ABSTRACT
The variability in the immune response modulated by HLA alleles may be an important factor for the induction of the protective effect of HBsAg vaccines. We present here the analysis of HLA-DRB1, DQB1 and DQA1 alleles and their combinations in the group of 36 individuals with poor humoral immmune response to HBsAg vaccination. Comparison with the control group, consisted of 60 randomly choosen healthy subjects, revealed that the DRB1*1601, DQB1*0502, DQA1*0102 haplotype is overrepresented in the group of hyporesponders and may therefore be regarded as a factor influencing poor antibody responsiveness. We observed that after revaccination two of three individuals who failed to develop anti-HBs antibodies carry the same phenotype DRB1*0101,DRB1*0301;DQB1*0501,DQB1*0201;DQA1+ ++*0101,DQA1*0501, which supports the conjecture that immunogenicity of the HBsAg vaccine depends on specific combination of HLA DR and DQ molecules on antigen presenting cells.
Subject(s)
Hepatitis B Surface Antigens/therapeutic use , Histocompatibility Antigens Class II/immunology , Vaccination , Alleles , Antibody Formation , Gene Frequency , HLA-DQ Antigens/genetics , HLA-DQ alpha-Chains , HLA-DQ beta-Chains , HLA-DR Antigens/genetics , HLA-DRB1 Chains , Haplotypes , Histocompatibility Antigens Class II/genetics , HumansABSTRACT
Fourier transform infrared spectra of fumaryl chloride 1 isolated in an argon matrix at 10 K have been analyzed. The comparison between the ab initio HF/6-31G calculated infrared spectra with the experimental ones reveals the existence of three planar conformers, the cis cis 1a, the cis trans 1b and the trans trans 1c. Laser UV irradiation of 1 at lambda = 340 nm yields maleoyl chloride 2 by a carbon carbon double bond photoisomerization process. The first identification of this compound was performed by comparison of the experimental infrared spectra with the calculated ones at the MP2/6-1G** level. AM1 semiempirical and ab initio calculations were used to calculate the structure and the relative stability of the three non planar maleoyl chloride conformers.
Subject(s)
Argon/chemistry , Fumarates/chemistry , Maleates/chemistry , Lasers , Molecular Conformation , Photolysis , Spectrophotometry, Infrared , Ultraviolet RaysABSTRACT
Studies both in spontaneously hypertensive rats and in humans have suggested that genes within or near to the HLA complex on chromosome 6p may be associated and linked to the regulation of blood pressure. The aim of this study was to determine whether HLA alleles and their combinations contribute to increased blood pressure, as well as to identify chromosome region that may contain genes involved in the pathogenesis of essential hypertension. Our results suggest that presence of HLA-DRB1*0101/2 DQB1*0501/2 DQA1*0102 allelic combination represents risk factor for development of essential hypertension in Slovenians, while the risk is decreased in individuals possessing HLA-DRB1*1601/2 DQB1*0502 DQA1*0102 or DRB3*. The linkage study indicates a possibility that at least one of the genes responsible for increased blood pressure is located near or within the HLA complex. A possible candidate is human endotelin-1 gene encoding a highly potent vasoactive peptide.
Subject(s)
Chromosome Mapping , Chromosomes, Human, Pair 6/genetics , Genetic Predisposition to Disease , Hypertension/genetics , Major Histocompatibility Complex/genetics , Adolescent , Gene Frequency , Genetic Linkage , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class II/genetics , Humans , Polymerase Chain ReactionABSTRACT
Studies both in spontaneously hypertensive rats and in humans have suggested that genes within or near to the HLA complex on chromosome 6p may be associated and linked to the regulation of blood pressure. The aim of this study was to determine whether HLA alleles and their combinations contribute to increased blood pressure, as well as to identify chromosome region that may contain genes involved in the pathogenesis of essential hypertension. Our results suggest that presence of HLA-DRB1*0101/2 DQB1*0501/2 DQA1*0102 allelic combination represents risk factor for development of essential hypertension in Slovenians, while the risk is decreased in individuals possessing HLA-DRB1*1601/2 DQB1*0502 DQA1*0102 or DRB3*. The linkage study indicates a possibility that at least one of the genes responsible for increased blood pressure is located near or within the HLA complex. A possible candidate is human endotelin-1 gene encoding a highly potent vasoactive peptide.