Role played by human mannose-binding lectin polymorphisms in pulmonary tuberculosis

Abstract

Background. Mannose-binding lectin (MBL) activates the complement system in an antibody-independent manner, enhances complement-mediated phagocytosis, and plays a major role in the regulation of inflammatory cytokine release by monocytes. Methods. Case patients (277 patients with pulmonary tuberculosis) and control subjects (288 household contacts) were tested by polymerase chain reaction (PCR) for polymorphisms at the promoter and the exon 1 regions of the MBL gene. Diagnosis of pulmonary tuberculosis, based on findings from chest radiography and sputum smear examination, was confirmed by PCR and bacteriological tests. Results. HYA/HYA subjects were protected against tuberculosis (odds ratio [OR], 0.09 [95% confidence interval {CI}], 0.023-0.408; P < 1 × 10-8). LYB/LYD subjects were susceptible to disease (OR, 49 [95% CI, 2.9-812.5]; P < 1 × 10-6). Conclusions. This study supports the conclusion that MBL can protect or predispose the host to tuberculosis, depending on the host's haplotype pair. © 2009 by the Infectious Diseases Society of America. All rights reserved.