Low Radiation Dose and Low Cell Dose Increase the Risk of Graft Rejection in a Canine Hematopoietic Stem Cell Transplantation Model.
Biol Blood Marrow Transplant
; 22(4): 637-643, 2016 Apr.
Article
em En
| MEDLINE
| ID: mdl-26802322
ABSTRACT
The canine hematopoietic stem cell transplantation (HSCT) model has become accepted in recent decades as a good preclinical model for the development of new transplantation strategies. Information on factors associated with outcome after allogeneic HSCT are a prerequisite for designing new risk-adapted transplantation protocols. Here we report a retrospective analysis aimed at identifying risk factors for allograft rejection in the canine HSCT model. A total of 75 dog leukocyte antigen-identical sibling HSCTs were performed since 2003 on 10 different protocols. Conditioning consisted of total body irradiation at 1.0 Gy (n = 20), 2.0 Gy (n = 40), or 4.5 Gy (n = 15). Bone marrow was infused either intravenously (n = 54) or intraosseously (n = 21). Cyclosporin A alone or different combinations of cyclosporine A, mycophenolate mofetil, and everolimus were used for immunosuppression. A median cell dose of 3.5 (range, 1.0 to 11.8) total nucleated cells (TNCs)/kg was infused. Cox analyses were used to assess the influence of age, weight, radiation dose, donor/recipient sex, type of immunosuppression, and cell dose (TNCs, CD34(+) cells) on allograft rejection. Initial engraftment occurred in all dogs. Forty-two dogs (56%) experienced graft rejection at median of 11 weeks (range, 6 to 56 weeks) after HSCT. Univariate analyses revealed radiation dose, type of immunosuppression, TNC dose, recipient weight, and recipient age as factors influencing long-term engraftment. In multivariate analysis, low radiation dose (P < .001) and low TNC cell count (P = .044) were identified as significant independent risk factors for graft rejection. Peripheral blood mononuclear cell chimerism ≥30% (P = .008) and granulocyte chimerism ≥70% (P = .023) at 4 weeks after HSCT were independent predictors of stable engraftment. In summary, these data indicate that even in low-dose total body irradiation-based regimens, the irradiation dose is important for engraftment. The level of blood chimerism at 4 weeks post-HSCT was predictive of long-term engraftment in the canine HSCT model.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Células da Medula Óssea
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Transplante de Medula Óssea
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Raios gama
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Rejeição de Enxerto
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Doença Enxerto-Hospedeiro
Tipo de estudo:
Etiology_studies
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Observational_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
Biol Blood Marrow Transplant
Assunto da revista:
HEMATOLOGIA
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TRANSPLANTE
Ano de publicação:
2016
Tipo de documento:
Article