Baughman R P, Mangels D J, Strohofer S, Corser B C
J Lab Clin Med. 1987 Jun;109(6):692-7.
The surface active material (SAM) of alveolar lining fluid has been shown to have immunologic activity. We studied the effect of SAM on monocyte-macrophage cytotoxicity against a tumor cell line. Alveolar macrophages were studied from 15 subjects without cancer. Tumor growth, as assessed by tritiated thymidine incorporation, was significantly inhibited by the macrophages alone (tumor alone median 39,401 cpm, macrophages plus tumor median 12,153 cpm, P less than 0.01). Tumor cytotoxicity was enhanced by preincubating the macrophages with lipopolysaccharide (median 37 cpm, P less than 0.01) or coincubating the tumor cells and macrophages with SAM (median 5474 cpm, P less than 0.01). Similar results were seen when using blood adherent mononuclear cells. There was increasing cytotoxicity for the adherent mononuclear cells with increasing amounts of SAM. When the various phospholipids of SAM were studied, it was found that phosphatidylcholine, sphingomyelin, and phosphatidyl glycerol all enhanced adherent mononuclear cell cytotoxicity, whereas phosphatidylinositol inhibited adherent mononuclear cell cytotoxicity. These studies suggest that SAM may have important immunoregulatory function for the alveolar macrophage.
肺泡衬液中的表面活性物质（SAM）已被证明具有免疫活性。我们研究了SAM对单核细胞 - 巨噬细胞针对肿瘤细胞系的细胞毒性的影响。对15名无癌症受试者的肺泡巨噬细胞进行了研究。通过氚标记胸腺嘧啶核苷掺入评估的肿瘤生长，仅巨噬细胞就显著抑制了肿瘤生长（仅肿瘤组中位数为39,401 cpm，巨噬细胞加肿瘤组中位数为12,153 cpm，P小于0.01）。通过用脂多糖预孵育巨噬细胞（中位数为37 cpm，P小于0.01）或使肿瘤细胞和巨噬细胞与SAM共同孵育（中位数为5474 cpm，P小于0.01），可增强肿瘤细胞毒性。使用血液黏附单核细胞时也观察到类似结果。随着SAM量的增加，黏附单核细胞的细胞毒性增强。当研究SAM的各种磷脂时，发现磷脂酰胆碱、鞘磷脂和磷脂酰甘油均增强了黏附单核细胞的细胞毒性，而磷脂酰肌醇则抑制了黏附单核细胞的细胞毒性。这些研究表明，SAM可能对肺泡巨噬细胞具有重要的免疫调节功能。
