Hogg Alison E, Parsons Keith, Taylor Geraldine, Worth Andrew, Beverley Peter, Howard Christopher J, Villarreal-Ramos Bernardo
Institute for Animal Health, Compton, Nr. Newbury, Berkshire, RG20 7NN, UK.
Vet Immunol Immunopathol. 2011 Mar 15;140(1-2):47-54. doi: 10.1016/j.vetimm.2010.11.012. Epub 2010 Nov 19.
Evaluation of the changes induced by immunological interventions requires a baseline against which to compare those changes. The age-related changes in the CD8(+) T-cell population of cattle were studied. The results indicate that CD8(+) T-cells could be divided into γ/δ TCR1(+) and γ/δ TCR1(-) according to their expression of the γ/δ T-cell receptor. As a proportion, the CD8(+) γ/δ TCR1(+) population appears to increase with age. Within the CD8(+)γ/δ TCR1(-) a population of cells expressing a profile of surface molecules previously associated with effector memory T cells (CD45RO(+), CD62L(-), CD27(-), CD45RA(-) and CD28(-)) increases with age. Furthermore, a parallel increase with age in the proportion of CD8(+)CD45RO(+) T cells that express the cytotoxic granule protein perforin was observed. In peripheral tissues, namely lungs, it was found that the majority of CD8(+) T cells present expressed a phenotype indicative of previously primed T cells (high expression of CD45RO and perforin). In contrast, only a small population of memory CD8(+) T cells was present in lymphoid tissue where most of the CD8(+) T cells expressed a naïve phenotype. In conclusion, in cattle, like in human, CD8(+) T cells that express a phenotype associated with antigen experience accumulate with age that may play a role in immunocompetence as the individual ages.
评估免疫干预引起的变化需要一个基线来与这些变化进行比较。研究了牛CD8(+) T细胞群体的年龄相关变化。结果表明，CD8(+) T细胞可根据其γ/δ T细胞受体的表达分为γ/δ TCR1(+)和γ/δ TCR1(-)。作为一个比例，CD8(+)γ/δ TCR1(+)群体似乎随着年龄的增长而增加。在CD8(+)γ/δ TCR1(-)内，一群表达先前与效应记忆T细胞相关的表面分子谱(CD45RO(+)、CD62L(-)、CD27(-)、CD45RA(-)和CD28(-))的细胞随着年龄的增长而增加。此外，观察到随着年龄的增长，表达细胞毒性颗粒蛋白穿孔素的CD8(+)CD45RO(+) T细胞比例平行增加。在外周组织，即肺中，发现存在的大多数CD8(+) T细胞表达一种表明先前已致敏T细胞的表型(CD45RO和穿孔素高表达)。相反，在淋巴组织中仅存在少量记忆性CD8(+) T细胞，其中大多数CD8(+) T细胞表达幼稚表型。总之，在牛中，与人类一样，表达与抗原经历相关表型的CD8(+) T细胞随着年龄的增长而积累，这可能在个体衰老时的免疫能力中发挥作用。
