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)

Haemophilus influenzae type b capsular polysaccharide (PRP) conjugate vaccines, which are thought to induce T cell-dependent antibody production, induce protective responses after a single dose in individuals under 15 months of age. However, multiple doses of these vaccines are required to induce protective antibody responses in infants, with the exception of PRP conjugated to meningococcal outer membrane proteins (OMPC), which does so after a single dose. The basis for this difference is not fully understood, although others have proposed that OMPC and porins, the major protein component of OMPC, act as adjuvants or mitogens. In this report OMPC is shown to enhance CD40 ligand-mediated, T cell-dependent antibody production in mice. This paralleled the induction by OMPC of CD86, CD80 and CD40 costimulatory molecules on human neonatal and murine B cells and of Th1 cytokines. Neither porins nor lipopolysaccharide fully reproduced the effects of OMPC. These studies indicate that OMPC acts both as carrier and adjuvant, and thereby enhances T cell-dependent antibody responses in human infants.
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PMID:Carrier-mediated enhancement of cognate T cell help: the basis for enhanced immunogenicity of meningococcal outer membrane protein polysaccharide conjugate vaccine. 1150 Aug 20

Nontypeable Haemophilus influenzae (NTHi) colonizes the upper respiratory tract of most healthy people and is also a major cause of infection in chronic obstructive lung disease. The immune response to this bacterium has not been well characterized. We tested the hypothesis that recurrent airway infection with NTHi may be associated with nonclearing adaptive immunity. Study subjects were healthy control subjects and patients with idiopathic bronchiectasis who had severe chronic infection with H. influenzae. We established that all subjects in both groups had detectable antibody to NTHi, suggesting that most normal people have developed an adaptive immune response. To characterize the nature of the immune response, we measured antigen-specific production of T helper cell cytokines and CD40 ligand by flow cytometry and immunoglobulin subclass levels in peripheral blood. We found that normal control subjects made Th1 response to NTHi with distinct CD40 ligand production. In contrast, subjects with bronchiectasis had predominant production of Th2 cytokines, decreased expression of CD40 ligand, and different immunoglobulin G subclass production. Therefore, chronic infection with NTHi in bronchiectasis is associated with a change in adaptive immunity that may be important in the pathogenesis of bronchial infection.
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PMID:Adaptive immunity to nontypeable Haemophilus influenzae. 1258 10