ABSTRACT: Low molecular mass protein-2 (LMP2) and low molecular mass protein-7 (LMP7) genes play a critical role in foreign antigen processing on the major histocompatibility complex-I CD8(+) cytotoxic T-lymphocyte pathway. This study was designed to investigate whether the sequence variants in the LMP2/LMP7 coding region were associated with intestinal Mycobacterium tuberculosis (M. tuberculosis) infection or with the co-infection of pulmonary tuberculosis.
A total of 168 patients with intestinal tuberculosis and 235 normal controls were recruited for this study. Two polymorphisms of LMP2 (Arg60-His) and LMP7 (Gln145-Lys) were identified by polymerase chain reaction-restriction fragment length polymorphism method. The associations of the LMP2/LMP7 genotype and haplotype with intestinal M. tuberculosis infection were assessed by using logistic regression analysis.
The results revealed that LMP7 position codon 145 Lys/Lys and Gln/Lys alleles in the coding region were associated with the infection of intestinal M. tuberculosis (P=0.003, odds ratio [OR]= 3.86 and P < 0.001, OR = 2.28, respectively). Meanwhile, the Arg-Lys and Cys-Lys haplotypes exhibited significant relation to the intestinal M. tuberculosis infection (P= 0.006, OR=1.87; P=0.021, OR=1.83, respectively). No significant associations were observed for any of the single-nucleotide polymorphism genotypes or haplotypes with the co-infection of pulmonary tuberculosis (P > 0.05).
The results indicated that the genetic variant within the LMP2/LMP7 gene would increase the risk of intestinal M. tuberculosis infection.
Journal of Gastroenterology and Hepatology 02/2011; 26(7):1145-50. · 2.87 Impact Factor
ABSTRACT: Despite the availability of effective vaccines, hepatitis B virus (HBV) infection is still commonly seen worldwide. Several reports show that the human major histocompatibility complex (MHC) systems were involved in the elimination of HBV via the restrictive antigen-processing pathway. We investigate whether LMP/TAP gene polymorphisms coded by MHC-II region were associated with HBV infection. A total of seven polymorphisms of LMP/TAP gene were identified by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) assays. Three hundred fifty-six patients and 326 unrelated healthy volunteers were included in the case-control study. Of the seven polymorphisms, three of which (LMP7 codons 145, TAP1 codons 637, and TAP2 codons 651) were observed to have statistically significant association with HBV infection (P < 0.05). We analyzed the three-locus haplotype constructed with three such polymorphisms and found that the frequency of haplotypes D and E increased significantly in patients, in comparison with that in controls (OR = 3.57, 95% CI: 2.09-6.12, P < 0.001; OR = 2.74, 95% CI: 1.35-5.56, P = 0.005, respectively). The results imply that LMP7-145, TAP1-637, and TAP2-651 sites were associated with the risk of HBV infection. Haplotypes D and E might be involved in the development of HBV infection. These data suggest a potential role of LMP/TAP gene as a candidate gene for susceptibility to HBV infection.
Journal of Clinical Immunology 09/2007; 27(5):534-41. · 3.08 Impact Factor
ABSTRACT: The T-box21 (TBX21) gene encodes the transcription factor T-bet (T-box expressed in T-cells), which influences naive T-lymphocyte development and has been implicated in the pathogenesis of many diseases.
We selected 208 hepatitis B patients and 213 healthy volunteers to examine whether polymorphisms or haplotypes of the TBX21 gene promoter were associated with hepatitis B virus (HBV) infection in the Chinese population. Two polymorphisms at -1499 and -1514 located in the TBX21 promoter region were identified by the PCR-restriction fragment length polymorphism (PCR-RFLP) method.
Single nucleotide polymorphism (SNP) at -1499 was significantly different between HBV patients and healthy controls [p=0.003; odds ratio (OR) 3.65, 95% confidence interval (CI) 1.58-8.45]. Similarly, our results showed a significantly higher level of haplotype D (--/AC) in HBV patients compared to control subjects (p=0.005; OR 4.82, 95% CI 1.59-14.61).
Based on our findings, it seems that genetic variations of allele -1499 and haplotype D (--/AC) within the TBX21 promoter region contribute to susceptibility to HBV infection in the Chinese population.
Clinical Chemistry and Laboratory Medicine 02/2007; 45(3):333-8. · 2.15 Impact Factor