Lantero S, Oddera S, Silvestri M, Ottolini V, Sacco O, Rossi G A
Division of Pneumology, G. Gaslini Institute, Genoa, Italy.
Monaldi Arch Chest Dis. 1993;48(1):29-33.
Thymomodulin, a calf thymus derivative, is able to stimulate T-lymphocytes and monocytes, and to activate phagocytes and their precursors. However, it is not fully understood whether the effect of thymomodulin on phagocytic cells is a direct stimulation, or a phenomenon mediated by cytokines released by mononuclear cells. To answer this question, we first evaluated the effects of thymomodulin on the phagocytosis and intracellular killing of Staphylococcus aureus by blood polymorphonuclear cells (PMNs), cultured with or without autologous mononuclear cells. Secondly, during the processes of phagocytosis and intracellular killing, we evaluated the release by PMNs of chemotactic factors for PMNs, lymphocytes and monocytes. No difference was found in the phagocytosis and killing processes when PMNs were incubated alone or with autologous mononuclear cells (p > 0.05, each comparison). Thymomodulin was able to increase the phagocytosis process when PMNs were incubated with lymphocytes and monocytes (p = 0.05), and to enhance the killing by PMNs cultured alone (p = 0.05), or cultured with autologous mononuclear cells (p < 0.05). The release of chemotactic factors for PMNs, lymphocytes and monocytes in the supernatants of the phagocytosis experiments, was higher when PMNs were incubated with mononuclear cells, compared to cultures of PMNs alone (p < 0.05, each comparison); and thymomodulin did not increase their release without the presence of autologous mononuclear cells in the cultures (p > 0.05 each comparison). These data suggest that thymomodulin acts upon PMNs, inducing mononuclear cells to release factors able to stimulate the phagocytosis and the intracellular killing of exogenous organisms, but does not amplify the immune reaction enhancing further leucocytes recruitment.
胸腺调节素是一种小牛胸腺衍生物，能够刺激T淋巴细胞和单核细胞，并激活吞噬细胞及其前体。然而，胸腺调节素对吞噬细胞的作用是直接刺激，还是由单核细胞释放的细胞因子介导的现象，目前尚不完全清楚。为了回答这个问题，我们首先评估了胸腺调节素对血液多形核细胞（PMN）吞噬和细胞内杀灭金黄色葡萄球菌的影响，这些PMN在有或没有自体单核细胞的情况下进行培养。其次，在吞噬和细胞内杀灭过程中，我们评估了PMN释放的对PMN、淋巴细胞和单核细胞的趋化因子。当PMN单独孵育或与自体单核细胞一起孵育时，在吞噬和杀灭过程中未发现差异（每次比较p>0.05）。当PMN与淋巴细胞和单核细胞一起孵育时，胸腺调节素能够增加吞噬过程（p=0.05），并增强单独培养的PMN（p=0.05）或与自体单核细胞一起培养的PMN的杀灭能力（p<0.05）。与单独培养的PMN相比，当PMN与单核细胞一起孵育时，吞噬实验上清液中对PMN、淋巴细胞和单核细胞的趋化因子释放更高（每次比较p<0.05）；在培养物中没有自体单核细胞存在的情况下，胸腺调节素不会增加它们的释放（每次比较p>0.05）。这些数据表明，胸腺调节素作用于PMN，诱导单核细胞释放能够刺激吞噬和细胞内杀灭外源生物体的因子，但不会放大免疫反应以进一步增强白细胞募集。
