CF is a hereditary (autosomal recessive) disease affecting the exocrine (mucus) glands of the lungs, liver, pancrease, and intestines, causing progressive disability due to multisystem failure. CF is caused by a mutation in a gene called the cystic fibrosis transmembrane conductance regulator. The product of thse gene is a chloride ion channel important in creating sweat, digestive juices, and mucus. Thick mucus production in CF patients results in fequent lung infections. Lung disease results from clogging the airways due to mucosa buildup and resulting inflammation.

SLE or “lupus” is used to describe a chronic potentially debilitating or fatal autoimmune disease in which the immune system attacks the body’s cells and tissue. SLE is a prototype autoimmune and multifactorial disease characterized by the presence of autoantibodies to a diverse array of nuclear antigens including DNA, RNA and histones. These naturally occurring autoantibodies are heterogenous, exhibiting a wide heterogeneity in the recognition of nucleosides and nucleotides.

Causes: 

The specific cause of SLE is unknown. SLE is considered to be a multifactorial condition with both genetic and environmental factors involved. However, it is known that a group of genes on chromosome 6 that code for the human leukocyte antigens play a major role in a person’s susceptibility or resistance. The specific HLA antigens are DR2 and DR3. Femailes in their childbearing years (18-45) are also 8-10 times more likely to acquire SLE than men.

Deficiency in Complement Components:

Deficieincy of C1q, Clr, Cls or C4 is closely linked to defvelopment of systemic lupus erhthematosus (SLE) (as well as rheumatoid srthrisis) thought be be due in part to the inability of complement to clear immune complexes and dysing cells. Small complexes are cleaved from the circulation when they bind to complement receptors on macrophages in the speen and liver. Without complement, the complexes can grow too large to be easily cleared. The resulting aggregates can activate the alternative pathway, allowing C3 to be deposited into the matrix, with re-solubilized complexes that can be dealt with by the clearance through the liver and spleen. Failing this, these large complexes are no longer soluble and form deposits in the tissues and become a site of inflammation. Dying cells if not cleared by non-inflammatory CP activity, may serve as sources of altered self-antigens with the potential for inducing autoantibodies. (US Patent Applicaiton No: 15/895,551, published as US 2019/0247560). 

–C2 deficiency: is the most common complement deficiency in Caucasian populations with a frequency estimated between 1-10,000 for homozygous C2 deficiency patients. C2 deficiency is found in a slightly higher proportion of SLE patietns comapred to healthy controls. (US Patent Applicaiton No: 15/895,551, published as US 2019/0247560).

Diagnostic Tests: 

There is no single test that can diagnose SLE. Some tests include urinalysis to detect kidney problems, tests to measure the amount of complement proteins in the blood, complete blood cell counts to detect hematological disords and an ANA test to detect antinuclear antibodies in the blood. Studies from various laboratories have shown that after modification with ROS, DNA becomes highly immunogenic (Tasneedm, J. Autoimm. 2001, 199-205). Blount has postulated ROS-modified DNA as a more discriminating antigen for the diagnosis of SLE.

Complement Components: Measurement of serum C3 and serum C4 has traditionally been the gold standard for monitoring disease activity in patients with SLE. Howevere, tseveral major weakness of this approach are the wide range of variation of serum C3 and serum C4 levels among healthy individuals which overlaps with that observed in patients with SLE. Another problem is that C3 and C4 are precursors rather than products of complement activation. Kao (Arthritis Rheum. 2010 March; 62(3): 837-844) disclose that proteolytic fragments of complement component C4, particularly C4d, are present on the surface of normal erythrocytes and that patients with SLE have significantly higher levels of erythrocyte bound C4d and lower levels of erythrocyte expressing complement receptor 1 than patients with other diseases and healthy controls.

Symptoms: 

There are 11 criteria that help doctors tell the difference between people who have SLE and other connective tissue diseases. If a person displays 4 or more of the following 11 criteria, the person fulfills the requirement for diagnosis of SLE. 1. Malar rash (a butterfly shaped rash over the cheeks and across the bridge of the nose) 2. discoid rash (scaly disk shaped sores on the face, nect and chest 3. serositis (inflammation of the lining around the heart, lungs, abdomen, causing pain and shortness of breath 4. photsensitivity (skin rash as an unusual reaction to sunlight 5. sores and ulcers on the tongue, mouth or in the nose, 6, arthritis, 7, kideny disorder such as persistent protein or cellular cysts in the urine 8. central nervous system problems including seizures and psychosis and 9. blood problems such as low white blod cell count, low lymphoctye count, low platelet count or hemolytic anemia, 10. immune system problems such as prsence of abnormal autoantibodies to double stranded NA and 11. presence of abnormal antinuclear antibodies in the blood.

While for the most part antigenic DNA is localised to the cell nucleus and presumably becomes available as a result of cell death, evidence has been presented for the existence of DNA that is associated with the outer leaflet of the plasma membrane. This cmDNA can be a specific target for IgG autoantibodies from SLE patients. It has also been shown that autantibodies from SLE patients show a specificity, unrelated to ds- or ss-DNA which can be visible and can serve as a marker for SLE (Servais, Ann Rhuem Dis 1998, 606-618).

Treatment: 

Traditional Treatment: Traditional treatments of SLE include non-steroidal anti-inflammatory drugs (NSAIDs) including COX-2 inhibitors and salicylates (such as aspirin), anti-malarials such as hydroxychloroquine, quinacrine, corticosteroids and immunosuppressants such as methotrexate (Rheumatrex).

Antibody Treatment: Various antibodies which target relevant biomolecular markers believed to be involved in SLE are now available. ——-INF-alpha: Rontalizumab targes IFNalpha which is expressed by DCs.

–CD80/86: Abatacept targets CD80/86 on MDC which interacts with CD28 on T cells. At the B cell-T cell interaction level, Abatocept targets CD80/86 on B cells which is necessary for interaction with CD28 on T cells. Lupuzor targets T cells. 

–CD22: Epratuzumab targets CD22 and Retuximab targets CD20 on B cells (Ding, Current Opinion in Pharmacology, 2013, 13: 405-412). Originally developed for the treatment of non-Hodgkin lymphoma, epratuzumab has now been reported to be effective, with a very good safety profile, in two prototype autoimmune diseases, systemic lupus erythematosus and primary Sjogren’s syndrome (Dorner, “Targeting CD22 as a strategy for treating systemic autoimmune diseases” Therapeutics and Clinical Risk Management 2007: 3(5) 953-959).

CAR T cells:

–CD19 CART cells are being explored for treating systemic lupus erythematosus (SLE) which is caused by B cells. Depleting B cells is an unwanted side effect for cancer patients but is beneficial for lupus patients. (Ferriera “using Regulatory T cells for treatment of Type 1 diabetes, Part 2” BioProcess International 21(5) March 2023). 

See also: Drug targetting under “Pharmacology”

Lupus Nepthritis also known as “membranous glomerulonephritis” refers to an inflammation of the kidney caused by the chronic autoimmune disease SLE. Those afflicted with lupus nephritis may or may not have renal symptoms, but the disease can manifest itself through weight gain, high blood pressure, darker foamy urine or swelling around the eyes, legs, ankles or fingers. In some cases, the only renal manifestation of the disease is painless hematuria or proteinuria, but in some cases patients develop lupus nephritis, leading to acute or end stage renal failure.

Pathology

Complement is known to be involved in eitology and progression of renal inflammation and lupus nephritis. Complement cascade proteins and their proteolytically generated fragments (i.e., fragments of C3 and C4) are deposited on the glomerulocapillary, mesangial and tubulointerstitial cells during may types of renal injury. Renal biopsies are routinely stained for deposits of C3 activation fragments (C3b/iC3b/C3d) and glomerualr C3 deposits are found in most forms of glomerulonephritis (Sargsyan, Kidney International (2012) 81, 152-159

Diagnosis

–Biopsy: The most commonly used system for classifying the different histologic patters of lupus nephritis is based upon the appearance of glomeruli by light microscopy. Percutaneous renal biopsy is the gold standard for diagnosis of lupus nephritis and for monitoring the course of disease. 

–Noninvasive detection of C3 fragments in the kidneys: 

Complement activation is central to the pathogenesis of many inflammatory and autoimmune diseases. It is also a robust marker of tissue inflammation since activation of the complement system leads to the rapid covalent linkage of multiple c3b, iC3b, and C3d molecules to cell surfaces. Immunostaining for tissue C3 fragments is routinely performed on kidney biopsy samples when patients are suspected of having an autoimmune disease and when the presence of flomerular C3 deposits indicates active glomerulonephritis. (Serkova, Radiology, 255(2), 2010). 

–targeted CR2-Fc-SPIO fusion proteins: Thurman (US 13/148028; see also Sargsyan, Kidney International (2012) 81, 152-159) disclose conjugating superparagmentic iron oxide (SPIO) particles and ultrasmall SPIO particles conjugated with complement receptor type 2 (CR2)-Fc which can be used as negative contrast agents for MRA for the detection of intra-renal C3b/iC3b/C3d deposits in the kidneys of mouse models for lupus nepthritis. Interestingly, CR2-targeted SPIO reduced T2 relaxation times occured in the inner medulla of the mice kidneys, in spit of the fact that this is little C3b/iC3b/C3d at this location. The authors explain this result that during intra-renal trafficking of CR2 targeted SPIO, the CR2 interaction may trap them within the diseased kidney. 

Treatment

Patients with active proliferative nephritis are usually treated with steroids in combination with cytotoxic agents or mycophenolate mofetil. 

See also “Hemolytic anemia” under “blood diseases” and “Hemolytic uremic syndrome” under “Kidney diseases”. 

Autoimmune diseases are generally understood to be diseaes where the target of the disease is “self” or “self antigen”. Among the many types of autoimmune diseases, there are a number of diseases that are believed to involve T cell immunity directed to self antigens, including multiple sclerosis (MS), Type I diabetes, and rheumatoid arthritis (RA). Automimmune disorders are a significant clinical problem. In the US they are estimated at more than 8.5 million.

Autoimmune diseases, with the exception of rheumatoid arthritis and autoimmune thyroiditis, are individually rare, but together they affect about 5 percent of the population in Western countries. Autoimmune diseases are a poorly understood group of diseases. Mackay (New England J. Medicine, 345(5), 2001).

The autoimmune response underlying a variety of rheumatic diseases, such as with systemic lupus erythematosus (SLE), is distinguished by the production of antibodies with specificites for molecules involved in regulating the structure and assembly of nucleic acids. For example, the oncogene DEK has been shown to be an autoantigen and anti-DEK autoantibodies are associated with a distinct form of juvenile rheumatoid arthrities with iridocyclitis affecitng young girls (Wichmann, Human Immunology, 60, 1999, 57-62).

Possible Triggers for Autoimmunity and Abnormalities Associated with Automimmune Diseases

1. Molecular mimicry can trigger self-reactive B cells to produce auto-antibodies through linked recognition. For example, antibodies produced in response to streptococcus bacteria cross-react with self-antigens in kidneys, joints and heart resulting in Rheumatic fever. How this can work is the following: When a B cells takes up and presents self antigen to a T cells, T cells do not react (reactive ones were deleted) so there is no Ig production. However, sometimes after infection self antigen gets presented along with the foreign peptide which activates T cells. B cells produce antibodies here against the self-peptide.

2. Bystander Activation: is due to tissue destruction caused by a pathogen which allows self-antigens to be presented in an inflammatory milieu. A DC encounters a microbe and becomes stimulated which activates a T cells. For example, in response to theilers virus which infects neurons in the brain, T cells are recruited by inflammatory mediators. Cytotoxic T cells specific for viral antigens clear the virus. However, a breakdwon in degradation of meline as a consequence of neuronal death autoimmune disease begins mediated by myelinspecific CD4+ T cells. In the first stage, the CD4+ T cells respond to a single dominant eptiope in a myelin protein. Over time, the specificity of the CR4+ T cells response spreads form just one epitope to other epitopes in the same protein and in different proteins.

3. Dysregulation of the Innate Immune System: If infected mice with agonist for TLR 9 no disease. However, TLR 3 or 7 were sufficient. This suggested that getting Type I IFN in vivo might be enough to break the tolerant model. IFN-alpha levels are often increased in SLE pateints. TNF-alpha is increased in RA pateints.

There is growing evidence that TLRs respond to endogenous ligands (as well as TLRs) such as fibrinogen, heat shock proteins, mammalian DNA, etc. This might suggest that the primary lesion in some autoimmune diseases is due to the failure to properly discriminate self versus non-self by the innate immune system.

4. Hygiene Hypothesis: Autoimmunity is a product of both genetic and environmental factors. Interestingly, there has been a steady increase in the prevalence of autoimmune diesease, allergies and inflammatory bowel disease in developed countries. Under the “hygiene hypothesis” is is proposed that microbial exposure prevents immune mediated inflammatory disease. It is beleived that microbial antigens may compete with self-antigens for antigen processing machinery and/or binding to MHC molecules. Lymphocytes proliferating to pathogens might also out-compete self-reactive T cells for cytokines and MHC intereactions needed for survival.

5. Counter-Regulatory Theory: Tstates mircobial infections can induce regulatory T cells that make IL-10 and TGF-beta. here is literature reporting that DCs expressing indoleamine 2,3-dioxygenase (IDO), the rate limiting tryptophan-catalbolizing enzyme induce Treg responses and deplete responding T cells by eliminating tryptophan. (T cells can not make trypotphan, so if break it down, T cells die). Further, adminsitering certain TLR ligands for TLR9 and TLR4 induced IDO and can inhibit experimental asthma (see Rax et al.).

6. Susceptibility genes are shared by multiple autoimmune diseases while others are unique to a particular disease.

7. Depletion of Tregs: Depletion of different CD4+ T cell subsets results in manifestation of different autoimmune disease in mice. For example, depletion of mice of CD25-CD62L+ resulted in gastritis.

8. Aberrant expression of CD86: Several automimmune such as systemic lupus erythematosus (SLE) have aberrant CD86 expression.

9. Aberrant expression of chemokines: A hallmark of autoimmunity and other chronic diseases is the overexpression of chemokines, resulting in a detrimental local accumulation of proinflammatory immuen cells.

10. Autoantibodies: Evidence is accumulating that low levels of autantibodies occur in even healthy individuals. Thus any event that will increase their concentration may produce various degrees of pathogenicity. Among the autantibodies identified, special emphasis has ben placed on anti-DNA antibodies. Anti-DNA antibodies are known to be tightly correlated with systemic lups erythematosus (SLE). They tend to fluctuate with disease activity, and high anti-DNA serum titers are often associated with kideny damage. DNA is typically an intracellular component. However, peripheral blood cells can excrete DNA and DNA has been associated with their plasma membrane fraction. DNA receptors have also been described in human platelets and would appear to have a functional role, as their associated with DNA leads to platelet aggregation and serotonin release. Keyhani (Transplantation Proc. 27(5) 1995) isolated DNA associated with Wil2-NS (a non-immunoglobuline secreting human B lymphocyte line) and showed the role of this pmDNA. They did this by studying the presence of IgG in the sera of pateints with various autoimmune diseases directed against Wil2-NS pmDNA.

Treatment Strategies Generally

Self tolerance is though to be kept in check by four main mechanisms: central deletion fo high-avidity autoreactive T or B cell clones; peripheral delection or functional inactivaiton of autoreactive thymic T cell or bone marrow derived B escapees; exportation of mature regulatory T (Treg) cells form the thymus and de novo generation of R reg or regulatory B cells in the periphery. Sera “Antigen-specific therapeutic approaches” Nature Biotechnology, 37, 2019, 238-251)

DNA vaccines: DNA vaccination invovles the transient expression fo antigens in uninfalmed tissues using DNA vectors. For example, DNA vaccination of patients recently diagnosed with type 1 diabetes with an insulin encoding plasmid decreased the peripheral frequency of insulin reactive CD8+T cells and preserved C peptide levels. In another phase 1/2 trial, a DNA vaccine encoding myelin basic protein (MBP; BHT-3009; Bayhill Ehterapeutics) was well tolerated in pateints with MS). Sera “Antigen-specific therapeutic approaches” Nature Biotechnology, 37, 2019, 238-251)

Whole antigens: Clinal testing of whole-antigen immunotherapties autoimmunity have generally been met with failure. Sera “Antigen-specific therapeutic approaches” Nature Biotechnology, 37, 2019, 238-251). 

Cell based immunotherapy: Several gruops have used antigen coupled syngeneic lymphoic dells and erythrocytes to promote dominant tolerance. Sera “Antigen-specific therapeutic approaches” Nature Biotechnology, 37, 2019, 238-251)

Nonoparticles for antigen delivery: Nanoparticles have been used as vehicles for antigen delivery to APCs. Sera “Antigen-specific therapeutic approaches” Nature Biotechnology, 37, 2019, 238-251)

Dendritic cell transfer: Specific subsets of DCs support immune tolerance through the generation fo anergic T cells and/or antigen-speciific Treg cells. Sera “Antigen-specific therapeutic approaches” Nature Biotechnology, 37, 2019, 238-251)

Specific Types of Autoimmune Diseases

Antiphospholipid syndrome (APS): show clinical manifestations of severe predisposition to thrombosis. Ritis (J. Immunology, 2006, 177: 4794-4802) show that antiphospholipid Ab induced complement activaiton and downstream signaling via C5a receptors in neutrophils leads to the induction of Tissue Factor (TF), a key initiating component of the blood coagulation cascade. 

Primary Immune Thrombocytopenia (ITP) is an autoimmune diesease medaited by antiplatelet antibodies that cause opxonization of platelets and elimination through binding to FcyR-bearing phagocytic cells and subsequent phagocytossi. In additionk the same autoantibodies bind to megakaryocytes and impair platelet prodution. The annual incidince of ITP in the US is about 16000 cases. Although the thrombocytopenia in ITP can be severe, most patients have only minor signs of bleeding. Persistently low platelet counts (<20 x 106/L) however, are associated with an increased risk of serious bleeding, such as intracranial hemorrhage. The inital treatment for ITP is cortisoteroids, IVIg or intravenous RhD immune globulin (anti-D). These compoudns act primarily by interfering with platelet destruction and cytokine modulation. Rozrolimupad, a mixture of 25 recombinant fully human RhD specific mAbs represents a first in class of recombinant human monoclonal antibody mixtures that can be produced independently of human plasma supply. Robak, Blood, 120(18):3670-3676

Myasthenia gravis (MG): is an autoimmune and neurological disorder that affects about 200-400 people per million.

Myastehnia gravis (MG) is a neurological B cell mediated autoimmune disorder affecting the nueromuscular junction. (Vanoli “Ravulizumab for the treatment of myasthenia gravis” Expert Opinion on Biological Therapy” 2023, 23(3).)

–Symptoms

MG is characterized by muscle weakness and fatigability that worsens after their use. Pateints experience muscle weakness and symptoms including drooping eyelids, double vision and slurred speach. For the majority of patients, initial symptoms manifest in the extrinisic ocular muscles of the eye.

A quarter of patients with MG will progress to myasthenic crisis in which paralysis of the respiratory muscles occurs. In such cases, assisted ventilation is required to sustain the life of the affected patients.  (Rother, US 15/282,464).

–Causes

MG can result from immune mediated loss of acetylcholine receptors at neuromuscular junctions of skieletal muscle. A large number of patients with MG express antibodies that bind to and inhibit the activity of the nicotinic aceytlcholine recptor (AChR). The antibodies cause loss of acetylcholine receptors and diminished receptor function at the muscle end-late of the nature neuromuscular junction. (Rother, US 15/282,464) Close to 90% of MG patients have antibodies to the AChR. Binding of these antibodies to the receptor results in the failure of skeletal muscle to respond appropriately to nerve stimulation owing to antibody induced injury of the postsynaptic muscle surface. (Kusner, “effector of complement and regulation on myasthenia gravis pathogenesis” Future Drugs Ltd, 2008).

About 80% of patients with MG produce acetylcholine receptor autoantibodies. The other 20% do not, but they do experience the same MG symptoms. Many of the 20% of MG patients without acetylcholine receptor autantibodies instead generate autoantibodies to a membrane protein called MuSK, a specific muscle recptor tyrosine kinase. Athena diagnostics v. Mayo (US Ct Appeals Fed. Cir, 2019). Most patietns (about 85%) display antibodies directed against the nicotinic acetylcholine recetpor (AChR), whereas only 9% present antibodies anti-muscle-specific kinase (muSK) and 1% have antibodies anti-lipoprotein-recetpor related protein 4 (LRP4). Anti-AChr antibodies are minaly ofIgG1 and IgG3 subclass, and thus able to activate the complement cascade which is the main pathogenic mechanism of AChR+ MG. Complement activaiton ultimately leads to the disruption of the postsynaptic folds with loss of dispersion of AChRs. Another important pathogenic mechaism is antigenic modulation, where bivalent antibodies crosslink AChRs with acceleration of AChR endocytosis and degradation. Finally, anti-AChR antibodies act also by directly blocking the acetylcholine binding site on AChRs. Anti-MuSK antibodies, on the other hand, are of IgG4 subclass and thus unable to activate complement cascade and induce antigenic modulation as they are funcitonally monovalent. Their pathogenic effect is exerted by masking the binding sites in MuSK that interact with LRP4 and collagen Q, which is essential for AChR clustering. Indded, the inactivation of MUSK leads to a decrease of AChR density and an impairment of their alignemnt on the postsynaptic membrane. Anti-LRP4 are of IgG1 subclass and are thus able to activate the complement cascade. Moreover, these antiboides also inhibit AChR clustering, by blocking the agrin-LRP4 interaction. Finally, a small percentage of MG patients are defined as serongegative, as no specific pathogenic antibody has been identified. Vanoli “Ravulizumab for the treatment of myasthenia gravis” Expert Opinion on Biological Therapy” 2023, 23(3).)

The activation by antibody ultimately leads to formation of the membrane attack complex (MAC) that produces cell lysis and, in Mg, produces focal damage of the postsynaptic surface of of the muscle, which ultimately compromises neuromuscular transmission. (Soltys, “Extraocular muscle susceptibility to myasthenia gravis” Ann. Ny.Y. Acad. Sci, 1132, 220-224, 2008).

Pathophysiology of complemetn activation in MG:

Anti-acetylcholine (Ach) recetpor (AChR) antibodies activate the complemetn cascade thorugh the classical pathway by bnidng C1q on the Fc domain. The subsequence formation of C5 convertase initates the temrinal pathway which ultimately leads to the formation of the membrane attack complex (MAC), a lytic pore on the posynaptic membrane. The final effect is a focal lysis of the nuromusclar junction with disruption of the postsynaptic folds and loss of AChRs. Antibodies such as Ravulizumab (see below) binds with high affintiy to C5, inhibiting the enzymatic clevage and thereby preventing the MAC formation. Vanoli “Ravulizumab for the treatment of myasthenia gravis” Expert Opinion on Biological Therapy” 2023, 23(3).)

–Treatment:

Autoimmune attack is dependent on T cells, resulting from loss of tolerance toward self antigens at the level of the tymus. However, Abs and complement are key effectors of the loss of possynaptic AChRs and associated desstruction of the NJM. Tehrefore, the goal of MG treatment is to interrup the autoimmune prcoess by T cells and B cells using corticosteroids, thymectomy, IVIg and immunosuppressants. (Kim, J. Clin. Neurol 2011; 7: 173-183). 

MG is characterized by remarkable clinical variability, and no one treatment can be predicted to have the same beneficial (or toxic) effect on all patients. (Sanders, Autoimmunity August -September 2010, 43 (5-6), 428-435). 

—-Anti-C5 (eculizumab, Ravulizumab, etc):

Andrien (US 2017/0298123) discloses that BNJ441 (“Ravulizumab”) relative to exulizumab contains four amino acid substitutions in the H chain, Tyr-27-His, Ser-57-His, Met-429-Leu and Asn-435 Ser (note that positions 429 and 435 of BNJ441 correspond to positions 428 and 434 uner the EU numbering system). These mutations were engineered to enable an extended dosing interval verus exulizumab by increasing the circulating half-life by reducing antibody clearance and increasing the eficiency o f the FcRn-medaited antibody recylcing. Adrian teaches that the antibodies are useful for treating a variety of complement associated disorders such as aHUS, PNH and myasthenia gravis. 

Bedrosian (US Patent Application NO: 15/595,890, published as US 2017/0342139) discloses methods of treating myasthenia gravis (MG) in a patient positive for auto-antibodies binding to nicotinic acetylcholine receptor by administering eculizumab using a phase dosing schedule with an induction phase comprising 900 mg on day 1, 900 mg odses on days 7, 14, and 21 and 1200 mg as a fifth induction dose on day 28 wherein the patient is administered eculizumab for at least 26 weeks and wehrien the 28 day induction phase of eclizumab is followed by a minatenance phase of 1200 mg of eculizumab 14 days after the fift induciton dose and 200 mg eveyr 14 days therafter. 60 kg, 3300 mg to a patient weighing 60-100 kg or 3600 mg to a patient weighing greater than 100 kg. 

Fujita (US Patent Application No: 16/791,415, published as US 2020/0331993) discloses a method of treating myasthenia gravis (MG) with an anti-C5 antibody such as Ravulizumab (also known as antibody GNJ441, ALXN1210 or Ultomiris) based on weight. At day 1, 2400 mg to a patient weighing 40-60 kg, 2700 mg for a pateint weighing 60-100 kg and 3000 mg for a patient weighing greater than 100 kg. On day 15 and every 8 weeks thereafter a miantenance dose of aslo based on weight; 3000 mg to a patient weighing 40-

Rother (US Patent Application No: 15/282,464, published as US 20170015740) discloses compositions containing an inhibitor of the complement component C5 such as the antibody eculizumab sold by Alexion Pharmaceuticals for treating MG. In one embodiment, the anti-C5 antibody is adminsitered at a doese of about 600 mg every week for two or more weeks followed by 900 mg about every 14 days.

(NIHR Horizon Scanning Research & Intelligence Center “Eculizumab (Soliris) for refractory myasthenia gravis, March 2016. discloses eulizumab adminsitered IV at 1,200 mg every 2 weeks according to a schedule of randomised 900 mg IV once weekly for 4 weeks, followed by 1,200 mg IV every 2 weeks for weeks 5-26 for treatent of MG

Zhou (“anti-C5 antibody treatment ameliorates weakness in experimentally acquired myasthenia gravis” J. Immunol. (2007) discloses that in rats induced with AChR Ab, an anti-C5 mAbrestored strenght in two thirds of the rats.

—-Immunosuppressive drugs:

Most nuerologists consider some form of immunosuppression to be essential to the treatment of MG, however, there is no general concensus about which drug should be used, in which patients, and when. Corticosteroid exert profound immunosuppression by inducing T lymphocyte apoptosis, repressing transcription of inflammatory cytokines and impairing DC maturation. Corticosteroid were the first immunosuppressants used in MG therpay and are still used (i.e., prednisone) in most patients tarting with high daily doses adn then shifting to alternate day adminsitration. Remission (30%) or marked improvement (45%) occurs isn over 3/4 of patients, a further 15% have some lesser degree of improvement. (Sanders, Autoimmunity August -September 2010, 43 (5-6), 428-435)

—-Thymectomy:

Thymoma is reprotedly found in 10-30 of patients with MG. Thymectomy is associated with clinical improvement in 85% of cases and 35% of pateints appear to ahve complete remission. Thymectomy is used in non-thymomatous myasthenia to improve symptoms and in the hope of reducign subsequent drug burden. (NIHR Horizon Scanning Research & Intelligence Center “Eculizumab (Soliris) for refractory myasthenia gravis, March 2016. 

Narcolepsy: 

Narcolepsy is thought to be an autoimmune disorder where the immune system destroys certain brain cells that produce a peptide called heptocritin. Symptoms include excessive daytime sleeping and cataplexy (muscles become suddently weak or lymph). 

The FDA has approved the drug Xyrem for treatment of Narcolepsy. However, because this product contains gamma hydroxybutyrate (GHB) it is classified as a Schedule III depressants. 21 CFR 1308.13 and one must register to receive the drug. 

Hereditary angioedema (HAE): is a disease caused by deficiency of the CP control protein, C1-Inh. These individuals have recurrent swelling in the extremities, face, lips, larynx or GI tract. The patients suffer form a felling of fullness but not pain or itching in the affected area except for those with abdominal swellings who often experience acute abdominal pain. The latter two presentations are of the most concern because suffocation can occur if the airways are obstructed, and the acute swelling of the abdominal region produces intense pain often resulting in exploratory surgery. The mechanisms for production of the swelling involves not the complement enzymes, but the kinin-generating pathway. It is the product of Bradykinin through this pathway that is responsible for the tissue permeability changes that cause the swelling. Acute trematnets include C1 inhibiotr (C1-INH, Berienrt) or a replacement thrapy; ecallntide, a kallikrein inibitor;a nd icatibant, a bradykinin-2 receptor antagonist. Prophylactic treatments include attenuated adrogens and C1 inhihibor. (US Patent Applicaiton No: 15/895,551, published as US 2019/0247560).

Prions cause spongiform encephalopathies which are uniformly fatal. They have a long period from exposure to manifestation of disease (1-2 years). A variant form of the prion protein PrP-27C called PrP-27Scis required for transmission. Prions are not, however, themselves immunogenic so there is no antibody development against them. This variant is B pleated rather than an alpha helical as in the normal protein. These B-sheets polymerize and form fibers in the brain.

Among the human forms of encephalopathies caused by prions are:

Kuru which is the result of cannabalism and found in the Fore tribe of New guinea.

Creutzfeldt-Jakob disease is sporadic with an unkown source. However, there was an outbreak in Great Britain in the 1980s which was traced to the fact that people ate beef from cattle who had BSE/”mad cow disease”.

Among the encephalopathies caused by prions in animals are:

BSE or “Mad Cow Disease”

Scrapie occurs naturally in sheep and is transmissible to mice. 

Transmissible mink encephalopathy

companies:  Amplify Hope (help with rare diseases)

Drugs/Medicines:

WHO Model List of Essential Medicines      BLINK (lists medicines for a discount price). DrugBank  MERK Manual     Merk Veterinary Manual. PIMS Plus (searchable drug database, particularly potentially inappropriate drugs for older adults). FDA drug Index                    FDA labelling/product search. Medline Plus (drug/herb information)   Orange Book (Drug approvals)

CDC Drug Database (searchable database for FDA approved infectious disease drugs) FDA medication guide 

International Medical Communities:

Center for Disease Control (CDC).   International Society for Cell and Gene Therapy 

European Centre for Disease Prevention and Control (ECDC)

World Health Organization (WHO)

Rare Diseases

GARD (Genetic and Rare Diseases Center from NIH)

Save on Medical (a page where you can shop on medical procedures for the best price)

Disease Maps

Arbo Map (diseases like West nile, Dengue; CDC)

Genetic Diseases:

Hemoglobinopathies are among the most common inherited diseases around the world. They have become much more common recently in northern and central Europe, including Germany, due to immigration. The hemoglobinopathies encompass all genetic diseases of hemoglobin. They fall into two main groups: thalassemia syndromes and structural hemoglobin variants (abnormal hemoglobins). α- and β-thalassemia are the main types of thalassemia; the main structural hemoglobin variants are HbS, HbE and HbC. There are many subtypes and combined types in each group. The highly variable clinical manifestations of the hemoglobinopathies range from mild hypochromic anemia to moderate hematological disease to severe, lifelong, transfusion-dependent anemia with multiorgan involvement.

–Beta-hemoglobinopathies: affect the production of the beta-globin chain of the adult hemoglobin tetramer. This tetramer is composed of two alpha and two eta-like globin chains. When the levels of beta-globin or an altered beta-globin are reduced, as seen in beta-hemoglobinopathies, the function of red blood cells is affected, leading to anemia and multi-organ doamage. (Barker, “Advancing gene therapies for beta-hemoglobinopathies with novel gehome and epigenome editing toos” Cell & Gene Therapy Insights 2024: 10(9), 1163-1171)

—-Therapies:

——Transcriptional Gene regulation:

During fetal life, the body produces fetal hemoglobin, including the gamma-globin chain, but it is usually silenced shortly after birth. Rsearch has shown that patients who continue to express fetal hemoglobin into adulthood tend to ahve ameliorated clinical phenotypes. In some cases, people with persistent fetal hemoglobin expression, even those with mutations cuasing sickle cell diease, may not have symptoms and are hardly considered patietns. (Barker, “Advancing gene therapies for beta-hemoglobinopathies with novel gehome and epigenome editing toos” Cell & Gene Therapy Insights 2024: 10(9), 1163-1171)

Barker, (“Advancing gene therapies for beta-hemoglobinopathies with novel gehome and epigenome editing toos” Cell & Gene Therapy Insights 2024: 10(9), 1163-1171) is currentl performing research on modulating gene expression as a potential therapy for beta-hemoglobinopathies. While an ideal strategy for genetic diseases would be to directly correct the disease cuasing mutation, this is not always an easy approach. For example, beta-thalassemia is caused by over 400 different muations, meaning one would need to develop a seaprate therapy for eahc one. Fortunately, in the base of beta-hemoglobinopathies, their approach does not require a specific modificaiton of genes but rather focuses on turning them on or of to potentailly cure teh diase. Since beta-thalassemia is characterized by a dificiency in beta-globin expresion, they want to activate the gama-globin genes, which encode for teh fetal gama-globin genes that are the beta-like fetal blogin chain. This activaiton of fetal gamma-globin genes compensates for beta-globin deficiency. This approach involves inactivating a gene called BCL11A, which encodes for a potent transcriptional repression of fetal gama-globin expression. Normally in adulsts, BCL11A factor binds to the fetal gama-globin promoters and represses fetal hemoglobin production. By knocking out BC11Am tge gama globin gene can be reactivated, stopping the repression of fetal hemoglobin. This approach relies on the CRISPR-Cas9 system, a nuclease based system that genrates double stran breaks in the DNA, acting as a molecular siccsors. In the alternative, just one base can be changed using a base editor to create a new binding site for a transcriptional activtor. For example, by chaing adenine into guanine, a binding site for a potent transcriptional activator called KLF1 that binds to the gama-globin promoter and activates gene expression can be accomplished. Other approaches include epigenome editors based on CRISPR-Cas9. Histone modifications on teh gama-globin promoter are introduced that are typically associated with activate transcription of fetal gama-globin genes. To activate gama-globin genes, one would also need to remove DNA methylation, as this typically switches off genes. 

Rare Genetic Diseases:

80% of rare diseases are enetic. As a result, cell and gene therapy hold great promise for their treatment, especially those resulting from single gene defects (monogenic). Advances in gene-editing technologies, such as those based on clustered reularly interspaced palindromic repeats (CRISPR) and assocaited rptoein 9 (Cas9), enable precise correction of disease causing mutations in patient ceels, offering potential cures for previously untreatable conditions. 

One of the major hurdles in Orphan-drug development is the small size of patient populations affected by rare diseases. Limited patient numbers make it hard to recruit participants for clinical trials, leading to slower trial enrollment. 

Aromatic L-amino acid decarboxylase (AADC) (PTC Therapeutics) is a rare disesase in pediatric patients aged 18 months and up. AADC deviciency is a genetic disordr casued by a mutaiton in teh DDC gene, which leads to insufficient levels of the AADC prtoein. In turn, AADC deviciency is characterized by compromised production of dopamine, serotonin and other neurotransmitters, resulting in its key symptoms of developmental delays, muscle stiffness, movement problems and lethargy. Most patients with AADC deficiency need lifelong case, adn the disease can be fatal. Upstaza targets the underslying casue of AADC deficiency by delivering a functional copy of the DDC gene. The gene therapy is delivered right into the brain through a minimally invasive procedure and is meant to be a one-time treatment. In July 2022, the European Commisison granted the gene therapy, allowing its use in all 27 European Union member states. In March 2023, England’s National Instittue for Health and Care Excellence recommended the use of Upstaza for the treatment of AADC deficiency. (BioSpace, “FDA Action alert: Journey, Merus, PTC and Autolus” November 4, 2024). 

Arrhythmogenic cariomyopath (ACM): is caused by a genetic defect on the surface of heart muscle cells where the interlinking chains between cardiac cells are comprosimed. Over time, such problems lead to structural deffects in the heart. People often discover that they have the disease during strenuous exercise in their 20-30s. A person can wake up in the hosptial with an implanted defibrillator after haivng gone through an arrhymia sotrm that has cuased cardiac arrest. The defibrillator can save the person from acute trauma of cardiac arrest but does not protect them from arrhythmia burden. 

Regenerative Medicine is investigating a investigational new drug (IND), PjB-0402, as a candidate gene therapy designed to treat desmoplakin gene variant arrhythmogenic cardiomyopathy (DSP-ACM). The drug uses a known cariometabolic associated protein called FGF21 to treat patients. The drug is delivered to the liver, which then creates FGF21 and secretes it into the bloodstream. The investigation was supported by a grant of 4 million by the California Institute for Regnerative Medicine. 

DFNB9: is a form of autosomal recessive deafness cuased by mutations in OTOF, the otoferlin gene. There are more than 150 genes that are known to cuase deafness when mutated. However many of these are rare; there are about 6 or 7 genes that are the most common. Many groups are targeting one gene OTOF. But OTOF mutations are not the most common in hereditary deafness, accounting for 1-8% of genetic hearing loss. The most common type is DFNB1, casued by mutations int he GJB2 gene, which encodes connexin 26. But targeting OTOF has some advantages; first, many AAV vectors can target the inner hair cells but not the otuer hair cells. If a disease affects both types of hair cells, the delivery vector only targets one type and does not work. However, OTOF is expressed only in the inner hair cells, making the gene an attractive target. Second, hair cells (and other tissues) degeenrate if they are not functioning properly. Becasue the ear develops in utero, it is fully mature by the time the baby is born, so that cells may have already started to degeenrate and the window for intervention may have been missed. But with OTOF mutations, the hair cells do not degnerate. So, treating eyars latter can resore function. Akouos (a wholly owned subsidiary of Eli Lilly) accouned positive intial clinical resutls in AK-OTOF-101 gene therapy study. 

Monogenetic Disease epidermolysis Bullosa (EB): is a rare, monogentic skin dsiease characterised by the formation of extensive blisters and wounds on the skin and mucous membranes upon minimal mechnical trama. EB is characterised by the formation of extended blisters and lesions on teh patient’s skin upon minimal mechanical stresses. Causal for this severe condition are genetic mutations in genes, leading to teh functional impairment, reduction, or absence of teh encoded protein within the skin’s basement membrane zone connecting the epidermis to the underlying dermis. EB causing mutations can be present in at least 16 different genes encoding structural proteins within the skin essential for dermal-epidermal connectivity.  

Disease Treatment Strategies:

Cell-Based therapeutics: which involves the adminsitraiton of cells as living agents to fight diase has recently epxerienced explosive growth. Although cell based therapeis have many of the same translational barreirs as gene therapies, ncluding safety concerns over the potential tumorigenicity and high manufacturing costs that challenge product reimbusement, they have unique intrinsic features that offer the potentail for enhanced efficacy against disease. For example, cells can naturally migrate, localize and even undergo proliferation in specific tissues or compartments. Cell based modalities that harness these properties thus hold potential for biodistribution and targeted delivery advantages not only over biologics, which are subject to limitations imposed by they PK/PD profies, but also voer gene therapies, for which tropism specificity remian challenging to engineer. Furthemore, cells can actively sense a wide variety of extrnsic imputs form small molecuels, cell surface marker proteins and even physical forces. (Bashor, “Engineering the next generation of cell-based therpaeutics” Nature Reviews Drug Discovery)

–CART-T therapy: Progress in the commercializaiton of cell based therpaties has dramatically accelared within the past decade following FDA approval of CAR-T therapy. CAR-T products for refractory multiple myeloma as well as ALL and LBCI have reached the market, and there is potential for approval of therapies using donor derived natural kilelr (NK) cells.. Currently, numerous clinical trails have been completed for solid and liquid tumour indications, suing various effector cells types. However, despite this ongoing diversificaiton, most adoptive cancer cell based therapy trails continue to use patient deived T cells that, alhtough successful with haematological malignancies, present a persistent set of challenges for treating other cancer. These challenges include afety issues posed by cytokine release syndrome which reults from excessive activaiton of uncontrolled expansion of adminstiered cells. Addkitonally, a need exits for refined tumour antigen targeting to prevent antigen escape or off target cytotoxicity, both key hindrances to the applicaiton of CAR-T therpaies to solid tumors. (Bashor, “Engineering the next generation of cell-based therpaeutics” Nature Reviews Drug Discovery)

Recent advances in cell based therpaeutics have been driven by the development of CRISPR and CRISPR accocaited (Cas) prtoeins as programmable tools to engineer the human genome and epigenome in living cells. CRISPR-Cas systems can be targeted to specific genomic loci simply by altering the protospacer sequences of an associated guid RNA (gRNA), which provides an advantage over other genome editing tools, such as zinc finger nuclease (ZFN) and transcription activator-like effector nuclears (TALEN) prtoeins, that require protein engineering to target new sequences. Multiplexed CRISP-Cas9 based genome editing using Cas9 mRNA dn gRNAs that target T cell receptor (TCR), beta2-microglobulin and PD! genes simulanetously has been used in combination with a lentivirally delivered CAR, to generate allogeneic CAR-T cells deficient in TCR, HLA class I molecule and PD1 and has opened the door to universal CAR-T cells. These types of cominatorial starties could solve some o the grand challenges tht face cell therpaies, particulalry by decreasing the immunogenic profiels of autologus cell sources and enhancing the vibility of engineered cells. Bashor, “Engineering the next generation of cell-based therpaeutics” Nature Reviews Drug Discovery)

Patient Variability; Personalized Medicine:

Introduction: Existing tools often fail to understand differences between patients with the same disease. For physicians, diagnostic limitations present great challenges in delivering the best possible treatment to their patients. For ptients, the lack of effective tools means a potential waste of time exactly when time is of the essence. Payors also find themselves covering costs for expensive treatments that may or may not offer benefits to the treated pateints. 

Biomarkers for Patient Variability: designing a biomarker(s) that enable identificaiton of patient differentiators, one can optimize how clinicians choose therapies and select patients for clinical trials. Both of these factors can improve success rates for late stage clinical trials. 

Noncoding RNAs; RNA modificaitons: In one study, a novel noncoding gene was overexpressed in patients who eventually relapsed, but not in other patients. With respect to influenza, two long intergenic noncoding RNAs were assocaited with immune response. The noncoding RNAs became highly methylated after exposure to influenza. Shorter noncoding RNAs were also altered after infection. (see Snell, “direct RNA sequencing supports novel discoveries in RNA biology” in Genetic Engineering & Biotechnology News, November 2024)