Autostimulatory adherent cells in the spleen of aging mice: characterization in the syngeneic host-versus-graft reaction.
Enlargement of the popliteal lymph node (PLN) of 6-week-old mice were elicited by the footpad injection of spleen cells of sex-matched, syngeneic, older mice, but not of 6-week-old mice, in a fashion of host-vs.-graft reaction. Effective stimulating cells in the inoculum seem to be Ia-bearing adherent cells. On the other hand, neither B and T cells nor immunoglobulin-secreting cells were effective for host T cell stimulation. Among nonlymphocytic adherent cells, only those attached to plastic dishes after a 24 h-incubation, enriched in macrophages, showed the stimulatory activity for the young recipients, while cells which had adhered once but detached and became non-adherent during a 24 h-incubation or a crude non-macrophage fraction did not induce the PLN response. Thus, the age-related antigenic change may occur on macrophages but not on dendritic cells. The effective cells should be alive, heat-killed cells being impotent to elicite the response. Such spleen adherent cells of aged mice were found to be also stimulative for age-matched recipients, when they are older than 3 months. Autostimulation by macrophages might be responsible, at least in part, for the age-related change of immune functions.
D000375:Aging; D000818:Animals; D002448:Cell Adhesion; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006789:Host vs Graft Reaction; D007136:Immunoglobulins / Q000276:immunology; D008264:Macrophages / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011817:Rabbits / Q000276:immunology; D012756:Sheep / Q000276:immunology; D013154:Spleen / Q000166:cytology* / Q000637:transplantation; D014185:Transplantation, Isogeneic
D000949:Histocompatibility Antigens Class II; D007136:Immunoglobulins