Blumerman Seth L, Herzig Carolyn T A, Wang Fei, Coussens Paul M, Baldwin Cynthia L
Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA 01003, USA.
Mol Immunol. 2007 Mar;44(8):2023-35. doi: 10.1016/j.molimm.2006.09.020. Epub 2006 Nov 1.
Immunization of cattle with a Leptospira borgpetersenii serovar hardjo-bovis vaccine results in the development of a recall response by WC1(+) gammadelta T cells and CD4(+) alphabeta T cells characterized by proliferation and interferon-gamma production. It was hypothesized that these two T cell subpopulations had largely redundant effector functions, principally differing in their requirements for activation. To test this, gene expression in cells proliferating to antigen were compared utilizing RT-PCR and bovine microarrays. Both T cell populations had similar transcript profiles for effector molecules, including IFN-gamma, FasL and granzyme B. In contrast, transcripts for costimulatory receptors and ligands were notably different following activation, as WC1(+) T cells expressed no or lower levels of transcripts for CD28 and CD40L, while CD4(+) T cells expressed substantial levels of both. However, both cell types had high levels of CTLA-4 transcript suggesting the cells may be regulated similarly following activation but differ in their need for and ability to provide costimulation. Microarray analyses to extend the number of genes examined revealed that while both subpopulations upregulated anti-apoptotic genes as well as those involved in cell activation and protein biosynthesis, overall there were limited differences between the two antigen-activated cell populations. Those genes that did differ were involved in cell signaling, protein production and intracellular protein trafficking. These results strengthen the hypothesis that these particular activated WC1(+) and CD4(+) T cells have overlapping effector functions and therefore may differ principally with regard to how they are recruited into immune responses.
用波摩那钩端螺旋体哈氏变种牛疫苗免疫牛，会导致WC1(+) γδ T细胞和CD4(+) αβ T细胞产生回忆反应，其特征为增殖和产生干扰素-γ。据推测，这两个T细胞亚群具有很大程度上冗余的效应功能，主要区别在于它们的激活需求。为了验证这一点，利用逆转录聚合酶链反应（RT-PCR）和牛基因芯片比较了对抗原产生增殖反应的细胞中的基因表达。两个T细胞群体在效应分子的转录谱方面相似，包括干扰素-γ、FasL和颗粒酶B。相比之下，共刺激受体和配体的转录本在激活后明显不同，因为WC1(+) T细胞不表达或低水平表达CD28和CD40L的转录本，而CD4(+) T细胞则大量表达这两种转录本。然而，两种细胞类型都有高水平的CTLA-4转录本，表明细胞在激活后可能受到类似的调节，但在提供共刺激的需求和能力方面存在差异。为扩大所检测基因数量的基因芯片分析表明，虽然两个亚群都上调了抗凋亡基因以及参与细胞激活和蛋白质生物合成的基因，但总体而言，两个抗原激活的细胞群体之间差异有限。那些确实存在差异的基因涉及细胞信号传导、蛋白质产生和细胞内蛋白质运输。这些结果强化了这样的假设，即这些特定的活化WC1(+)和CD4(+) T细胞具有重叠的效应功能，因此可能主要在它们如何被招募到免疫反应方面存在差异。
