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PubMed1997

Chronic hepatitis C associated with anti-liver/kidney microsome-1 antibody is not a subgroup of autoimmune hepatitis.

To determine whether "autoimmune hepatitis type IIb" should be categorized as a subgroup of autoimmune hepatitis, we conducted a clinicopathological study of 25 adult Japanese patients who were positive for anti-liver/kidney microsome-1 (anti-LKM-1) anti-body and infected with the hepatitis C virus (HCV). Anti-LKM-1 was determined by indirect immunofluorescence and by the double immunodiffusion assays we have developed. Twenty-two patients did not present any unusual symptoms or any associated diseases during the course of their chronic HCV infection. The spectrum of HCV genotypes of these patients did not significantly differ from that of anti-LKM-1-negative Japanese patients with chronic hepatitis C. Histological examination of liver biopsy specimens showed the usual characteristics of chronic hepatitis C and lack of characteristics of autoimmune hepatitis type I. No disease-specific HLA haplotypes were noted, and HLA-DR4, which is detectable in 88.7% of Japanese patients with autoimmune hepatitis type I, was detected in only 50.0% of our group, the same rate as the background frequency. Prednisolone was effective in none of the six patients treated, but interferon was effective in six of ten treated patients (60%). From these results, we conclude that "autoimmune hepatitis type IIb" should not be categorized as autoimmune hepatitis, and that this subgroup is essentially chronic hepatitis C in which an autoantibody has been produced during the course of chronic HCV infection.

Adult↗

PubMed2000

[Masked autoimmune polyendocrine syndrome caused by sequelae of diabetes mellitus].

BACKGROUND: In most cases Type I diabetes is immunologically mediated. Complications after long duration of the disease are commonly observed. Further autoimmune mediated diseases are rare, but more often diagnosed in diabetics than in the general population. The combination of 2 autoimmune endocrinopathies is subsumed under the term autoimmune polyendocrine syndrome (APS). Depending on the endocrine gland involved disorders are classified as APS Type I, II or III. CASE REPORT: We report on a 64-year-old diabetic patient presenting with repeated nightly hypoglycemia. Diabetes was first diagnosed 12 years before. Clinical examination revealed a café-au-lait like color of the skin and severe peripheral polyneuropathy. Surprisingly, laboratory testing revealed a hemoglobin concentration of 6.8 g/dl. Further examinations led to the diagnosis of pernicious anemia and funicular myelosis. Screening for potentially associated autoimmune diseases showed also features of autoimmune thyroid disease. CONCLUSION: Despite of late manifestation of disease Type I diabetes should be considered if the clinical features correspond to an autoimmune induced disorder. Associated autoimmunopathies have always to be considered. Early diagnosis of commonly with diabetes associated autoimmunopathies can prevent as severe manifestations of disease as reported in this case.

Diabetes Mellitus, Type 1↗

PubMed2006

Regulatory T cells in human autoimmune diseases.

In the most simplistic terms, immune tolerance can be envisioned as a balance with autoreactive cells that arise naturally in all individuals on one side and regulatory mechanisms designed to counter those autoreactive processes on the other. A tilt of the balance toward the autoreactive side, either by increasing the number or function of autoreactive cells or by diminishing regulatory mechanisms, is manifested as autoimmunity. In contrast, tilting of the balance toward increased regulation could conceivably cause immunodeficiency. Regulatory T cells (T(REG)), and particularly the naturally arising CD4(+)CD25(+) subset of T(REG) cells, provide a substantial component of the autoimmune counterbalance. The identification of forkhead box P3 (FOXP3) as a critical determinant of CD4(+)CD25(+) T(REG) development and function has provided new opportunities and generated expanded interest in studying the delicate balance between autoimmunity and regulatory mechanisms in human autoimmune diseases. Identification of both human and mouse syndromes in which FOXP3 is mutated, and consequently CD4(+)CD25(+) T(REG) cells are absent, has led to a rapid accumulation of knowledge regarding T(REG) development and function over the past 5 years. The recent development of antibody reagents to specifically identify CD4(+)CD25(+) T(REG) cells by their FOXP3 expression has provided new tools to identify these elusive cells and investigate their role in human disease. This review will focus on the current state of knowledge regarding the role of T(REG) in human autoimmune diseases and on specific human immunodeficiencies that provide interesting models of autoimmunity.

Animals↗

PubMed2005

Complete obstruction of the lower common bile duct caused by autoimmune pancreatitis: is biliary reconstruction really necessary?

Recent observations suggest that an immune response is involved in the development of chronic pancreatitis. We report a case of autoimmune pancreatitis in a patient who showed complete obstruction of the lower common bile duct. A 63-year-old man was admitted to a local hospital, complaining of appetite loss and back pain. The patient had obstructive jaundice, and percutaneous transhepatic gallbladder drainage was performed. Fluorography through the biliary drainage catheter showed complete obstruction of the lower common bile duct. The patient had no history of alcohol consumption and no family history of pancreatic disease. Physical examination revealed an elastic hard mass palpable in the upper abdomen. Abdominal ultrasound and abdominal computed tomography (CT) scans showed enlargement of the pancreas head. While autoimmune pancreatitis was highly likely, due to the patient's high serum immunoglobulin level, the possibility of carcinoma of the pancreas and/or lower common bile duct could not be ruled out. Laparotomy was performed, and wedge biopsy samples from the pancreas head and body revealed severe chronic pancreatitis with infiltration of reactive lymphocytes, a finding which was compatible with autoimmune pancreatitis. Cholecystectomy and biliary reconstruction, using choledochojejunostomy, were performed, because the complete bile duct obstruction was considered to be irreversible, due to severe fibrosis. After the operation, prednisolone (30 mg/day) was given orally for 1 month, and the entire pancreas regressed to a normal size. Complete obstruction of the common bile duct caused by autoimmune pancreatitis has not been reported previously; this phenomenon provides an insight into autoimmune pancreatitis and provokes a controversy regarding whether biliary reconstruction is needed for the treatment of complete biliary obstruction caused by autoimmune pancreatitis.

Autoimmune Diseases↗

PubMed2002

Autoimmune pancreatitis starting as a localized form.

Autoimmune pancreatitis is a rare type of pancreatitis that is characterized by diffuse swelling of the pancreas and irregular stenosis of the pancreatic ductal system ("sclerosing" pantreatitis), caused by autoimmune processes. Previous reports have shown the complete form of the disease, but very few have presented follow-up imagings from the beginning to the complete form. We, herein, report a case of autoimmune pancreatitis starting as a localized form. A-56-year-old Japanese man developed obstructive jaundice. Ultrasonography showed a hypoechoic mass in the head of the pancreas, and endoscopic retrograde pancreatography (ERP) showed localized stenosis of the pancreatic duct in the head of the pancreas. Computed tomography (CT) showed enlargement, with a capsule-like rim, in the head of the pancreas. Internal biliary tube drainage was performed to relieve the obstructive jaundice. The patient was followed-up under the tentative diagnosis of localized "mass-forming" pancreatitis. Four months after the drainage, CT showed diffuse swelling of the pancreas, with a capsule-like rim, and ERP demonstrated diffuse irregular narrowing of the pancreatic duct. Glucose intolerance was noted for the first time. Steroid was given as a diagnostic treatment for autoimmune pancreatitis. Two months after initiation of the steroid treatment, the ERP findings were normal, and CT showed a normal pancreas. The biliary tube was removed, and the glucose intolerance was subsequently alleviated. To summarize, we report a case of autoimmune pancreatitis starting as localized "mass-forming" pancreatitis with a peripheral rim on imagings. It is very important to be well aware of the presence of the localized form of autoimmune pancreatitis.

Autoimmune Diseases↗

PubMed2003

Myasthenia gravis with thymoma and autoimmune haemolytic anaemia. A case report.

Myasthenia gravis is an autoimmune disorder that affects the neuromuscular junction and leads to weakness of the skeletal muscles. Associated autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis and pernicious anaemia are present in approximately 5% of the myasthenic patients. This report presents a 64-year-old man with autoimmune haemolytic anemia associated with myasthenia gravis and thymoma. The patient developed a severe Coomb's positive autoimmune haemolytic anaemia, which was resistant to treatment with large doses of prednisone. Haemolytic anaemia entered remission one month following thymectomy, and the patient has maintained a normal haemoglobin and a negative Coomb's test without the need for steroid or immunosuppressive therapy. In conclusion, thymectomy may induce a striking improvement of therapyresistant autoimmune haemolytic anemia in patients with MG and thymoma, but in terms of remission, a long follow-up is needed as autoimmune diseases can show spontaneous fluctuations.

Anemia, Hemolytic, Autoimmune↗

PubMed2005

Transplanted islets from lpr mice are resistant to autoimmune destruction in a model of streptozotocin-induced type I diabetes.

The mechanism by which beta-cells die during autoimmune diabetes has remained a subject of intense investigation. The loss of beta-cells in the disease is T cell mediated and thought to result from a number of different insults including apoptosis induction through the death receptor CD95. However, the role of CD95 in autoimmune diabetes, studied primarily in the non-obese diabetic (NOD) mouse model, has been controversial. We have used an alternative model of autoimmune diabetes triggered by repeated low doses of streptozotocin. In this model, islet grafts from C3H mice that carry the lpr mutation, and therefore lack the ability to undergo apoptosis through CD95-CD95L interaction, were completely protected when grafted in autoimmune diabetic mice despite periinsulitis (infiltration of T cells) which however did not progress to islet destruction. In contrast wild-type grafts were rapidly eliminated in autoimmune recipients. Our data provide strong support for a major role of CD95 in the destruction of islets in autoimmune mice.

Animals↗

PubMed1979

Autoimmune hemolytic anemia and carcinoma: an unusual association.

Four patients with Coombs'-positive hemolytic anemia associated with carcinoma are presented and compared to 12 previously described patients. These patients commonly seek medical attention for symptoms of anemia rather than for complaints due to the tumor mass. The physician should particularly evaluate for an underlying carcinoma when a patient over the age of 60 years presents with autoimmune hemolytic anemia. Autoimmune hemolytic disease has been demonstrated in patients with a wide variety of tumors, including squamous cell carcinomas, adenocarcinomas, hypernephromas, oat cell carcinomas and a seminoma. Corticosteroid treatment is less effective in autoimmune hemolytic disease associated with carcinoma than in idiopathic autoimmune hemolysis. Tumor extirpation in patients with localized neoplastic disease may abolish the autoimmune hemolytic anemia. Control of the carcinoma through irradiation and chemotherapy together with corticosteroid therapy and/or splenectomy lessened the anemia in some patients. The positive Coombs' test may revert to negative with tumor excision or control. Subsequently, the positivity of the Coombs' reaction may provide a clue to recurrent neoplastic activity. The pathogenic mechanism underlying the association between carcinoma and autoimmune hemolytic disease is poorly understood.

Adenocarcinoma↗

PubMed1992

HLA class II molecules and autoimmune hepatitis susceptibility in Japanese patients.

To investigate the association between autoimmune hepatitis and HLA alleles in Japanese patients, serological typing and class II genotyping were performed using the polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) method. Serological typing showed that HLA-B54, -DR4, -DR53, and -DQ4 were significantly more frequent in patients with autoimmune hepatitis than in controls. HLA-DR4 was most frequently associated with autoimmune hepatitis (88.7%). In PCR-RFLP typing, the frequency of DRB1*0405 was significantly higher in autoimmune hepatitis than in controls. However, there was no significant difference in the frequency of Dw between the patients and the controls who were DR4-positive. The significant increase observed in DQA1*0301 and DQB1*0401 was explained by a linkage disequilibrium with DR4. Six DR4-negative patients had DR2, but there was no significant difference in the frequency of the DR2-associated Dw-alleles compared with the DR2-positive controls. No DPB1 allele was significantly associated with autoimmune hepatitis. These findings suggest that the basic amino acid at position 13, which is present only on the DR2 and DR4 B1 molecules (Arg on DR2 and His on DR4), contributes to the susceptibility to autoimmune hepatitis among the Japanese.

Adult↗

PubMed1995

Pristane induces high titers of anti-Su and anti-nRNP/Sm autoantibodies in BALB/c mice. Quantitation by antigen capture ELISAs based on monospecific human autoimmune sera.

Autoantibodies to Su and anti-nRNP/Sm are common in human and murine systemic lupus erythematosus (SLE), and are also produced by BALB/c mice with SLE-like autoimmunity induced by pristane. Antigen capture ELISAs employing monospecific human autoimmune IgG were developed to quantitate the production of anti-Su and anti-nRNP/Sm autoantibodies in 77 sera from BALB/c mice with pristane-induced autoimmunity. The sensitivity and specificity of the anti-Su antigen capture ELISA were 100% compared with immunoprecipitation of 35S-labeled cellular proteins. All 16 immunoprecipitation positive sera were positive in the anti-nRNP/Sm antigen capture ELISA (100% sensitivity), whereas 55/61 immunoprecipitation negative sera were negative by ELISA (90% specificity). The 6/61 immunoprecipitation negative sera that were ELISA positive were probably true positives because subsequent sera obtained from the same mice were positive by both techniques. Thus, the antigen capture ELISA may be somewhat more sensitive than immunoprecipitation. The titers of anti-Su and anti-nRNP/Sm positive antibodies in the sera were as high as 1:25,000-1:250,000 by ELISA, suggesting that autoantibodies may be produced in pristane-primed BALB/c mice at levels comparable to those seen in spontaneous autoimmune disease. We conclude that antigen capture ELISAs based on human autoimmune sera were highly sensitive and specific for detecting murine anti-Su and anti-nRNP/Sm antibodies. This technique will be useful for quantitating antibodies in murine autoimmune disease models, since antigen capture ELISA avoids the use of denatured or recombinant antigens, permitting antibodies recognizing tertiary and quaternary structures to be detected.

Animals↗

PubMed1983

Effects of castration and sex hormones on immune clearance and autoimmune disease in MRL/Mp-lpr/lpr and MRL/Mp-+/+ mice.

The clearance of erythrocytes sensitized with IgG was studied in MRL/Mp-lpr/lpr (MRL-lpr) and MRL/Mp-+/+ (MRL-+/+) mice, which spontaneously develop autoimmune disease. In both strains, an age-dependent decline in clearance of IgG-sensitized erythrocytes was found. Impaired clearance occurred at an earlier age in MRL-lpr mice than in MRL-+/+ mice, correlating with the relative severity of autoimmune disease in these strains. Androgen treatment improved clearance in MRL-+/+ mice but not in MRL-lpr mice, even though autoantibody levels, renal function, and survival were improved. These results suggest that the beneficial effects of androgen on autoimmune disease are not due solely to improved clearance of immune complexes. Castration followed by estrogen administration did not influence immune clearance or autoimmune disease in MRL-lpr mice. These results indicate that impaired immune clearance is a common feature in several autoimmune mouse strains. However, the effects of sex hormones on immune clearance and autoimmune disease may be dissociated in some strains.

Animals↗

PubMed1989

Regulation of B cell activation in autoimmune mice.

These studies explore the regulation of immunoglobulin production in autoimmune mice. B cells were transferred from normal or autoimmune mice into H-2 compatible xid recipients. When transferred to autoimmune-prone xid mice, cells from either donor produced significant levels of autoantibody. Cells from the same animals transferred to normal xid recipients produced little autoantibody. An ELISA spot assay was then used to study the development of B cell repertoires in autoimmune animals. Young lupus-prone mice developed repertoires in which B cells reactive with both conventional antigens and autoantigens were simulated to a similar degree, a finding consistent with the influence of polyclonal B cell activation. To examine the effect of exogenously administered immune activators on the development of B cell repertoires, normal DBA/2 mice were stimulated with LPS or goat anti-mouse IgD. This led to a quantitative increase in the number of Ig-secreting cells and expression of a repertoire similar to that present in autoimmune mice. Immunization with a specific antigen induced a repertoire skewed toward reactivity against that antigen which did not resemble that present in autoimmune mice. These findings are consistent with the view that polyclonal activation contributes to the production of autoantibodies in early murine lupus.

Animals↗

PubMed1979

The effect of neonatal thymectomy on the induction of autoimmune orchitis in rats.

The objective of these experiments was to determine the effects of neonatal thymectomy on the induction of experimental autoimmune orchitis in inbred rats of the Fischer 344 and Lewis strains. It was found that thymectomy alone in Lewis rats, and thymectomy followed by immunization with testicular extract in both Lewis and Fischer 344 rats, led to the development of autoimmune orchitis, as indicated by decreased testes weights, increased serum spermagglutinating antibody titers and histopathological changes in the testes. These data indicate that rats of the Lewis strain are genetically predisposed to the development of autoimmune orchitis, and thymectomy alone leads to active manifestations of the disease, which are further enhanced by subsequent immunization with testicular extract. In Fischer 344 rats, thymectomy followed by immunization leads to indications of early signs of experimental autoimmune orchitis. This is in contrast to experimentally induced autoimmune diseases in other model systems, where previous investigators have reported that thymectomy lessens or prevents induction of autoimmune disease. It is suggested that these differences may be related to the timing of thymectomy with regard to differences in the time of appearance of sperm antigens (at puberty) as compared to pre-natal and early neonatal appearances of other autoantigens.

Animals↗

PubMed1992

Environmental enrichment, neocortical ectopias, and behavior in the autoimmune NZB mouse.

New Zealand Black (NZB) mice have severe autoimmune disease and approximately 40% have cortical ectopias in layer I of sensorimotor cortex. Because the ectopias are similar to those found in dyslexics, NZB mice have been used as an animal model for developmental learning disorders. In addition, these mice have been used as a model of learning deficits associated with autoimmune disease. To determine whether early intervention would affect learning processes in NZB mice, they were reared after weaning in standard cages or enriched environments. They were given a battery of behavioral tests to measure learning, laterality, and activity, after which they were sacrificed and their brains examined for cortical ectopias. The tests sorted into two behavioral sets. Ectopia-associated behaviors included black-white discrimination learning and the Morris spatial maze. As a group, the mice performed well on these tasks. Ectopic mice had poorer performance than non-ectopics on these measures, and environmental enrichment countered the effects of the ectopias. Autoimmune-associated behavior involved two-way avoidance learning in a shuttlebox. Mice were uniformely poor on this task, ectopias did not affect behavior, and environmental enrichment was without benefit. Evidence from this and other studies shows that poor shuttlebox performance is related to the presence of autoimmune disease. Thus, autoimmune disease and cortical ectopias each appear to affect a separate set of behavioral processes. Environmental enrichment is most effective for behavioral impairments mediated via cortical ectopias, but is much less effective, if at all, if autoimmunity is the primary mediator of the impairments.

Animals↗

PubMed1992

Secondary autoimmune diseases in herpes gestationis (pemphigoid gestationis).

BACKGROUND: Herpes gestationis (HG) is an autoimmune disease of the skin that occurs exclusively in association with pregnancy (or trophoblastic disease). It is associated with the HLA-DR3 and -DR4 antigens that are also associated with several other autoimmune diseases. HG has previously been reported in association with Graves' disease. OBJECTIVE: Our purpose was to determine the frequency of other autoimmune disease(s) in patients with a history of HG. METHODS: Seventy-five patients with a history of HG were studied for the frequency of other autoimmune diseases. RESULTS: We found an increased frequency of Graves' disease in patients with a history of HG. Those with HG have an increased risk for the development of other autoantibodies. There is an increased frequency of autoimmune diseases in the family members of patients with HG. CONCLUSION: Secondary autoimmune disease in HG is unusual, but does occur. The most frequent is Graves' disease.

Autoantibodies↗

PubMed1996

Autoimmune diseases in the pedigrees of schizophrenic and control subjects.

Autoimmune diseases aggregate in individuals and within pedigrees, and it has been postulated that autoimmune mechanisms may account for a proportion of schizophrenia. Structured questionnaires were used to interview the mothers of 121 DSM-III-R schizophrenic patients and the mothers of 116 controls in order to determine the prevalence of schizophrenia and of autoimmune diseases in their pedigrees. Patients with a schizophrenic first degree relative were significantly more likely to also have a parent or sibling with an autoimmune disease (60% vs. 20%, OR = 6.1, 95% CI = 2.3-6.5, p = 0.0003). A significant excess of insulin dependent diabetes mellitus (IDDM) was present in the parents and siblings of schizophrenic patients (OR = 9.65, 95% CI = 1.3-429.2, p = 0.009). These findings suggest that autoimmune mechanisms may play a role in the aetiology of schizophrenia, particularly familial schizophrenia. Associations have been established between autoimmune diseases and the HLA encoding genes of the major histocompatibility complex on chromosome six, and it may be that some of the genetic liability to schizophrenia involves these genes.

Adult↗

PubMed2004

Autoimmunity, anergy, lentiviral immunity and disease.

Autoimmune antibodies and autoimmune responses have been characterized in both human HIV infection and the rhesus macaque (RM) non-human primate model of SIV infection and reasoned to contribute to the pathogenesis of AIDS. Many theories for the induction and maintenance of such responses have been entertained including molecular mimicry between HIV proteins and self molecules, CD4+ T cell loss accompanied by loss of normal immune regulation that dictate self-non-self-reactivity, defective negative/positive selection of T cells to name a few. The precise mechanisms that lead to such immune dysfunction is difficult to study in humans. Our lab has been studying such autoimmune responses in both SIV-infected RM and sooty mangabeys (SM), a species from Africa that are naturally infected with SIV but do not display any detectable signs of immune deficiency or autoimmunity. We submit that this model is an important model since it allows for narrowing down those mechanisms and pathways that are a result of lentiviral infection per se from those that specifically cause disease including autoimmunity. During the course of these studies, we have ruled out a role for plasma and cellular viral loads, anti-viral humoral responses and a variety of cell signaling pathways. We have identified select pathways that appear to play roles in the pathogenesis of lentiviral infection and disease. These include pathways involved in innocent bystander killing by apoptosis of CD4+ T cells, role for differential regulation of the cell cycle, and a role for distinct host proteins that get incorporated by the virions as they are assembled and either bud out of CD4+ T cells or exit the cells in the form of multi-vesicular endosomal particles from monocytes/macrophages from SIV-infected disease susceptible RM and disease-resistant SM. We present our current working model and hypotheses that are designed to elucidate differences that are responsible for such distinct outcomes of lentiviral infection, autoimmunity and disease. We believe that such findings have important implications for the design of vaccines against human HIV infection.

Autoimmunity↗

PubMed2005

B-lymphocytes, innate immunity, and autoimmunity.

Having evolved to generate a huge Ag-specific repertoire and to mount T cell-dependent responses and long-term memory, the B lymphocyte is a central player in the adaptive branch of immune defense. However, accumulating evidence indicates that B-1 cells of the peritoneal cavity and marginal zone (MZ) B cells of the spleen also can play innate-like immune functions. Their anatomical locations allow frequent Ag encounter. Secreting essentially germline-encoded, polyreactive Abs, and responding rapidly and vigorously to stimulation, these two B cell subsets have evolved to impart potentially protective responses. With their additional capacities to secrete factors that can directly mediate microbial destruction and to express Toll-like receptors (TLR), B cells provide an important link between the innate and adaptive branches of the immune system. Currently, the relevance of these innate-like B cells to the pathogenesis of autoimmune disease is the focus of investigation. In experimental models of autoimmunity, the sequestration of autoreactive B cells in the MZ has been proposed to be essential for the maintenance of self-tolerance. The low activation threshold of MZ B cells makes them particularly reactive to high loads and/or altered self-Ags, potentially exacerbating autoimmune disease. Their expansion in autoimmune models and their association with autoantibody secretion indicate that they may participate in tissue damage. The demonstration that B cell depletion therapies may represent a highly beneficial therapeutic goal in autoimmune disorders suggests that specific elimination of B-1 and MZ B cells may represent a more efficient immunointervention strategy in systemic autoimmunity.

Animals↗