Association between interleukin-27 polymorphisms and pulmonary tuberculosis

OBJECTIVE: To investigate the effect of interleukin (IL) 27 −964A/G, 2095T/G, 4603G/A and 4730T/C gene polymorphisms on the development of pulmonary tuberculosis (PTB), radiographic characteristics and severity.

DESIGN: Differences in the allele and genotype distributions of the −964A/G, 2095T/G, 4603G/A and 4730T/C polymorphisms between 224 PTB patients and 233 healthy controls, between patients with single- and multi-lobe involvement, and between patients with and without cavitation, were investigated. Serum IL-27 concentration was measured using an enzyme-linked immunosorbent assay.

RESULTS: There were no significant differences in the allele or genotype distributions between PTB patients and healthy controls. However, the −964A/A genotype was more prevalent in patients with single-lobe involvement than the −964A/G or −964G/G genotype in patients with multi-lobe involvement (50.0% vs. 31.3%, P = 0.01). There was no difference between patients with and without cavitation (P > 0.05). Serum median IL-27 concentration was significantly higher in patients with single-lobe involvement than in those with multi-lobe involvement (P = 0.03) and in those with −964A/A genotypes than in those with −964A/G or −964G/G genotypes (P = 0.02).

CONCLUSIONS: In terms of serum IL-27 levels, the −964 A/A genotype may be associated with a protective role that prevents the intrapulmonary spread of PTB rather than its development.