Enzyme immunoassay detection of antigen-specific immunoglobulin g antibodies in longitudinal serum samples from patients with cryptosporidiosis.

Abstract

Cryptosporidium parvum is a protozoan parasite that causes diarrheal illness in a wide range of mammalian hosts, including humans. Characteristic serum immunoglobulin G (IgG) antibody responses to antigens in the 27- and 17-kDa size ranges have been shown to develop after infection, and several enzyme-linked immunosorbent assay (ELISA) and Western blot assay formats have been used to measure these IgG levels in human serum. Using a collection of serial samples from laboratory-confirmed cryptosporidiosis patients, we compared the results obtained by using two new ELISAs with those obtained with two different Western blot assays. When assayed with the large-format Western blot, 97% of the 67 patients had a demonstrable antibody response on at least one occasion. The Cp23 ELISA correctly identified 93% of the samples that had a 27-kDa response by Western blot and 100% of the negative samples. The Triton antigen ELISA detected 77% of the samples that had a 17-kDa response by Western blot and 88% of the negative samples. The sensitivity of the Triton antigen assay was higher for samples collected between 16 and 92 days after the onset of symptoms (96%). The minigel-format Western blot did not compare favorably with the large-format blot for the detection of antibodies to the 27-kDa antigen (71% sensitivity). A half-life of about 12 weeks was estimated for antibodies to both the 27- and 17-kDa antigens. We believe the Cp23 and Triton antigen ELISAs will be useful in epidemiologic studies of the prevalence of Cryptosporidium infection in the population.

• Authors: J W Priest, A Li, M Khan, M J Arrowood, P J Lammie, C S Ong, J M Roberts, J Isaac-Renton
• Journal: Clinical and diagnostic laboratory immunology (Clin Diagn Lab Immunol) Vol. 8 Issue 2 Pg. 415-23 (Mar 2001) ISSN: 1071-412X [Print] United States
• PMID: 11238231 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigens, Protozoan
• Immunoglobulin G

Topics

• Adult
• Animals
• Antigens, Protozoan (analysis, immunology)
• Blotting, Western
• Cryptosporidiosis (diagnosis, epidemiology)
• Cryptosporidium parvum (immunology, isolation & purification)
• Enzyme-Linked Immunosorbent Assay (methods)
• Humans
• Immunoglobulin G (blood)
• Longitudinal Studies
• Sensitivity and Specificity
• Seroepidemiologic Studies