Dados do Trabalho

Título

VALIDATION OF THE USE OF HYDROXYETHYL STARCH (VOLUVEN® 6%) TO REMOVE DIMETHYL SULFOXIDE FROM HEMATOPOIETIC STEM CELLS

Introdução

During the process of cryopreservation of hematopoietic stem cells
(CTH), the dimelthyl sulfoxide (DMSO) is responsible for ensuring a better
cell viability and a satisfactory engraftment but, at the time of the graft infusion, it can cause serious adverse events, particularly in young children, in patients with renal dysfunction, cardiac insufficiency, hemodynamic instability, or
when the dose of DMSO is equal to or greater than 1g/DMSO/Kg of body weight. An effective way to avoid serious reactions is to remove the DMSO using a washing solution composed by 40% dextran and 4% albumin. We have used this protocol, initially developed by the New York Blood Bank to remove DMSO and improve engraftment of unrelated umbilical cord blood units, since 2011. However, in October, 2023 we were informed with a short notice about the discontinuity of the production of dextran40 (Laboratório de Insumos Farmacêuticos Ltda - LIFE).

Objetivo

To describe the validation of the DMSO removal of hematopoietic stem cells in a Cellular Processing Laboratory using solution hydroxyethyl starch (HAES)-Voluven® 6% and albumin 4%, comparing the results of removal using dextran40 solution with 4% albumin.

Método

We used 22 bags from 7 patients: 16 from leukapheresis of deceased patients and 6 collected as donor leukocyte infusions (DLI) but unused due to the development of graft-versus-host disease (GVHD). All families gave authorization for the cells to be discarded or used in research. Two similar bags were chosen from the same patient, stem cell source, volume and cellularity for parallel thawing in a 37oC water bath and then adding one of the solutions (Dextran vs Voluven) in each bag at a 1:1 ratio. A sample was removed for nucleated cell count (CNT) and cell viability. The bags were centrifuged at 2,000 rpm or 805 g, 20 minutes, 4°C, with a brake. Using a manual extractor, the supernatant was transferred to another bag and the buffy coats were measured using a 50 ml syringe, resuspended with the same respective thawing solutions and counted again, as well as the supernatant to indicate a possible cell loss.

Resultados

Nucleated cell recoveries – total cells (TNC), lymphocyte and monocytes using Voluven® were 88% (75 -100), 100%(83-100) and Dextran 83% (77-92), 96% (78-100). There was no cell loss in the supernatant, median TNC 0.01x109 (0-0.39) and 0.06x109 (0-0.49), respectively.

Conclusão

The DMSO removal using HAES Voluven® 6% solution and albumin 4% was similar to Dextran40 and, therefore, validated in our service.