Naturally occurring immunosuppressive agents. I. The presence in normal pig liver of a factor possessing immunosuppressive properties with respect to pig lymphoid cells in vitro.
Saline cell-free extracts of normal pig liver, but not normal pig spleen, contain a noncytotoxic factor (or factors) capable of suppressing the blastogenic response of pig lymphocytes to stimulation with a number of plant mitogens: phytohemagglutinin, pokeweed, and concanavalin A. This reaction is generally considered to be a reflection of the capacity of the cell to participate in an immune reaction. Normal pig serum does not display inhibitory activity. The liver extract must be in contact with the lymphocytes for at least the final 48 hr of the 72-hr culture period in order to suppress the blastogenic response. Whether this active constituent in normal pig liver extract is an immunosuppressive agent in vivo remains to be determined.
D000818:Animals; D001773:Blood Cells / Q000276:immunology; D002474:Cell-Free System; D002478:Cells, Cultured; D003208:Concanavalin A; D007166:Immunosuppressive Agents / Q000032:analysis*; D007668:Kidney / Q000276:immunology; D037102:Lectins; D008099:Liver / Q000276:immunology*; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*; D013154:Spleen / Q000276:immunology; D013552:Swine; D014020:Tissue Extracts
D007166:Immunosuppressive Agents; D037102:Lectins; D014020:Tissue Extracts; D003208:Concanavalin A