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

(1)成人CD8+ T细胞CD244阳性比例约为40 ~ 50%，且随着年龄的增长，CD244阳性比例增加，而新生儿CD8+ T细胞几乎为CD244阴性。在三色流式细胞术分析中，CD244阳性细胞中存在CD28/CD62L阳性或阴性两个亚组，而CD244阴性CD8+ T细胞均为CD28阳性CD62L阳性。在传染性单核细胞增多症（IM）和麻疹患者中发现CD244+细胞增多。其中CD28、CD62L阳性、CD244阳性、CD8+ T细胞增多明显。(2)我们分析了cd244阳性和cd244阴性CD8+ T细胞亚群中表面抗原和细胞内细胞毒性颗粒蛋白的表达差异。cd244阴性细胞的表面表型与未处理细胞的表面分子表达几乎相同，也没有表现出颗粒酶B和TIA-1的表达。另一方面，cd244阳性细胞显示了更多的记忆细胞表面表型。(3)幼稚T细胞具有丰富多样性的TCR库，但记忆T细胞的TCR库多样性有限，并分析了cd244阳性和cd244阴性细胞亚组的TCR CDR谱。CD244阴性细胞在所有TCRVβ中呈高斯分布，而CD244阳性细胞在许多TCRVβ中呈偏态划分。此外，CD28阴性细胞和CD62L阴性细胞的CDR3谱复杂性指数比CD28阳性细胞和CD62L阳性细胞的下降幅度更大。(4)体外刺激培养从正常成人CD8+T细胞中分离的cd244阴性CD8+T细胞。我们证实了CD8+ T细胞从cd244阴性表型到cd244阳性表型的转化。CD244的表达在培养早期随着CD3的刺激而增加。另一方面，转换到CD28，CD62L-表型需要两到三周的时间，进展缓慢。(5)通过测定各细胞组分中TREC的含量来量化功能分化期有丝分裂的程度。cd244阴性细胞TREC含量丰富，且TREC含量从CD28CD62L阳性细胞群到CD28/CD62L阴性cd244阳性细胞群依次降低。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