Surfactant Protein Genetic Marker Alleles Identify a Subgroup of Tuberculosis in a Mexican Population

Abstract

Pulmonary surfactant and its components are essential for normal lung function and are involved in local host defense. Surfactant protein (SP)—A and SP-D bind to and modulate phagocytosis of Mycobacterium tuberculosis by macrophages. Frequency comparisons of SP marker alleles in tuberculosis patients and healthy control subjects (tuberculin—skin test positive or general population) were performed. Regression analyses of the tuberculosis and the tuberculin—skin test positive groups revealed, on the basis of odds ratios, tuberculosis susceptibility (DA11_C and GATA_3) and protective (AAGG_2) marker alleles. Similarly, between tuberculosis patients and general population control subjects, susceptibility 1A³, 6A⁴, and B1013_A and protective AA GG_1, and AA GG_7 marker alleles were observed. Moreover, interactions were seen between alleles 6A² and 1A³ (P = .0064) and between 1A³ and B1013_A (P = .036). The findings indicate a possible involvement of SP alleles in tuberculosis pathogenesis.