The Alteration Of The Concentration Of Calcium In The Phagocytic Process Of Human Pigment Epithelium Cells

Hie human retinal pigment epitheliumis ( HRPE) cells has complicated structure and specific physiological function. The phagocytic faction of RPE is crucial for sustaining the vision. The failure of this phagocytosis will lead to the compiling of rod outer segments(ROS) and seriers eye degeneration. It has been proved that there had defective specific phagocytosis and normal nonsepecific phagocytosis in retinitis pigmentosa. For the mechanism of phagocytosis is unknown by now,to further the investigation of phagocytosis ,will invest hopeness to the prevention and therapy of this kind of disease. Though previous research has proved that the specific phagocytosis of RPEcells involves the interaction of ligment - receptor and transmembrane signal conducting system, the fruction of trasnsmembrane signal conducting system in the process of phagocytosis of HRPE cells is not very clear. Just for this reason ,we chose Ca2+ which is one molecule of the signal conducting pathway as the study object to question of RPE cell By medeling the phagocytic condition of normal HRPE cells and detecting the concentration of Ca2+ during the different stage in specific and nonspecific phagocytic character. To investigate the role of Ca2+ in the phagocytic process of human retinal pigment epithelium ( HRPE) cells.Material and method1. the source of eye ball;The eye balls are the normal eyes which are after cornea transplantation in department of Ophthalmolgy of the First Clinical College of China Medical University. The donor of the eyes is limited between 24 and 36 ages.2. Tissue culture of human retinal pigment epithelium cells:TO collect the HRPE cells by the trypsin.3. Isolation of ROS and pigment granules. Diluted ROS and pigment granules to final concentration of 10-7ml-1 with growth medium.4. Preparing the model of RPE phagocytosis. The cultured HRPE cells were incubated with 1 x l07ml-1 rod outer segments (ROS) or pigment granules at 37,then were rinsed the at different incubation time to terminate the phagocy-sia . The kinetics of phagocytosis was measured by double - fluorescent vital assay.5. Determining the intracellular free Ca2+ . By fluorescence microscope and CCD system, measuring the concentration of Ca + during different time of incubation.Results1. The initial binding and ingestion in specific phagocytosis of HRPE cells are earlier than in nonsepecific phagocytosis. In specific phagocytosis of HRPE cells . the binding of ROS happened at 15 min of incubation, but the binding of pigment granules by HRPE cells happened at 1.5h.2. The specific phagocytosis:The concentration of Ca2+ began to increase at 15 min and sustained during the specific phagocytosis periods.3. The nonspecific phagocytosis: The concentration of Ca2+ did not chang during the nonspecific phagocytosis periods.Conclusion1. The initial binding and ingestion in specific phagocytosis of HRPE cells are earlier than in nonsepecific phagocytosis.2. Ca2+ is very important for sustaining the ingestion process in specific phagocytosis of HRPE cells, but has no direct relationship with nonspecific phagocytosis, we can conclude that it has different mechanism between the specific phagocytosis and the nonspecific phagocytosis .