Production Of Immune Complexes Research Articles

Immune Complex Glomerulonephritis in a Patient with Myelodysplastic Syndrome with Ring Sideroblasts Treated with Luspatercept

Myelodysplastic syndromes (MDS) are a group of clonal myeloid disorders distinguished by dysplastic bone marrow and peripheral blood cells, ineffective hematopoiesis, and an increased risk of developing acute myeloid leukemia (AML). MDS with ring sideroblasts (MDS-RS) is a favorable outcome subtype with a lower frequency of AML transformation. The FDA recently approved luspatercept for the treatment of patients with very-low-, low-, and intermediate-risk MDS-RS who have failed to correct anemia with an erythropoiesis-stimulating agent (ESA) and require two units of red blood cells over an eight-week period. This drug's pharmacology is based on the critical role of the transforming growth factor-beta (TGF-β) pathway in regulating erythropoiesis. In this case report, we describe for the first time an acute kidney injury caused by membranoproliferative glomerulonephritis (MPGN) in a patient with MDS-RS who was treated with luspatercept. We propose that a multi-hit hypothesis could explain the immunopathogenesis. A first unknown hit may stimulate IgA immune complex production, whereas luspatercept administration acts as a second hit, causing Smad1-5-8 phosphorylation. This intriguing case report on immune-complex-mediated proliferative glomerulonephritis following luspatercept treatment generates hypotheses and stimulates further research in this area.

Primary membranous nephropathy: an endless story.

Primary membranous nephropathy (PMN) is an autoimmune disease caused by the attack of autoantibodies against podocyte antigens leading to the in situ production of immune complexes. However, the etiology is unknown and the pathogenesis is still far from being completely elucidated. MN is prevalently idiopathic or primary, but in about 20-30% of cases it is secondary to chronic infections, systemic diseases, exposure to drugs, or malignancy. The differentiation between primary and secondary MN may be difficult, particularly when MN precedes signs and symptoms of the original disease, as in some cases of cancer or systemic lupus erythematosus. The natural course of PMN is variable, but in the long term 40-60% of patients with nephrotic syndrome progress to end-stage renal disease (ESRD) or die from thrombotic or cardiovascular events. PMN is a treatable disease. Patients with asymptomatic proteinuria should receive supportive care. Immunosuppressive treatments should be given to patients with nephrotic syndrome or risk of progression. The most frequently adopted treatments rely on cyclical therapy alternating steroids with a cytotoxic agent every other month, i.e., rituximab at different doses, or calcineurin inhibitors plus low-dose steroids. A good rate of response may be obtained but relapses can occur. Randomized controlled trials, with adequate size, long-term follow-up, and fair definition of endpoints are needed to identify treatment with the best therapeutic index.

POS1443 RELATIONSHIP BETWEEN FIBRINOGEN TO ALBUMIN RATIO AND DISEASE ACTIVITY IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background:Systemic lupus erythematosus (SLE) is a systemic inflammatory autoimmune disease characterized by excessive production of immune complexes and proinflammatory cytokine. Low complement, neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) have been used as inflammatory biomarkers to assess the disease activity of SLE. Recently, the fibrinogen to albumin ratio (FAR) has emerged as an effective indicator to reflect the systemic inflammation in many diseases. However, the role of FAR in SLE has been scarcely studied.Objectives:This study was to investigate the association between FAR and SLE Disease Activity Index 2000 (SLEDAI-2K) in SLE.Methods:This retrospective study included 74 SLE patients and 79 age- and sex-matched healthy subjects. According to the SLEDAI-2K score, SLE patients were divided into Group 1 with a score ≤ 9 (patients with mild disease activity, N = 41) and Group 2 with a score > 9 (patients with moderate to severe disease activity, N = 33). Neutrophil, lymphocyte, monocyte, platelet, albumin, fibrinogen, NLR, PLR, monocyte to lymphocyte ratio (MLR), FAR, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), complement 3 (C3), complement 4 (C4) and SLEDAI-2K were collected. Receiver operation characteristic (ROC) curves were conducted to discriminate SLE patients from healthy controls and SLE patients with different disease activity. Correlations between the inflammatory markers and SLEDAI-2K were analyzed.Results:FAR, NLR, PLR, MLR and fibrinogen in SLE patients were higher compared to those of the healthy controls (P < 0.05), while albumin was lower (P < 0.05). Patients in Group 2 had higher levels of FAR, NLR, PLR, fibrinogen and CRP than those in Group 1 (P < 0.05) except MLR (P = 0.579) and ESR (P = 0.130), albumin and C3 were lower (P < 0.05). Furthermore, FAR were higher in SLE patients with nephritis than those without nephritis (P = 0.009). The ROC curve for differentiating SLE patients from healthy individuals showed that the area under curve (AUC) of FAR (0.801, 95%CI: 0.728 - 0.874) and albumin (0.833, 95%CI: 0.764-0.903) were higher than NLR (0.798, 95%CI: 0.725 - 0.871), PLR (0.680, 95%CI: 0.588 - 0.771), MLR (0.785, 95%CI: 0.712 - 0.859) and fibrinogen (0.645, 95%CI: 0.556 - 0.733). Besides, the ROC curve for predicting the disease activity of SLE patients indicated that the AUC of FAR (0.911, 95%CI: 0. 842 - 0.980) was higher than NLR (0.697, 95%CI: 0.574 - 0.821), PLR (0.695, 95%CI: 0.571 - 0.820), MLR (0.553, 95%CI: 0.415 - 0.691), fibrinogen (0.718, 95%CI: 0.590 - 0.847), CRP (0.672, 95%CI: 0.540 - 0.803), ESR (0.640, 95%CI: 0.510 - 0.770), C3 (0.644, 95%CI: 0.515 - 0.773), C4 (0.544, 95%CI: 0.407 - 0.681) and albumin (0.894, 95%CI: 0.819 - 0.969). FAR was positively correlated with SLEDAI-2K (r = 0.682, P < 0.001), yielding a highest relevance than other inflammatory parameters.Conclusion:FAR was significantly elevated in SLE patients compared with healthy subjects and related with the disease activity of SLE. FAR might be a useful inflammatory index to evaluate disease activity in patients with SLE.

Metabolic pathways mediate pathogenesis and offer targets for treatment in rheumatic diseases.

The cause of autoimmune diseases remains incompletely understood. Here, we highlight recent advances in the role of proinflammatory metabolic pathways in autoimmune disease, including treatment with antioxidants and mechanistic target of rapamycin (mTOR) inhibitors. Recent studies show that mTOR pathway activation, glucose utilization, mitochondrial oxidative phosphorylation, and antioxidant defenses play critical roles in the pathogenesis of autoimmune diseases, including rheumatoid arthritis, immune thrombocytopenia, Sjögren's syndrome, large vessel vasculitis, and systemic lupus erythematosus. mTOR activity leads to Th1 and Th17 cell proliferation, Treg depletion, plasma cell differentiation, macrophage dysfunction, and increased antibody and immune complex production, ultimately resulting in tissue inflammation. mTOR also affects the function of connective tissue cells, including fibroblast-like synoviocytes, endothelial cells, and podocytes. mTOR inhibition via rapamycin and N-acetylcysteine, and blockade of glucose utilization show clinical efficacy in both mouse models and clinical trials, such as systemic lupus erythematosus. The mTOR pathway is a central regulator of growth and survival signals, integrating environmental cues to control cell proliferation and differentiation. Activation of mTOR underlies inflammatory lineage specification, and mTOR blockade-based therapies show promising efficacy in several autoimmune diseases.

An outbreak of acute viral myositis with different outcomes: A case series

Viral myositis is induced by direct muscle invasion, molecular mimicry, production of immune complexes, immune dysregulation, and various other mechanisms. The pathogenesis of this entity is still unclear. Here, we report a case series of viral myositis with varied clinical presentations who had different outcomes ranging from complete recovery to death. To report a variety of clinical and laboratory presentation of an outbreak of viral myositis. This was a case series of seven patients, describing clinical, electrophysiological, and laboratory tests and histopathology and treatment results. The study showed a benign course in 2, recurrence in 1, fulminant necrotizing myositis in 4, and coexisting Guillain–Barre syndrome in 2 with 1 patient culminating to death in the latter group. The variability in outcome of viral myositis suggests that there are some genetic factors which lead to fulminant necrotizing myositis in contrast to the patients experiencing a benign course of myositis.

Abnormal B Cell Development in Systemic Lupus Erythematosus: What the Genetics Tell Us.

Although the immunologic abnormalities in SLE are complex, numerous, and not fully understood, B cells have a central role in the development of the disease, from driving immune complex production to secretion of proinflammatory cytokines. Since SLE is an archetypal complex disease, the genetic association data reflect that complexity, with many variants, affecting several areas of the immune system 13, 14. The advent of GWAS has identified many potential abnormal pathways relevant to the breaking of self tolerance in SLE (summarized in Table 1). The data emphasize the central role of B cells, with a significant proportion of identified genes affecting B cell function and epigenetic annotation reinforcing this 13, 14, 65, 66. GWAS have also helped to explain clinical variability between individuals—it is easy to see how each patient is likely to have a different combination of risk variants resulting in a pattern of immune dysfunction unique to that individual. We can already see how variants in TLR genes can help predict disease and serologic markers, or how variants in the gene for Lyn can protect against hematologic involvement 36, 49. Traditionally, B cell–targeted therapy has mostly been focused on depletion of numbers (e.g., through targeting CD20‐mediated depletion through rituximab), but with our growing understanding, less crude approaches are being investigated. For example, Aiolos depletion therapy with the CC‐220 molecule results in down‐regulation of genes mediating B cell differentiation, reduces proliferation, and inhibits antibody secretion in B cells from SLE patients 69. Emerging therapy such as epratuzumab (a monoclonal antibody to CD22) has been shown to block B cell differentiation and activation directly through selective inhibition of BLIMP‐1 (encoded by PRDM1), demonstrating how data from GWAS can inform future drug therapy 70. Although the results from GWAS confirm the complexity of SLE pathogenesis and show that different intrinsic B cell abnormalities are likely to drive disease in each individual case, the principles underlying the loss of central tolerance (deficient BCR signaling) and peripheral tolerance (dysregulated T cell–B cell interaction) are universal. Genetic information helps us to personalize therapy, whereby relevant molecules can be targeted through understanding the exact pathways involved in an individual's disease.

The ID genotype of MDM2 40 bp insertion/deletion polymorphism was associated with lower risk of SLE

BackgroundIn patients with systemic lupus erythematosus (SLE), loss of immunological tolerance to self-nuclear antigens and abnormal activation of self-reactive T and B cells lead to self-antibodies and immune complex production....

Hepatitis C virus and neurological damage.

Chronic hepatitis C virus (HCV) infection exhibits a wide range of extrahepatic complications, affecting various organs in the human body. Numerous HCV patients suffer neurological manifestations, ranging from cognitive impairment to peripheral neuropathy. Overexpression of the host immune response leads to the production of immune complexes, cryoglobulins, as well as autoantibodies, which is a major pathogenic mechanism responsible for nervous system dysfunction. Alternatively circulating inflammatory cytokines and chemokines and HCV replication in neurons is another factor that severely affects the nervous system. Furthermore, HCV infection causes both sensory and motor peripheral neuropathy in the mixed cryoglobulinemia as well as known as an important risk aspect for stroke. These extrahepatic manifestations are the reason behind underlying hepatic encephalopathy and chronic liver disease. The brain is an apt location for HCV replication, where the HCV virus may directly wield neurotoxicity. Other mechanisms that takes place by chronic HCV infection due the pathogenesis of neuropsychiatric disorders includes derangement of metabolic pathways of infected cells, autoimmune disorders, systemic or cerebral inflammation and alterations in neurotransmitter circuits. HCV and its pathogenic role is suggested by enhancement of psychiatric and neurological symptoms in patients attaining a sustained virologic response followed by treatment with interferon; however, further studies are required to fully assess the impact of HCV infection and its specific antiviral targets associated with neuropsychiatric disorders.

Viral myositis as a close mimicker of polymyositis

Viruses can induce myositis through persistent infections, molecular mimicry, production of immune complexes, immune dysregulation, or other mechanisms. Self limited viral myositis is more common among children and has been seen to be mostly associated with influenza A and B. We report a case of 15-year-old boy who presented with proximal muscle weakness following 3 weeks after an episode of fever. Muscle necrosis was evident from the raised creatine kinase levels and myoglobinuria. The patient improved slowly over a period of weeks without any treatment except for adequate hydration.

Kinetics and pathogenicity of autoantibodies induced by mercuric chloride in the brown Norway rat

Repeated low-dose injections of mercuric chloride (HgCl2) in the brown Norway (BN) rat result in polyclonal activation which includes the induction of anti-glomerular basement membrane (GBM) autoantibodies. We examined the kinetics of various autoantibodies produced in vivo, general features of polyclonal activation such as total IgG levels and immune complex formation, and the relationship between organ specific autoimmunity and tissue injury in the kidney and thyroid. The production of immune complexes and autoantibodies to GBM and thyroglobulin was short lived, and the increase in levels of total IgG and antibodies to ssDNA and dsDNA was prolonged; the antibody response to collagen types I and II was intermediate in duration. Autoantibodies induced by HgCl2 caused only mild and variable tissue injury in the kidneys and did not induce abnormalities in the thyroid. These studies demonstrate that immunostimulation by mercury may result in the formation of a range of autoantibodies, with variable kinetics and pathogenicity.

Towards understanding the pathology of erythema nodosum leprosum

Erythema nodosum leprosum (ENL) is an immune-mediated complication of leprosy presenting with inflammatory skin nodules and involvement of multiple organ systems, often running a protracted course. Immune complex production and deposition as well as complement activation have long been regarded as the principal aetiology of ENL. However, new data show that cell-mediated immunity is also important. We have performed a critical analysis of studies on the pathology of ENL. Our main findings are as follows. ENL is characterised by an inflammatory infiltrate of neutrophils with vasculitis and/or panniculitis. There is deposition of immune complexes and complement together with Mycobacterium leprae antigens in the skin. Changes in serum levels of Igs indicate a transient, localised immune response. The major T-cell subtype in ENL is the CD4 cell, in contrast to lepromatous leprosy where CD8 cells predominate. The cytokines TNFalpha and IL-6 are consistently found whilst IL-4 is low or absent in ENL lesions, indicating a T(H)1 type response. Keratinocyte 1a and intercellular adhesion molecule-1 (ICAM-1) have been shown to be present in the epidermis in ENL, which is evidence of a cell-mediated immune response. Co-stimulatory molecules such as B7-1 have also been studied but further work is needed to draw strong conclusions. We also highlight potential areas for future research.

Plasmodium malariae: parasite and disease.

A review of the life history of Plasmodium malariae, the quartan malaria parasite of humans, is presented. Much of the information is based on data obtained from induced infections in humans who were given malaria therapy for the treatment of neurosyphilis between 1940 and 1963. Prepatent periods (i.e., the time until the first day of parasite detection) fever episodes, and maximum parasitemias as a result of infection with P. malariae were obtained and are presented. Experimental and known vectors of the parasite are also discussed. Splenectomized chimpanzees and New World monkeys are readily infected and serve as sources of parasites and antigens for diagnostic and molecular studies. South American monkeys are naturally infected with a parasite known as Plasmodium brasilianum. This parasite appears to be P. malariae that has adapted from humans to grow in monkeys, probably within the last 500 years. Infection with P. malariae is associated with the production of immune complexes in the kidneys and the associated nephrotic syndrome. The essential lesions are a thickening of the glomerular basement membrane and endocapillary cell proliferation. Studies of monkeys infected with P. malariae indicate the same pathology as that demonstrated in humans.

9 Steroid resistance: how can we solve this problem in COPD?

Neuropsychiatric (NP) involvement in Systemic Lupus Erythematosus (SLE), can be a severe and troubling manifestation of the disease that heavily impacts patient’s health, quality of life and disease outcome. It is one of the most complex expressions of SLE which can affect central, peripheral and autonomous nervous system. Complex interrelated pathogenetic mechanisms, including genetic factors, vasculopathy, vascular occlusion, neuroendocrine-immune imbalance, tissue and neuronal damage mediated by autoantibodies, inflammatory mediators, blood brain barrier dysfunction and direct neuronal cell death can be all involved. About NPSLE a number of issues are still matter of debate: from classification and burden of NPSLE to attribution and diagnosis. The role of neuroimaging and new methods of investigation still remain pivotal and rapidly evolving as well as is the increasing knowledge in the pathogenesis. Overall, two main pathogenetic pathways have been recognized yielding different clinical phenotypes: a predominant ischemic-vascular one involving large and small blood vessels, mediated by aPL, immune complexes and leuko-agglutination which it is manifested with more frequent focal NP clinical pictures and a predominantly inflammatory-neurotoxic one mediated by complement activation, increased permeability of the BBB, intrathecal migration of autoantibodies, local production of immune complexes and pro-inflammatory cytokines and other inflammatory mediators usually appearing as diffuse NP manifestations. In the attempt to depict a journey throughout NPSLE from diagnosis to a reasoned therapeutic approach, classification, epidemiology, attribution, risk factors, diagnostic challenges, neuroimaging techniques and pathogenesis will be considered in this narrative review based on the most relevant and recent published data.

Treating Irritable Bowel Syndrome with a Food Elimination Diet Followed by Food Challenge and Probiotics

Objective: In Irritable Bowel Syndrome, the gut-associated immune system may be up-regulated resulting in immune complex production, low-grade inflammation, loss of Class I bacteria, and translocation of inflammatory mediators and macromolecules outside of the GI lumen. Since food intolerance may be one of the reasons for this upregulation, our goal was to investigate the role of food intolerance in IBS patients.Methods: In this open label pilot study, we enrolled 20 patients with IBS by Rome II criteria (15 women, ages 24–81) who had failed standard medical therapies in a tertiary care GI clinic. Baseline serum IgE and IgG food and mold panels, and comprehensive stool analysis (CSA) were performed. Breath-hydrogen testing and IBS Quality-of-Life (QOL) questionnaires were obtained. Patients underwent food elimination diets based on the results of food and mold panels followed by controlled food challenge. Probiotics were also introduced. Repeat testing was performed at 6-months. We followed up with this cohort at 1 year after trial completion to assess the reported intervention and for placebo effect.Results: Baseline abnormalities were identified on serum IgG food and mold panels in 100% of the study subjects with significant improvement after food elimination and rotation diet (p < 0.05). Significant improvements were seen in stool frequency (p < 0.05), pain (p < 0.05), and IBS-QOL scores (p < 0.0001). Imbalances of beneficial flora and dysbiotic flora were identified in 100% of subjects by CSA. There was a trend to improvement of beneficial flora after treatment but no change in dysbiotic flora. The 1-year follow up demonstrated significant continued adherence to the food rotation diet (4.00 ± 1.45), minimal symptomatic problems with IBS (4.00 ± 1.17), and perception of control over IBS (4.15 ± 1.23). The continued use of probiotics was considered less helpful (3.40 ± 1.60).Conclusion: These data demonstrate that identifying and appropriately addressing food sensitivity in IBS patients not previously responding to standard therapy results in a sustained clinical response and impacts on overall well being and quality of life in this challenging entity.

Pathogenesis of neutropenia in large granular lymphocyte leukemia and Felty syndrome

T-cell large granular lymphocyte leukemia (TLGL) is an atypical chronic lymphoproliferative disorder derived from cytotoxic T-cells (CTL). Unlike most forms of leukemia, the pattern of bone marrow infiltration in TLGL may be subtle and the cytopenias are often lineage specific, with neutropenia dominating. Both granulocytic survival and proliferation defects are observed and are mediated by humoral and cell-mediated mechanisms respectively. Splenic production of immune complexes induces a neutrophil survival defect, where as Fas expression by leukemic CTL results in a marrow based proliferation defect. These humoral and cell-mediated pathways induce granulocytic apoptosis through independent intracellular mechanisms which are not mutually exclusive and may be observed concurrently in individual patients with either TLGL or FS. A variety of therapeutic interventions have been utilized in the management of TLGL and Felty syndrome, including methotrexate, cyclosporine A, cyclophosphamide, glucocorticoids, myeloid colony stimulating factors and splenectomy. Their efficacy and mechanisms of action are reviewed.

Preeclampsia: the Death of Goliath

In this review, a novel and unifying pathophysiologic mechanism of preeclampsia is presented whereby a minimal excess of placental immune complex production versus removal causes a proinflammatory autoamplification cascade of trophoblast apoptosis/necrosis and oxidative stress, culminating in clinical preeclampsia. This concept immediately leads to a plethora of new and robust therapeutic strategies.

Cryoglobulinemic vasculitis

Cryoglobulinemic vasculitis is an immune-complex-mediated systemic vasculitis involving small-medium-sized vessels. A causative role of hepatitis C virus in over 80% patients has been definitively established, with heterogeneous geographical distribution. This review focuses on recent etiopathogenetic, clinico-diagnostic, and therapeutical studies. Hepatitis C virus cannot be integrated into the host genome; it may exert a chronic stimulus to the immune system. The interaction between hepatitis C virus envelope protein E2 with B-cell CD 81 receptor may increase the frequency of VDJ rearrangement in antigen-reactive B lymphocytes. One consequence is the activation of various protooncogenes, including anti-apoptotic Bcl-2. The extended B-cell survival is responsible for autoantibody and immune-complex production, including mixed cryoglobulins; some malignancies, mainly B-cell lymphomas, may complicate cryoglobulinemic vasculitis. Environmental or viral/host genetic cofactors should be relevant in the pathogenesis of hepatitis C virus-related diseases. Cryoglobulinemic vasculitis may overlap with other diseases (systemic vasculitides, Sjögren's syndrome, autoimmune hepatitis, lymphoma), which should be carefully considered for a correct diagnosis and treatment. Cumulative survival of cryoglobulinemic vasculitis is significantly lower compared with the general population. Therapeutic strategies for cryoglobulinemic vasculitis include etiologic (antiviral), pathogenetic (cyclophosfamide, rituximab), or symptomatic (steroids, plasmapheresis) treatments, which should be tailored to the individual patient according to the severity/activity of clinical symptoms. Cryoglobulinemic vasculitis represents a crossroads among autoimmune and lymphoproliferative disorders; as hepatitis C virus infection is the major causative factor, cryoglobulinemic vasculitis is an important model for etiopathogenetic studies of virus-related diseases.

Mixed cryoglobulinaemia: a cross-road between autoimmune and lymphoproliferative disorders.

Mixed cryoglobulinaemia (MC) is a systemic vasculitis, secondary to the deposition in small and medium-sized blood vessels of circulating immune complexes, mainly the cryoglobulins, and complement. MC is characterised by a typical clinical triad (purpura, weakness, arthralgias) and by one or more organ involvement: chronic hepatitis, glomerulonephritis, peripheral neuropathy, skin ulcers and diffuse vasculitis. In a limited number of MC patients, a malignancy, that is B-cell non-Hodgkin's lymphoma or hepatocellular carcinoma, may also develop. Hepatitis C virus (HCV) infection has been found in the majority of patients with MC; the frequency of HCV markers (91%) was significantly higher than other rheumatic diseases (6.4%), namely systemic lupus, Sjögren's syndrome, rheumatoid arthritis and systemic sclerosis, or healthy controls (1.2%). The HCV infection of lymphoid tissues may represent the remote event leading to B-lymphocyte proliferation responsible for autoantibodies and immune-complex production. In a similar way, HCV infection may also be involved in the pathogenesis of other autoimmune (glomerulonephritis, thyroiditis, lung fibrosis, autoimmune hepatitis, porphyria cutanea tarda) and lymphoproliferative disorders (monoclonal gammopathies, B-cell lymphomas). MC shares numerous clinico-serological and pathological features with the above disorders. HCV seems to be their common etiological agent; however, a variable combination of unknown co-factors (infectious, genetic, environmental) should be determinant for the appearance of different clinical patterns.

Immune Functional Impairment in Patients with Clinical Abnormalities and Silicone Breast Implants

Silicone, previously thought to be a biologically inert and harmless material, has now been reported to elicit antibody response and to be responsible for adjuvant disease in humans. The present study was designed to evaluate the immune function of forty individuals who had undergone silicone breast augmentation for a period of longer than ten years and who were compared with 40 sex and age-matched controls. The following immunological functions were studied: lymphocyte subset analysis, lymphocyte mitogenic response, NK cytotoxic activity and markers for autoimmunity such as ANA, rheumatoid factor immune complexes such as smooth muscle, myelin, and thyroid, and tissue antibodies. Results of lymphocyte subpopulation analysis showed significantly elevated T helper/suppressor ratio in 60% and significantly decreased T helper/suppressor ratio in 7.5% of the silicone implant group, while the control group showed increased helper/suppressor ratio only in 10% of tested individuals and no significant decrease in the T helper/suppressor ratio. There was 20% inhibition in T cell mitogenic responses in the silicone implant group, which is significant when compared to the controls. When NK cytotoxic activity was compared between the two groups, significant inhibition in the ability of lymphocytes to kill tumor target cells was observed in the silicone implant group. This inability of target cell lysis was attributed to the demonstrated lack of granularity of NK cells from the silicone implant group. There was significant increase in: immune complexes, anti-nuclear antibodies, anti-thyroid antibodies, anti-striated muscle cell antibody, and anti-myelin basic protein antibodies. These immunological abnormalities in individuals who underwent silicone breast augmentation indicate a mechanism of tissue injury to these patients, causing autoimmune diseases or syndromes. Since autoimmunity in some other conditions is associated with abnormalities in the HLA serotyping system, and since some collagen vascular diseases have been associated with a higher incidence of the HLA serotyping system, it is recommended that HLA studies be included in future investigations of immune-mediated abnormalities associated with silicone breast augmentation. Our findings here show definite abnormalities of the T helper/suppressor ratio, increased autoimmunity, as well as increased production of immune complexes. Silicone implants have been used in cosmetic and reconstructive surgery more than 30 years (Brown et al., 1960). The gel used in the implant is produced from silicone, which is then related with methyl chloride and polymerized to form stable polydimethylsiloxane (Brown, et al., 1960). There have been a number of reports describing the occurrence of connective tissue disease in patients after the implantation of silicone.(ABSTRACT TRUNCATED AT 400 WORDS)

Cellular Basis for Rheumatoid Inflammation

Rheumatoid arthritis (RA) is a chronic idiopathic disease characterized by persistent inflammation of the synovium, local destruction of bone and cartilage, and a variety of systemic manifestations. Although the etiologic stimulus has not been identified, rheumatoid synovitis is characterized by persistent immunologic activity, with CD4(+)/CD29(+) memory T cells prominently involved. Many of the local and systemic manifestations of RA appear to result from the production of a variety of cytokines within the inflamed synovium. A number of other inflammatory mediators produced in the rheumatoid synovium, including arachidonic acid metabolites, vasoactive amines, platelet-activating factor, and complement cleavage products contribute to the inflammatory process. In addition, the local production of immunoglobulin and the autoantibody, rheumatoid factor, along with the local production of immune complexes and complement activation, play a major role in the destructive potential of rheumatoid synovitis. The driving force behind rheumatoid inflammation, however, is likely to be CD4(+) T cells responding to an antigenic epitope in the synovium in an HLA-DR restricted manner. Understanding the immunopathogenic process underlying rheumatoid inflammation should provide insight into approaches to control the disease effectively and specifically.