[Early development of the thymus-dependent cells attributable to recipient micro-environment in bone marrow chimera mice].
Irradiation bone marrow chimeras were established between AKR and C3H mice to analyze thymic influences on the early development of T-lineage cells. When AKR mice were used as recipients of bone marrow transplantation (AKR recipient chimeras), cell numbers recoverable from thymuses between 2 and 7 wks after reconstitution were consistently much greater (about 10 times) than those from chimeras where C3H mice were used as recipients (C3H recipient chimeras), regardless of the donor strains of bone marrow cells. Further, we found that proliferative responses to anti-CD3 mAb of thymocytes from C3H recipient chimeras were consistently lower than those of AKR recipient chimeras, even though these cells were expressing same levels of CD3 as those of the latter chimeras. By contrast, no differences were observed in increase of intracellular free Ca2+ levels induced by anti-CD3 mAb and in increase of IL-2 production induced by anti-CD3 mAb and PMA or PMA and A23187 among these chimeras. However, when these thymocytes were stimulated with immobilized anti-CD3 mAb, levels of IL-2 receptors expressed on the thymocytes from C3H recipient chimeras were less than those from AKR recipient chimeras. The present findings suggest that the cell number of thymus and the proliferative responsiveness to anti-CD3 mAb are determined by recipient micro-environment (e.g. thymic stroma) which supports and maintains the developing thymocytes.
Iwabuchi
C
C
Institute of Immunological Science, Hokkaido University, Sapporo, Japan.
D000818:Animals; D016026:Bone Marrow Transplantation; D002118:Calcium / Q000378:metabolism; D002452:Cell Count; D002454:Cell Differentiation; D002678:Chimera; D007376:Interleukin-2 / Q000096:biosynthesis; D007477:Ions; D051379:Mice; D009929:Organ Size; D013950:Thymus Gland / Q000166:cytology* / Q000378:metabolism
D007376:Interleukin-2; D007477:Ions; D002118:Calcium