title: Quantitative analysis of immunoglobulin G subclasses in the rat.
abstract: Quantitative ELISAs have been developed for the four immunoglobulin G (IgG) subclasses (IgG1, IgG2a, IgG2b and IgG2c) of the rat. These assays were shown to have excellent sensitivity, reproducibility and adequate specificity for studies of natural IgG and antigen-elicited IgG responses. The sensitivity (working range for each isotype assay) was: IgG1, 1.6 to 200 ng/ml; IgG2a, 8 to 200 ng/ml; IgG2b, 1.6 to 200 ng/ml; and IgG2c, 1.6 to 1000 ng/ml. The isotype sum and the direct assay of total plasma IgG agreed closely. The utility of these assays was demonstrated in a study of the development of total IgG and of the specific IgG response following immunization with tetanus toxoid (TT). For total IgG, the predominant isotype was IgG2b (64% of total IgG) followed by IgG2a (29%), IgG1 (4%) and IgG2c (3%). In contrast, the anti-TT response was mainly of the IgG1 subclass (57% of total anti-TT). These quantitative assays should prove useful for investigating the response to experimental vaccines and the influence of cytokines on class switching in vivo.
authors.affiliation: Department of Biochemistry, Medical College of Pennsylvania, Philadelphia 19129.
authors.forename: M
authors.initials: M
authors.lastname: Kinoshita
authors.forename: A C
authors.initials: AC
authors.lastname: Ross
mesh_terms: D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods* / Q000706:statistics & numerical data; D005069:Evaluation Studies as Topic; D007114:Immunization; D007074:Immunoglobulin G / Q000032:analysis* / Q000097:blood / Q000145:classification*; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D012680:Sensitivity and Specificity; D013745:Tetanus Toxoid / Q000276:immunology
chemical_list: D007074:Immunoglobulin G; D013745:Tetanus Toxoid