title: Distribution of IgG subclass levels in normal adult sera as determined by a competitive enzyme immunoassay using monoclonal antibodies.
abstract: IgG subclass levels were measured by an indirect competitive immunoenzymatic assay with selected monoclonal antibodies in sera from 180 adult blood donors. Mean levels were 6.35 mg/ml (65% of the sum of the subclasses) for IgG1, 2.61 mg/ml (26.2%) for IgG2, and 0.414 mg/ml (4.3%) for IgG3. IgG4 levels were significantly different in men (mean 0.456 mg/ml, 4.8% of the sum) and women (mean 0.29 mg/ml, 3.2%), with very wide ranges. The distribution of IgG2 levels was more homogeneous than that of IgG4 but more heterogeneous than those of IgG1 and IgG3, with a number of sera that displayed low levels of IgG2.
mesh_terms: D000293:Adolescent; D000328:Adult; D000911:Antibodies, Monoclonal; D001667:Binding, Competitive; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis / Q000145:classification*; D008297:Male; D008875:Middle Aged; D009391:Nephelometry and Turbidimetry; D013223:Statistics as Topic
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G