Browsing by Subject "leukafereesivalmiste"

Adoptive cell therapy utilizes the patient's own immunological system in the treatment of cancer. T cells expressing the chimeric antigen receptor (CAR) are produced from the patient's own T-cells. The CAR gene is introduced into the T cells by a gene transfer vector, which results in the T cells expressing the CAR molecule that recognizes the antigen on the surface of the cancer cell. When CAR-T cells are returned to the body, they recognize the cancer cell with the CAR molecule and destroy it. CAR-T cell therapy has shown promising results in the treatment of malignant hematological cancers. The white blood cells used as starting material for CAR-T cells are collected from the patient using a specially designed leukapheresis device. The collected leukapheresis product is transported to the CAR-T cell manufacturing site as soon as possible, either fresh or frozen. The aim of this stability study of leukapheresis products was to determine the effect of storage time and temperature on the quality of fresh cell products regarding cell number, viability and composition. In addition, the goal was to determine the optimal storage temperature and the shelf life of leukapheresis product to ensure high quality cell starting material for CAR-T cell production. The study was performed by dividing the leukapheresis products into two cell bags immediately after collection, one stored at +15–25 °C and the other at +2–8 °C for five days. The leukapheresis products were examined at five different time points (0, 25, 49, 73 and 121 h) for white blood cell count, viability, apoptosis and white blood cell composition. The microbiological purity of the cell products was examined after leukapheresis. The leukocyte composition was stable, viability and cell yield over 80 % for at least 72 hours at +2–8 °C storage temperature. Although small proportions of cells were apoptotic after the 48 hours of storage +2–8 °C, the leukapheresis products contained more than 80 % viable leukocytes after 72 hours and over 70 % after 120 hours. Leukapheresis products remained stable for 48 hours at +15–25 °C, after which their leukocyte composition changed, leukocyte viabilities and yields decreased. The viabilities of the leucocytes were above 90 % for 48 hours at +15–25 °C, but at the 73 h time point, only half of the cells were viable. The optimum storage temperature for leukapheresis products was +2–8 °C, at which white blood cells remained in good quality for 72 hours. These results can be used to set quality requirements for the cell source material of CAR-T cell product and to plan the transport from the collection site of the leukapheresis to the CAR-T cell production site.