HJV gene mutations in European patients with juvenile hemochromatosis.

A large variety of mutations within the genes encoding hepcidin (HAMP) and hemojuvelin (HJV) have been identified in patients with the severe iron overload disorder juvenile hemochromatosis (JH). The aim of the present study was to evaluate the molecular background of JH in patients from central parts of Europe. Sequence analyses of HAMP and HJV were performed in seven JH patients from six families from Germany, Slovakia, and Croatia. For detection of the G320V mutation in HJV, a rapid polymerase chain reaction-based assay was developed. No mutations were found within the HAMP gene. Six of seven (86%) JH patients carried at least one copy of the G320V mutation within the HJV gene. Four of these patients were homozygous for the G320V mutation. In addition, two novel HJV mutations were identified (C119F and S328fsX337). Taken together, the present study demonstrates that molecular analysis of the HJV gene is a powerful tool for an early and reliable diagnosis of JH. As in affected patients from Greece, the G320V mutation seems to be widely distributed among JH patients from central parts of Europe. Therefore, detection of the G320V mutation could identify the majority of JH cases from these regions non-invasively.

[Analysis of immunoglobulins and complement factors in synovial fluid and serum in rheumatoid arthritis, seronegative spondyloarthropathies and osteoarthritis: pathophysiology and retrospective analysis of clinical value]. / Analyse der Immunglobuline und Komplementfaktoren in Synovialflüssigkeit und Serum bei rheumatoider Arthritis, seronegativen Spondylarthropathien und Osteoarthritis: Pathophysiologie und retrospektive Analyse der klinischen Wertigkeit.

UNLABELLED: Synovial fluid (SF) analysis was a mandatory investigation in rheumatological practice. In recent time, synovial fluid analysis lost importance predominantly due to unclear defined guidelines for the practical use. OBJECTIVE: To evaluate the clinical value of the determination of the complement components C'3c and C'4 and immunoglobulines IgG, IgA and IgM synovial fluid concentrations with regard to pathophysiology and currently used RA and SpA classification criteria. METHODS: Synovial fluid samples were obtained from 22 patients fulfilling ACR criteria for rheumatoid arthritis (RA), and 18 patients suffering from seronegative spondyloarthropathy (SpA) according to the ESSG criteria. Sixteen osteoarthritis (OA) SF samples were used as controls. IgG, IgA, IgM, C'3c and C'4 in SF and sera were determined by nephelometry. Comparison of the diseases, and linear as well as stepwise logistic regression analyses were performed in order to determine the interrelation of the determined parameters and a ranking of their diagnostic value for the identification of RA or SpA synovial fluids. RESULTS: SF-IgA, SF-IgG and SF-IgM concentrations were closely correlated with their corresponding serum levels (p < 0.01), while SF-C'3c and SF-C'4 depended on articular factors (p < 0.01). Determination of SF-C'3c (accuracy = 80.4%, improved chi 2 = 22.02, p < 0.001) and SF-C'4 (accuracy = 75.0%, improved chi 2 = 21.81, p < 0.001) both provided a good predictive value for the diagnosis of SpA when exceeding the cut off level of about 40 mg/dl (C'3c) or 15 mg/dl (C'4), respectively. Calculation of the C'-SF/S ratios did not provide an additional diagnostic benefit. SF-IgG, IgA and IgM as well as the calculated SF/S ratios were within the same range in RA and SpA fluids. CONCLUSIONS: SF concentration of complement components primarily depends on local articular factors. Significant differences of SF complement concentrations in established RA and SpA give reason for prospective analysis of these parameters in early undifferentiated oligoarthritis and evaluation in large studies, e.g. when re-evaluating the preliminary criteria for spondyloarthropathy.

IgA and IgG autoantibodies against alpha-fodrin as markers for Sjögren's syndrome. Systemic lupus erythematosus.

OBJECTIVE: To determine the prevalence of IgA and IgG autoantibodies against alpha-fodrin in patients with primary and secondary Sjögren's syndrome (SS) and controls. METHODS: An ELISA detecting IgA and IgG antibodies against alpha-fodrin was developed. We examined the prevalence of IgA and IgG antibodies against alpha-fodrin in patients with primary and secondary SS, systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA) and blood donors. RESULTS: IgA antibodies against alpha-fodrin were detected in 64% of patients with primary SS (n = 85), 47% of patients with secondary SS and SLE (n = 15), and 86% of patients with secondary SS and RA (n = 7). IgA autoantibodies against alpha-fodrin were detected in only one of 160 sera obtained from blood donors and in one of 50 and 2 of 12 sera obtained from SLE and RA patients without sicca syndrome, respectively. The prevalence of IgG antibodies against alpha-fodrin in SS was lower: they were detected in 55% of sera obtained from patients with primary SS, 40% of patients with secondary SS and SLE, and in 43% of patients with secondary SS and RA. Three of 160 sera from blood donors and one of 50 and 5 of 12 sera from SLE and RA patients without sicca syndrome, respectively, contained IgG antibodies against alpha-fodrin. CONCLUSION: IgA rather than IgG antibodies against alpha-fodrin are specific for and frequently observed in primary and secondary SS and are useful markers for this autoimmune disorder.

Iron-overload and genotypic expression of HFE mutations H63D/C282Y and transferrin receptor Hin6I and BanI polymorphism in german patients with hereditary haemochromatosis.

Gene variations of HFE, a HLA-class I like molecule, are highly associated with hereditary haemochromatosis (HH). Functional as well as molecular studies of the HFE protein have indicated that the molecule is involved in iron metabolism and that the HFE gene variations observed among HH patients affect its interaction with the transferrin receptor (TfR). In the present study, we have therefore analysed the relationship between the HFE gene variants, C282Y and H63D, and body iron status among 85 German HH patients. In addition, two TfR gene polymorphism, TfR-Hin6I and TfR-BanI, were typed that have been reported to define ethnically distinct haplotypes. As controls we used 251/159 healthy German blood donors. Seventy-eight (92%) patients were C292Y homozygous, the H63D mutation was present in five (6%) patients with none of the patients being H63D homozygous. Serum transferrin, transferrin saturation and liver iron content were determined prior to therapeutic intervention. Among C282Y homozygous patients serum ferritin levels (2294 +/- 3174 vs. 463 +/- 224 microg L-1, P < 0.0001) and transferrin saturation (86 +/- 18% vs. 62 +/- 25%, P = 0.048) were elevated significantly compared with C282Y and/or H63D heterozygous patients. In addition, the liver iron content (291 +/- 165 vs. 138 +/- 95 micromol g-1, P = 0.028) and liver iron index (6.4 +/- 2.8 vs. 3.2 +/- 2.3, P = 0.019) were increased among C282Y homozygotes compared with C282Y heterozygotes. In contrast, no difference was observed between patients and controls regarding the distribution of TfR-Hin6I and TfR-BanI alleles. These data indicate that the iron intake is higher among C282Y homozygous patients compared with C282Y heterozygous or C282Y/H63D compound heterozygous individuals and supports the functional role of the HFE protein in iron metabolism whereas the TfR gene variants seem to have no influence on iron uptake.