School of Pathology and Laboratory Medicine, University of Western Australia, Perth, Australia.
AIDS. 2011 Jul 31;25(12):1455-60. doi: 10.1097/QAD.0b013e328348fb18.
Most HIV patients who experience Mycobacterium tuberculosis-associated immune restoration disease (TB IRD) display elevated interferon-gamma (IFNγ) responses against mycobacterial antigens, but these can occur without an IRD. Recognition of mycobacteria-associated molecular patterns through toll-like receptors (TLRs) on dendritic cells and monocytes induces cytokine production. Here, we investigate TLR-induced responses in IRD.
Peripheral blood mononuclear cells (PBMCs) were collected at approximately weeks 0, 6, 12, 24 and 48 after antiretroviral therapy from five patients experiencing TB IRD, nine matched non-IRD patients and 15 healthy controls.
IFNγ production by PBMC stimulated with protein purified derivative (PPD) was assessed by ELISpot. TLR2 expression on myeloid dendritic cells (mDCs) and monocytes was assessed by flow cytometry. TNFα, IL-12p40 and IL-10 were measured by ELISA in 24-h cultures of PBMC with lipomannan (mycobacteria-derived TLR2 agonist).
TLR2 expression on mDC and monocytes was higher in patients than controls at baseline (P < 0.005). TLR2 expression decreased to normal levels on mDC by week 12, but remained higher on monocytes at week 24 (P = 0.02). At week 24, IRD patients showed higher IFNγ responses to PPD (P = 0.02), TLR2 expression on monocytes (P = 0.006) and lipomannan-induced TNFα production (P = 0.016) than non-IRD patients. Lipomannan-induced TNFα and IL-12p40 responses paralleled TB IRD in the patients with high TLR2 expression. IL-10 levels did not associate with IRD.
TLR2-induced pro-inflammatory cytokines by dendritic cells or monocytes may contribute to the pathogenesis of mycobacterial IRD.
大多数经历结核分枝杆菌相关免疫重建疾病（TB IRD）的 HIV 患者对分枝杆菌抗原表现出升高的干扰素-γ（IFNγ）反应，但这些反应也可能在没有 IRD 的情况下发生。树突状细胞和单核细胞上的 toll 样受体（TLR）识别分枝杆菌相关的分子模式，诱导细胞因子的产生。在这里，我们研究了 IRD 中的 TLR 诱导反应。
在抗逆转录病毒治疗后大约 0、6、12、24 和 48 周，从 5 名经历 TB IRD 的患者、9 名匹配的非 IRD 患者和 15 名健康对照中收集外周血单核细胞（PBMC）。
通过酶联免疫斑点法（ELISpot）评估 PBMC 用蛋白纯化衍生物（PPD）刺激后的 IFNγ 产生情况。通过流式细胞术评估髓样树突状细胞（mDC）和单核细胞上的 TLR2 表达。用脂甘露聚糖（分枝杆菌衍生的 TLR2 激动剂）对 PBMC 进行 24 小时培养，用 ELISA 测定 TNFα、IL-12p40 和 IL-10。
与对照组相比，患者的 mDC 和单核细胞上的 TLR2 表达在基线时更高（P < 0.005）。TLR2 表达在第 12 周时降至正常水平，但在第 24 周时仍在单核细胞上升高（P = 0.02）。在第 24 周，IRD 患者对 PPD 的 IFNγ 反应（P = 0.02）、单核细胞上的 TLR2 表达（P = 0.006）和脂甘露聚糖诱导的 TNFα 产生（P = 0.016）均高于非 IRD 患者。具有高 TLR2 表达的患者中，脂甘露聚糖诱导的 TNFα 和 IL-12p40 反应与 TB IRD 平行。IL-10 水平与 IRD 无关。
树突状细胞或单核细胞中 TLR2 诱导的促炎细胞因子可能有助于分枝杆菌 IRD 的发病机制。
