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BACKGROUND & AIMS: The extremely high rate of chronicity to hepatitis C virus (HVC) infection suggests an inefficient immune response. The humoral immune response to HCV was evaluated in 60 patients with chronic HCV infection and in 12 patients acutely infected with HCV. METHODS: A number of recombinant HCV antigens including the core, envelope 2 (E2), nonstructural (NS) 3, NS4, and NS5 proteins, and NS4a and E2-HVR-1 peptides were used in enzyme-linked immunoassays. RESULTS: Immunoglobulin (Ig) G antibody responses to these viral antigens, except for the HCV core, were highly restricted to the IgG1 isotype. The prevalence of antibodies of the IgG1 isotype specific for the HCV core, E2, E2-HVR1, NS3 (helicase domain), NS4, and NS5 antigens was 97%, 98%, 28%, 88%, 33%, and 68%, respectively. Antibodies of the IgG3 isotype specific for E2, E2-HVR-1, NS3, NS4, and NS5 were detected in a minority of serum samples. The IgG2 and IgG4 isotypes were rarely if ever detected. Furthermore, antibody responses to HCV viral antigens were of relatively low titer and, with the exception of anti-HCV core, were delayed in appearance until the chronic phase of infection. CONCLUSIONS: The IgG1 restriction, low titer, and delayed appearance of antibody responses elicited during HCV infection suggest that the immunogenicity of HCV proteins is limited in the context of natural infection. Inasmuch as recombinant HCV viral antigens perform as relatively normal immunogens in small animals, we suggest that the defective humoral immune responses during HCV infection may be attributable to an "immune avoidance" strategy.  相似文献   

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BACKGROUND: The aim of this study is to assess the prevalence of Parvovirus B19 infection in a group of patients affected by congenital coagulation disorders and its association with epidemiological aspects. PATIENTS AND METHODS: We have analyzed a group of 50 patients (median age 28) diagnosed with haemophilia or any other congenital coagulation disorder and 111 healthy non-transfused controls (median age 30) for IgG and IgM antibodies to Parvovirus B19 (Dako A/S, Glostrup, Dinamarca). Other issues analysed were HIV coinfection, the use of virally inactivated or non-inactivated plasma products and clinical symptoms of the infection. RESULTS: 84% of the patients (93.3% of those previously transfused) and 60.3% of the controls subjects showed IgG antibodies against Parvovirus B19. None of them had specific IgM antibodies. Five patients (all of them seronegative) had never been exposed to any plasma derivative and 11 were HIV-positive. The differences found between the prevalence of parvoviral infection in patients and controls are statistically significant, but those differences are only confirmed in younger patients (< 30) when age groups are compared. However, the severity of the haemostatic disorder, the type of plasma products infused or HIV coinfection had no influence on prevalence rates. The infection was clinically asymptomatic in all the cases. CONCLUSIONS: Haemophilic patients of any age are exposed to a higher risk of Parvovirus B19 infection than general population, although this infection had no clinical relevance in our study. The use of virally inactivated factor concentrates or the severity of the haemostatic disorder has no influence on this infectious risk.  相似文献   

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Leukocytoclastic vasculitis is the dominant lesion of mixed cryoglobulinemia (MC). The high prevalence of antibodies to hepatitis C virus (HCV) in association with the higher concentration of HCV RNA genomic sequences in the cryoglobulins suggests a close relationship between MC and HCV infection and strongly supports the view that this virus plays a key role in causing vascular damage. Analysis of the composition of immune complexes (ICs) provides evidence that cryoglobulins include virions mostly bound to IgG that is specifically reactive with HCV-related proteins, which in turn are crosslinked by monoclonal IgM with rheumatoid factor (RF) activity, frequently bearing the WA crossidiotype (XId). This structure is similar (if not identical) to that of circulating ICs from HCV-infected patients without cryoglobulins, suggesting that the virus may be directly responsible for the production of WA RF. Evidence for the role of circulating cryoproteins in the pathogenesis of cutaneous and renal vasculitis stems from the demonstration of HCV-related proteins and/or HCV RNA genomic sequences in the vessel wall of patients with MC. Our data indicate that endothelial cells are fully susceptible to infection by and replication of HCV, and support the contention that they serve as sufficient targets for the binding of HCV proteins expressed on the cell surface to serum immunoglobulins. The in situ demonstration of IgM RF WA XId adds further evidence that RF of the WA group participates in the development of vasculitis and probably stabilizes the binding of IgG antibodies. Lymphocytes may be crucial in the infection of endothelial cells by acting as a circulating viral reservoir. After encouraging initial results, controlled trials have defined the substantive efficacy of IFN-alpha in the treatment of MC. A response of IFN can be achieved in more than 50% of patients and includes improvement of cutaneous vasculitis and renal function. This clinical response is accompanied by a reduction in hepatitis C viremia, serum cryoglobulin concentration, and IgM RF synthesis. However, almost 80% of responders eventually have a clinical and biochemical relapse. Additional studies are required to improve the outcome and extension of this therapy, define the best candidates, and indicate the situations in which it is needed.  相似文献   

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We investigated the pathogenetic relevance of hepatitis C virus (HCV) infection in mixed cryoglobulinemia (MC) with or without complicating B-cell Non-Hodgkin's lymphoma (NHL) in comparison with other immunological and lymphoproliferative disorders. The following groups of patients were studied: A) 25 patients with MC in 7 cases evolved into B-cell NHL; B) 25 healthy subjects; C) 22 patients with different systemic immune diseases; D) 24 patients with chronic HCV infection without MC; E) 25 patients with B-cell idiopathic NHL. Methods used included: i) Polymerase chain reaction (PCR) for HCV RNA detection in serum and peripheral blood mononuclear cells (PBMC) (uncultured or mitogen-stimulated); ii) Branched DNA (b-DNA) for HCV RNA quantification; iii) HCV genotyping by genotype-specific primers localized in the core region and by hybridization of amplification products of the 5' untranslated region (5'UTR), obtained with universal primers, using genotype-specific probes. Serum anti-HCV and HCV RNA were detected in 88% and 73% of MC patients, respectively, and in a significantly lower percentage of healthy controls and patients with autoimmune diseases. HCV RNA concentration was significantly lower in supernatants than in corresponding whole sera (p < 0.001). Plus-strand HCV RNA was detected in 81% of peripheral blood mononuclear cell (PBMC) samples and minus-strand in the majority of fresh or mitogen stimulated cells. All MC patients with NHL had HCV RNA sequences in PBMC. HCV genotype 2a/III was detected in MC patients with a prevalence that was significantly higher than in HCV infected patients without MC. Surprisingly, HCV markers (anti-HCV and/or HCV RNA) were found in 32% of patients with idiopathic NHL. These data suggest that HCV infection is involved in the pathogenesis of MC through both direct participation in the immune complex related vasculitis and by triggering the lymphoproliferative disorder underlying the disease. This latter disorder seems to be related to HCV lymphotropism which could also be responsible for the evolution of MC to malignant lymphoma. This study also suggests that HCV infection may be involved in the pathogenesis of idiopathic B-cell NHL through a similar pathogenetic mechanism.  相似文献   

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Chronic liver disease in polytransfused thalassemic patients is an important cause of morbidity and mortality. The genesis is multiform: haemosiderosis and virus infections, resulting from repeated transfusions, may play an important role. Since HAV infection could make greatly worse the prognosis, in order to evaluate the opportunity of the HAV vaccination in polytransfused thalassemic patients, we studied the prevalence of HAV infection by detection of anti HAV antibodies (IgG) (enzyme immunoassay competitive technique) in 75 thalassemic patients (36 males, 39 females, aged 21.1 +/- 9.6, mean +/- SD). Fourty-two patients (56%) were HCV positive with persistent increase of transaminases. Eight patients were HAV antibodies positive (10.6%); the prevalence was 2.7% in patients aged 1 to 19 years, 11.4% in patients aged 20-39 years and 100% over 40 years of age. No differences were observed between sexes. Five out of fourty-two patients HCV positive were HAV antibodies positive (11.9%). In conclusion, in order to reduce further the incidence of liver infections in polytransfused thalassemic patients, we recommend an active immunization for HAV.  相似文献   

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OBJECTIVE: To describe the clinical picture of arthritis in patients with chronic infection by hepatitis C virus (HCV). METHODS: Two patient populations were studied. Patients with arthritis and evidence of serum elevation of alanine aminotransferase (ALT) at the consultation were checked for HCV infection. A second group of 303 consecutive patients with rheumatoid arthritis (RA) were also checked for the presence of HCV antibodies. All patients attended the outpatient rheumatology unit of a tertiary care teaching hospital. Chronic HCV infection was determined by the presence of viral RNA in serum. A group of 315 first-time blood donors served as controls. RESULTS: Twenty-eight patients with arthritis and chronic HCV infection were identified. Seven fulfilled criteria for RA, psoriatic arthritis was found in one patient, systemic lupus erythematosus in one, gout in 2, chondrocalcinosis in 2, osteoarthritis in 7, and tenosynovitis in one. In 7 patients with a clinical picture of intermittent arthritis, a definitive diagnosis could not be made. In these patients, mixed cryoglobulinemia was present in 6/7 (86%), whereas mixed cryoglobulinemia was found in 6/21 (28%) of the other patients. Among patients with RA, 23 (7.6%) had HCV antibodies, and active infection by HCV was found in 7 (2.3%) patients. The prevalence of HCV antibodies in a blood donor population was 0.95%, significantly different (p<0.001; 95% CI 0.03, 0.10) compared to patients with RA. The distribution of antibodies determined by recombinant immunoblot analysis was similar (p = NS) between RA patients and blood donors with HCV antibodies. CONCLUSION: There is not a single clinical picture of arthritis in patients with chronic HCV infection. There is a well defined picture of arthritis associated with the presence of mixed cryoglobulinemia that consists of an intermittent, mono or oligoarticular, nondestructive arthritis affecting large and medium size joints. Although a high prevalence of HCV antibodies is suspected in patients with RA, its occurrence may be coincidental and its interpretation is difficult to determine from the data in this study.  相似文献   

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BACKGROUND: It is known that in patients with porphyria cutanea tarda (PCT) there is an increased prevalence of the hepatitis B virus (HBV) and the hepatitis C virus (HCV). The incidence of anti-HCV in PCT in our country is 21.7% in estimations by the second generation method, however, the incidence of HBV in PCT was not assessed so far. METHODS AND RESULTS: In 60 patients with PCT antigens and antibodies against HBV and HCV were assessed (by the anti-HCV third generation ELISA method) and in subjects with signs of HBV or HCV. HBV DNA and HCV RNA were assessed by the method of the polymerase chain reaction. PCT without detectable HBV or HCV infection was found in 45 subjects (68%). HBV infection only was confirmed in seven subjects (10.6%), however none of the patients had positive HBsAg in serum. All had only antibodies against HBV. HCV infection only was detected in seven patients (10.6%) and HBV and HCV co-infection also in seven patients (10.6%). In the group of patients with HBV and HCV co-infection there was not a single HBsAg positive subject. The mean ALT serum activity was significantly higher as compared with subjects with HBV or HCV infection only (p < 0.05) and the histological finding on liver biopsy was more serious. CONCLUSION: HBV (21%) and HCV (21%) infection participates significantly in the clinical picture of PCT. A special subgroup is formed by patients with PCT and HBV and HCV co-infection who have as a rule a higher ALT activity and more severe histological changes in the liver. The incidence of HBV and HCV infection in PCT in the Czech Republic is double as compared with Germany or Great Britain.  相似文献   

10.
The aim of this study was to determine the prevalence of hepatitis B surface antigen (HBsAg) in hospitalised children, as specific marker for hepatitis B virus (HBV) infection. Our study group consists of 517 children, 68 of them diagnosed with chronic hepatitis. For HBsAg determination we used an ELISA test (Labsystems); for some children we also tested by ELISA the following markers: the antibodies and anti-hepatitis C virus (HCV) antibodies. From 517 children 24.28% were HBSAg positive and 75% of children with chronic hepatitis were positive for the same marker. Almost 100% of chronic active hepatitis (CAH) patients was positive for HBSAg. CONCLUSIONS: 1. The prevalence of HBsAg was much higher as compared with the healthy population prevalence; it is a clear prove that HBV infection has an important role in chronic hepatitis appearance. 2. For all HBsAg positive patients, it is necessary to determine other markers like HBeAg-anti-HBe antibodies system as well as markers for other viral hepatitis (HDV, HCV). 3. The anti-HBV infection vaccine will reduce significantly the prevalence of HBV and HDV infections; 4. Biological molecular technique, like PCR will be necessary in our country, in the future, even the price is so high, to monitoring the IFN treatment for chronic infection as unique solution for these patients.  相似文献   

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OBJECTIVE: We aimed to assess the seroprevalence of HBV, HCV and HDV virus markers in multi-transfused patients from Cluj-Napoca. MATERIAL AND METHODS: Stored serum samples of 105 multi-transfused patients (25 children, 19 adults and 61 chronically hemodialyzed patients) have been tested for HBsAg, anti-HBs, total anti-HBc, anti-HCV, total anti-HDV by automated ELISA (Sanofi Diagnostics Pasteur kits). RESULTS: HVC infection has been observed in 4/25 (16%) children, 14/19 (74%) multi-transfused adults and 48/61 (79%) haemodialysis patients. 8/25 (32%) children, 17/19 (89%) adults and 47/61 (77%) haemodialysis patients had HBV infection markers. Anti-HDV have not been found in HBV infected multi-transfused children and adults, respectively. Only 2/47 (4.25%) HBV infected haemodialysis patients had HDV infection markers. The prevalence of double infection (HCV and HBV) was high (4%, 84.2% and 67.2% in children, adults and haemodialysis patients). The prevalence of viral hepatitis markers correlated to the amount of transfused blood, and in haemodialysis patients also correlated to the duration on dialysis. CONCLUSIONS: In multi-transfused patients from Cluj area, the prevalence of viral hepatitis markers is high. The double infection (HCV and HBV) is frequent, especially in adults. The prevalence of HDV infection markers in HBV infected patients is low, in contrast with previously reported results.  相似文献   

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The prevalence of hepatitis C virus (HCV) infection increases with advancing age, but the disease has been poorly studied in the elderly. A population-based study was therefore carried out to investigate the prevalence of HCV infection and the severity of HCV-related chronic liver disease in the elderly. One thousand and sixty-three people (> or = 60 years of age) were screened for antibodies to HCV (anti-HCV) and for possible abnormalities of common liver function tests. Positive subjects and sex and age-matched anti-HCV-negative controls were recalled 12 months later for measurements of liver enzymes, confirmatory testing of anti-HCV, HCV RNA analysis and HCV genotyping. All subjects answered a specific questionnaire concerning medical history and possible risk factors. Forty-four subjects were positive for anit-HCV, the prevalence being 4.1%. Thirty-five positive subjects and 35 controls were investigated further. Risk factors for acquiring HCV were found to be: blood transfusion, surgical intervention and the use of non-disposable syringes. Abnormal alanine aminotransferase levels were found in 13 patients (37.1%). HCV RNA genotyping showed type 1b in three (15.8%), type 2a in 13 (68.4%) and not classified in three (15.8%) patients. There was no relationship between abnormalities of serum aminotransferase, the rate of HCV RNA positivity and HCV genotypes. Ultrasound abnormalities were present in 13 (37.1%) patients. In this elderly population the relatively high prevalence of HCV infection was thought to be caused by previous parenteral exposure. The low incidence of liver disease could be related to the prevalence of HCV genotype 2a in the majority of these patients, and hints at the possibility of an HCV carrier state in elderly individuals.  相似文献   

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We evaluated in a series of 33 HCV positive (both RT-PCR and HCV RIBA 2 assays) B cell non-Hodgkin's lymphomas (NHL) patients the prevalence of active and inactive HGV infection by HGV RNA assays (RT-PCR) and anti HGV antibodies directed against E2 structural protein (immunoenzimatic method), a reliable serologic marker of past HGV infection followed by viral clearance. We found only one patient with HGV positivity at RT-PCR (3%). Twenty-six of 33 patients were positive for anti HGV/E2 antibodies (78.8%) suggesting past infection. If confirmed, our preliminary data seem to suggest a higher incidence of HGV past infection in our group of HCV positive patients with B cell NHL.  相似文献   

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The prevalence of Helicobacter pylori (HP) IgG antibodies was analysed in a group of 142 asymptomatic children (group A) and in 31 pediatric patients (group B) with recurrent abdominal pain. HP IgG antibodies were measured by a commercially available fluorescence-enzyme immuno-assay test (Heloritest IgG, Fa Eurospital). In asymptomatic children the prevalence of HP IgG antibodies increased significantly with age from 17% with 6 years to more then 40% with 14 years. A higher prevalence of HP IgG antibodies was found in children living in more crowded housing conditions. Comparing the number of HP IgG positive children in group B (58%) to a matched population from group A (35%) no statistically different prevalence rates were found. Thus HP IgG antibodies are found in similar frequencies, in both, symptomatic and asymptomatic children. Therefore the presence of HP-IgG antibodies does not necessarily indicate that the HP infection is the cause for the recurrent abdominal pain in these children.  相似文献   

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In 1994 the first human parvovirus B19 (B19) epidemic to be documented in Denmark was recorded from February 2 to September 30. In total, 10,333 serum samples were tested for specific B19 IgM and IgG antibodies, using IDEIA Parvovirus B19 IgM and IgG kits. The prevalence of B19 IgM positivity was 11% for the whole period and 29% at the peak of the epidemic in week 14, declining from week 39 and onwards to 1-3%. The prevalence of B19 IgG (IgM-negative samples) was 60%, indicating an earlier infection, and the same for men and women. The gender distribution of tested patients was the same at the beginning of the epidemic as at the end of the epidemic and a year after its peak, i.e. 86% of samples were from women and only 14% from men. Age distribution for women was the same for the three periods (median age 34 years). For men the median age was 32 years, 39 years and 31 years, respectively. Only a few samples from children were tested. No change in test pattern was observed during the three periods. Approximately 75% of all samples tested were from women of childbearing age (18-45 years old), suggesting a fear of fetal complications in an actual or future pregnancy, rather than a serological verification of clinical symptoms. From the sparse clinical information that accompanied the serum sample we were not able to demonstrate that women were more likely than men to have a symptomatic B19 infection. With reservations we estimate that 14% of adverse pregnancy outcome is correlated with a B19 infection.  相似文献   

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OBJECTIVE: The purpose of this retrospective survey was to determine the prevalence and outcome of hepatitis C virus (HCV) infection in cirrhotic patients undergoing liver transplantation (OLT) in Spain in 1992. METHODS: Post-OLT HCV infection was defined by anti-HCV (second-generation ELISA) and/or PCR. Patients were divided into groups A (HCV-positive pre-OLT: n = 124, 46%) and B (HCV-negative pre-OLT: n = 145, 54%). RESULTS: HCV infection was more prevalent in patients originally diagnosed as having non-A non-B cirrhosis (97%) and cryptogenic cirrhosis (79%) than in patients with cholestatic or metabolic diseases. Group A patients were older (53.3+/-7.9 versus 47.6+/-9.7; P< 0.05) and had a higher prevalence of hepatocellular carcinoma (22% versus 4%, P< 0.05). Post-OLT HCV infection was 99% in group A versus 4% in group B (P< 0.05). Histological hepatitis developed in 39% (66% in group A versus 14% in group B, P< 0.05) with similar follow-up. Chronic rejection occurred in 6% (3% in group A versus 8.5% in group B, P= 0.07). Retransplantation rate (overall 8%) and two-year patient survival did not differ between groups (79% versus 72%). Graft survival was higher in group A (74% versus 65% at 2 years, P= 0.04). CONCLUSIONS: HCV-cirrhosis represented the most frequent indication for OLT in Spain in 1992. While HCV recurrence was universal, de novo acquisition was rare. HCV accounted for most post-OLT hepatitis (87%), but was not associated with chronic rejection, nor with a higher retransplantation rate. Patient survival was not different in HCV patients compared to a control group after a follow-up of 2-3 years. Therefore, at present, HCV-cirrhosis is an acceptable indication for OLT.  相似文献   

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Clonal rearrangements of Ig heavy chain (IgH) genes and hepatitis C virus (HCV) genomic sequences were assayed on intrahepatic B lymphocytes isolated from HCV chronically infected patients with and without type II mixed cryoglobulinemia (MC). Liver tissue samples from eight patients with and nine without MC were subjected to routine histologic studies, immunophenotyping, and genotypic analysis including IgH V-D-J region gene rearrangements by PCR. RT-PCR, signal amplification by branched DNA assay, and in situ hybridization technique were used to detect and quantitate HCV RNA genomic sequences in selected B cells purified from each tissue sample. Although HCV infection of intrahepatic B cells was shown in all patients both with and without MC, frank B cell monoclonal and oligoclonal patterns were found in only three and four patients with MC, respectively. No monoclonal profile was seen in the noncryoglobulinemic patients, whereas an oligoclonal profile was demonstrated in four of them. No clonalities were shown in HCV-unrelated patients matched for age and severity of liver disease. No obvious difference in HCV genotype distribution was found in relation to the clonal expansion profile. Noncryoglobulinemic patients showing clonal expansion in liver tissue had higher titers of serum rheumatoid factor (RF). Spontaneous production of RF was shown in cell cultures of intrahepatic B cells, suggesting their persistent stimulation in vivo. These data indicate that HCV infection of B cells and B cell clonal expansions occur in the liver microenvironment and preferentially involve RF-producing cells.  相似文献   

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OBJECTIVE: To investigate whether determining the presence of serum or synovial fluid (SF) IgG and IgA of anti-Chlamydia antibodies with two recent commercially available enzyme-linked immunosorbent assays (ELISA) using synthetic peptides or recombinant antigen could be helpful to detect possible Chlamydia trachomatis (CT)-involved disease in rheumatological patients without evidence of urogenital CT infection. METHODS: The prevalence of such antibodies was determined in samples from patients with well-defined disease, i.e. CT sexually acquired arthritis and from patients with other inflammatory arthropathies unrelated to CT. RESULTS: When considering IgG and/or IgA anti-MOMP or anti-LPS antibodies, a sensitivity of 100% was obtained for serum and SF samples, but with a low specificity. A sensitivity and a specificity equal or close to 80% were observed for the SF IgG anti-MOMP antibodies. CONCLUSION: Clinically, the most appropriate determination was the SF IgG anti-MOMP antibodies. This commercially available ELISA test could be useful for the diagnosis of probable CT reactive arthritis.  相似文献   

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OBJECTIVES: The aim of the study was to determine the prevalence and clinical significance of antibodies to individual histone components in systemic sclerosis (SSc). METHODS: Serum samples from patients with limited cutaneous SSc (lSSc; n = 42) and diffuse cutaneous SSc (dSSc; n = 28) were examined for IgG and/or IgM antibodies to individual histone components and complexes by enzyme linked immunosorbent assay (ELISA). RESULTS: The level of IgG antibody to total histones was significantly higher in lSSc and dSSc than in normal controls. The level of IgM antibody to total histones was significantly higher in lSSc, but not in dSSc, than in normal controls. IgG antibody to total histones tended to be increased in dSSc when compared with that in lSSc. On the other hand, IgM antibody to total histones tended to be increased in lSSc when compared with that in dSSc. Although SSc showed various antihistone specificities, H2B, H2A-H2B, (H2A-H2B)-dsDNA were main antigens recognised by IgG antibodies in both lSSc and dSSc. Although IgM antibodies to H2B and H2A-H2B were also detected in both lSSc and dSSc, serum samples from lSSc patients exhibited highest IgM reactivity with H1. CONCLUSION: SSc may be included among conditions in which heterogeneous antihistone antibodies are produced. IgM antibodies to the most accessible histone H1 may be related to mild clinical features (lSSc) and IgG antibodies to the inner core molecules of native histone such as H2B or complexes including H2B may be associated with severe clinical features (dSSc) in Ssc.  相似文献   

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