Fiorenza Gladys, Farroni Miguel A, Bogué Cristina, Selenscig Dante, Lamas Diego Martinel, Dlugovitzky Diana
Sección Inmunología, Cátedra de Microbiología. Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina.
Arch Med Res. 2007 Jul;38(5):526-33. doi: 10.1016/j.arcmed.2007.01.011. Epub 2007 Apr 26.
The major protective immune response against intracellular bacteria, such as Mycobacterium tuberculosis, is a cell-mediated immunity involving neutrophils (PMNs) and peripheral mononuclear cells (MCs), contributing to the clearance of this microorganism and the resolution of the infection. This study was addressed to evaluate PMNs and MCs for their bactericidal function.
The sample comprised 14 tuberculosis (TB) inpatients (HIV-), and 10 healthy controls (HCo). Peripheral PMNs and MCs were separated by Ficoll-Hypaque and cultured in RPMI with or without heat-killed Mycobacterium tuberculosis (HK Mtb). Respiratory burst (RB), CD11b, IL-8 and TNFalpha receptor expression were assessed by flow cytometry in cells undergoing stimulation or not. Presence of IL-8 and TNFalpha in cell culture supernatants was determined by ELISA.
TB patients had a lower RB response than HCo for both cell types (MCs, p <0.05, PMNs, p <0.01) regardless of HK Mtb stimulation. Compared to HCo, PMNs and MCs from TB patients presented a reduced CD11b expression, with the two subject groups showing a decrease in this marker expression following HK. Mtb was added to both cell cultures. Whereas fewer IL-8 and TNFalpha receptors were found when studying MCs and PMNs from TB patients, antigen stimulation significantly raised the expression for both cytokine receptors. Culture supernatants from MCs and PMNs of TB patients contained increased amounts of IL-8 and TNFalpha.
The present findings may provide some explanation as to the different roles played by PMNs and MCs in TB immunopathology.
针对细胞内细菌（如结核分枝杆菌）的主要保护性免疫反应是一种细胞介导的免疫，涉及中性粒细胞（PMN）和外周单核细胞（MC），有助于清除这种微生物并解决感染问题。本研究旨在评估PMN和MC的杀菌功能。
样本包括14名结核病（TB）住院患者（未感染HIV）和10名健康对照者（HCo）。通过Ficoll-Hypaque分离外周PMN和MC，并在含有或不含有热灭活结核分枝杆菌（HK Mtb）的RPMI中培养。通过流式细胞术评估受刺激或未受刺激细胞中的呼吸爆发（RB）、CD11b、IL-8和TNFα受体表达。通过ELISA测定细胞培养上清液中IL-8和TNFα的存在情况。
无论是否有HK Mtb刺激，TB患者的两种细胞类型（MC，p<0.05；PMN，p<0.01）的RB反应均低于HCo。与HCo相比，TB患者的PMN和MC的CD11b表达降低，两个受试者组在添加HK Mtb后该标志物表达均下降。在研究TB患者的MC和PMN时发现较少的IL-8和TNFα受体，但抗原刺激显著提高了两种细胞因子受体的表达。TB患者的MC和PMN的培养上清液中IL-8和TNFα的含量增加。
本研究结果可能为PMN和MC在结核病免疫病理学中所起的不同作用提供一些解释。
