Rowland R R, Tokuda S
Department of Microbiology, School of Medicine, University of New Mexico, Albuquerque 87131.
Brain Behav Immun. 1989 Jun;3(2):171-4. doi: 10.1016/0889-1591(89)90017-2.
Met-enkephalin (MENK) is an opioid peptide that is released during physiological stress and is reported to either up-regulate or down-regulate the immune response. Our previous experiments showed the ability of 10(-7) M MENK to modulate the plaque-forming cell (PFC) response of Mishell-Dutton cultures treated with low, optimal, and large concentrations of sheep erythrocyte (SE) antigen. In the present series of experiments the PFC response was measured in splenocyte cultures challenged with incremental concentrations of SE in the presence of 10(-7) M MENK. These experiments illustrate what we consider to be true modulation, i.e., the ability of MENK to modulate immune function only during the presence of a strong immune signal. When the immune signal was strong, as represented by a strong PFC response, MENK suppressed the PFC response. Conversely, when the strongest immune signal was high-antigen suppression of the PFC response, MENK overcame the suppression and frequently returned the PFC response to a greater than optimal level. In a true modulatory fashion MENK had no effect in those regions of the dose-response curve where there was insufficient antigen to induce a strong immune signal.
甲硫氨酸脑啡肽（MENK）是一种阿片肽，在生理应激期间释放，据报道它既能上调也能下调免疫反应。我们之前的实验表明，10⁻⁷ M的MENK能够调节用低、最佳和高浓度绵羊红细胞（SE）抗原处理的米舍尔 - 达顿培养物的空斑形成细胞（PFC）反应。在本系列实验中，在存在10⁻⁷ M MENK的情况下，用递增浓度的SE刺激脾细胞培养物，测量PFC反应。这些实验说明了我们所认为的真正的调节作用，即MENK仅在存在强免疫信号时调节免疫功能的能力。当免疫信号很强时，如由强烈的PFC反应所代表，MENK会抑制PFC反应。相反，当最强的免疫信号是PFC反应的高抗原抑制时，MENK会克服这种抑制，并且常常使PFC反应恢复到高于最佳水平。以真正的调节方式，MENK在剂量 - 反应曲线中那些抗原不足以致无法诱导强免疫信号的区域没有作用。
