Anna Horváth

Relationship of Anti-60 kDa Heat Shock Protein and Anti-Cholesterol Antibodies to Cardiovascular Events

Background—Several recent studies have indicated an association between key inflammatory mediators and atherosclerotic diseases. We evaluated whether high levels of antibodies against heat shock proteins and cholesterol (ACHA) predicted cardiovascular (CV) events. Methods and Results—We used blood samples from the Heart Outcomes Prevention Evaluation (HOPE) study to conduct a nested case-control study of 386 cases with CV events and 386 age- and sex-matched HOPE study controls without events. We explored the relationship between anti-hsp antibodies, ACHA, and subsequent outcomes (incident myocardial infarction, stroke, or CV death) during a mean follow-up of 4.5 years using conditional logistic regression. High levels of anti-hsp65 antibodies (≥90th percentile) predicted CV events (OR, 2.1; 95% CI, 1.2 to 3.9, P =0.01). Anti-hsp60 antibodies did not predict any event type, whereas incident stroke developed significantly less frequently in patients with high ACHA levels. Anti-hsp antibodies and ACHA did not correlate with inflammatory (fibrinogen, C-reactive protein, interleukin-6, intracellular adhesion molecule-1) or infectious markers (C pneumoniae or cytomegalovirus antibodies). Anti-hsp65 antibodies (≥90th percentile) and fibrinogen (highest tertile) had a strong joint effect: patients with high concentrations of both had more CV events (OR, 5.5; 95% CI, 1.8 to 17.5, P =0.004) than patients with low levels of both. A similar joint effect (OR, 2.7; 95% CI, 1.3 to 5.7, P =0.01) was found for high levels of anti-hsp65 and presence of cytomegalovirus antibodies. Conclusions—Serum antibodies to hsp65 were associated with subsequent CV events in this study of high-risk patients, independent of conventional cardiovascular risk factors and other inflammatory markers.

Helicobacter pylori Infection in Connective Tissue Disorders is Associated with High Levels of Antibodies to Mycobacterial hsp65 but not to Human hsp60

Background. To investigate whether the Helicobacter pylori status influences levels of antibodies against mycobacterial heat shock protein (hsp) 65 and human hsp60 in systemic autoimmune diseases and to study the concentration of anti‐H. pylori antibodies in autoimmune patients and healthy controls.

Novel anti-cholesterol monoclonal immunoglobulin G antibodies as probes and potential modulators of membrane raft-dependent immune functions.

Natural autoantibodies against cholesterol are present in the sera of all healthy individuals; their function, production, and regulation, however, are still unclear. Here, we managed to produce two monoclonal anti-cholesterol antibodies (ACHAs) by immunizing mice with cholesterol-rich liposomes. The new ACHAs were specific to cholesterol and to some structurally closely related 3β-hydroxyl sterols, and they reacted with human lipoproteins VLDL, LDL, and HDL. They bound, usually with low avidity, to live human or murine lymphocyte and monocyte-macrophage cell lines, which was enhanced substantially by a moderate papain digestion of the cell surface, removing some protruding extracellular protein domains. Cell-bound ACHAs strongly colocalized with markers of cholesterol-rich lipid rafts and caveolae at the cell surface and intracellularly with markers of the endoplasmic reticulum and Golgi complex. These data suggest that these IgG ACHAs may serve as probes of clustered cholesterol (e.g., different lipid rafts) in live cells and thus may also have immunomodulatory potential.

Anti-cholesterol antibodies (ACHA) in patients with different atherosclerotic vascular diseases and healthy individuals. Characterization of human ACHA

In animal experiments the protective role of anti-cholesterol antibodies (ACHA) in the development of atherosclerosis has been demonstrated. Despite the fact that ACHA are present in the serum of healthy humans, no data on the occurrence of these antibodies in human diseases are available. We determined serum concentrations of IgG type ACHA by an enzyme immunosorbent assay in 600 patients with atherosclerotic vascular diseases (86 patients with peripheral occlusive atherosclerosis, 146 patients with cerebrovascular diseases, 341 patients with severe coronary heart disease (CHD) who received aorto-coronary by-pass, 27 patients with myocardial infarction who did not undergo by-pass operation), in 57 patient controls (complaints of CHD, without coronarographic alterations) and in 218 healthy individuals. ACHA were present in the sera of all persons tested. No serum cofactor is needed for the binding of human ACHA to solid phase cholesterol, binding can be inhibited dose-dependently by LDL and even more strongly with LDL/VLDL preparations purified from human serum. ACHA levels were found to be considerably lower in patients with peripheral occlusive atherosclerosis and cerebrovascular diseases compared with the levels in healthy individuals. By contrast, the ACHA levels of patients with CHD were considerably higher. No differences in the IgG subclass distribution and binding efficiency of ACHA in the sera of CHD patients and controls were found. Thus, our present findings indicate that both low and high ACHA production may be associated with different atherosclerotic vascular diseases.

High Level of Anticholesterol Antibodies (ACHA) in HIV Patients. Normalization of Serum ACHA Concentration after Introduction of HAART

Anticholesterol antibodies (ACHA) are natural antibodies against the 3beta-OH group of cholesterol. Since lipid disorders are common in HIV infection and HAART may further enhance dislipidaemia, we determined by using an ELISA method serum ACHA concentrations in HIV patients and healthy HIV-seronegative controls. ACHA levels were almost 4 times higher in the sera of 46 patients than in 110 controls. No difference in the specificity of ACHA was found between HIV-seropositive and HIV-seronegative sera. Binding of ACHA to cholesterol-coated plates from a HIV-seropositive serum was dose-dependently inhibited by preincubation with HIV-1(BA-L) preparation. Serum concentration of ACHA was significantly higher in the patients with low serum cholesterol levels than in those with normal cholesterol levels. HAART induced a marked drop of ACHA concentration. We found a significant negative correlation between the length of HAART and the ACHA levels. By contrast, HAART did not significantly influence total IgG concentration and titers of antibodies against 60 kD heat shock protein. Our findings indicate that high levels of ACHA in HIV-infection may contribute to the development of hypocholesterolaemia frequently observed in this disease.

Anti-cholesterol antibodies in human sera.

In the last 30 years many research showed that high serum cholesterol level is a great risk for the atherosclerosis. In recent years, it has become clear that the immune system has a major role in atherosclerosis development and progression, and has binding capacity to cholesterol as well. It has been demonstrated in animal experiments, that anti-cholesterol antibodies (ACHA) can prevent cholesterol diet induced atherosclerosis. Our group is looking for the answer, whether ACHA have the same function in animals and in humans, or not. In this review we summarize our studies in human sera. We measured serum ACHA levels in different groups of patients with atherosclerotic diseases in patients with viral infections and in healthy population. In the summary we write about the possible functions of ACHA in the human immune system.

Serum Anti-cholesterol Antibodies in Chronic Hepatitis-C Patients During IFN-α-2b Treatment

Previously we detected more than 3 times higher anti-cholesterol antibody (ACHA) levels in HIV positive patients compared to healthy individuals, however, this level significantly decreased during highly active anti-retroviral therapy (HAART). In our present study we examined whether these findings could also be detected in patients with chronic hepatitis C (CHC). We calculated the correlation between the ACHA levels and the C5b-9 complement activation product. 39 patients with CHC were treated with IFN-alpha-2b (Schering-Plough) 5 MU daily for 6 weeks, followed by 5 MU TIW. Serum levels of ACHA and complement activation products were measured with ELISA. Serum HCV RNA was measured by a highly sensitive branched DNA technique before and 3, 6 and 12 months after the beginning of IFN-alpha-2b therapy. 52 healthy persons served as controls. At the onset of treatment ACHA level was significantly (p = 0.0062) higher in patients (40 (24-69) AU/ml) (median (interquartile range)) than in control sera (26 (20-35) AU/ml). In the 26 responder patients ACHA levels decreased to the normal level during the therapy, but no change was observed in the 13 non-responders. In patients with a sustained response ACHA levels remained low till the end of the 12 months IFN treatment. ACHA levels were significantly (p = 0.0422) higher in the patients with low ( or = 4.0 mmol/l) cholesterol concentrations. The ACHA level before the therapy strongly correlated (r = 0.5499, p = 0.0014) with C5b-9 serum levels. ACHA levels are elevated in CHC, but this elevation is not as high as in HIV. Decrease of viral load by IFN-alpha-2b treatment in the responders results in normalization of ACHA concentration. High ACHA levels in patients with low serum cholesterol concentration suggest that high ACHA levels may contribute to the decrease in cholesterol levels. The correlation between the ACHA and C5b-9 levels indicate, that the ACHA may play a role in the complement activation in CHC.

A nationwide study of the epidemiology of relapsing polychondritis

Objective Relapsing polychondritis (RP) is a rare autoimmune inflammatory disease that attacks mainly cartilaginous structures or causes serious damage in proteoglycan-rich structures (the eyes, heart, blood vessels, inner ear). This study shows results regarding the epidemiology, progression, and associations of this highly variable disease by collecting all cases from a 124-million-person-year Central European nationwide cohort. Methods We used the Hungarian Health Care Database to identify all persons with possible RP infection. We followed patients who had International Classification of Diseases 10th edition code M94.1 at least once in their inpatient or outpatient records between January 1, 2002 and December 31, 2013 in Hungary. We classified these patients into disease severity groups by their drug consumption patterns between January 1, 2010 and December 31, 2013. We analyzed the regional distribution of RP incidences as well. Overall maps of comorbidity are presented with network layouts. Results We identified 256 patients with RP among cumulatively 11.5 million registered inhabitants. We classified these patients into four severity classes as “extremely mild” (n=144), “mild” (n=22), “moderate” (n=41), and “severe” (n=4). Two additional groups were defined for patients without available drug data as “suspected only” (n=23) and “confirmed but unknown treatment” (n=22). The age and sex distributions of patients were similar to worldwide statistics. Indeed, the overall survival was good (95% confidence interval for 5 years was 83.6%–92.9% and for 10 years was 75.0%–88.3% which corresponds to the overall survival of the general population in Hungary), and the associations with other autoimmune disorders were high (56%) in Hungary. Almost any disease can occur with RP; however, the symptoms of chromosomal abnormalities are only incidental. Spondylosis can be a sign of the activation of RP, while Sjögren syndrome is the most frequent autoimmune association. Regional distribution of incidences suggests arsenic drinking water and sunlight exposure as possible triggering factors. Conclusion The good survival rate of RP in Hungary is probably associated with the early diagnosis of the disease.

Anti-cholesterol antibody levels in hereditary angioedema.

Hereditary angioedema (HAE) is a rare disorder caused by the deficiency of the C1‐inhibitor gene (C1INH) and characterized by recurrent bouts of angioedema. Autoimmune disorders frequently occur in HAE. Previously we found, that danazol has an adverse effect on serum lipid profile: reduced high‐density lipoprotein (HDL) and elevated low‐density lipoprotein (LDL) cholesterol levels are associated with long‐term prophylactic use, whereas total cholesterol levels are unchanged. Our aim was to study the anti‐cholesterol antibody (ACHA) production in HAE patients and compare it with those of healthy blood donors, and to investigate the possible associations between ACHA levels and serum lipid profile alterations caused by danazol. Anti‐cholesterol IgG levels were measured by ELISA and their correlation with serum concentrations of total cholesterol, HDL, LDL, triglycerides was determined in HAE patients receiving/not receiving danazol. Serum ACHA levels were significantly higher in HAE patients, compared to healthy blood donors (P < 0.0001). Longterm danazol prophylaxis had no effect on serum ACHA levels in HAE patients. However, we found a significant, negative correlation between ACHA levels and serum total cholesterol (r =−0.4033, P = 0.0200), LDL (r =−0.4565, P = 0.0076) and triglyceride (r =−0.4230, P = 0.0121) levels only in danazol‐treated patients, but not in HAE patients who did not receive long‐term prophylaxis. Patients with HAE have higher baseline ACHA levels compared to healthy subjects, and this might reflect polyclonal B‐cell activation. The latter would be a potential explanation for the lack of an increased incidence of infectious diseases in HAE patients, but might lead to increased autoimmunity.

Significant decrease of the enhancement/neutralization index in HIV patients during highly active antiretroviral therapy (HAART)

Authors studied the effect of highly active antiretroviral therapy (HAART) on balance of the antibodies that enhance or neutralize growth of HIV-1(IIIB) strain in MT-4 cells in the presence or absence of human complement. Sequential serum samples were collected from 28 patients in advanced stage of HIV disease before and during HAART. The balance of the enhancing and neutralizing antibodies was expressed by an index value (E/N I). Samples with an E/N I of <0.5 (twofold decrease in virus production) were considered as neutralizing, whereas samples with an E/N I>2.0 (twofold increase in virus production) were considered as enhancing. At the beginning of HAART serum samples from eight patients enhanced, and samples from only two patients neutralized the virus in the presence of complement, median (25th-75th percentile) value of E/N I was 1.32 (0.79-2.29). E/N I significantly (P<0.0001) dropped to 0.37 (0.19-0.57) during the follow-up period of 18.5 (10.5-23.5) months under HAART. Similar changes were detected when serum samples were tested with no complement added. The E/N I values were also markedly decreased when cultures inoculated with mixtures of HIV and purified IgG prepared from serum pools taken before and during HAART, respectively, were compared. In the last samples of 20/28 patients, neutralization was measured even in the presence of complement while enhancement was found with none of these samples. These findings suggest that HAART results in disappearance of enhancing antibodies and switches the E/N I toward neutralization.