6533b85bfe1ef96bd12ba9db

RESEARCH PRODUCT

TRANSPLANTATION AND IN VITRO ANALYSIS OF SOYBEAN-AGGLUTININ SEPARATED MOUSE SPLEEN CELLS

subject

description

In human bone marrow allotransplantation, an in vitro method using soybean agglutinin(SBA) for enrichment of stem cells and depletion of mature T cells in the graft has been described (Reisner et al.;Lancet 2:1320,1980).To define the quality of the method,mouse spleen cells (C3H, C57/B6,BALB/c)containing about 30% of mature T cells were separated by SBA.The composition and functional capacity of the cell fraction known to contain the stem cells were characterized in vitro after each of two SBA-separation steps.In addition, the ability of the cell fraction to reconstitute successfully allogeneic irradiated (900R) mice was investigated. Only the two step SBA-separation procedure yielded satisfying results: In comparison to the unseparated spleen cells,a three-fold increase in stem cells(CFU-c) and a 10-fold decrease of T cells( 3% Thy1.2-pos.) was observed. Analysis by lectin and allogeneic stimulation showed significant diminuation of the cell function:The response (ratio) to PHA,Con A,and in the MLR dropped from 147,184,and 30 to 16,23,and 1.5. Transplantation of 107 two-step separated spleen cells in allogeneic irradiated recipients (C57/B6 in BALB/c; C3H or BALB/c in C57/B6;C57/B6 in C3H) resulted in complete reconstitution in 18% to 58% of the grafted animals. In contrast,all the animals of two control groups (with and without transplantation of 107 unseparated spleen cells) died either of GvHD or of wasting.- The results demonstrate that the SBA-separation procedure cannot completely eliminate the risk of GvHD in cell suspensions with an high amount of mature T lymphocytes.