Costa R P, Gollob K J, Fonseca L L, Rocha M O, Chaves A C, Medrano-Mercado N, Araújo-Jorge T C, Antas P R, Colley D G, Correa-Oliveira R, Gazzinelli G, Carvalho-Parra J, Dutra W O
Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, MG, Brazil.
Scand J Immunol. 2000 May;51(5):511-9. doi: 10.1046/j.1365-3083.2000.00706.x.
Here, we analysed the use of Vbeta-TCR regions by CD4+ and CD8+ T cells from acute and chronic chagasic patients using flow cytometry. We determined the Vbeta expression in cells freshly isolated from patients, as well as after in vitro stimulation with antigens derived from epimastigote (EPI) or trypomastigote (TRYPO) forms of Trypanosoma cruzi. Analysis of Vbeta-TCR expression of T cells freshly isolated from patients showed a decrease in Vbeta5 expression in the CD4+ T-cell population from acutely infected individuals, whereas CD4+Vbeta5+ T cells were found to be increased in chronic patients with the cardiac, but not indeterminate, clinical form. After culturing peripheral blood mononuclear cells (PBMC) from chronic patients with EPI or TRYPO, we found that both antigenic preparations led to a preferential expansion of CD4+Vbeta5+ T cells. EPI stimulation also led to the expansion of CD8+Vbeta5+ T cells, whereas TRYPO led to the expansion of this cell population only if PBMC were from cardiac and not indeterminate patients. We observed that TRYPO stimulation led to an increase in the frequency of CD4+Vbeta17+ T cells in cultures of PBMC from indeterminate patients, whereas an increase in the frequency of CD8+Vbeta17+ T cells was found upon TRYPO stimulation of PBMC from cardiac patients. Despite this increase in the frequency of Vbeta17+ T-cell populations upon TRYPO stimulation, the same antigenic preparation led to a much higher expansion of Vbeta5+ T cells. These results show a differential expression of Vbeta5-TCR in cells freshly isolated from chagasic patients in different stages of the disease and that parasite-specific antigens stimulate a portion of the T-cell repertoire with preferential usage of Vbeta5-TCR.
在此，我们运用流式细胞术分析了急性和慢性恰加斯病患者的CD4+和CD8+ T细胞对Vβ-TCR区域的使用情况。我们测定了从患者体内新鲜分离出的细胞中的Vβ表达，以及用来自克氏锥虫前鞭毛体（EPI）或 trypomastigote（TRYPO）形式的抗原进行体外刺激后的Vβ表达。对从患者体内新鲜分离出的T细胞的Vβ-TCR表达分析显示，急性感染个体的CD4+ T细胞群体中Vβ5表达降低，而在患有心脏型而非不确定临床型的慢性患者中，CD4+Vβ5+ T细胞有所增加。在用EPI或TRYPO培养慢性患者的外周血单核细胞（PBMC）后，我们发现两种抗原制剂均导致CD4+Vβ5+ T细胞优先扩增。EPI刺激还导致CD8+Vβ5+ T细胞扩增，而只有当PBMC来自心脏型而非不确定型患者时，TRYPO才会导致该细胞群体扩增。我们观察到，TRYPO刺激导致不确定型患者PBMC培养物中CD4+Vβ17+ T细胞频率增加，而心脏型患者PBMC经TRYPO刺激后，CD8+Vβ17+ T细胞频率增加。尽管TRYPO刺激后Vβ17+ T细胞群体频率增加，但相同的抗原制剂导致Vβ5+ T细胞扩增程度更高。这些结果表明，在疾病不同阶段的恰加斯病患者新鲜分离的细胞中，Vβ5-TCR存在差异表达，并且寄生虫特异性抗原刺激了一部分优先使用Vβ5-TCR的T细胞库。
