title: Freezing of rat lymphocytes. V. The effect of suppressor cells in phytohaemagglutinin-stimulated spleen cell cultures before and after freeze-thawing.
abstract: Spleen lymphocyte proliferation, as measured by 3H-thymidine incorporation induced by phytohaemagglutinin (PHA), was increased after freeze-thawing with 10% dimethyl sulphoxide. Depletion or intoxication of macrophages in fresh spleen cell preparations also increased lymphocyte proliferation in response to PHA. On the other hand, freezing of macrophage-depleted spleen cell suspensions lowered 3H-thymidine uptake of stimulated cultures. At concntrations above 3%, macrophages added to cultures of fresh purified lymphocytes showed a dose-dependent inhibitory effect on the PHA response, and fresh macrophages were more inhibitory than frozen-thawed macrophages. Purified lymphocytes mixed with 10% macrophages showed a higher response after freeze-thawing. It is concluded that macrophages suppress the lymphoproliferative response to PHA in rat spleen cell cultures, and that these macrophages are more sensitive than lymphocytes to the present freeze-thaw process.
mesh_terms: D000818:Animals; D000941:Antigens; D002351:Carrageenan / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D005260:Female; D005615:Freezing; D007958:Leukocyte Count; D008198:Lymph Nodes / Q000166:cytology; D008213:Lymphocyte Activation / Q000187:drug effects; D008212:Lymphocyte Depletion; D008264:Macrophages / Q000276:immunology; D008297:Male; D009000:Monocytes / Q000276:immunology; D010835:Phytohemagglutinins / Q000494:pharmacology*; D051381:Rats; D013154:Spleen / Q000166:cytology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000941:Antigens; D010835:Phytohemagglutinins; D002351:Carrageenan