The functionally important IL-10 promoter polymorphism (-1082G-->A) is not a major genetic regulator in recurrent spontaneous abortions.

Enhanced secretion of anti-inflammatory Th2 cytokines is a characteristic feature in normal physiological pregnancy. In recurrent spontaneous abortions (RSA), however, defective production of interleukin-10 (IL-10) and other Th2 cytokines has been shown in humans. Association studies have shown that a base exchange polymorphism (guanine-->adenine) at position -1082 of the IL-10 promoter is associated with differential IL-10 production. Since factors contributing to IL-10 production appear to be important in RSA, we studied the IL-10 genotypes of 38 Finnish women with a history of three or more consecutive abortions and 131 ethnically matched healthy controls. No significant differences in the -1082 allele or genotype frequencies were found between the controls and the RSA women. The present study suggests that the IL-10 -1082 (G-->A) polymorphism is not a major genetic regulator in RSA.

HLA-DQA1 alleles and the presence of Helicobacter pylori antibodies.

Recent reports suggest that the HLA-DQA1 gene may be important in determining susceptibility to and outcome of Helicobacter pylori infection. To determine if there is an association between HLA-DQA1 alleles and H. pylori antibodies, DQA1 alleles and H. pylori-specific antibodies were determined in 199 random subjects of Finnish origin (mean age 43 years, range 22-69 years). H. pylori-specific class IgG antibodies were measured using the EIA method (Pyloriset-EIA-G, Orion Diagnostica, Espoo, Finland). HLA-DQA1 typing was carried out using PCR-SSP (PCR with sequence-specific primers). There were 64 subjects with H. pylori-specific class IgG antibodies (ab+) and 135 subjects without H. pylori-specific class IgG antibodies (ab-). Gene and phenotype frequencies of HLA-DQA1 alleles were similar in the ab+ and ab- subjects (P = NS). The data suggest that no single HLA-DQA1 allele is associated with the presence of serum antibodies against H. pylori.

HLA-G polymorphism in Finnish couples with recurrent spontaneous miscarriage.

HLA-G is a class I major histocompatibility complex gene that is expressed in cytotrophoblasts at the materno-fetal interface. It has been suggested that HLA-G could play a key role in materno-fetal immunological interactions during pregnancy. To investigate whether there is an association between HLA-G locus and recurrent spontaneous miscarriage, HLA-G alleles were determined by a PCR-RFLP method in 38 couples with recurrent spontaneous miscarriage and in 26 random control couples. In this series parental HLA-G sharing, extended HLA-G/A haplotypes and the frequencies of the HLA-G alleles were similar in the two groups. Thus, our data suggest that there is no detectable relation between susceptibility to recurrent spontaneous miscarriage and HLA-G locus.

Different distribution of T cell receptor beta-chain haplotypes in mixed connective tissue disease and systemic lupus erythematosus.

Mixed connective tissue disease (MCTD) and systemic lupus erythematosus (SLE) are autoimmune diseases with a genetic background, and it is reasonable to suggest that aberrations in T cell receptor (TCR) genes could contribute to these diseases, as they play an important role in immune regulation. We studied TCR beta-chain gene segments V beta 8, V beta 11 and C beta with restriction fragment length polymorphism (RFLP) in MCTD and SLE patients and controls. Haplotypes could be assigned in individuals who were homozygous for two or three of these three loci, whereupon the haplotype 2/25/10 (V beta 8/V beta 11/C beta) was found to be under-represented in MCTD (P = 0.029). The frequencies of individual alleles in both groups were similar to those of the controls, whereas the number of homozygotes within V beta 8 gene (23/23 kb and 2/2 kb) was increased in MCTD (P = 0.028). It is concluded that the distribution of TCR beta-chain genes could be aberrant in MCTD and could play a role in susceptibility, whereas the TCR beta-chain gene distribution in the SLE patients did not differ from that of the controls.

Plasmid associated antibody production against Yersinia enterocolitica in man.

The presence of plasmids was studied in 46 Yersinia enterocolitica strains isolated from human fecal specimens. In the 36 cases where specific antibodies were detected, 33 of the isolated bacteria were harbouring a 45-48 Mdalton plasmid responsible for autoagglutination and Ca2+ dependent growth at 37 degrees C. Symptoms compatible with yersiniosis were present in all patients where information was available. In the 10 cases with clinical symptoms but without specific antibodies only 2 of the isolated yersinia strains contained plasmids which were of another size. These results indicate an association between the presence of the 45-48 Mdalton plasmid in Y. enterocolitica strains and the pathogenicity of the strains to human hosts.