CELLULAR INVESTIGATION AND ANALYSIS OF INDUCTION MECHANISMS OF IN VITRO LANGHANS TYPE-MULTINUCLEATED GIANT CELL FORMATION

刀豆蛋白a刺激人外周血单核细胞上清（条件培养基）生成多核巨细胞（MGC）；朗汉斯型（LGC）和异物型（FGC）。部分细菌肽聚糖的结构类似物MDP （N-acetylmuramyl-L-alanyl-D-isoglutamine）增加了LGC的发生频率。粘附分子和细胞因子如IFN-γ、GM-CSF和IL-3在MGC形成中起重要作用，但在LGC诱导中不起作用。细胞外基质对MGC的形成也很重要，尤其是诱导LGC的细胞纤维连接蛋白。MGC是由cd14 ^<++> CD16单核细胞在条件培养基中产生的，而不是由GM-CSF和IL-4诱导的cd14 ^+CD16^+单核细胞或未成熟树突状细胞产生的，M-CSF诱导的巨噬细胞产生的MGC较少。添加MDP不能产生CD14^+CD16^+单核细胞或树突状细胞的MGC，但可以略微增强巨噬细胞的LGC形成。MDP增强cd14 ^<++> CD16^+单核细胞LGC的融合指数，与整个单核细胞相同。接下来，我们检查了结节病患者单核细胞中MGC的形成。结节病患者单核细胞产生MGC的量高于健康对照组。在条件培养基中培养24小时的结节病患者单核细胞对bz - atp介导的细胞溶解的敏感性明显高于正常人，提示结节病患者单核细胞通过嘌呤能受体产生MGC的能力增强。最后，我们考察了曲尼司特对MGC形成的体外影响。曲尼司特抑制两种MGC的形成呈剂量依赖性。免疫组化染色显示曲尼司特处理的单核细胞ICAM-1表达减少。这些发现表明曲尼司特对某些肉芽肿性疾病的皮肤病变有疗效，部分是通过对单核细胞/巨噬细胞谱系的直接作用。

The supernatant of concanavalin A-stimulated human peripheral blood mononuclear cells (conditioned medium) generated multinucleated giant cells (MGC) ; Langhans type-(LGC) and foreign body type-MGC (FGC). MDP (N-acetylmuramyl-L-alanyl-D-isoglutamine), a structural analogue of part of the bacterial peptidoglycan, augmented the frequency of LGC.Adhesion molecules and cytokines such as IFN-γ, GM-CSF and IL-3 were found to play an important role in MGC formation but not in LGC induction. Extracellular matrix was also important for MGC formation, particularly cellular fibronectin for LGC induction. MGC were produced by conditioned medium from CD 14^<++> CD 16 monocytes but not from CD 14^+CD16^+ monocytes or immature dendritic cells induced by GM-CSF and IL-4, and slightly from macrophages induced by M-CSF.Addition of MDP did not generate MGC from CD14^+CD16^+ monocytes or dendritic cells but slightly enhanced LGC formation from macrophages. Fusion index of LGC from CD 14^<++> CD16^+ monocytes were enhanced by MDP as same as that in whole monocytes. Next, we examined MGC formation from monocytes of patients with sarcoidosis. MGC were more highly produced from monocytes of sarcoidosis patients than healthy control subjects. The susceptibility of monocytes cultured in conditioned medium for 24 hrs to Bz-ATP-mediated cytolysis was significantly higher in sarcoidosis patients than normal subjects, suggesting that the ability of monocytes to produce MGC through purinergic receptors was enhanced in sarcoidosis patients. Finally, we examined the in vitro effect of tranilast on the formation of MGC.Tranilast inhibited the formation of both types of MGC dose-dependently. Immuno-histochemical stainings showed that tranilast-treated monocytes had less expression of ICAM-1. These findings suggest that tranilast has an efficacy for cutaneous lesions in some cases of granulomatous disorders partly through a direct effect on monocyte/macrophage-lineage cells.