el-Shahat A S, Saad S O
Plastic, Reconstructive and Burn Unit, Faculty of Medicine, Mansoura University, Egypt.
Burns. 1999 Aug;25(5):395-401. doi: 10.1016/s0305-4179(98)00164-8.
Polymorphonuclear leukocytes (PMLs) play a key role in host defense, and phagocyte dysfunction has been associated with increased susceptibility to infections in patients with thermal injury. Intercellular adhesion molecule-1 (ICAM-1) plays a role in leukocyte accumulation and extravasation. Therefore, the aim of the present study was to assess the PMLs expression of opsonin receptors: Fc gamma RIII, CR1 and CR3; opsonophagocytosis of PMLs and plasma soluble ICAM-1. Flow cytometric analysis (FCM) was used to study PMLs expression of IgG Fc-receptor III (Fc gamma RIII) as well as the complement receptors CR1 (receptor for C3b) and CR3 (receptor for C3bi) in 23 patients with large burns. Analysis of PML complement- and immunoglobulin-mediated phagocytosis of Candida albicans were performed in parallel using the phagocytic index. Plasma sICAM-1 was determined using ELISA. This study revealed a significant increase, with variable degrees, in CR1 and CR3-dependent fluorescence, complement-mediated phagocytosis of C. albicans and plasma sIGAM-1 that started at day 2 and remained for about 20 days before normalization. In contrast, Fc gamma RIII-dependent fluorescence and Ig-mediated phagocytosis were significantly decreased versus the control values. These results demonstrate significant changes of PMLs opsonin receptors expression and opsonophagocytosis documenting systemic activator of PMLs after large burns. In addition, elevation of plasma sICAM-1 may enhance the harmful effect of neutrophil activation through leukocyte accumulation and extravasation through endothelial damage in skin and in lung.
多形核白细胞（PMLs）在宿主防御中起关键作用，吞噬细胞功能障碍与热损伤患者感染易感性增加有关。细胞间黏附分子-1（ICAM-1）在白细胞聚集和外渗中起作用。因此，本研究的目的是评估调理素受体：FcγRIII、CR1和CR3在PMLs中的表达；PMLs的调理吞噬作用以及血浆可溶性ICAM-1。采用流式细胞术（FCM）研究23例大面积烧伤患者中IgG Fc受体III（FcγRIII）以及补体受体CR1（C3b受体）和CR3（C3bi受体）在PMLs中的表达。同时使用吞噬指数对白色念珠菌的PML补体和免疫球蛋白介导的吞噬作用进行分析。采用ELISA法测定血浆sICAM-1。本研究显示，CR1和CR3依赖性荧光、白色念珠菌的补体介导吞噬作用以及血浆sIGAM-1从第2天开始有不同程度的显著增加，并在恢复正常前持续约20天。相比之下，FcγRIII依赖性荧光和Ig介导的吞噬作用与对照值相比显著降低。这些结果表明，大面积烧伤后PMLs调理素受体表达和调理吞噬作用发生了显著变化，证明了PMLs的全身激活。此外，血浆sICAM-1的升高可能通过白细胞在皮肤和肺中的聚集以及通过内皮损伤的外渗来增强中性粒细胞激活的有害作用。
