背景:在这项研究中,我们在通过近亲婚姻遗传IL-12R1基因的巴基斯坦患者中发现了多种突变.这些患者经历了严重的Bacille-Calmette-Guérin(BCG)感染以及复发性结核病。我们将证明白细胞介素(IL)-12/干扰素(IFN)-γ轴在分枝杆菌疾病的调节中的关键作用。
方法:首先,我们检查了病人的医疗记录,然后,我们通过ELISA评估干扰素-γ(IFN-γ)的产生。在此之后,提取DNA以研究IL-12/IFN-异常。通过Sanger测序进行全外显子组测序。从相同年龄组的健康对照比较分泌细胞因子水平,并且发现它们在疾病队列中显著更低。为了评估这些改变可能的功能影响,进行了一项计算机模拟研究。
结果:研究发现患者的PBMC产生的IFN-γ比预期的少得多。使用流式细胞术的分析显示活化的T细胞缺乏IL-12Rβ1的表面表达。IL-12Rβ1基因的外显子7,它编码细胞因子结合区(CBR)的一部分,和外显子10,编码纤连蛋白III型(FNIII)结构域,发现突变c.641A>G;p.Q214R和c.1094T>C;p.M365T,分别。计算机模拟分析表明,这些突变可能对蛋白质功能产生有害影响。
结论:我们的发现表明,IL-12/IFN-γ在抵抗分枝杆菌引起的感染方面具有重要作用。在近亲结婚的巴基斯坦患者中,在IL-12Rβ-1基因中鉴定出的突变提供了对严重BCG感染和复发性结核病的遗传基础的见解。该研究强调了在强制接种卡介苗的地区进行新生儿筛查的潜在效用。能够早期发现和干预与分枝杆菌感染相关的原发性免疫缺陷。此外,该研究表明,其他相关基因如IL-23Rβ1,TYK2或JAK2在IFN-γ产生中的潜在作用,保证进一步调查。
BACKGROUND: In this study, we have identified multiple mutations in the IL-12R1 gene among Pakistani patients who have inherited them through consanguineous marriages. These patients have experienced severe Bacille-Calmette-Guérin (BCG) infection as well as recurrent tuberculosis. We will demonstrate the pivotal role of interleukin (IL)-12/interferon (IFN)-γ axis in the regulation of mycobacterial diseases.
METHODS: First, we checked the patients\' medical records, and then afterward, we assessed interferon-gamma (IFN-γ) production through ELISA. Following that, DNA was extracted to investigate IL-12/IFN- abnormalities. Whole exome sequencing was conducted through Sanger sequencing. Secretory cytokine levels were compared from healthy control of the same age groups and they were found to be considerably less in the disease cohort. To evaluate the probable functional impact of these alterations, an in silico study was performed.
RESULTS: The study found that the patients\' PBMCs produced considerably less IFN-γ than expected. Analysis using flow cytometry showed that activated T cells lacked surface expression of IL-12Rβ1. Exon 7 of the IL-12Rβ1 gene, which encodes a portion of the cytokine binding region (CBR), and exon 10, which encodes the fibronectin-type III (FNIII) domain, were found to have the mutations c.641 A > G; p.Q214R and c.1094 T > C; p.M365T, respectively. In silico analysis showed that these mutations likely to have a deleterious effect on protein function.
CONCLUSIONS: Our findings indicate the significant contribution of the IL-12/IFN-γ is in combating infections due to mycobacterium. Among Pakistani patients born to consanguineous marriages, the identified mutations in the IL-12Rβ-1 gene provide insights into the genetic basis of severe BCG infections and recurrent tuberculosis. The study highlights the potential utility of newborn screening in regions with mandatory BCG vaccination, enabling early detection and intervention for primary immunodeficiencies associated with mycobacterial infections. Moreover, the study suggests at the potential role of other related genes such as IL-23Rβ1, TYK2, or JAK2 in IFN-γ production, warranting further investigation.