DataSheet_1_Longitudinal Analysis of Dengue Virus–Specific Memory T Cell Responses and Their Association With Clinical Outcome in Subsequent DENV Infection.pdf

Memory T cells resulting from primary dengue virus (DENV) infection are hypothesized to influence the clinical outcome of subsequent DENV infection. However, the few studies involving prospectively collected blood samples have found weak and inconsistent associations with outcome and variable temporal trends in DENV-specific memory T cell responses between subjects. This study used both ex-vivo and cultured ELISPOT assays to further evaluate the associations between DENV serotype-cross-reactive memory T cells and severity of secondary infection. Using ex-vivo ELISPOT assays, frequencies of memory T cells secreting IFN-γ in response to DENV structural and non-structural peptide pools were low in PBMC from multiple time points prior to symptomatic secondary DENV infection and showed a variable response to infection. There were no differences in responses between subjects who were not hospitalized (NH, n=6) and those who were hospitalized with dengue hemorrhagic fever (hDHF, n=4). In contrast, responses in cultured ELISPOT assays were more reliably detectable prior to secondary infection and showed more consistent increases after infection. Responses in cultured ELISPOT assays were higher in individuals with hDHF (n=8) compared to NH (n=9) individuals before the secondary infection, with no difference between these groups after infection. These data demonstrate an association of pre-existing DENV-specific memory responses with the severity of illness in subsequent DENV infection, and suggest that frequencies of DENV-reactive T cells measured after short-term culture may be of particular importance for assessing the risk for more severe dengue disease.

初级登革热病毒（DENV）感染产生的记忆性 T 细胞被推测可能影响后续 DENV 感染的临床转归。然而，涉及前瞻性收集血液样本的少数研究发现在结局与个体间 DENV 特异性记忆 T 细胞反应的时序趋势方面存在薄弱且不一致的关联。本研究采用了体外和培养的 ELISPOT 分析方法，进一步评估了 DENV 血清型交叉反应性记忆 T 细胞与二次感染严重程度之间的关联。通过体外 ELISPOT 分析，发现多个时间点无症状的二次 DENV 感染的 PBMC 中分泌 IFN-γ 的记忆 T 细胞频率较低，且对感染的反应具有可变性。未住院（NH，n=6）与因登革热出血热（hDHF，n=4）住院的患者之间的反应无差异。相反，在培养的 ELISPOT 分析中，感染前可更可靠地检测到反应，并在感染后显示出更为一致的增加。在感染前，患有 hDHF（n=8）的个体在培养的 ELISPOT 分析中的反应高于 NH（n=9）个体，但在感染后两组之间无差异。这些数据表明，先前存在的 DENV 特异性记忆反应与后续 DENV 感染的疾病严重程度相关联，并暗示在短期培养后测量的 DENV 反应性 T 细胞频率可能对评估更严重登革热疾病的风险具有重要意义。