Department of Molecular & Human Genetics, Centre for Genomics, Jiwaji University, Gwalior, India.
Revised National Tuberculosis Control Programme Unit, District Hospital, Sheopur, India.
Indian J Med Res. 2017 Dec;146(6):768-773. doi: 10.4103/ijmr.IJMR_1582_15.
BACKGROUND & OBJECTIVES: Sahariya, a primitive tribe of Central India, has shown significantly increased incidence of pulmonary tuberculosis (PTB). Our previous study on Sahariya showed a significant association of -403G>A single nucleotide polymorphism (SNP) of CCL5 with susceptibility to PTB. Hence, this study was aimed to analyze a genotype-phenotype relationship of this disease-associated SNP to develop a potential diagnostic marker for TB in this tribe.
The present study was carried out on 70 plasma samples from Sahariya tribe, wherein the plasma CCL5 level was determined using a commercially available ELISA kit.
The level of CCL5 decreased significantly in patients who were on therapy/completed their therapy [inactive TB patient/inactive PTB (IPTB)], particularly with AA genotype of -403G>A (P=0.046). The level, with AA genotype, was also found to gradually decrease in sputum 3+ and 1+/2+ than in sputum-negative samples. Similarly, the CCL5 level was found to be higher in sputum-positive/active TB patients than in IPTB group and healthy controls.
INTERPRETATION & CONCLUSIONS: Our results suggested that the CCL5 level was influenced collectively not only by the genotypes of -403G>A SNP and bacillary load but also by the treatment. Thus, CCL5 may be considered for the development of a diagnostic marker and also as an indicator of recovery.
印度中部的原始部落撒哈里亚人肺结核（PTB）的发病率显著增加。我们之前对撒哈里亚人的研究表明，CCL5 的-403G>A 单核苷酸多态性（SNP）与 PTB 的易感性显著相关。因此，本研究旨在分析该疾病相关 SNP 的基因型-表型关系，以期为该部落开发潜在的 TB 诊断标志物。
本研究在 70 份来自撒哈里亚部落的血浆样本中进行，其中使用市售 ELISA 试剂盒测定血浆 CCL5 水平。
治疗中/已完成治疗的患者（活动性结核病患者/潜伏性肺结核患者，IPTB）的 CCL5 水平显著降低，尤其是-403G>A 的 AA 基因型（P=0.046）。还发现，与痰阴性样本相比，AA 基因型的 CCL5 水平在 3+和 1+/2+的痰液中逐渐降低。同样，与 IPTB 组和健康对照组相比，痰阳性/活动性结核病患者的 CCL5 水平更高。
我们的结果表明，CCL5 水平不仅受-403G>A SNP 基因型和细菌负荷的影响，还受治疗的影响。因此，CCL5 可被考虑用于开发诊断标志物，也可作为恢复的指标。
