Mesenchymal stem cell infusion on skin wound healing of dexamethasone-immunosuppressed wistar rats/Infusao de celulas tronco mesenquimais sobre a cicatrizacao de feridas cutaneas em ratos wistar imunossuprimidos com dexametasona

To evaluate the therapeutic contribution of MSC intravenous infusion to surgical wound healing in dexamethasone immunosuppressed rats, thirty-five rats were randomly divided into 2 groups: in the Control Group (CG), five rats received normal saline as 0.2ml subcutaneous (SC) injections every 24 hours, for 30 consecutive days and, in the Dexamethasone Group (DG), 30 rats were given 0.2mL subcutaneous dexamethasone (0.1mg [kg.sup.-1]) every 24 hours, for 30 consecutive days. After 30 days, all rats underwent surgery to create an experimental skin wound. The 30 animals of the DG group were divided into two equal groups, which received different treatments: the dexamethasone group (DG) received a single application of 0.5ml normal saline, via the intravenous route (IV), 48 hours after wound creation; and the Mesenchymal Stem Cells Dexamethasone group (MSCDG) received MSC transplantation at a concentration of 9x[10.sup.6] cells in a single IV application, 48 hours after wound creation. The surgical wounds of CG rats closed on average 14.75 days after creation and DG rats had wounds closed within 22 days; whereas, the surgical wounds of MSCDG rats were closed in 14 days. MSC infusion in dexamethasone-immunosuppressed patients contributed positively to epithelial healing in less time. Key words: tissue repair, cell therapy, immunomodulation. O presente trabalho teve como objetivo avaliar a contribuicao terapeutica da infusao de celulas tronco mesenquimais na cicatrizacao cutanea de ratos imunossuprimidos com dexametasona. Utilizaram-se 35 animais, distribuidos em dois grupos: Grupo Controle (GC), formado por cinco animais que receberam aplicacoes de 0,2ml de solucao fisiologica a cada 24 horas por via subcutanea (SC) e Grupo Dexametasona (GD), formado por trinta animais que receberam aplicacoes a cada 24 horas de 0,2mL de dexametasona (0,1mg [kg.sup.-1]), por via SC, todos durante 30 dias consecutivos. Apos os 30 dias, todos os animais foram submetidos a procedimento cirurgico para a criacao de ferida cutanea experimental. Os 30 animais do GD foram subdivididos em dois grupos equivalentes, diferenciados quanto ao tratamento: Grupo Dexametasona (GD), que receberam uma unica aplicacao de 0,5ml de solucao fisiologica, por via IV, 48 horas apos a criacao da ferida; e Grupo Dexametasona Celulas Tronco Mesenquimais (GDCTM), que receberam o transplante de CTM, na concentracao de 9 x [10.sup.6] celulas, em aplicacao unica, por via IV 48 horas apos a criacao da ferida cir