Firestein G S, Reifler D, Richman D, Gruber H E
Department of Medicine, UCSD School of Medicine, San Diego, California 92161.
Cell Immunol. 1988 Apr 15;113(1):63-9. doi: 10.1016/0008-8749(88)90006-8.
The effect of phorbol myristate acetate (PMA) on T4 (CD4) expression by monocytoid cells was studied. Greater than 99% of untreated U937 and HL-60 cells expressed surface T4 as measured with a fluorescence-activated cell sorter. The percentage of T4 positive cells decreased to less than 20% after incubation with PMA (10(-8) M). A decrease was observed within 15 min of PMA exposure, was maximal within 1 hr, and persisted for at least 3 days in the continuous presence of PMA. The susceptibility of untreated and PMA-treated U937 cells to human immunodeficiency virus (HIV) was also studied. Pretreatment of cells with PMA for 18 hr decreased the production of viral RNA and p24 antigen 24 hr after infection. The dose of PMA resulted in a parallel reduction of both T4 expression and infection by HIV. When PMA was washed from cultures and replaced with fresh medium for 48 hr, then T4 expression and the production viral RNA and p24 antigen following infection were restored. These data suggest that pharmacologic manipulation of surface T4 expression may have a potential role in the prevention or treatment of HIV infection.
研究了佛波酯（PMA）对单核细胞样细胞T4（CD4）表达的影响。用荧光激活细胞分选仪检测，超过99%的未处理U937和HL-60细胞表达表面T4。与PMA（10^(-8)M）孵育后，T4阳性细胞百分比降至20%以下。PMA暴露后15分钟内观察到下降，1小时内达到最大，并在PMA持续存在的情况下持续至少3天。还研究了未处理和PMA处理的U937细胞对人类免疫缺陷病毒（HIV）的敏感性。用PMA预处理细胞18小时可降低感染后24小时病毒RNA和p24抗原的产生。PMA的剂量导致T4表达和HIV感染的平行降低。当从培养物中洗去PMA并用新鲜培养基替换48小时后，感染后T4表达以及病毒RNA和p24抗原的产生得以恢复。这些数据表明，表面T4表达的药理学操作可能在预防或治疗HIV感染中具有潜在作用。
