Author:
Appassakij H,Bunchuin N,Sarasombath S,Rungpitarangsi B,Manatsathit S,Komolpit P,Sukosol T
Abstract
A double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) was designed for the detection of Salmonella typhi protein antigen. The optimal concentration of antibody for coating the plate was found to be 50 micrograms/ml. The optimum conditions for antibody coating and antigen and conjugate incubation were 37 degrees C for 3 h, 37 degrees C for 2 h, and 4 degrees C overnight, respectively. The enzyme-substrate reaction was allowed to take place at 30 degrees C for 1 h. The established ELISA was found to be reproducible, with an inter-run coefficient of variation of less than 12% for the detection of an S. typhi protein antigen concentration of 0.5 to 50 micrograms/ml. The minimal detectable level of the antigen was 0.5 micrograms/ml. Cross-reactions were observed with the high level (50 micrograms/ml) of protein antigens obtained from Salmonella typhimurium, Escherichia coli, Salmonella paratyphi A, and Salmonella enteritidis. The ELISA established was used for the detection of S. typhi protein antigen in serum from 62 patients with typhoid, 30 patients with clinically diagnosed typhoid fever, 21 patients with paratyphoid, 17 patients with pyrexia caused by other bacteria, and 160 normal, healthy individuals. It was found that the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of this assay were 83.87, 89.04, 87.93, 67.53, and 95.31%, respectively.
Publisher
American Society for Microbiology
Reference22 articles.
1. ELISA for the measurement of intestinal antibody to Salmonella typhi protein antigen;Banchuin N.;Asian Pacific J. Allerg. Immunol.,1984
2. The serological specificities of Salmonella typhi antigens;Barber C.;Microbios,1976
3. Cross protection induced in mice by immunizations with proteins of related bacterial species. Zentralbl. Bakteriol. Parasitenkd;Barber C.;Infektionskr. Hyg. Abt. 1 Orig. Reihe A,1976
4. Contributions to the study of Salmonella immunological specificity of proteins separated from Salmonella typhi;Barber C.;Immunology,1966
5. Enzyme-linked immunosorbent assay for detection of Salmonella typhi VI antigen in urine from typhoid patients;Barrett T. J.;J. Clin. Microbiol.,1982
Cited by
21 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献