Abstract: Objective Human leukocyte antigen A (HLA A) silencing and tyrosine hydroxylase (TH) over-expressing human embryonic lung fibroblasts (HELFs) were grafted into the striatum of a rat model of Parkinson's disease (PD) to observe rotation behavior of the PD rats and inflammation in the brain. Methods The cultured HELFs were transduced with retrovirus carrying TH and lentivirus harboring HLA A siRNA and green fluorescent protein (GFP), and then grafted into the striatum of PD rats. The rotation behavior was measured, immunostaining for TH, OX42, OX6 and GFAP performed, and GFP was used to evaluate the survival of the grafted cells. HELFs and, HELFs and rat embryonic lung fibroblasts transduced with TH-containing retrovirus were grafted into the brain to serve as controls. Results The GFP fluorenscent cells were gradually reduced after transplantation, and relatively more cells were found in the HLA A silencing HELFs without significant amelioration of rotation behavior. The number of OX42-positive microglia was observed unchangeable, while OX6 cells were gradually increased. Activation of GFAP-positive astrocytes decreased with time, but significantly stronger than that in the contralateral side. Conclusions HLA A silencing could not promote amelioration of rotation symptom and intracerebral transplantation could induce activation of microglia and astrocytes.

Key words: Parkinson disease, HLA A, Tyrosine hydroxylase, xenotransplantation, RNAi