Spaner D, Cohen B L, Miller R G, Phillips R A
Division of Immunology and Cancer Research, Hospital for Sick Children, Toronto, Canada.
J Immunol. 1995 Oct 15;155(8):3866-76.
The function of gamma delta T cells, particularly the minor population of circulating gamma delta T cells, remains unclear. To study these lymphoid gamma delta T cells, a transgenic SCID mouse containing the KN6 gamma delta TCR whose ligand is the TL gene product, T22b, was created. KN6-SCID mice contain a monoclonal population of naive KN6+ gamma delta T cells. Using these mice, we have studied the APC required for activation of KN6+ gamma delta T cells in vitro and in vivo. Analysis of an in vitro mixed lymphocyte response identified a hierarchy of potency for stimulation: dendritic cells = T cell blasts > B cell blasts > B cells > resting T cells. In contrast, in vivo, only alpha beta T cells fully activated KN6+ gamma delta T cells as measured by an increase in the number of splenic KN6+ cells, the development of blast morphology, and the development of proliferative anergy in the responding KN6+ cells. The strong stimulatory properties of C57BL/6J T cells appeared to depend on their having been activated by KN6-SCID alloantigens. T cells from (C57BL/6J x BALB/c)F1 mice, which are tolerant of KN6-SCID alloantigens, could not fully activate KN6+ cells. However, the F1 T cells could activate KN6+ cells if they were activated in vivo by the mitogen, staphylococcal enterotoxin B. A mixture of third party activated T cells plus T22b+ non-T cells only partially activated KN6+ cells, implying that activated T22b+ T cells are acting directly as stimulatory cells. Although the Ags recognized by gamma delta T cells are generally unknown, Ag presentation by activated alpha beta T cells may be an important method of activation.
γδT细胞的功能，尤其是循环γδT细胞中的少数群体，仍不清楚。为了研究这些淋巴细胞γδT细胞，构建了一种含有KN6γδTCR的转基因SCID小鼠，其配体是TL基因产物T22b。KN6-SCID小鼠含有单克隆群体的幼稚KN6 +γδT细胞。利用这些小鼠，我们研究了体外和体内激活KN6 +γδT细胞所需的抗原呈递细胞（APC）。对体外混合淋巴细胞反应的分析确定了刺激效力的层次结构：树突状细胞=T细胞母细胞>B细胞母细胞>B细胞>静息T细胞。相比之下，在体内，只有αβT细胞能完全激活KN6 +γδT细胞，这通过脾中KN6 +细胞数量的增加、母细胞形态的发展以及反应性KN6 +细胞中增殖无能的发展来衡量。C57BL/6J T细胞的强刺激特性似乎取决于它们被KN6-SCID同种异体抗原激活。来自（C57BL/6J×BALB/c）F1小鼠的T细胞，它们对KN6-SCID同种异体抗原耐受，不能完全激活KN6 +细胞。然而，如果F1 T细胞在体内被丝裂原葡萄球菌肠毒素B激活，它们就能激活KN6 +细胞。第三方激活的T细胞加T22b +非T细胞的混合物只能部分激活KN6 +细胞，这意味着激活的T22b + T细胞直接作为刺激细胞起作用。尽管γδT细胞识别的抗原通常未知，但激活的αβT细胞的抗原呈递可能是一种重要的激活方法。
