Pathogen reduction/inactivation of products for the treatment of bleeding disorders:what are the processes and what should we say to patients?

Patients with blood disorders (including leukaemia, platelet function disorders and coagulation factor deficiencies) or acute bleeding receive blood-derived products, such as red blood cells, platelet concentrates and plasma-derived products. Although the risk of pathogen contamination of blood products has fallen considerably over the past three decades, contamination is still a topic of concern. In order to counsel patients and obtain informed consent before transfusion, physicians are required to keep up to date with current knowledge on residual risk of pathogen transmission and methods of pathogen removal/inactivation. Here, we describe pathogens relevant to transfusion of blood products and discuss contemporary pathogen removal/inactivation procedures, as well as the potential risks associated with these products: the risk of contamination by infectious agents varies according to blood product/region, and there is a fine line between adequate inactivation and functional impairment of the product. The cost implications of implementing pathogen inactivation technology are also considered

Nitroxide-Mediated Controlled Free-Radical Emulsion and Miniemulsion Polymerizations of Styrene

International audienc

Recombination Pattern of the Tcr Gamma-Locus in Human Peripheral T-Cell Lymphomas

The recombination events of the gamma and beta T-cell receptor (TCR) loci were analysed in a series of 39 peripheral T-cell lymphomas (PTCLs) in association with the expression of TCR chains. In TCR alpha beta PTCLs, 22/23 cases showed a gamma-gene rearrangement while only 18/23 showed a concomitant beta-gene rearrangement. The germline configuration of the beta locus was found in angioimmunoblastic lymphadenopathy and lymphoepithelioid lymphomas. Three gamma delta PTCLs rearranged both gamma and beta genes. TCR silent PTCLs showed three different patterns of gamma- and beta-gene rearrangements. Three cases were in germline configuration for both loci; five cases had a rearranged gamma and a germline beta locus; and five cases had the two loci rearranged. Regarding the variable genes in the gamma-rearranged alleles, members of the V gamma I subgroup were the most frequently presented (39/50), followed by V gamma II, V gamma III, and V gamma IV (9/50, 1/50, and 1/50, respectively). Joining segment usage was as follows: J1 or J2 (32/50), JP1 or JP2 (17/50), and JP (1/50). Taken together, these data demonstrate that the gamma locus is more frequently rearranged whatever the TCR expression. The gamma-locus analysis provides a better diagnostic yield than the beta locus in the study of PTCL clonality

Recombination Pattern of the Tcr Gamma-Locus in Human Peripheral T-Cell Lymphomas

The recombination events of the gamma and beta T-cell receptor (TCR) loci were analysed in a series of 39 peripheral T-cell lymphomas (PTCLs) in association with the expression of TCR chains. In TCR alpha beta PTCLs, 22/23 cases showed a gamma-gene rearrangement while only 18/23 showed a concomitant beta-gene rearrangement. The germline configuration of the beta locus was found in angioimmunoblastic lymphadenopathy and lymphoepithelioid lymphomas. Three gamma delta PTCLs rearranged both gamma and beta genes. TCR silent PTCLs showed three different patterns of gamma- and beta-gene rearrangements. Three cases were in germline configuration for both loci; five cases had a rearranged gamma and a germline beta locus; and five cases had the two loci rearranged. Regarding the variable genes in the gamma-rearranged alleles, members of the V gamma I subgroup were the most frequently presented (39/50), followed by V gamma II, V gamma III, and V gamma IV (9/50, 1/50, and 1/50, respectively). Joining segment usage was as follows: J1 or J2 (32/50), JP1 or JP2 (17/50), and JP (1/50). Taken together, these data demonstrate that the gamma locus is more frequently rearranged whatever the TCR expression. The gamma-locus analysis provides a better diagnostic yield than the beta locus in the study of PTCL clonality