Detection of IL-1 alpha and IL-1 beta gene expression by in situ hybridization. Tissue localization of IL-1 mRNA in the normal C57BL/6 mouse.
IL-1 is a cytokine with a wide variety of effects on cells involved in inflammatory and immune responses, hemopoiesis, and bone formation. Many cell types have been shown to produce IL-1 in vitro; however, very little is known about the source and role of IL-1 in vivo. By using in situ hybridization, we examined the tissue distribution of cells containing IL-1 mRNA in normal C57BL/6 mice. The results show that many organs contain IL-1 mRNA-positive cells, but the highest frequency was found in lymphoid organs. The distribution and localization of these cells suggest that many of the IL-1 mRNA-producing cells are tissue macrophages. Organs exposed to environmental Ag and microbial products (lymph nodes, liver, intestine, lung, and uterus) had high frequencies of IL-1 mRNA-producing cells, suggesting that IL-1 is produced in local inflammatory or immune responses in vivo. The production of IL-1 mRNA in the thymus and in the bone marrow suggests that IL-1 is available to play physiologic roles in T cell differentiation and in hemopoiesis.
Takács
L
L
Laboratory of Molecular Immunoregulation, National Cancer Institute, Frederick, MD 21701.
Kovacs
E J
EJ
Smith
M R
MR
Young
H A
HA
Durum
S K
SK
D000818:Animals; D001853:Bone Marrow / Q000032:analysis; D001842:Bone and Bones / Q000032:analysis; D004817:Epidermis / Q000032:analysis; D005260:Female; D005796:Genes; D006412:Hematopoietic Stem Cells / Q000032:analysis; D007375:Interleukin-1 / Q000235:genetics* / Q000302:isolation & purification; D008099:Liver / Q000032:analysis; D008198:Lymph Nodes / Q000032:analysis; D008221:Lymphoid Tissue / Q000032:analysis*; D008264:Macrophages / Q000032:analysis; D051379:Mice; D008810:Mice, Inbred C57BL; D009693:Nucleic Acid Hybridization; D010581:Peyer's Patches / Q000032:analysis; D012333:RNA, Messenger / Q000302:isolation & purification; D013154:Spleen / Q000032:analysis; D013950:Thymus Gland / Q000032:analysis; D014599:Uterus / Q000032:analysis
D007375:Interleukin-1; D012333:RNA, Messenger