Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have investigated the human antibody repertoires that bind to two different classes of bacterial antigens. Immunization with the conventional antigen, type b capsular polysaccharide of Haemophilus influenzae Hib PS, uniformly induces IgA and IgG responses dominated by clones that use heavy chains structurally related to two subsets of VH3 genes, while in a minority of subjects antibodies from the VH1 or VH4 families are co-induced. In contrast, the "alternative binding site" of Staphylococcal Protein A (SPA) represents an unconventional determinant, because; (i) SPA is bound by a large proportion of non-immune IgM, IgA and IgG F(ab')2, (ii) SPA is bound only to Fab from the VH3 family, which can be encoded by at least four different germline genes, (iii) SPA binding is independent of VL usage, (iv) by flow cytometry SPA is bound by > 15% of tonsilar B cells, but not to T cells. (v) In vitro stimulation with an SPA containing mitogen induces the preferentially production of Ig bearing a VH3 marker. Taken together, these studies characterize a VH family restricted binding interaction that is distinct from the properties associated with conventional antigens such as Hib PS. Based on these data we propose that SPA represents a prototype for a B cell superantigen.
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PMID:Human antibody responses to bacterial antigens: studies of a model conventional antigen and a proposed model B cell superantigen. 148 69

Antibodies against capsular polysaccharides are important in the defense against many pathogenic bacteria. To determine the mechanism for the variability in responses to polysaccharides, a panel of well characterized serologic reagents that identify diagnostic primary amino acid sequences in the framework and hypervariable regions of heavy (H) and light (L) chains were created to characterize the variable region diversity in circulating human antibodies. 10 normal adult volunteers were immunized with the type b capsular polysaccharide of Haemophilus influenzae (Hib PS). By immunoblot analyses each individual was found to use at least three different variable L (VL) families, but all had preferential usage of VH3-derived H chains. Four individuals had lesser populations of VH1-derived H chains and three had populations of VH4-derived H chains, but anti-Hib PS antibodies derived from the VH2, VH5, and VH6 families were not detected. The anti-Hib PS antibodies from all subjects were also identified by serologic markers for two specific types of VH3 H chains. These H chains are structurally related to the 20P1 and 30P1 VH genes that are preferentially rearranged in the early human repertoire. These findings document the VH restriction of physiologic responses to Hib PS immunization, and demonstrate a technique to directly assess the structural and genetic diversity of specific serum antibodies.
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PMID:Variable region diversity in human circulating antibodies specific for the capsular polysaccharide of Haemophilus influenzae type b. Preferential usage of two types of VH3 heavy chains. 190 53