宫内生长迟缓早产儿T淋巴细胞亚群水平变化

目的 了解宫内生长迟缓（IUGR）早产儿生后T淋巴细胞亚群水平及变化。方法 67例早产儿中IUGR早产儿29例，适于胎龄（AGA）早产儿38例；另取健康足月儿20例为对照组。采用流式细胞仪测定各组出生24 h内及校正胎龄38周时外周静脉血T淋巴细胞亚群水平；同时测定各时间点外周血白细胞、淋巴细胞及T淋巴细胞绝对计数。结果 24 h内IUGR早产儿CD3+、CD4+百分比低于AGA早产儿和对照组（P<0.05），IUGR 早产儿CD8+及CD4+/CD8+低于对照组（P<0.05），AGA早产儿CD3+、CD4+及CD4+/CD8+低于对照组（P<0.05）；IUGR早产儿外周血淋巴细胞低于对照组（P<0.05），IUGR、AGA早产儿的T淋巴细胞低于对照组（P<0.05），IUGR早产儿T淋巴细胞低于AGA早产儿（P<0.05）。校正胎龄38周时，IUGR、AGA早产儿CD3+、CD4+及CD4+/CD8+高于出生24 h内（P<0.05），IUGR早产儿CD3+、CD4+、CD8+及CD4+/CD8+低于AGA早产儿（P<0.05）；IUGR与AGA早产儿外周血白细胞、淋巴细胞、T淋巴细胞比较差异无统计学意义（P >0.05）。结论 IUGR早产儿T淋巴细胞亚群免疫功能低于AGA早产儿及健康足月儿，并且持续至生后一段时间。

Changes in T lymphocyte subsets in preterm infants with intrauterine growth retardation

Objective To study changes in T lymphocyte subsets in preterm infants with intrauterine growth retardation (IUGR). Methods The study enrolled 29 IUGR preterm infants, 38 preterm infants born appropriate for gestational age (AGA), and 20 healthy full-term infants. Peripheral blood was sampled during the first 24 hours of life, and again at a corrected age of 38 weeks of the preterm infants. T lymphocyte subsets were analyzed by flow cytometry, and absolute counts of leukocytes, total lymphocytes, and T lymphocytes were determined with an automated hematology analyzer. Results Within the first 24 hours of life, percentages of CD3⁺ and CD4⁺ were lower in IUGR preterm infants than in AGA preterm infants and full-term infants (P<0.05), percentages of CD8⁺ and CD4⁺/CD8⁺ ratio were lower in IUGR preterm infants than in full-term infants (P<0.05), and percentages of CD3⁺, CD4⁺ and CD4⁺/CD8⁺ ratio were lower in AGA preterm infants than in full-term infants (P<0.05). Moreover, the absolute counts of total lymphocytes were lower in IUGR preterm infants than in full-term infants (P<0.05); the absolute counts of T lymphocytes were lower in preterm infants, regardless of IUGR, than in full-term infants (P<0.05), and lower in IUGR infants than in AGA infants (P<0.05). At the corrected age of 38 weeks, percentages of CD3⁺, CD4⁺ and CD4⁺/CD8⁺ ratio were increased in both IUGR and AGA infants as compared to the measurements within the first 24 hours of life (P<0.05), and percentages of CD3⁺, CD4⁺, CD8⁺ and CD4⁺/CD8⁺ ratio were lower in IUGR infants than in AGA infants (P<0.05), whereas there were no significant differences in counts of leukocytes, total lymphocytes and T lymphocytes between IUGR and AGA infants (P >0.05). Conclusions There may be a certain degree of compromise in cell-mediated immunity in preterm infants with IUGR and this compromise may last to 38 weeks after birth.