STUDY OF THE IMPACT OF THE PRO-INFLAMMATORY RESPONSE ON THE DIFFERENTIATION OF HUMAN DOPAMINERGIC PRECURSORS

XIANMIN ZENG; MARIA ISABEL FARIAS; CARINA FERRARI; VICTORIA GRADASCHI; FERNANDO J PITOSSI; CORINA GARCIA; SHIRLEY D.WENKER

Buenos Aires- CABA

Congreso; Reunión conjunta de socciedades de Biociencias; 2017

Reunión conjunta de socciedades de Biociencias

Parkinson ´s Disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic (DA) neurons of the substantia nigra pars compacta. Transplantation of dopamine-producing cells into the striatum has already shown its effectiveness in animal models and clinical trials. Here, we aimed to study the host primary response related to the graft of human DA precursors (DA14) in vivo and the impact of proinflammatory factors on the viability and differentiation process of DA14 cells in vitro. A protocol of DA differentiation from human neural stem cells was standardized and characterized by immunofluorescence (IF) for the following markers: bIIITubulin (neuronal cells), GFAP (astroglial cells), Foxa2 (DA precursors) and Tyrosine hydroxylase (TH) (DA neurons). We were able to obtain cultures at two stages: DA14 (Foxa2: 71,5%; TH: 5,2%) and final stage, called DA28 (bIIITubulin: 59,4%; TH: 17,4%; GFAP: 3,9%). For in vivo assay, DA14 were transplanted into the striatum of adult immunosuppressed rats and host-primary response was analysed by IF. Preliminary results showed host-MHCII and GFAP positive cells within the graft after 7 days of surgery. In order to study the effect of microglial activation on DA14 maturation in vitro, BV2 microglial cells were activated with LPS. Then, DA14 cells were exposed to conditioned media (CM) from basal and activated BV2 cells for 4 days and IF for TH positive cells were made at DA28 stage. Results from TH cell counting revealed that exposure of DA14 to CM from activated microglia decreases the number of DA neurons at final stage (%TH: CMbasal: 100 vs CMactivated: 59,6±4,2 P