Gatti L, Guarneri D, Caccamo M L, Gianotti G A, Marini A
Centro Trasfusionale e di Immunoematologia, Istituti Clinici di Perfezionamento, Milano, Italia.
Biol Neonate. 1996;70(6):322-7. doi: 10.1159/000244383.
Platelet function was investigated in full-term infants on the first, the fourth and tenth days of life and compared to normal adult controls. Platelet function was analyzed through a new cytofluorimetric technique with two murine monoclonal antibodies, PAC-1 and anti-GMP-140, directed against two membrane proteins expressed on the activated platelets' surface. The percentage of activated platelets detected with PAC-1 and anti-GMP-140 was evaluated at basal condition and after in vitro stimulation with a weak agonist (ADP) and a strong Txa2 analogue inducer (U 46619). At day 1 platelet activation at basal condition was negligible and similar to adult controls both with PAC-1 (1.2 vs 1.1%) and anti-GMP-140 (2.6 vs. 3.3%). On the contrary, after ADP stimulation the percentage of PAC-1-positive activated platelets was significantly reduced in neonates compared to adults (22 vs. 66%; p < 0.001) and even more after U 46619 (11 vs. 72%; p < 0.001). The percentage of anti-GMP-140-positive activated platelets behaved similarly after adding both ADP (26 vs. 46%; p < 0.01) and U 46619 (37 vs. 67%; p < 0.001). The reduced platelet activation after ADP and U 46619 persisted at day 4 both with PAC-1 and with anti-GMP-140. On the contrary, at day 10 newborn platelets analyzed with anti-GMP-140 behaved similarly to the adult ones both at basal condition and after stimulation with ADP or U 46619 (6 vs. 3% at basal state, 42 vs. 46% after ADP addition, and 55 vs. 67% after U 46619). These data demonstrate that the reduced platelet activation present in newborns is restored by the tenth day after birth.
对足月儿出生后第1天、第4天和第10天的血小板功能进行了研究，并与正常成人对照组进行了比较。通过一种新的细胞荧光技术，使用两种鼠单克隆抗体PAC-1和抗GMP-140，针对活化血小板表面表达的两种膜蛋白来分析血小板功能。在基础状态下以及用弱激动剂（ADP）和强血栓素A2类似物诱导剂（U 46619）进行体外刺激后，评估用PAC-1和抗GMP-140检测到的活化血小板百分比。在第1天，基础状态下的血小板活化可忽略不计，用PAC-1检测时与成人对照组相似（1.2%对1.1%），用抗GMP-140检测时也相似（2.6%对3.3%）。相反，在ADP刺激后，新生儿中PAC-1阳性活化血小板的百分比与成人相比显著降低（22%对66%；p<0.001），在U 46619刺激后更是如此（11%对72%；p<0.001）。加入ADP（26%对46%；p<0.01）和U 46619（37%对67%；p<0.001）后，抗GMP-140阳性活化血小板的百分比表现相似。在第4天，用PAC-1和抗GMP-140检测时，ADP和U 46619刺激后血小板活化降低的情况仍然存在。相反，在第10天，用抗GMP-140分析的新生儿血小板在基础状态下以及用ADP或U 46619刺激后的表现与成人相似（基础状态下6%对3%，加入ADP后42%对46%，加入U 46619后55%对67%）。这些数据表明，新生儿中存在的血小板活化降低在出生后第10天恢复。
