老年人T细胞膜型CD28及血清中可溶性CD28的表达及其意义

Expression and its significance of the membrane CD28 in T cells and the serum level of soluble CD28 in elders

分析老年人(年龄在60岁以上)外周血T细胞膜型CD28(mCD28)及血清中可溶性CD28(sCD28)的表达水平,探讨该分子在老年人免疫功能改变中的意义。分别收集肝素抗凝及不抗凝的老年人外周血,抗凝血经分离获取单个核细胞,间接免疫荧光及流式细胞仪分析,老年人T细胞mCD28的阳性表达率为男性(41.56%±11.23%)及女性(42.97%±12.02%)。与年轻人[男性(61.51%±17.45%)及女性(62.38%±16.22%)]相比,差别具有显著性(P<0.01)。酶联免疫吸附法(ELISA)检测,老年人血清中sCD28的含量为男性(1.08±0.45)及女性(0.98±0.47)ng/ml,与青年人[男性(0.55±0.16)及女性(0.52±0.13)ng/ml]相比,差别具有显著性(P<0.01)。老年人T细胞mCD28的表达水平下降,而血清中sCD28的含量升高。

The membrane form of CD28 in T cells and the serum level of soluble CD28 from peripheral blood of elders（beyond age of 60） were analysed in order to clarify its significance in the changes of immune functions in elders. The methods for detecring the membrane CD28 in T cells and the levels of sobuble CD28 in peripheral blood were FACS analysis and ELISA assay respectively. Meanwhile, the changes on positive rates of membrane CD28 and the concentrations of soluble CD28 along with the change in age and sex were analysed with statistics. It was found that the expression rates of membrane CD28 in T cells of elders were 41.56 % ± 11.23 % in male and 42. 97 ± 12. 025 in female respectively compared with those of young men （61.51 ± 17.45%） and young women（62.38% ± 16.22%）, it showed significant differences. As demonstrated by ELISA assay, compared with the concentrations of serum soluble CD28 in male elders（1.08 ±0.45）ng/ml and female elders（0.98 ±0.47）ng/ml as well as young men（0.55±0.16）ng/ml and young women（0.52 % ±0.13 %）, significant differences also existed. It is evident that in ease of elders the expression of menbrane CD28 in T cells reduces, while the serum level of soluble CD28 elevates significantly.