2 vs. 2.5%; OD=7.53) and DR1 (51.4 vs. 10.0%; OD=9.53) alleles were significantly increased in the patients as compared with the controls, while B5 (6.7 vs. 25.0%), DR8 (1.9 vs. 17.5%), and DQ3 (11.4 vs. 45.0%) alleles were significantly decreased. However, a significant corrected level was maintained for only DR1, DR8, and DQ3 alleles (Pc=1.9×10 -5 , 0.02 and 1.0×10 -4 , respectively). Table 1 Observed numbers and percentage frequencies of human leukocyte antigen (HLA)-class I (A and B) alleles in the pulmonary buy NLG919 tuberculosis patients Inhibitors,research,lifescience,medical and controls Table 2 Observed numbers and percentage frequencies of human leukocyte antigen (HLA)-class II (DR and DQ) alleles in the pulmonary tuberculosis patients and controls

Table 3 HLA alleles show a significant variation between the pulmonary tuberculosis patients and controls Discussion Several studies have been Inhibitors,research,lifescience,medical carried out to understand whether the susceptibility and/or immune response to M. tuberculosis is associated with HLA phenotype and/or controlled by the genes that are linked to MHC.8,9,12 Studies have also been conducted to find relevant T- cell epitopes of M. tuberculosis antigens and

their peptides in the context Inhibitors,research,lifescience,medical of HLA-DR molecules and to define their usefulness for diagnosis or vaccine design.13 For HLA-class I alleles, none of the inspected alleles maintained a significant corrected variation between the patients and controls, although B8 was increased and B5 was decreased in the patients. However, other investigators have reported different positive and negative associations. Hans et al.14 considered A11 and B15 alleles as risk factors for tuberculosis in Americans. On the other hand, Lewinsohn et Inhibitors,research,lifescience,medical al.15stated that HLA-B alleles were served as the dominant MHC class I restricting molecules for anti-mycobacterium-specific CD8+ T cell responses

measured in CD8+ T cells from patients with PT. These results were in agreement with the previous studies that approved the association between certain HLA types and infectivity and tuberculosis.16 Nevertheless, Vijaya et al.17 suggested Inhibitors,research,lifescience,medical that B52 (split of B5) had a negative association (protective effect) with PT, a suggestion that chimes in with the findings of the present study. medroxyprogesterone The present study also revealed that DR1 was significantly higher in the PT patients than the controls; an observation that may suggest that this allele is a PT predisposing factor in Iraqis, especially when we consider an OR of 9.53 and EF value of 0.46. In contrast, DR8 and DQ3 might be associated with a protective effect. In this regard, it has been demonstrated that an altered memory response to M. tuberculosis in DR1 negative patients was observed in favor of curing.18 The same authors reported that DR8 was associated with resistance to PT, as was the case in the present study. However, further inconsistent observations have also been documented.