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Thorsten Thye Genevieve Scarisbrick Edmund N. L. Browne Margaret Amanua Chinbuah John Gyapong Ivy Osei Ellis Owusu-Dabo Stefan Niemann Sabine Rüsch-Gerdes Christian G. Meyer Rolf D. Horstmann 《PloS one》2009,4(7)
The gene of Cytotoxic T Lymphocyte-associated Antigen 4 (CTLA4), a negative regulator of T lymphocytes, contains a single-nucleotide polymorphism (SNP) at position +6230A->G (ct60A->G), which has been found associated with several autoimmune diseases and appears to reduce T-cell inhibitory activity. In Ghana, West Africa, we compared the frequencies of CTLA4 +6230 A/G and 6 haplotype-tagging SNPs in 2010 smear-positive, HIV-negative patients with pulmonary tuberculosis (TB) and 2346 controls matched for age, gender and ethnicity. We found no difference in allele frequencies between cases and controls. However, +6230A and a distinct CTLA4 haplotype and a diplotype comprising the +6230A allele were significantly less frequent among cases with large opacities in chest radiographs compared to those with small ones (Pcorrected [cor] = 0.002, Pcor = 0.00045, P = 0.0005, respectively). This finding suggests that an increased T-cell activity associated with the CTLA4 +6230G allele contributes to pathology rather than to protection in pulmonary TB. 相似文献
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Glucoraphasatin is an atypical glucosinolate mainly found in Raphanus sativus roots and sprouts. This review focuses on the chemistry, the occurrence, and the biological properties of glucoraphasatin. 相似文献
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Summary Conditioned culture medium from Daudi cells was used as a source of soluble H-Y antigen. Concentrated culture medium was labeled with 125I and then fractionated by gel filtration. Column fractions were assayed for the presence of H-Y antigen by urease-ELISA. H-Y antigen-containing fractions were then pooled and subjected to an improved immunoprecipitation protocol. Three predominant H-Y antigenic proteins were identified with estimated molecular weights of above 200,000, 50,000, and 20,000. 相似文献
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Abstract We have analyzed the sequence downstream of rpoN from Zcinetobacter calcoaceticus and identified an open reading frame encoding a protein with high similarity to UDP- N -acetylgucosamine 1-carboxyvinyl-transferase (MurZ). Multicopy plasmids encoding this enzyme conferred phosphomycin resistance to A. calcoaceticus . The polar effect of a rpoN mutation on the phosphomycin resistance level suggests that murZ is, in part, cotranscribed with rpoN . These observations confirm that A. calcoaceticus represents the first exceptin from a conserved genetic context of rpoN observed in several other Gram-negative bacteria. 相似文献
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In vivo neutralization of TNF-alpha promotes humoral autoimmunity by preventing the induction of CTL. 总被引:3,自引:0,他引:3
C S Via A Shustov V Rus T Lang P Nguyen F D Finkelman 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(12):6821-6826
Neutralization of TNF-alpha in humans with rheumatoid arthritis or Crohn's disease has been associated with the development of humoral autoimmunity. To determine the effect of TNF-alpha neutralization on cell-mediated and humoral-mediated responses, we administered anti-TNF-alpha mAb to mice undergoing acute graft-vs-host disease (GVHD) using the parent-into-F(1) model. In vivo neutralization of TNF-alpha blocked the lymphocytopenic features characteristic of acute GVHD and induced a lupus-like chronic GVHD phenotype (lymphoproliferation and autoantibody production). These effects resulted from complete inhibition of detectable antihost CTL activity and required the presence of anti-TNF-alpha mAb for the first 4 days after parental cell transfer, indicating that TNF-alpha plays a critical role in the induction of CTL. Moreover, an in vivo blockade of TNF-alpha preferentially inhibited the production of IFN-gamma and blocked IFN-gamma-dependent up-regulation of Fas; however, cytokines such as IL-10, IL-6, or IL-4 were not inhibited. These results suggest that a therapeutic TNF-alpha blockade may promote humoral autoimmunity by selectively inhibiting the induction of a CTL response that would normally suppress autoreactive B cells. 相似文献
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