Yao L J, Fraher L J, Veldhuizen R A, Samuelson S, Borron P, Malloy J, McCaig L, Lewis J F
Department of Medicine, The Lawson Research Institute, The University of Western Ontario, London, Canada.
Biochim Biophys Acta. 2001 Mar 26;1535(3):266-74. doi: 10.1016/s0925-4439(01)00023-0.
The effects of alveolar large aggregate (LA) and small aggregate (SA) surfactant subfractions isolated from healthy adult rats on mitogen-stimulated proliferative responses of human peripheral blood mononuclear cells (PBMC) was examined. Various concentrations of total surfactant suppressed proliferation of stimulated lymphocytes by up to 95% of mitogen-stimulated cells alone. LA subfractions of total surfactant had no effect on proliferation, whereas SA significantly enhanced the lymphocyte proliferation at lower concentrations (7.8 microg/ml) compared to mitogen-stimulated cells alone. Higher concentrations of SA (62.5 microg/ml) inhibited lymphocyte proliferation. This concentration-dependent effect of SA on proliferation of PBMC was also present when cells were stimulated with various lectins including anti-CD3, concanavalin A and phytohemagglutinin. Analysis of the supernatant of mitogen-stimulated cell cultures treated with inhibitory concentrations of SA showed decreased amounts of interleukin (IL)-2, compared to cells alone, which could be reversed by adding exogenous IL-2 to the cell cultures with the SA. These results suggest that alveolar surfactant subfractions have distinct functions within the alveoli, both biophysically and with respect to their effects on the host's immunomodulatory responses.
研究了从健康成年大鼠分离出的肺泡大聚集体（LA）和小聚集体（SA）表面活性物质亚组分对人外周血单个核细胞（PBMC）有丝分裂原刺激的增殖反应的影响。不同浓度的总表面活性物质单独作用时，可使受刺激淋巴细胞的增殖受到抑制，抑制程度高达有丝分裂原刺激细胞的95%。总表面活性物质的LA亚组分对增殖无影响，而SA在较低浓度（7.8微克/毫升）时与单独有丝分裂原刺激的细胞相比，显著增强了淋巴细胞增殖。较高浓度的SA（62.5微克/毫升）则抑制淋巴细胞增殖。当用包括抗CD3、刀豆球蛋白A和植物血凝素在内的各种凝集素刺激细胞时，SA对PBMC增殖的这种浓度依赖性效应也存在。用抑制浓度的SA处理有丝分裂原刺激的细胞培养上清液分析显示，与单独细胞相比，白细胞介素（IL）-2的量减少，在细胞培养物中加入外源性IL-2可逆转SA处理组的这种情况。这些结果表明，肺泡表面活性物质亚组分在肺泡内具有不同的功能，包括生物物理功能以及它们对宿主免疫调节反应的影响。
