Chemotherapy or targeted therapy are usually used to treat hematological pathologies. Despite of medical improvement, some of these pathologies present drug resistances, or high risk of relapse. Hematopoietic stem cell (HSC) transplantation remain the gold standard of consolidation, to maintain a durable response. In this situation, allograft with hematopoietic stem cells donor aims at producing Graft-versus-Tumor effect, by producing a new immune system, reproducing anti-tumoral immunity.

However, all hemopathies do not have the same sensibility. Nowadays, mechanisms underlying this phenomenon remain poorly understood.

Indeed, few data precisely document the expression of immunological checkpoints and other biomarkers in the context of allogeneic HSC transplantation, particularly their impact on post-transplant outcome.

Chemotherapy or targeted therapy are usually used to treat hematological pathologies. Despite of medical improvement, some of these pathologies present drug resistances, or high risk of relapse. Hematopoietic stem cell (HSC) transplantation remain the gold standard of consolidation, to maintain a durable response. In this situation, allograft with hematopoietic stem cells donor aims at producing Graft-versus-Tumor effect, by producing a new immune system, reproducing anti-tumoral immunity.

However, all hemopathies do not have the same sensibility. Nowadays, mechanisms underlying this phenomenon remain poorly understood.

Indeed, few data precisely document the expression of immunological checkpoints and other biomarkers in the context of allogeneic HSC transplantation, particularly their impact on post-transplant outcome. Therefore, we want to systematically study the expression profile of different biomarkers during allogeneic transplantation, in order to establish a correlation between these expression patterns and post-transplant outcome. Ultimately, this research will enable to (i) have tools to predict the post-transplant response and (ii) define whether a targeted therapy could be beneficial or be contraindicated for adequate patient management.

Patients will be selected for the study once they meet all the inclusion criteria. The study will be proposed to them during the pre-allogeneic consultation as part of their usual care. This study does not modify the treatment or the usual management of patients according to the current practice of pre- and post-transplant management. Clinically, it consists of building up a relevant biological collection.

Inclusion Criteria:

• Adult patient, over 18 years of age, suffering from a malignant hemopathy (without exception),
• Patient for whom an allogeneic hematopoietic stem cell transplant from a related or unrelated donor is indicated,
• Signed informed consent,
• Patient covered by a social security scheme.

Exclusion Criteria:

• Allogeneic hematopoietic stem cell transplantation from cord blood or haplo-identical transplant,
• Allogeneic transplant with post-transplant cyclophosphamide treatment,
• Allograft with sequential conditioning.