Detection of free and immune-complexed serine protease and its antibody in TB patients with and without HIV co-infection.

Abstract

OBJECTIVE:

To understand the usefulness of detecting tuberculous IgG antibodies against mycobacterial excretory-secretory 31 kDa serine protease antigen (SEVA TB ES-31) and circulating free and circulating immune-complexed (CIC) serine protease in TB patients with and without HIV infection.

DESIGN:

Serum was collected from 144 individuals: patients with TB, with TB-HIV co-infection and HIV infection only, and ill and healthy controls. SEVA TB ES-31 antigen, a serine protease isolated from Mycobacterium tuberculosis H37Ra culture fluid, was used in indirect penicillinase ELISA to detect tuberculous antibodies. Similarly, affinity purified anti-ES-31 antibody was used in sandwich ELISA to detect circulating free and CIC serine protease.

RESULTS:

There was less sensitivity for tuberculous antibody in HIV-infected TB patients (46%) than in those with TB alone (87%) using mycobacterial serine protease. However, the sensitivity of detection of TB in the presence of HIV increased to 87% by concomitant detection of circulating free and CIC serine protease antigen.

CONCLUSION:

Detection of free and CIC tuberculous serine protease antigen along with antibody is more useful for detecting TB in the presence of HIV co-infection.

• Authors: N Shende, S Gupta, A S Bhatia, S Kumar, B C Harinath
• Journal: The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease (Int J Tuberc Lung Dis) Vol. 9 Issue 8 Pg. 915-9 (Aug 2005) ISSN: 1027-3719 [Print] France
• PMID: 16104640 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigen-Antibody Complex
• Antigens, Bacterial
• Immunoglobulin G
• Serine Endopeptidases

Topics

• Antibody Formation
• Antigen-Antibody Complex (analysis)
• Antigens, Bacterial (immunology)
• Comorbidity
• Enzyme-Linked Immunosorbent Assay
• HIV Infections (complications, microbiology)
• Humans
• Immunoglobulin G (analysis)
• Serine Endopeptidases (immunology)
• Tuberculosis, Pulmonary (immunology, virology)