OBJECTIVEThe study was designed to explore the influence of transfected bone marrow mononuclear cells (BMMNC) transplantation on the hematopoietic cells activity and the recipient mice hematopoietic reconstitution.

METHODSThe exogenous mFasL-cDNA gene was transferred to Balb/C mouse BMMNC by liposomes. Then the transferred BMMNC was co-cultured with BMMNC from BAC mouse (H-2d x b, male) at a ratio of 0.625 to 1 for 6 days. In the experimental group (the 3rd group), 1 x 10(7) (0.5 ml) mixed viable cells were injected into whole bodily irradiated ((60)Co-r) mice (6 to 8 week old female Balb/C) via the tail vein. The following grafted mice were simultaneously used in the study, the mice transplanted with 0.5 ml of culture medium, the mice transplanted with the mixture of untransferred Balb/C mouse BMMNC and BAC mouse BMMNC, the mice transplanted with the mixture of transferred Balb/C mouse BMMNC and BAC mouse BMMNC and the mice transplanted with Balb/C mouse BMMNC. The hematopoietic reconstitution, the origin of bone marrow cells responsible for the reconstitution, the graft versus host disease (GVHD), the survival rate for the recipient mice were observed after bone marrow transplantation (BMT).

RESULTSThe counts of leukocytes and platelets in recipient blood of group four on +10 d and +20 d after BMT were higher than those in group three and group two (P < 0.01), but on +30 d after BMT the counts of leukocytes and platelets in recipient blood of group two, group three and group four were at their normal levels. The Y chromosome from donor mice was discovered in BMMNC of recipient mice having survived for over two months after BMT in group two and group three. The survival rate of the recipient mice two mouths after BMT in all groups were 0% for group one, 30% for group two, 80% for group three, and 100% for group four, respectively. The total survival rate of recipient mice in the experimental group was obviously higher than that of group two (P < 0.01). Grade II to III GVHD signs were found on the histology from dead mice after BMT in group three and group two, and the mice having survived for over two months in the group two. Grade I GVHD signs were found on histology from 7 out of 8 mice which survived for over two months after BMT in group three.

CONCLUSIONSThe transplantation of mixed cells into recipient mice made the recipient mice achieve hematopoietic reconstitution from donor BMMNC.