EXPANSION OF CD3+CD8+ T LYMPHOCYTES FROM HUMAN CORD BLOOD

Abstract

Human cord blood (CB) has been used as a source of allogeneic hematopoietic stem cells forpatients of hematologic malignancies as it lowers the risk of graft versus host effect whiledelivering more graft versus tumor effect. T cell immunotherapy can be developed from CB,however, with the limited volume of cord blood collected and stored in CB banks, procedures toexpand T lymphocytes to a sufficient number are urgently required. Hence, we conduct the studywith an aim of establishing an optimal procedure for isolation and expansion of T lymphocytesfrom human cord blood that meets the requirement for cell therapy in cancer treatment. Three CBmononuclear cell (MNC) samples were collected by Ficoll and then the T cells were expanded byusing BINKIT kit from Biotherapy Institute of Japan. After 20 days of culture, the average numberof CD3+CD8+ T cells reached 890.3±150.3×106 cells, increased 403.8±240 times compared tothe number of these cells at seeding. The purity of cell population was not high, with the averagepercentage of CD3+CD8+ T cells (%) in the total cell was 49.4±10%, meanwhile this value of CD3+T cells was 74.5±14.4%. Of note, 2/3 samples had the decrease in the number of CD3+CD8+ Tcells at day 20 compared to day 13 of culture. In conclusion, we were successful in expansion ofCD3+CD8+ T cells from human cord bloods, with the adequate number for the cell therapy.However, the length of cell culture should be considered for each individual sample and theselection of CD3+CD8+ T cells at seeding should be carried out in order to increase the purity ofcell population after expansion.