Serum bactericidal activity against Neisseria meningitidis in patients with C3 nephritic factors is dependent on IgG allotypes.

• The main mechanisms of immune defense against Neisseria meningitidis are serum bactericidal activity (SBA) and opsonophagocytosis. Many complement deficiencies, among them acquired partial C3 deficiency due to stabilizing autoantibodies against the alternative pathway C3 convertase (C3 nephritic factors, C3 NeF); increase the risk of meningococcal infection. SBA against meningococci in patients with C3 NeF was determined along with allelic variants (GM alleles) of the immunoglobulin constant heavy G chain (IGHG) genes. In patients with C3 NeF and in control children, individuals homozygous for G1Mf and G3Mb showed higher SBA against meningococci than heterozygous individuals. Partial complement deficiency in early childhood might explain the influence of GM variants on SBA in control children. These novel findings imply that the IGHG genotype is important in defense against meningococci in individuals with low complement function and possibly in combination with other immunodeficiencies.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Immunologi inom det medicinska området (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Immunology in the medical area (hsv//eng)

Publication and Content Type

art (subject category)

ref (subject category)