Release of interleukin-1 (IL-1) and IL-1-like factors from rabbit macrophages with silica.
Oil-elicited rabbit macrophages stimulated by endotoxin were found to release increased amounts of interleukin 1 (IL-1) when incubated with silica. The assays used to determine the amount of IL-1 released were uptake of thymidine by mouse thymocytes, fever in rabbits, and neutrophilia in rats. All three assays showed that endotoxin-stimulated macrophages released five to 10 times more IL-1 when incubated with silica. Most of the IL-1 had a molecular weight (MW) of about 14,000 with a smaller amount at a MW of approximately 35,000. All of the neutrophilia-producing activity had an isoelectric point (pl) near 7. Thymocyte proliferation was promoted about equally by activities near pH 5 and 7. Fever was found not only at these two isoelectric points but also at a pl above 8 which had neither of the other two activities.
D000818:Animals; D004731:Endotoxins / Q000494:pharmacology; D007375:Interleukin-1 / Q000378:metabolism* / Q000494:pharmacology; D007525:Isoelectric Focusing; D008213:Lymphocyte Activation / Q000187:drug effects; D008222:Lymphokines / Q000378:metabolism*; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D008970:Molecular Weight; D011817:Rabbits; D051381:Rats; D012822:Silicon Dioxide / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000187:drug effects
D004731:Endotoxins; D007375:Interleukin-1; D008222:Lymphokines; D012822:Silicon Dioxide