Significance of CD244 expression in functional development of CD8+ cytotoxic T lymphocytes

(1)成人CD8+T细胞约40%~50%呈CD244阳性，且CD244阳性细胞比例随年龄增长而增加，而新生儿CD8+T细胞大部分呈CD244阴性。三色流式细胞仪分析CD244阳性细胞CD28/CD62L阳性或阴性两个亚群，CD244阴性CD8+T细胞CD28阳性CD62L阳性。传染性单核细胞增多症(IM)和麻疹患者外周血中CD244+细胞明显增多，与正常人比较，尤以CD28、CD62L阳性、CD244阳性的CD8+T细胞明显增多。(2)分析CD244阳性和CD244阴性的CD8+T细胞亚群表面抗原和细胞内细胞毒颗粒蛋白表达的差异。CD244阴性细胞的表面分子表达与初代细胞几乎相同，也不表达PERACT、颗粒酶B、TIA-1。另一方面，CD244阳性细胞向我显示…(3)初始T细胞具有丰富的多样性的TCR谱系，但记忆性T细胞的T细胞谱多样性预计有限，并分析了CD244阳性和CD244阴性的每个细胞亚群的TCR CDR谱。CD244阴性细胞在所有TCRVβ中呈正态分布，但CD244阳性细胞在许多TCRVβ中呈偏斜分布。此外，CD28阴性细胞和CD62L阴性细胞的CDR3谱的复杂性指数均低于CD28阳性细胞和CD62L阳性细胞。(4)从正常成人CD8+T细胞中分离出CD244阴性的CD8+T细胞进行体外刺激和培养。我们证实了CD8+T细胞从CD244阴性表型向CD244阳性表型转化。CD244的表达在培养早期随CD3的刺激而增加。另一方面，向CD28、CD62L-表型转化需要2~3周时间，进展缓慢。(5)检测各细胞分级中TREC含量以量化功能分化期有丝分裂的程度。CD244阴性细胞显示丰富的TREC含量，TREC含量按CD28CD62L阳性CD244阳性细胞、CD28/CD62L阴性CD244阳性细胞数量递减。较少

(1) About 40-50% adult CD8+ T cell were CD244 positive and CD244 positive fraction increased with aging whereas almost of newborn infant CD8+ T cell was CD 244 negative. CD28/CD62L positive, or negative two subgroup were present in CD244 positive cells when they analyzed three-color flow cytometry, whereas all CD244 negative CD8+ T cells were CD28 positive CD62L positive. Increase of CD244+ cells have been found in patients with infectious mononucleosis (IM) and measles., compared it with a normal subject, and in particular, and increase of CD28,CD62L positive CD244 positive CD8+ T cell were prominent.(2) We analyzed the difference of expression of surface antigen and intracellular cytotoxic granular proteins in CD244-positive, and CD244-negative CD8+ T cell subgroup. CD244-negative cells showed surface phenotype almost same as naive cell from all surface molecule expression and did not show perform, granzyme B, TIA-1 expression either. On the other hand, CD244-positive cells showed me … More mory cell surface phenotype.(3) Naive T cell have TCR repertoire with full of diversity, but T cell repertoire diversity was expected to be limited in memory-T cells, and TCR CDR spectrum were analyzed in each CD244-positive, CD244-negative cell subgroup. CD244 negative cells presented Gaussian distribution in all TCRVβ, but CD244-positive demarcation showed a skewed pattern in many TCRVβ. In addition, complexity index of CDR3 spectra in CD28-negative cell or CD62L negative cell decreased more than that in CD28 positive cells, or CD62L positive cell.(4) CD244-negative CD8+ T cell separated from normal adult CD8+T cells were stimulated and incubated, in vitro. We confirmed conversion from CD244-negative to CD244-positive phenotypte in CD8+ T cells. CD244 expression were increased with CD3 stimulation at early stage of culture. On the other hand, switch to CD28,CD62L- phenotype took two or three weeks and progressed in slowly.(5) We measured TREC content in each cell fractionation to quantify degree of mitosis in functional differentiation phase.CD 244 negative cells showed abundant TREC content, and the TREC content decreased in order of CD28CD62L positive CD244-positive cells, CD28/CD62L negative CD244-positive cell populations. Less