RESUMO
Defective apoptosis might be involved in the pathogenesis of multiple sclerosis (MS). We evaluated apoptosis-related molecules in MS patients before and after autologous haematopoietic stem cell transplantation (AHSCT) using BCNU, Etoposide, AraC and Melphalan (BEAM) or cyclophosphamide (CY)-based conditioning regimens. Patients were followed for clinical and immunological parameters for 2 years after AHSCT. At baseline, MS patients had decreased proapoptotic BAD, BAX and FASL and increased A1 gene expression when compared with healthy counterparts. In the BEAM group, BAK, BIK, BIMEL , FAS, FASL, A1, BCL2, BCLXL , CFLIPL and CIAP2 genes were up-regulated after AHSCT. With the exception of BIK, BIMEL and A1, all genes reached levels similar to controls at day + 720 post-transplantation. Furthermore, in these patients, we observed increased CD8+ Fas+ T cell frequencies after AHSCT when compared to baseline. In the CY group, we observed increased BAX, BCLW, CFLIPL and CIAP1 and decreased BIK and BID gene expressions after transplantation. At day + 720 post-AHSCT, the expression of BAX, FAS, FASL, BCL2, BCLXL and CIAP1 was similar to that of controls. Protein analyses showed increased Bcl-2 expression before transplantation. At 1 year post-AHSCT, expression of Bak, Bim, Bcl-2, Bcl-xL and cFlip-L was decreased when compared to baseline values. In summary, our findings suggest that normalization of apoptosis-related molecules is associated with the early therapeutic effects of AHSCT in MS patients. These mechanisms may be involved in the re-establishment of immune tolerance during the first 2 years post-transplantation.
Assuntos
Apoptose/genética , Proteína 5 Relacionada à Autofagia/genética , Esclerose Múltipla/genética , Adulto , Linfócitos T CD8-Positivos/efeitos dos fármacos , Ciclofosfamida/uso terapêutico , Feminino , Expressão Gênica/genética , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Condicionamento Pré-Transplante/métodos , Transplante Autólogo/métodos , Adulto JovemRESUMO
Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by T cell-mediated destruction of pancreatic ß cells, resulting in insulin deficiency and hyperglycaemia. Recent studies have described that apoptosis impairment during central and peripheral tolerance is involved in T1D pathogenesis. In this study, the apoptosis-related gene expression in T1D patients was evaluated before and after treatment with high-dose immunosuppression followed by autologous haematopoietic stem cell transplantation (HDI-AHSCT). We also correlated gene expression results with clinical response to HDI-AHSCT. We observed a decreased expression of bad, bax and fasL pro-apoptotic genes and an increased expression of a1, bcl-x(L) and cIAP-2 anti-apoptotic genes in patients' peripheral blood mononuclear cells (PBMCs) compared to controls. After HDI-AHSCT, we found an up-regulation of fas and fasL and a down-regulation of anti-apoptotic bcl-x(L) genes expression in post-HDI-AHSCT periods compared to pre-transplantation. Additionally, the levels of bad, bax, bok, fasL, bcl-x(L) and cIAP-1 genes expression were found similar to controls 2 years after HDI-AHSCT. Furthermore, over-expression of pro-apoptotic noxa at 540 days post-HDI-AHSCT correlated positively with insulin-free patients and conversely with glutamic acid decarboxylase autoantibodies (GAD65) autoantibody levels. Taken together, the results suggest that apoptosis-related genes deregulation in patients' PBMCs might be involved in breakdown of immune tolerance and consequently contribute to T1D pathogenesis. Furthermore, HDI-AHSCT modulated the expression of some apoptotic genes towards the levels similar to controls. Possibly, the expression of these apoptotic molecules could be applied as biomarkers of clinical remission of T1D patients treated with HDI-AHSCT therapy.