Bujia J, Behrends U, Rotter N, Pitzke P, Wilmes E, Hammer C
Department of Otorhinolaryngology, Ludwig-Maximilians-University of Munich, Germany.
In Vitro Cell Dev Biol Anim. 1996 Feb;32(2):116-22. doi: 10.1007/BF02723043.
A major factor in cellular cytotoxicity is the interaction between LFA-1 on leukocytes and ICAM-1 on targets. Because several inflammatory cartilage diseases are characterized by the presence of leukocyte infiltrates, the expression of ICAM-1 on human cartilage, cultured chondrocytes, and transplanted cartilage was investigated using monoclonal antibodies. Frozen tissue sections, chondrocytes in suspension, as well as total cellular mRNA were prepared from human cartilage samples. ICAM-1 expression was studied with two different monoclonal antibodies directed against ICAM-1 by immunohistochemical APAAP-staining and additional flow cytometric analyses. The expression of ICAM-1-mRNA in cartilage tissue was analyzed using the northern blot hybridization technique. Furthermore, chondrocytes were treated in culture with interleukin-1 (IL-1) and gamma-interferon (gamma-IFN). ICAM-1 expression after culture was quantified using flow cytometric analysis. We could detect ICAM-1 mRNA in cartilage tissue, however, the immunostaining of tissue sections using monoclonal antibodies did not give clear positive reactions. Isolated chondrocytes showed strongly positive staining patterns in comparison with adequate negative controls as assessed by flow cytometry. A dose-dependent increase of the expression of ICAM-1 on chondrocytes was observed when stimulated with IL-1 and gamma-IFN. Finally, two of the three studied transplanted autologous cartilage samples with advanced resorption showed the presence of ICAM-1 molecules as assessed by immunohistochemistry. This expression of ICAM-1 suggests that the molecule plays a role in severe cartilage inflammatory processes, where tissue damage leads to the exposure of chondrocyte surfaces.
细胞毒性的一个主要因素是白细胞上的淋巴细胞功能相关抗原-1（LFA-1）与靶细胞上的细胞间黏附分子-1（ICAM-1）之间的相互作用。由于几种炎症性软骨疾病的特征是存在白细胞浸润，因此使用单克隆抗体研究了ICAM-1在人软骨、培养的软骨细胞和移植软骨上的表达。从人软骨样本中制备了冰冻组织切片、悬浮的软骨细胞以及总细胞mRNA。通过免疫组织化学碱性磷酸酶抗碱性磷酸酶（APAAP）染色和额外的流式细胞术分析，用两种针对ICAM-1的不同单克隆抗体研究了ICAM-1的表达。使用Northern印迹杂交技术分析软骨组织中ICAM-1-mRNA的表达。此外，在培养中用白细胞介素-1（IL-1）和γ-干扰素（γ-IFN）处理软骨细胞。培养后使用流式细胞术分析对ICAM-1表达进行定量。我们能够在软骨组织中检测到ICAM-1 mRNA，然而，使用单克隆抗体对组织切片进行免疫染色未得到明确的阳性反应。通过流式细胞术评估，与适当的阴性对照相比，分离的软骨细胞显示出强阳性染色模式。当用IL-1和γ-IFN刺激时，观察到软骨细胞上ICAM-1表达呈剂量依赖性增加。最后，通过免疫组织化学评估，三个研究的具有晚期吸收的自体移植软骨样本中有两个显示存在ICAM-1分子。ICAM-1的这种表达表明该分子在严重的软骨炎症过程中起作用，在该过程中组织损伤导致软骨细胞表面暴露。
