Antibody-dependent alternative pathway killing of Haemophilus influenzae type b.

摘要: Abstract The bactericidal activities of human complement and antibody directed against specific Haemophilus influenzae type b cell surface determinants were investigated. Strain Eagan, a laboratory isolate, strain Kn, clinical used as the test organisms gave qualitatively similar results. In absence antibody, both isolates resistant to killing by 60% agammaglobulinemic serum (AGS) containing normal levels. The addition affinity-purified immunoglobulin G anticapsular was with 15% AGS source. Bactericidal activity also demonstrated this when source AGS-Mg-EGTA [ethylene glycol-bis(beta-aminoethyl ether)-N,N-tetraacetic acid], C2-deficient (alternative pathway), or in which factor D properdin had been selectively inactivated (classical pathway). Immunoglobulin fractions from pool an adult who recovered H. (Kn) sepsis absorbed remove antibody. noncapsular antibodies activated complement-dependent activity. But, contrast results did not elicit alternative pathway Incubation cells cause consumption (total hemolytic C3). (but antibody) increased total C3, paralleling assays. These studies absolute requirement for activation b.(ABSTRACT TRUNCATED AT 250 WORDS)