Objective To investigate the effects of gamma;-interferon (IFN-gamma; on the expression of costimulatory molecules B7-1 (CD80) and B7-2 (CD86) and Fas/FasL in human retina. Methods Nine human eyes were obtained from the eye-bank of Zhongshan Ophthalmic Center. Six eyes were used for making retinal wholemounts, and 12 retinal wholemounts from each eye were put into the 24-hole culture board which had 2ml DMEM/F12 culture medium in each hole. The wholemounts were divided into 3 groups whose concentration of IFN-gamma; was 0, 200, and 1000 U/ml respectively. After cultured in 37℃ culture box (95%O 2，5%CO 2) for 24 hours, the expressions of B7-1 (CD80), B7-2 (CD86), and Fas/FasL on these retinal wholemounts were detected by immunohistochemical method. The retinal wholemounts from 3 healthy people were detected by immunohistochemical method as the control. Results Expression of FasL but not B7-1, B7-2 or Fas was found in the control group, while the expression of B7-1, B7-2 and Fas and increased expression of FasL were found after cultured with IFN-gamma;. Conclusion IFN-gamma; may be involved in the occurrence of ocular immune response and induction of apoptosis via the stimulation of expression of costimulatory molecules and Fas/FasL, which plays an important role in the activation of T lymphocytes. (Chin J Ocul Fundus Dis, 2006, 22: 117-119)
Objective To investigate the correlation of expression of Fas/Fas ligand (FasL) and apoptosis in retinoblastoma (RB)． Methods The expression and distribution of Fas/FasL were detected by using immunohistochemical staining in 32 cases of RB． Light microsc opy (32 cases), electron microscopy (4 cases) and TdT mediated biotin-d UTP nick-end labeling (TUNEL) (12 cases) were used to study apoptosis in RB． Results Apoptotic RB cells mostly located at RB regress area． Chromatin margination and apoptotic bodies were found in RB． TUNEL posi tive labeling cells especially located in tumor regress area． Positive immunola beling for Fas and FasL was found in all RB specimens． There was a highly signi ficant and positive correlation between the expression of Fas/FasL and apoptotic indices (AI) (Plt;0.01 or 0.001)． Conclusion The results suggest that apoptotic cell death is prevalent in RB and it may be one type of the most dominant cell death． Fas system may play an important role in oncogenesis and progression of RB, and the up-regulation of Fas system expression might induce RB cell apoptosis． (Chin J Ocul Fundus Dis, 2001,17:21-23)