Assessment of IL-12, mRNA expression, vitamin-D level, and their correlation among the Mycobacterium tuberculosis cases

BACKGROUND: Tuberculosis (TB) presents serious health related complications caused by the Mycobacterium tuberculosis pathogen. Interleukin 12 (IL-12), plays a central role in T helper 1 (Th1) cells development that are implicated in chronic inflammatory pathogenesis as well as level of 1,25-dihydroxyvitamin D3 can impact on IL-12 mRNA expression at the transcriptional level. METHODS: The present study included clinically confirmed 100 Mycobacterium tuberculosis cases (TB) for assessment of IL-12 mRNA expression and vitamin-D level as well as equal number of healthy controls were also included. RESULTS: In TB cases, overall 13.01-fold higher IL-12 mRNA expression and 30.69 ng/ml vitamin-D level were observed. It was observed that higher expression of IL-12 mRNA expression was linked with TB cases had fever (p < 0.0001), night sweat (p = 0.003), sputum with blood (p = 0.03) as well as decreased vitamin-D level was linked with weight loss (p = 0.01), fever (p < 0.0001), night sweat (p = 0.008), sputum with blood (p = 0.005). TB cases with smoking (p < 0.0001) and alcoholism (p = 0.01, p = 0.0001) had significantly higher IL-12 mRNA expression and lower vitamin-D levels compared to its counterpart. It was observed that TB cases with vitamin-D deficiency, insufficiency, sufficiency had 19.51-fold, 14.64-fold, and 10.54-fold IL-12 mRNA expression respectively (deficiency vs insufficiency; p = 0.0003, deficiency vs sufficiency; p < 0.0001). A negative correlation was observed between IL-12 mRNA expression and vitamin-D level among the TB cases (r = -0.68, p < 0.0001). CONCLUSIONS: Higher IL-12 mRNA expression and lower vitamin-D expression among the TB cases may be responsible for the severity and pathogenesis of TB and alterations in IL-12 mRNA expression and vitamin-D may be influenced by the smoking and alcoholism habit of TB cases.