Evaluation of human antibody responses to diphtheria toxin subunits A and B in various age groups.
This study aimed to evaluate human antibody responses to diphtheria toxin subunits in various age groups. Antibodies against the intact diphtheria toxin and the diphtheria toxin subunits A and B were evaluated in 1319 individuals using a double-antigen ELISA. Although high levels of protection (83.6%, 95% CI 79.2-87.4) were found in children and adolescents, the middle-aged adult population was less protected (28.8%, 95% CI 24.3-33.6). An increase in age was associated with a decrease in the frequency of protected individuals in the 0-39-year age group (p <0.001). Anti-subunit B levels correlated well (p <0.01) with levels of antibodies against the intact toxin. In children aged < or =16 years, the intervals at which the peaks in geometric mean titres of anti-subunit B antibodies were observed were found to correlate with the ages at which booster doses are administered. Overall, males appeared to be more protected than females (OR 1.67, 95% CI 1.34-2.08, p <0.001). A small group of individuals had antibody levels of > or =0.1 IU/mL against the intact toxin, but did not have protective antibody against subunit B. Determination of anti-subunit B antibody levels should help in evaluating the effectiveness of diphtheria boosters and other aspects of diphtheria immunity.
Karakus
R
R
Department of Immunology, Gazi University, Faculty of Medicine, Ankara, Turkey. rkarakus@gazi.edu.tr
Caglar
K
K
Aybay
C
C
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000907:Antibodies, Bacterial / Q000096:biosynthesis* / Q000276:immunology; D000917:Antibody Formation / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D004165:Diphtheria / Q000382:microbiology / Q000517:prevention & control*; D004167:Diphtheria Toxin / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000276:immunology*
D000907:Antibodies, Bacterial; D004167:Diphtheria Toxin; D010446:Peptide Fragments; C029795:diphtheria toxin fragment A; C039171:diphtheria toxin fragment B