Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, Lyon, France.
Département des Maladies infectieuses et tropicales, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France.
Front Immunol. 2022 Jul 27;13:919806. doi: 10.3389/fimmu.2022.919806. eCollection 2022.
Herpes zoster, which is due to the reactivation of Varicella zoster virus (VZV), is a leading cause of morbidity after allogeneic hematopoietic stem cell transplantation (allo-HSCT). While cell-mediated immunity (CMI) is critical to inhibiting VZV reactivation, CMI is not routinely assessed due to a lack of reliable tests. In this study, we aimed to evaluate VZV-specific CMI among allo-HSCT recipients (n = 60) and healthy individuals (HI, n = 17) through a panel of three immune functional assays after stimulation by VZV antigen: quantification of (i) IFN-γ release in the supernatants, (ii) T-cell proliferation after a 7-day stimulation of peripheral blood mononuclear cells (PBMC), and (iii) measurement of the - mRNA gene expression level after 24 h of stimulation of a whole-blood sample. VZV responsiveness was defined according to IFN-γ release from VZV-stimulated PBMC. Upon VZV stimulation, we found that allo-HSCT recipients at a median time of 6 [5-8] months post-transplant had lower IFN-γ release (median [IQR], 0.34 [0.12-8.56] vs. 409.5 [143.9-910.2] pg/ml, <.0001) and fewer proliferating T cells (0.05 [0.01-0.57] % vs. 8.74 [3.12-15.05] %, <.0001) than HI. A subset of allo-HSCT recipients (VZV-responders, n = 15/57, 26%) distinguished themselves from VZV-non-responders (n = 42/57, 74%; missing data, n = 3) by higher IFN-γ release (80.45 [54.3-312.8] vs. 0.22 [0.12-0.42] pg/ml, <.0001) and T-cell proliferation (2.22 [1.18-7.56] % vs. 0.002 [0.001-0.11] %, <.0001), suggesting recovery of VZV-specific CMI. Interestingly, VZV responders had a significant fold increase in gene expression, whereas mRNA was not detected in whole blood of VZV-non-responders ( <.0001). This study is the first to suggest that measurement of gene expression in 24-h-stimulated whole blood could be an accurate test of VZV-specific CMI. The routine use of this immune functional assay to guide antiviral prophylaxis at an individual level remains to be evaluated.
带状疱疹是由水痘-带状疱疹病毒（Varicella zoster virus，VZV）再激活引起的，是异基因造血干细胞移植（allogeneic hematopoietic stem cell transplantation，allo-HSCT）后发病的主要原因。细胞介导的免疫（cell-mediated immunity，CMI）对于抑制 VZV 再激活至关重要，但由于缺乏可靠的检测方法，CMI 通常无法进行评估。本研究旨在通过 VZV 抗原刺激后的三种免疫功能检测（外周血单个核细胞 [peripheral blood mononuclear cells，PBMC] 刺激后 7 天的 T 细胞增殖，以及全血样本刺激 24 小时后的 -mRNA 基因表达水平测量）评估 allo-HSCT 受者（n=60）和健康个体（healthy individuals，HI，n=17）的 VZV 特异性 CMI。根据 VZV 刺激 PBMC 产生的 IFN-γ 释放情况，将 VZV 反应性定义为阳性。在 VZV 刺激后，我们发现中位时间为移植后 6 [5-8] 个月的 allo-HSCT 受者 IFN-γ 释放水平较低（中位数[四分位距]，0.34 [0.12-8.56] vs. 409.5 [143.9-910.2] pg/ml， <.0001），增殖的 T 细胞较少（0.05 [0.01-0.57]% vs. 8.74 [3.12-15.05]%， <.0001），低于 HI。一组 allo-HSCT 受者（VZV 反应者，n=15/57，26%）与 VZV 非反应者（n=42/57，74%；缺失数据，n=3）通过更高的 IFN-γ 释放（80.45 [54.3-312.8] vs. 0.22 [0.12-0.42] pg/ml， <.0001）和 T 细胞增殖（2.22 [1.18-7.56]% vs. 0.002 [0.001-0.11]%， <.0001）进行区分，表明 VZV 特异性 CMI 恢复。有趣的是，VZV 反应者的 基因表达有显著的倍数增加，而 VZV 非反应者的全血中未检测到 mRNA（<.0001）。本研究首次表明，24 小时刺激全血中 基因表达的测量可能是 VZV 特异性 CMI 的准确检测方法。该免疫功能检测的常规使用，以指导个体水平的抗病毒预防，尚待评估。
