文本框: PRELIMINARY OBSERVATION OF APOPTOTIC FEATURE OF T LYMPHOCYTE IN PRETERM NEONATES Zhang Qiuye, Shan Yanchun, Dong Zengyi, Wei Shuzhen. Affiliated Hospital of Qingdao University Medical College, Qingdao, China Objective: To study the features and its effect factor of T lymphocyte apoptosis in preterm neonates Methods: The susceptibility to apoptosis of T lymphocytes were determined in 49 neonates (19 preterm) by percentage calculation of apoptosis cells and DNA fragmentation analysis. The expression of CD25 (IL-2R) and CD38 in peripheral blood mononuelear cells and the volume of IL-2 and IL-6 produced by lymphocytes incubated for 48h was determined by immunofluoscence procedure and ELISA. Results: T lymphocyte apoptosis was more easily in preterm than in term neonates (p<0.001),and the apoptotic cell percentage was negatively correlated with gestational age and the volume of IL-6 produced by lymphocytes in preterm neonates, respectively. (r=-0.52, -0.49, p<0.05). The apoptotic cell percentage at incubating 48h was positively correlated with the expression of CD38 (preterm:r=0.70; term: r=0.74, p<0.01), but negatively with the expression of CD25 (preterm:r=-0.62; term: r=-0.88, p<0.01). Remarkably decreased volume of IL-2 and IL-6 produced by lymphocyte in preterm neonates was found in comparison with those from term neonates(p<0.001) . Conclusion: Enhanced susceptibility to apoptosis is another important character of T lymphocyte dysfunction in neonates; and the smaller the gestational age, the more enhanced susceptibility to apoptosis. The reasons may be included in the immature phenotype, the insufficient activity of cells, and the decreased production of IL-6 and IL-2. 0702