Mass value assignment of total and subclass immunoglobulin G in a human standard anthrax reference serum.
An anti-Anthrax Vaccine Adsorbed (anti-AVA) standard human reference serum pool, AVR414, has been prepared, and the total and protective antigen (PA)-specific immunoglobulin G (IgG) were quantified. AVR414 was prepared by plasmapheresis of healthy adults who had received a minimum of four subcutaneous injections of AVA. Mass values (in milligrams per milliliter) for total IgG and IgG subclasses 1 to 4 were determined by radial immunodiffusion. Anti-PA-specific IgG assignment (in micrograms per milliliter) was done by consensus of two complementary approaches: homologous enzyme-linked immunosorbent assay (ELISA) with affinity-purified anti-PA IgG as a calibrator and summation of mean PA-specific IgG subclass concentrations determined by IgG subclass-specific ELISA using the United States National Reference Preparation for Human Serum Proteins as a standard. The total IgG concentration assigned to AVR414 reference serum was 8.33 mg/ml. IgG subclass concentrations were the following: for IgG1, 4.48 mg/ml; for IgG2, 3.35 mg/ml; for IgG3, 0.37 mg/ml; and for IgG4, 0.30 mg/ml. The assigned mass value for total anti-PA-specific IgG was 141.2 microg/ml. Anti-PA-specific IgG subclass concentrations were the following: for IgG1, 79.6 microg/ml; for IgG2, 35.3 microg/ml; for IgG3, 3.2 microg/ml; and for IgG4, 25.3 microg/ml. Human reference serum pool AVR414 will have direct application in the standardization of anthrax serological assays, in reagent qualification, and as a standard for quantification of PA-specific IgG in humans who have been vaccinated with or otherwise exposed to Bacillus anthracis PA.
Semenova
V A
VA
Meningitis and Special Pathogens Branch, Division of Bacterial and Mycotic Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA. vas7@cdc.gov
Steward-Clark
E
E
Stamey
K L
KL
Taylor
T H
TH
Schmidt
D S
DS
Martin
S K
SK
Marano
N
N
Quinn
C P
CP
D022122:Anthrax Vaccines / Q000276:immunology*; D000907:Antibodies, Bacterial / Q000097:blood; D000917:Antibody Formation; D000942:Antigens, Bacterial / Q000276:immunology; D001427:Bacterial Toxins / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards; D006801:Humans; D005779:Immunodiffusion / Q000592:standards; D007074:Immunoglobulin G / Q000097:blood* / Q000145:classification; D012015:Reference Standards
D022122:Anthrax Vaccines; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D007074:Immunoglobulin G; C030325:anthrax toxin