title: Neutralizing antibody to Pseudomonas aeruginosa exotoxin in human sera: evidence for in vivo toxin production during infection.
abstract: Antibody to Pseudomonas aeruginosa exotoxin was detected in human sera by using a cytotoxicity-neutralization assay. Serum antitoxin was present in high titer in all 14 patients who recovered from serious pseudomonas infections (log2 of 50% neutralization titer, mean +/- standard deviation = 6.0 +/- 1.2). In contrast, serum antitoxin was present in lower titer in four of seven patients with fatal pseudomonas infections (3.3 +/- 2.7, P less than 0.005), in 3 of 7 patients with non-pseudomonas infections (1.4 +/- 0.6 P less than 0.001), and in 6 of 14 normal control subjects (2.0 +/- 1.3, P less than 0.001). Fourfold or greater serum antitoxin rises were demonstrated in two survivors of acute infections, and toxin-neutralizing activity was associated with the immunoglobulin G fraction of human sera. Immunization of rabbits with purified exotoxin also induced high antitoxin titers.
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis*; D000992:Antitoxins / Q000032:analysis; D001427:Bacterial Toxins / Q000008:administration & dosage / Q000096:biosynthesis / Q000494:pharmacology*; D003601:Cytotoxicity Tests, Immunologic; D006801:Humans; D007114:Immunization; D008297:Male; D009500:Neutralization Tests; D011552:Pseudomonas Infections / Q000276:immunology*; D011550:Pseudomonas aeruginosa / Q000276:immunology*; D011817:Rabbits
chemical_list: D000907:Antibodies, Bacterial; D000992:Antitoxins; D001427:Bacterial Toxins