title: Gm allotypes influence the production of IgG3 but the effect is age-dependent.
abstract: Serum concentrations of IgG3 were found to be higher in Gm-f-positive (= b-positive) than in f-negative individuals except in young children. Young children aged 3-4 months had a mean concentration of 0.24 g/l of IgG3 regardless of allotype. The concentration gradually rose with age in f-positive individuals to a geometric mean of 0.56 g/l in adults but it remained essentially unchanged in f-negative people. A corresponding allotype effect was seen in influenza-specific antibody responses. While the total IgG response (mainly IgG1) was equally strong in f-positive and in f-negative patients, f-positive (= b-positive) patients produced more IgG3 antibodies than f-negative patients. The difference between geometric mean values of opposite homozygotes (f/f versus f-negative) was 2.3-fold (p = 0.0113). This finding indicates that the b-positive gamma-3 allele is more productive than the g-positive allele.
authors.affiliation: Department of Bacteriology and Immunology, University of Helsinki, Finland.
authors.forename: N
authors.initials: N
authors.lastname: Rautonen
authors.forename: H
authors.initials: H
authors.lastname: Sarvas
authors.forename: I
authors.initials: I
authors.lastname: Julkunen
authors.forename: R
authors.initials: R
authors.lastname: Pyhälä
authors.forename: O
authors.initials: O
authors.lastname: Mäkelä
mesh_terms: D000328:Adult; D000367:Age Factors; D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral / Q000276:immunology; D002675:Child, Preschool; D006801:Humans; D007126:Immunoglobulin Allotypes / Q000276:immunology*; D007074:Immunoglobulin G / Q000096:biosynthesis*; D007223:Infant; D009980:Influenza A virus / Q000276:immunology; D007251:Influenza, Human / Q000276:immunology; D011863:Radioimmunoassay
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D007126:Immunoglobulin Allotypes; D007074:Immunoglobulin G