胆红素对新生儿脐血单核细胞表面分子Toll样受体4的影响

目的：探讨不同浓度胆红素对新生儿脐血单核细胞（CBMC）表面分子Toll样受体4（TLR4）的影响。方法：采用纤维连接蛋白结合法分离得到CBMC，将其加入含不同浓度胆红素（0~307.8 μmol/L）的牛血清白蛋白溶液中孵育1 h，再加入脂多糖（LPS，1 μg/mL）刺激24 h。收集CBMC，采用间接免疫荧光技术检测细胞表面分子TLR4的表达。结果：胆红素浓度为102.6、153.9、 220.6和307.8 μmol/L时，CBMC表面分子TLR4 的表达率均明显降低，随着胆红素浓度的升高，这种降低趋势越明显。结论：胆红素抑制CBMC表面分子TLR4的表达，随着胆红素浓度的升高，抑制作用越明显。

Effect of bilirubin on expression of toll-like receptor 4 in cord blood monocytes

Objective To study the effect of different concentrations of bilirubin on expression of toll-like receptor 4(TLR4) in cord blood monocytes(CBMC).Methods Under the sterile condition,umbilical vein blood samples were obtained from normal full-term newborns,and the monocytes were in vitro separated by the method of gelatin/plasma coated flasks.The monocytes were preincubated with various concentrations(0-307.8μmol/L) of bilirubin dissolved in bovine albumin solution for 1 hr.Bilirubin-treated CBMC were further cultured with LPS(1μg/mL) to induce cellular activation for 24 hrs,and then the CBMC were collected.The expression of TLR4 in monocytes was measured by indirect immunofluorescence method.Results Bilirubin at the concentrations of 102.6,153.9,220.6 and 307.8 μmol/L inhibited the expression of TLR4 of CBMC.The inhibition effect increased with the increasing concentration of bilirubin.Conclusions Bilirubin can inhibit the TLR4 expression of CBNC in a dose-dependent manner.