Z. Prakapas et al., ANALYSIS OF EARLY RECONSTITUTION EVENTS IN THE SCID MOUSE THYMUS FOLLOWING RAT BONE-MARROW CELL TRANSPLANTATION, Immunology letters, 37(1), 1993, pp. 63-71
In this work, we provide comprehensive evidence that sublethally irrad
iated Thy-1.2 SCID mice can be used as a model system for thymus homin
g and reconstitution after intravenous transfer of rat bone marrow cel
ls. Full short-term SCID mouse thymus reconstitutions were obtained us
ing a plastic nonadherent low-density rat bone marrow cell subset. Cel
l counts and flow cytometric analysis showed that at 3 weeks post-tran
sfer, the SCID mouse thymus contained up to 41 x 10(6) Thy-1.1high rat
lymphoid cells comprising the expected percentages and distribution o
f CD2+, CD5+, CD3+, alphabeta TCR+ and CD4+ CD8+ cells. As seen on cry
ostat sections, bone marrow-derived MHC class II+ accessory cells had
already developed by 2 weeks post-transfer, preceding the thymocyte ex
pansion apparent at 3 weeks. Thus, analysis of the early events of SCI
D thymus reconstitution by rat bone marrow cells shows that they close
ly resemble those described in congenic animals and points out the tem
porally distinct development of dendritic cells and thymocytes. The SC
ID mouse-rat chimera model system represents a new in vivo tool for ma
nipulating rat T-cell differentiation from bone marrow-resident precur
sor cells and in addition supports our previous xenogeneic reconstitut
ion studies performed in organ culture.