Por:
Guillermo Andrés Orjuela Falla
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Fecha:
2009
CD34+ cell dose in the transplanted product is still considered a measure of the engraftment potential in haemopoietic stem cell transplantation (HSCT). CD34+ selected products are characterised by their high purity and depleted T-cells. These characteristics have made them traditionally suitable to decrease the incidence of graft versus host disease, particularly in haploidentical HSCT.
The CliniMACS is a state of the art cell sorting system based on magnetic particles conjugated to CD34 antibodies. This study retrospectively evaluated the CliniMACS system performance in terms of CD34+ purity and cell recovery, and T-cell depletion in the selected product. The results were compared against target values fixed by the processing centre, as well as against published data. Factors affecting the CD34+ cell recovery were also investigated and a pilot study was carried out to assess the effect of cryopreservation on the viability of the selected products. In total, 151 procedures were analysed.
The mean recovery and purity were 64.82 + 16.19 and 88.0 + 11.0% respectively. The mean T-cell depletion was 4.7021 + 0.5129 logs. Only purity was slightly below the specification (90%), with the lowest values obtained from peripheral blood (PB) collections. Factors affecting the recoveries were the overall age of the product (p=0.001), overnight storage (p=0.002), and the use of a particular tubing set with the instrument (p=0.002).
The mean CD34+ viability was not significantly different to the value before cryopreservation (p=0.068). Results from this study were comparable with published data of the CliniMACS system performance. Local investigations regarding the purity of PB products should be performed. For the first time, using a magnetic separation method, factors affecting CD34+ recovery were identified. The significance of the effect of product age and overnight storage on cell recovery, provide a rationale for further prospective studies
Fuente:
Biblioteca Virtual Banco de la República
Formatos de contenido:
Tesis
