經體外受精及胚胎植入後反覆著床失敗的女性週邊血液CD4+CD25bright T細胞之數量較低

Decreased circulating CD4+CD25bright T cells in women with repeated implantation failures after in vitro fertilization and embryo transfer

目的：研究經體外受精及胚胎植入後反覆著床失敗的女性，反覆性流產的女性及具有正常生殖能力的女性在非懷孕狀態下周邊血液中的CD4+CD25bright T細胞。方法：以流式細胞儀來測量25位經體外受精及胚胎植入後反覆著床失敗的女性，18位反覆性流產的女性及21位具有正常生殖能力的女性周邊血液中CD4+CD25bright T細胞之比率。結果：反覆性著床失敗女性周邊血液中之CD4+CD25bright T細胞之比率（中位數 = 3.95%，四分位差 = 2.25-5.70%）和其在對照組女性（中位數 = 5.39%，四分位差 = 4.36-6.74%，p值小於0.0083）比起來明顯較低。反覆著床失敗女性周邊血液中之CD4+CD25bright T細胞之絕對數量（中位數 = 24.5 細胞／微升 ，四分位差 = 12.9-32.0 細胞/微升）和其在對照組女性（中位數 = 36.6 細胞／微升，四分位差 = 23.8-44.2 細胞／微升，p值小於0.0083）比起來顯著較低。在排除曾經發生流產的反覆著床失敗女性後，反覆性著床失敗女性周邊血液中之CD4+CD25bright T細胞之比率及絕對數量皆顯著較低（兩者p值皆小於0.0167）。結論：反覆性著床失敗女性周邊血液中之CD4+CD25bright T細胞之數量較低可能和著床失敗之致病機轉有相關。

Objective: To investigate peripheral blood CD4+CD25bright T cells in non-pregnant women with repeated implantation failures (RIFs) after two or more in vitro fertilization and embryo transfer (IVF-ET) cycles, those with recurrent spontaneous abortion (RSA) and those with normal fertility (controls). Methods: Proportions of circulating CD4+CD25bright T cells within CD4+ T cells and absolute numbers of CD4+CD25bright T cells in 25 women with RIF, 18 women with RSA and 21 controls were determined by flow cytometric analysis. Results: Significantly lower proportions of peripheral blood CD4+CD25bright T cells within CD4+ T cells were observed in women with RIF (median = 3.95%, interquartile [IQ] range 2.52-5.70%) than those in controls (median = 5.39%, IQ range 4.36-6.74%, p<0.0083). Significantly lower absolute numbers of peripheral blood CD4+CD25bright T cells were observed in women with RIF (median = 24.5 cells/μL, IQ range 12.9-32.0 cells/μL) than those in controls (median = 36.6 cells/μL, IQ range 23.8-44.2 cells/μL, p<0.0083). After excluding women with RIF with a history of RSA, the proportions and the absolute numbers of peripheral blood CD4+CD25bright T cells were still significantly lower than those in controls (p<0.0167 for both). Conclusion: Decreased peripheral blood CD4+CD25bright T cells in women with RIF may be involved in the pathogenesis of implantation failures.