OBJECTTo investigate the therapeutic effect of microencapsulated porcine retinal pigmented epithelial cells (RPE-M) transplantation on rat model of Parkinson's disease (PD).

METHODSPrimary porcine RPE cells were harvested by enzyme digestion and expanded in culture medium. Determine the levels of dopamine (DA) and homovanillic acid (HVA) by high performance liquid chromatography electrochemical (HPLC) assay, and the levels of brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF) were detected by ELISA. Alginate-polylysine-alginate (APA) microencapsulated cells were produced by using a high voltage electrostatic system. PD rat model was established by unilateral injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle (MFB). After that, the RPE-M was transplanted into the corpus striatum of PD rat, and then the rotation test scores were recorded and biochemical changes of the corpus striatum were tested.

RESULTSThe levels of DA, HVA, BDNF and GDNF secreted by RPE were stable in the RPE culture supernatant and were not changed by the microencapsulation. Eighty-three percent rats developed PD by unilateral lesion of 6-OHDA in the MFB. The RPE-M transplantation had therapeutic effect on 33% PD rats.

CONCLUSIONPorcine RPE cells grow actively in vitro and could secrete DA, HVA, BDNF, and GDNF constantly, which does not be affected by the passage culture and the APA miroencapsulation. RPE-M transplantation of may be a curative therapy for PD.