A Cytokine-Independent Approach To Identify Antigen-Specific Human Germinal Center T Follicular Helper Cells and Rare Antigen-Specific CD4+ T Cells in Blood.
A Cytokine-Independent Approach To Identify Antigen-Specific Human Germinal Center T Follicular Helper Cells and Rare Antigen-Specific CD4+ T Cells in Blood.
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DOI：
10.4049/jimmunol.1600318
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发表时间：
2016-08-01
期刊：
影响因子：
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通讯作者：
Crotty S
中科院分区：
文献类型：
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作者：
Dan JM;Lindestam Arlehamn CS;Weiskopf D;da Silva Antunes R;Havenar-Daughton C;Reiss SM;Brigger M;Bothwell M;Sette A;Crotty S
检测抗原特异性的CD4+T细胞是许多人类传染病、疫苗和自身免疫性疾病研究的核心。然而，这类细胞通常是罕见的，并且在其细胞因子谱上是异质性的。通过细胞因子的产生来鉴定抗原特异性生发中心(GC)T滤泡辅助细胞(TFH)一直是一个特别有问题的问题。GC Tfh细胞的功能是通过同源相互作用选择性地帮助相邻的GC B细胞；因此，GC Tfh细胞可能是“吝啬的”细胞因子产生者，在产生细胞因子的数量上与Th1或Th17细胞根本不同。传统的通过细胞内细胞因子染色(ICS)鉴定抗原特异性细胞依赖于CD4+T细胞产生大量细胞因子的能力。为了解决这个问题，我们开发了一种细胞因子非依赖的激活诱导标记(AIM)方法来鉴定人类淋巴组织中抗原特异性的GC Tfh细胞。虽然A组链球菌(Strep)特异性GC Tfh细胞产生的细胞因子最少，但AIM方法识别的抗原特异性GC Tfh细胞要高出85倍。有趣的是，这些GC Tfh细胞在激活时持续表达程序性死亡配体1(PD-L1)。AIM还在淋巴组织中检测到非Tfh细胞。因此，我们将AIM应用于人外周血中稀有抗原特异性的CD4+T细胞的鉴定。AIM可以很容易地检测到登革热、结核病和百日咳疫苗特异性的CD4+T细胞。总之，细胞因子分析遗漏了98%的抗原特异的人类GC Tfh细胞，反映了这些细胞的生物学特性，而这些细胞可以通过TCR依赖的激活标记的共同表达来敏感地鉴定。
Detection of antigen-specific CD4+ T cells is central to the study of many human infectious diseases, vaccines, and autoimmune diseases. However, such cells are generally rare and heterogeneous in their cytokine profiles. Identification of antigen-specific germinal center (GC) T follicular helper (Tfh) cells by cytokine production has been particularly problematic. The function of a GC Tfh cell is to selectively help adjacent GC B cells via cognate interaction; thus, GC Tfh cells may be ‘stingy’ cytokine producers, fundamentally different than Th1 or Th17 cells in the quantities of cytokines produced. Conventional identification of antigen-specific cells by intracellular cytokine staining (ICS) relies on the ability of the CD4+ T cell to generate substantial amounts of cytokine. To address this problem, we have developed a cytokine-independent activation induced marker (AIM) methodology to identify antigen-specific GC Tfh cells in human lymphoid tissue. Whereas Group A Streptococcus (Strep)-specific GC Tfh cells produced minimal detectable cytokines by ICS, the AIM method identified 85-fold more antigen-specific GC Tfh cells. Intriguingly, these GC Tfh cells consistently expressed programmed death ligand 1 (PD-L1) upon activation. AIM also detected non-Tfh cells in lymphoid tissue. As such, we applied AIM for identification of rare antigen-specific CD4+ T cells in human peripheral blood. Dengue-, tuberculosis-, and pertussis-vaccine-specific CD4+ T cells were readily detectable by AIM. In sum, cytokine assays missed 98% of antigen-specific human GC Tfh cells, reflecting the biology of these cells, which could instead be sensitively identified by co-expression of TCR-dependent activation markers.