L’infection primaire au VZV et la réactivation du VZV latent sont fréquemment observées à la suite d’une GMO ou d’une GSCO, ce qui cause de sérieuses complications chez le patient. Pour prévenir ces infections, une prophylaxie antivirale est administrée systématiquement chez tous les greffés de MO ou de SCO, alors qu’il n’existe aucun consensus sur la durée optimale d’une telle prophylaxie. Pour résoudre ce problème, notre objectif est de développer et valider une méthode ELISpot-VZV-IFN- qui permettra de suivre la reconstitution de l’immunité à médiation cellulaire anti-VZV chez les receveurs de GMO ou de GSCO et ainsi déterminer le moment opportun pour réduire ou interrompe la prophylaxie chez les receveurs de greffes de CSH. Dans un premier temps, des valeurs-seuil de la réponse à médiation cellulaire anti-VZV chez la population pédiatrique saine ont dû être générées. À la lumière de nos résultats, un enfant avec un résultat ELISpot-VZV-IFN- > 190.0 SFU/106 PBMC devrait être protégé contre une possible infection à VZV. Pour valider cette étude, une étude prospective de la reconstitution immunitaire anti-VZV a été effectuée chez 9 enfants greffés de MO ou de SCO. Nos résultats préliminaires ont montré qu’il n’y avait eu aucune reconstitution significative de l’immunité à médiation cellulaire anti-VZV dans les 18 premiers mois post-transplantation chez 8 de ces 9 enfants. Les résultats de ces expériences vont fournir d’importantes informations quant à la reconstitution de l’immunité anti-VZV à la suite d’une GMO ou d’une GSCO et pourraient permettre l’amélioration des soins apportés aux receveurs de GMO ou de GSCO. / Primary infection with VZV and reactivation of latent VZV are commonly observed following BMT and UCBT, leading to serious complications in patients. As a result, antiviral prophylaxis is systematically administered to BMT and UCBT recipients, yet there is no consensus that defines its optimal duration. To resolve this problem, our objective was to develop and validate a VZV-IFN--ELISpot with which reconstitution of VZV immunity can be followed in BMT and UCBT recipients, providing clinicians a practical tool to gauge the need for and adjust antiviral prophylaxis in individual HSCT recipients. First of all, threshold values for anti-VZV immunity in healthy pediatric subjects were generated. Based on our results, a child exhibiting > 190.0 VZV-specific SFU /106 PBMC should be protected against a possible VZV infection. To validate these results, a prospective study on the recovery of VZV-specific T cell immunity was performed on 9 children following BMT or UCBT. Preliminary results demonstrated that there was no significant recovery of VZV-specific T cell immunity in the first 18 months post-transplantation in 8 of 9 cases. Results of these experiments will yield important new information regarding reconstitution of anti-VZV immunity following BMT and UCBT and could lead to improvements in clinical management of BMT and UCBT recipients.

Le busulfan (Bu) est un composé clé de la phase de conditionnement chez les enfants subissant une transplantation des cellules souches hématopoïétiques (TCSH). Les différences inter-individuelles de la pharmacocinétique (PK) du Bu pourraient affecter son efficacité et sa toxicité. Le Bu est principalement métabolisé par la glutathion-S-transférase (GST). Nous avons étudié la relation des génotypes GSTA1, GSTM1 et GSTP1 avec la PK de la première dose de Bu et la relation avec les résultats de la TCSH chez 69 enfants recevant un régime de conditionnement myéloablatif. Le génotype GSTM1 nul a corrélé avec une exposition élevée du Bu et une faible clairance (CL) chez les patients âgés de 4 ans (p ≤ 0,04). Dans le respect du rôle fonctionnel suggéré d’haplotype GSTA1 *A2, il a été associé à des niveaux plus faibles de médicaments et des niveaux élevés de CL (p ≤ 0,03). L’effet Gène-dose a également été observé (p = ≤ 0,007). L’haplotype de GSTA1 était associé avec les résultats de la TCSH. Les porteurs de deux copies d’haplotype *A2 avaient une meilleure survie sans événement (p = 0,03). En revanche, les individus homozygotes pour haplotypes * B et *B1 ont un risque plus élevé d’atteindre la maladie veino-occlusive (MVO) (p = 0,009). Les individus porteurs de GSTM1 nul âgés de 4 ans possèdent un risque plus fréquent d’avoir la maladie du greffon contre l'hôte (GvHD) (p = 0,03). En conclusion, nous avons montré que les variantes génétiques de GST influencent la PK du BU et les résultats de la TCSH chez les enfants. Pour l'ajustement de la posologie, un modèle avec l'inclusion des facteurs génétiques et non génétiques devrait être évalué et validé dans une étude prospective. / Busulfan (Bu) is a key compound of conditioning regimen in children undergoing hematopoietic stem cell transplantation (HSCT). Inter-individual differences in Bu pharmacokinetics might affect Bu efficacy and toxicity. Since Bu is mainly metabolized by glutathione S-transferase (GST), we investigated the relationship between GSTA1, GSTM1 and GSTP1 genotypes with first-dose Bu pharmacokinetics (PK), and relationship with HSCT outcomes in 69 children receiving myeloablative conditioning regimen. GSTM1 null genotype correlated with higher Bu exposure and lower clearance in patients older than 4 years (p≤0.04). In accordance with the suggested functional role GSTA1*A2 haplotype was associated with lower drug levels and higher drug clearance (p≤0.03). Gene-dosage effect was also observed (p=≤0.007). GSTA1 haplotypes were associated with HSCT outcomes Patients with two copies of haplotype *A2 had better event free survival (p=0.03). In contrast, homozygous individuals for haplotypes *B and *B1 had higher occurrence of veno-occlusive disease (p=0.009). GSTM1 null individuals older than 4 years had more frequently graft versus host disease (p=0.03). In conclusion, we showed that GST gene variants influence Bu PK and outcomes of HSCT in children. A model for the dosage adjustment with the inclusion of genetic and non-genetic factors should be evaluated in a future prospective validation cohort.

Das Auftreten manifester transplantationsassoziierter thrombotischer Mikroangiopathie sowie das Auftreten leichterer, zumeist subklinischer mikroangiopathischer Veränderungen wurde in einem Kollektiv von Patienten untersucht, die zur Behandlung einer steroidrefraktären oder abhängigen akuten oder chronischen GvHD nach allogener Stammzelltransplantation eine Therapie mit extrakorporalen Photopheresen erhielten. Subklinische mikroangiopathische Schädigung wurde durch ein auf den Messwerten von Fragmentozyten, Thrombozyten sowie der LDH-Aktivität beruhendes Bewertungsschema festgestellt. Das Auftreten von ausgeprägten mikroangiopathischen Veränderungen (Schweregrad 2) ging mit einem erniedrigten Gesamtüberleben einher. Die Reduktion der Steroiddosis und die Verringerung der GvHD-Manifestationen wurden als Parameter für die Wirksamkeit der ECP analysiert. Ihre Effektivität wurde bestätigt. Trotz der nachgewiesenen Effektivität der ECP in der Kontrolle der GvHD zeigte sich eine Tendenz zur Zunahme mikroangiopathischer Veränderungen unter Therapie mit ECP, in Einzelfällen mit schwerwiegenden klinischen Konsequenzen.

Treatment results and clinical characteristics in adult acute lymphoblastic leukaemia (ALL) were evaluated regarding three issues: a new treatment with cytarabine up-front, stem cell transplantation and a comparison between adult and paediatric treatment protocols. All studies were conducted on a national basis. Furthermore, activity of imatinib was investigated by in vitro cytotoxicity assay. The national protocol was evaluated in 153 adult ALL patients. A high complete remission rate, 86%, was achieved with 29% overall survival at 3-years. Favourable outcome was identified in patients < 40 years with precursor B phenotype and continuous complete remission was higher for precursor B compared to T-ALL. Stem cell transplantation was evaluated in 187 patients. No differences in outcome between allogeneic and autologous transplantation were found, with the exception of Philadelphia-positive ALL, in which allogeneic transplantation was preferable. Limited chronic graft-versus-host disease (compared to none) resulted in superior disease free survival. The paediatric NOPHO-92 and the Adult protocols were evaluated for 243 ALL-patients. Superior remission rate and survival were achieved for 10-18 year-olds treated according to the Paediatric protocol compared to both 15-25 and 25-40 year-olds treated according to the Adult protocol. Treatment protocol was a significant prognostic factor for patients aged 15-20 years. Fluorometric Microculture Cytotoxicity Assey was used to analyze 15 tumour cell samples from ALL patients. High concordance was determined between in vitro sensitivity to imatinib and presence of BCR-ABL. Daunorubicin, prednisolone and cytarabine had the greatest benefit from a combination with imatinib. The national adult treatment protocol’s results were consistent with international trials regarding precursor B ALL but may be under performing for T-ALL. Adolescents may benefit from treatment according to the Paediatric protocol. No difference in outcome between allogeneic and autologous stem cell transplantation was determined except for Philadelphia-positive patients, despite the indication of a graft-versus-leukaemia effect.

Survival of patients with poor prognosis or relapsed haematopoietic malignancies can be markedly improved by allogeneic haematopoietic stem cell transplantation (HSCT). HSCT reconstitutes the immune and haematopoietic systems after myeloablative conditioning and inhibits the recurrence of the malignancy by a graft-versus-leukaemia (GVL) response mediated by donor T cells. However, significant post-transplant complications such as graft-versus-host disease (GVHD) continue to plague the event-free survival of this curative procedure. GVHD is facilitated by donor T cells that recognise histocompatibility antigens on host antigen presenting cells (APC), such as dendritic cells (DC). Current treatment options for GVHD are focused on these T cells. However, these treatments result in an increased incidence of infection, graft rejection and relapse. A novel means of immunosuppression in GVHD is the use of multi-potent, mesenchymal stromal cells (MSC). MSC are non-immunogenic cells that actively suppress T cell function in vitro, and can resolve steroid-refractory GVHD in the clinic. Despite their use in the clinic, there is a paucity of pre-clinical data. Our aim was to investigate the in vivo efficacy of MSC to control GVHD while maintaining the beneficial GVL effect, and to begin to understand the mechanism by which MSC exert their immunosuppressive effects. We isolated and characterised MSC from murine bone/bone marrow and demonstrated that they suppressed T cell proliferation in vitro, even at low ratios of 1 MSC per 100 T cells. This was true of both donor-derived MSC, and MSC derived from unrelated donors (third party). Importantly, we observed that MSC significantly reduced T cell production of the pro-inflammatory cytokines TNFα and IFNγ in culture supernatants and that IFNγ plays a key role in the ability of MSC to suppress T cell proliferation. In vivo, we examined the effects of donor-derived MSC on GVHD severity and onset in two myeloablative murine models of HSCT. A major histocompatibility complex (MHC)-mismatched donor-recipient pair combination was used as a proof–of-principle model [UBI-GFP/BL6 (H-2b)àBALB/c (H-2d)], and an MHC-matched, minor histocompatibility antigen (miHA) mismatched donor-recipient pair combination was used to mimic MHC-matched sibling transplantation [UBI-GFP/BL6 (H-2b)àBALB.B (H-2b)]. We examined a number of variables related to MSC infusion including timing, dose and route of injection. We found that early post transplant infusion of MSC by the intraperitoneal injection was most effective at delaying death from GVHD, compared to pre-transplant infusion or intravenous injection. Furthermore, we found that the dose of MSC was critical, as infusion of too few MSC was ineffective and infusion of too many MSC exacerbated the development of GVHD. Taken together, these results suggest that timing, dose and route of injection are all important factors to be considered to ensure successful therapeutic outcome. To investigate the in vivo mechanism of action, we conducted timed sacrifice experiments in the MHC-mismatched model to determine if MSC altered cytokine secretion and cellular effectors, such as DC, known to play a key role in GVHD. Despite the fact that MSC given post-HSCT enter an environment full of activated DC and IFNγ levels, by day 3 and 6 post infusion, these activated DC and IFNγ levels are decreased compared to controls or mice infused with MSC pre-transplant (p<0.05). This confirmed our in vitro data that IFNγ played an important role in MSC-mediated immunosuppression. In addition, when we removed a major source of IFNγ production in vivo by administering the T cell depleting antibody KT3 to mice with or without MSC, we found that although T cell depletion prolonged survival, MSC were unable to further enhance this effect. This was also true when MSC were used in combination with the conventional immunosuppressant cyclosporine. Finally, we examined whether the infusion of MSC would compromise the GVL effect. We found that whilst MSC could delay the onset of GVHD, in our model they did not alter the anti-tumour effects of the donor T cells. Overall, we have shown that MSC can delay but not prevent death from GVHD when administered at an appropriate time and dose and that IFNγ is required for MSC-mediated immunosuppression in our model. These data suggest that patients undergoing HSCT should be monitored for IFNγ, and administered MSC when high levels are reached. Whilst MSC may be a promising therapy for patients with severe GVHD, we highlight that further investigation is warranted before MSC are accepted for widespread use in the clinic. The risks and benefits for transplant recipients should be carefully considered before utilising MSC to treat or prevent GVHD.

Survival of patients with poor prognosis or relapsed haematopoietic malignancies can be markedly improved by allogeneic haematopoietic stem cell transplantation (HSCT). HSCT reconstitutes the immune and haematopoietic systems after myeloablative conditioning and inhibits the recurrence of the malignancy by a graft-versus-leukaemia (GVL) response mediated by donor T cells. However, significant post-transplant complications such as graft-versus-host disease (GVHD) continue to plague the event-free survival of this curative procedure. GVHD is facilitated by donor T cells that recognise histocompatibility antigens on host antigen presenting cells (APC), such as dendritic cells (DC). Current treatment options for GVHD are focused on these T cells. However, these treatments result in an increased incidence of infection, graft rejection and relapse. A novel means of immunosuppression in GVHD is the use of multi-potent, mesenchymal stromal cells (MSC). MSC are non-immunogenic cells that actively suppress T cell function in vitro, and can resolve steroid-refractory GVHD in the clinic. Despite their use in the clinic, there is a paucity of pre-clinical data. Our aim was to investigate the in vivo efficacy of MSC to control GVHD while maintaining the beneficial GVL effect, and to begin to understand the mechanism by which MSC exert their immunosuppressive effects. We isolated and characterised MSC from murine bone/bone marrow and demonstrated that they suppressed T cell proliferation in vitro, even at low ratios of 1 MSC per 100 T cells. This was true of both donor-derived MSC, and MSC derived from unrelated donors (third party). Importantly, we observed that MSC significantly reduced T cell production of the pro-inflammatory cytokines TNFα and IFNγ in culture supernatants and that IFNγ plays a key role in the ability of MSC to suppress T cell proliferation. In vivo, we examined the effects of donor-derived MSC on GVHD severity and onset in two myeloablative murine models of HSCT. A major histocompatibility complex (MHC)-mismatched donor-recipient pair combination was used as a proof–of-principle model [UBI-GFP/BL6 (H-2b)àBALB/c (H-2d)], and an MHC-matched, minor histocompatibility antigen (miHA) mismatched donor-recipient pair combination was used to mimic MHC-matched sibling transplantation [UBI-GFP/BL6 (H-2b)àBALB.B (H-2b)]. We examined a number of variables related to MSC infusion including timing, dose and route of injection. We found that early post transplant infusion of MSC by the intraperitoneal injection was most effective at delaying death from GVHD, compared to pre-transplant infusion or intravenous injection. Furthermore, we found that the dose of MSC was critical, as infusion of too few MSC was ineffective and infusion of too many MSC exacerbated the development of GVHD. Taken together, these results suggest that timing, dose and route of injection are all important factors to be considered to ensure successful therapeutic outcome. To investigate the in vivo mechanism of action, we conducted timed sacrifice experiments in the MHC-mismatched model to determine if MSC altered cytokine secretion and cellular effectors, such as DC, known to play a key role in GVHD. Despite the fact that MSC given post-HSCT enter an environment full of activated DC and IFNγ levels, by day 3 and 6 post infusion, these activated DC and IFNγ levels are decreased compared to controls or mice infused with MSC pre-transplant (p<0.05). This confirmed our in vitro data that IFNγ played an important role in MSC-mediated immunosuppression. In addition, when we removed a major source of IFNγ production in vivo by administering the T cell depleting antibody KT3 to mice with or without MSC, we found that although T cell depletion prolonged survival, MSC were unable to further enhance this effect. This was also true when MSC were used in combination with the conventional immunosuppressant cyclosporine. Finally, we examined whether the infusion of MSC would compromise the GVL effect. We found that whilst MSC could delay the onset of GVHD, in our model they did not alter the anti-tumour effects of the donor T cells. Overall, we have shown that MSC can delay but not prevent death from GVHD when administered at an appropriate time and dose and that IFNγ is required for MSC-mediated immunosuppression in our model. These data suggest that patients undergoing HSCT should be monitored for IFNγ, and administered MSC when high levels are reached. Whilst MSC may be a promising therapy for patients with severe GVHD, we highlight that further investigation is warranted before MSC are accepted for widespread use in the clinic. The risks and benefits for transplant recipients should be carefully considered before utilising MSC to treat or prevent GVHD.

Survival of patients with poor prognosis or relapsed haematopoietic malignancies can be markedly improved by allogeneic haematopoietic stem cell transplantation (HSCT). HSCT reconstitutes the immune and haematopoietic systems after myeloablative conditioning and inhibits the recurrence of the malignancy by a graft-versus-leukaemia (GVL) response mediated by donor T cells. However, significant post-transplant complications such as graft-versus-host disease (GVHD) continue to plague the event-free survival of this curative procedure. GVHD is facilitated by donor T cells that recognise histocompatibility antigens on host antigen presenting cells (APC), such as dendritic cells (DC). Current treatment options for GVHD are focused on these T cells. However, these treatments result in an increased incidence of infection, graft rejection and relapse. A novel means of immunosuppression in GVHD is the use of multi-potent, mesenchymal stromal cells (MSC). MSC are non-immunogenic cells that actively suppress T cell function in vitro, and can resolve steroid-refractory GVHD in the clinic. Despite their use in the clinic, there is a paucity of pre-clinical data. Our aim was to investigate the in vivo efficacy of MSC to control GVHD while maintaining the beneficial GVL effect, and to begin to understand the mechanism by which MSC exert their immunosuppressive effects. We isolated and characterised MSC from murine bone/bone marrow and demonstrated that they suppressed T cell proliferation in vitro, even at low ratios of 1 MSC per 100 T cells. This was true of both donor-derived MSC, and MSC derived from unrelated donors (third party). Importantly, we observed that MSC significantly reduced T cell production of the pro-inflammatory cytokines TNFα and IFNγ in culture supernatants and that IFNγ plays a key role in the ability of MSC to suppress T cell proliferation. In vivo, we examined the effects of donor-derived MSC on GVHD severity and onset in two myeloablative murine models of HSCT. A major histocompatibility complex (MHC)-mismatched donor-recipient pair combination was used as a proof–of-principle model [UBI-GFP/BL6 (H-2b)àBALB/c (H-2d)], and an MHC-matched, minor histocompatibility antigen (miHA) mismatched donor-recipient pair combination was used to mimic MHC-matched sibling transplantation [UBI-GFP/BL6 (H-2b)àBALB.B (H-2b)]. We examined a number of variables related to MSC infusion including timing, dose and route of injection. We found that early post transplant infusion of MSC by the intraperitoneal injection was most effective at delaying death from GVHD, compared to pre-transplant infusion or intravenous injection. Furthermore, we found that the dose of MSC was critical, as infusion of too few MSC was ineffective and infusion of too many MSC exacerbated the development of GVHD. Taken together, these results suggest that timing, dose and route of injection are all important factors to be considered to ensure successful therapeutic outcome. To investigate the in vivo mechanism of action, we conducted timed sacrifice experiments in the MHC-mismatched model to determine if MSC altered cytokine secretion and cellular effectors, such as DC, known to play a key role in GVHD. Despite the fact that MSC given post-HSCT enter an environment full of activated DC and IFNγ levels, by day 3 and 6 post infusion, these activated DC and IFNγ levels are decreased compared to controls or mice infused with MSC pre-transplant (p<0.05). This confirmed our in vitro data that IFNγ played an important role in MSC-mediated immunosuppression. In addition, when we removed a major source of IFNγ production in vivo by administering the T cell depleting antibody KT3 to mice with or without MSC, we found that although T cell depletion prolonged survival, MSC were unable to further enhance this effect. This was also true when MSC were used in combination with the conventional immunosuppressant cyclosporine. Finally, we examined whether the infusion of MSC would compromise the GVL effect. We found that whilst MSC could delay the onset of GVHD, in our model they did not alter the anti-tumour effects of the donor T cells. Overall, we have shown that MSC can delay but not prevent death from GVHD when administered at an appropriate time and dose and that IFNγ is required for MSC-mediated immunosuppression in our model. These data suggest that patients undergoing HSCT should be monitored for IFNγ, and administered MSC when high levels are reached. Whilst MSC may be a promising therapy for patients with severe GVHD, we highlight that further investigation is warranted before MSC are accepted for widespread use in the clinic. The risks and benefits for transplant recipients should be carefully considered before utilising MSC to treat or prevent GVHD.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.

Introdução: Células-troco mesenquimais (CTM) vêm mostrando seus benefícios na doença do enxerto-versus-hospedeiro (DECH), observada no transplante de células tronco hematopoéticas (TCTH), existem três questões em aberto: (1) Expansão de CTM em meio de cultura suplementado com soro fetal bovino (SFB), pelo o risco de xenorreação; (2) Otimização de condições de cultura para a obtenção, em tempo hábil, de um numero que permita de 4 a 6 infusões de 2x106cells/kg do receptor; (3) Obter células do doador de medula óssea, evitando assim a utilização de um terceiro doador. Objetivos: Este estudo foi desenhado para comparar o lisado de plaquetas (LP) e o SFB na expansão de CTM, a densidade de plaqueamento das células e os dias entre cada passagem, e para investigar se as células nucleadas totais obtidas da bolsa e filtro do TCTH, podem ser utilizadas para expansão de CTM para utilização clínica. Métodos: Células residuais foram removidas do filtro e da bolsa utilizados para o TCTH, plaqueadas e depois da primeira passagem foram cultivadas em diferentes concentrações com SFB ou LP e observado o número de dias que levaram para chegar a 80% de confluência. Em seguida, as culturas com as mesmas densidades de plaqueamento foram suplementadas com LP ou SFB e depois de sete dias contou-se o número de células para analisar o quanto elas cresceram nesse período. Resultados: A proliferação de CTM, na presença de LP e SFB foi em média 11,88 e 2,5 vezes, respectivamente, num período de 7 dias. A concentração mais elevada de células usando LP demorou menos tempo para atingir a confluência, em comparação com os três inferiores. Este estudo sugere que o LP é a melhor escolha como suplemento para expandir CTM, e permite a proliferação de um número suficiente de CTM de doadores para uso clínico. / Introduction: Mesenchymal stromal cells (MSC) have shown their benefits in graft-versus-host disease (GVHD), with three unsettled matters:(1) MSCs expansion in medium with Fetal Calf Serum (FCS) and its risk of xenoreaction; (2) The number of cells indicated for therapy is 2x106cells/Kg with the need to optimize expansion, number and time wise; and (3) the utilization of third party donors. Aims: This study was designed to compare the platelet lysate (LP) and FCS on the expansion of MSC, the optimal cell plating density and days between each pass, and to investigate if donor total nucleated cells (TNC) obtained from the washouts of hematopoietic stem cell transplantation (HSCT) explants can be expanded to be used at clinical grade. Methods: TNC were removed, plated and after the first passage were cultivated in different concentrations with FCS or PL and the number of days reach 80% of confluence was observed. Next, cultures with the same plating density were fed either with PL or FCS and after seven days counted to analyze how much they have grown in that period. Results: The proliferation of mesenchymal stromal cells in the presence of PL and SFB was averaged 11.88 and 2.5 times, respectively, in a period of 7 days. The highest concentration of plating cells using PL, took less time to reach confluence as compared with the three lower ones. This study suggests that the PL is the best choice as a supplement to expand MSC, and allows the proliferation of a sufficient number of donors MSC at P2 for clinical use.

Introdução: O Transplante de Célula Tronco Hematopoiética (TCTH) é um tratamento potencialmente curativo para muitas desordens hematológicas. A disparidade HLA entre doador e receptor é um fator crítico para os resultados do TCTH. No entanto novas evidencias tem demonstrado que outros fatores como a fonte de célula tronco, o tipo de condicionamento e fatores relacionados aos doadores, entre eles o sexo, a idade e o status sorológico para Citomegalovirus (CMV) podem influenciar os desfechos do procedimento. Objetivo: Avaliar as características dos doadores de medula óssea e seu impacto nos desfechos do TCTH em um centro do Sul do Brasil. Métodos: Foram avaliadas retrospectivamente as características dos doadores como sexo, idade, presença de exposição previa ao CMV, incompatibilidade ABO e suas relações com a ocorrência de doença do enxerto contra hospedeiro (DECH) aguda e crônica, a mortalidade relacionada ao transplante (do inglês tumor related mortality – TRM) sobrevida livre de doença (SLD) e sobrevida Global (SG) em todos os pacientes submetidos a TCTH alogênico em um único centro durante o período de 1994 a 2012. Resultados: 347 pacientes foram incluídos na análise. O TCTH aparentado foi significativamente mais freqüente que o não aparentado (81.2 x 18.7), a mediana de idade foi de 34 (1-61) para os receptores e 33 (1-65) para os doadores. Na analise multivariada a presença de DECH agudo (33% vs 47%) p=0,04 e ter doadores mais idosos (>40 anos) foram associados a uma redução de SG em 5 anos (41% vs 52%) p=0,038. Ter um doador acima de 40 anos aumenta significativamente a incidência de DECH aguda (52% vs 65,8%) p=0,03 e crônica (60% vs 43%) p=0,015. O sexo do doador, presença de CMV e incompatibilidade ABO não tiveram influencia nos desfechos. Conclusão: Em um centro único avaliado receber um transplante de CTH de doadores acima de 40 anos aumenta a incidência de DECH aguda e crônica e influencia negativamente na SG. / Background: Hematopoietic Stem cell Transplantation (HSCT) is a curative treatment for many patients with hematological disorders. Donor – recipient genetic disparity, especially involving the HLA systems is a critical factor for HSCT outcome There are increasing evidences, however that other issues as source of stem cell, conditioning regimen, donor gender, age and CMV infection can affect HSCT outcomes. Objective: To study the influence of donor’s characteristics on the HSCT outcomes in a south Brazilian population subjected to allogeneic SCT in a single center. Methods: We retrospectively evaluated donor characteristics such as gender, age, CMV serologic status and ABO compatibility and its relation to the occurrence of acute and chronic graft versus host disease (GVHD), disease free survival (DFS) and overall survival (OS) in all patients submitted to related and unrelated allogeneic HSCT, performed between 1994 and 2012. Results: Overall 347 consecutives HSCT were included in this analysis. Related HSCT was significantly more frequent than unrelated (81.2% x 18.7%); donor and recipient median age were 34 (1- 61) and 33 (1-65), respectively. In the multivariate analyses, presence acute GVHD (33%vs 47%)p=0.04 ,with relative risk and donors older than 40 years old was associated with lower probability of OS in 5 years (41% vs 52%) p=0,038 and higher rate of acute (65.8%vs 52%) p=0.03 and chronic GVHD (43% vs 60%) p=0,015. Donor’s sex, CMV status, ABO incompatibility have not influenced 5-years survival. Conclusions: In a single center population of patients submitted to related and unrelated HSCT in southern Brazil donor older then 40 years of age is a factor negatively influencing HSCT outcome.