甲硫脑啡肽对人单核细胞抗原提呈功能的影响

Effect of methione-enkephalin on antigen-presenting capability of human monocytes

将提纯的人单核细胞(Mon)与纯化蛋白衍生物(PPD)和甲硫脑啡肽(M—ENK)共同温育24小时后.观察Mon向同体T淋巴细胞(T)提呈PPD的能力。结果表明,接近生理血浓的M—ENK(10 ^(10)(?)10^(-14)M)能促进T的增殖反应(P<0.01),这种作用可被10^(-6)M的纳络酮所对消。远高于生理血浓的M—ENK(10(-4)～10^(-6)M)则能抑制T的增殖反应(P<0.01)。

Mononuclear cells separated from heparinized fresh venous blood of healthy male blood clonors by means of Ficoll- Hypaque density gradient centrifugation were subjected to petri dish adhesion and nylon wool-column separation to obtain monocytes and T lymphocytes of high purity, respectively. Antigen- presenting capability of the monocytes, as reflected by T lymphocyte proliferation, was assayed after the monocytes had been preincubated with PPD (purified protein derivative, end concentration12.5 μg /ml ) and methione enkephalin (M-Enk) in defferent concentrations for 24 hours at 37 ℃ in a humidified incubator containing 5% CO_2. It was shown that the antigen-presenting capability of the monocytes was markedly enhanced by M-Enk when its concentration was from 10 ^(-10) M to 10^(-14) M(close to the normal serum concentration of M-Enk), and this effect of M-Enk could be cancelled if the monocytes had been pretreated with 10^(-6) M naloxone for 30 min before addition of PPD and M-Enk, suggesting that the effect of M-Enk in these concentrations was mediated through the opioid receptors on the monocytes. M-Enk in high concentrations (10^(-4) M-10^(-6)), however, was found to inhibit th'e antigen- presenting capability significantly and this inhibition could not be cancelled by pretreatment of the monocytes with naloxone.