Evaluation of integral membrane antigens of Mycobacterium habana for serodiagnosis of extrapulmonary tuberculosis: association between levels of antibodies and Mycobacterium tuberculosis antigens

Abstract

The performance of integral membrane antigens (IMAs) of Mycobacterium habana TMC 5135 in detecting antimycobacterial antibodies in serum and body fluids of patients mainly of extrapulmonary tuberculosis was evaluated. The IMAs were recovered from the detergent phase during Triton X-114 treatment of the plasma membrane of M. habana. Antimycobacterial antibodies were detected by ELISA using IMAs in serum and body fluids of 42 patients and 62 control subjects. As authentic adjunct Mycobacterium tuberculosis antigens were also detected (by ELISA) in body fluids and circulating immune complexes using anti-M. tuberculosis H37Ra antibodies. Anti-M. habana IMA antibody detection increased the positivity rate from 26.% (11/42) and 10% (4/42) obtained by culture and smear microscopy, respectively, to 86% (36/42). M. tuberculosis antigens were also found in 29 out of 36 anti-M. habana IMA antibody-positive cases. Interestingly, all 11 culture-positive cases were also positive for anti-M. habana IMA antibodies. The mean antigen titres in 23 cases, positive for antigens in body fluids, were 2.34 times higher in those who were also positive for anti-IMA antibodies in serum than in those negative for these antibodies. M. habana IMAs may be promising non-tubercular candidate antigens in ELISA-based serodiagnosis of extrapulmonary tuberculosis with substantial sensitivity, specificity and safety.

Assessment of antigenic fractions of varying hydrophobicity from Taenia solium metacestodes for the diagnosis of human neurocysticercosis

“…The major advantages of using antigens purified by TX‐114 solution are minimal cost for production in the laboratory, simple and easy extraction, high efficiency, speed and lower toxicity to the environment than extractions involving organic solvents (Manzoori & Bavili‐Tabrizi 2002). Good results have been obtained using fraction D, as described by Chaturvedi and Gupta (2002), where the performance of integral membrane antigens of Mycobacterium habana recovered from the fraction D during TX‐114 treatment showed promising non‐tubercular candidate antigens in ELISA‐based serodiagnosis of extrapulmonary tuberculosis with substantial sensitivity, specificity and safety.…”

Diagnosis of Mycobacterium tuberculosis

“…Tests using such antigens were designed to detect immunoglobulins IgG, IgM, or IgA against these TB-specific antigens in whole blood, plasma, or serum of both pulmonary and extra-pulmonary TB patients (Imaz et al, 2001;Raja et al, 2002Raja et al, , 2004Ramalingam et al, 2002;Zheng et al, 1994;Patil et al, 1996). Antigens from mycobacteria other than Mtb (M. habana) were also evaluated for their ability to diagnose extra-pulmonary TB using ELISA, and these antigens were found to be effective (Chaturvedi & Gupta 2001). To date, the 38-kDa antigen is the best candidate for the ELISA technique for diagnosing TB in actively infected individuals-but it is not reliable in extra-pulmonary or TB-HIV co-infected patients (Abebe et al, 2007).…”