In order to evaluate the immunological effects brought about by human Donor Bone Marrow Cell (DBMC) infusion accompanying organ transplantation, we have established in vitro cultures analogous to the transplant model. CML and MLC responses of allogeneic cells stimulated with irradiated donor spleen cells in presence of T cell depleted DBMC modulators were monitored. Compared to spleen cell modulator controls, DBMC inhibited both the MLC and CML responses in a dose dependent manner (n = 17). Irradiation of DBMC abrogated the modulatory effects (n=3). Furthermore, DBMC had to be added within the first two days of CML cultures for the down-regulation to occur. Separation of the DBMC from the responder-stimulator cells using transwell system abrogated the modulation of CML, thus suggesting the requirement of cell-cell contact for the modulatory effect (n = 6). The down-regulation of CML but not MLC response was antigen (donor) specific (n=5). The inhibitory activity by DBMC could not be overcome by the addition of up to 50U/ml rFL2 to the MLC and CML cultures (n=4). Both CD34 positive and negative DBMC inhibited MLC and CML of allogenic ceUs, thus suggesting that a cell population that developed from the CD34 progenitors in culture might be the responsible for the regulatory activity. These results clearly showed a regulatory role for DBMC in the donor specific cellular immune responses, thus indicating a rationale for DBMC to be used for induction of allograft acceptance in clinical transplantation.
|Original language||English (US)|
|State||Published - Dec 1 1996|
ASJC Scopus subject areas
- Molecular Biology