Differential B-cell responses are induced by Mycobacterium tuberculosis PE antigens Rv1169c, Rv0978c, and Rv1818c

Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
Clinical and Vaccine Immunology (Impact Factor: 2.37). 11/2007; 14(10):1334-41. DOI: 10.1128/CVI.00181-07
Source: PubMed

ABSTRACT The multigene PE and PPE family represents about 10% of the genome of Mycobacterium tuberculosis. Here, we report that three members of the PE family, namely, Rv1169c, Rv0978c, and Rv1818c, elicit a strong, but differential, B-cell humoral response among different clinical categories of tuberculosis patients. The study population (n = 211) was comprised of different clinical groups of both adult and child patients: group 1 (n = 94) patients with pulmonary infection, group 2 (n = 30) patients with relapsed infection, group 3 (n = 31) patients with extrapulmonary infections, and clinically healthy donors (n = 56). Among the PE proteins studied, group 1 adult patient sera reacted to Rv1818c and Rv0978c, while Rv1169c elicited immunoreactivity in group 3 children. However, all three PE antigens studied as well as the 19-kDa antigen did not demonstrate humoral reactivity with sera from group 2 patients with relapsed infection. The current study shows that while responsiveness to all three PE antigens is a good marker for M. tuberculosis infection, a strong response to Rv0978c or to Rv1818c by group 1 adult patients with pulmonary infection or largely restricted reactivity to Rv1169c antigen in child patients with extrapulmonary infections offers the possibility of differential utility in the serodiagnosis of tuberculosis.

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