[Cell-associated interleukin 1 production of alveolar macrophages from bleomycin-induced pulmonary fibrosis in rats].
In order to clarify the mechanisms of pulmonary fibrosis, we produced bleomycin (BLM)-induced pulmonary fibrosis in rats and examined the ability of alveolar macrophages (AM) to produce interleukin-1 (IL-1). BLM (0.9 mg) was administered once via the trachea to male Wistar rats weighing about 200 g. Bronchoalveolar lavage was performed at 1, 3, 6, 9 and 12 days after administration. AM were incubated for 24 hours, then extracellular IL-1 in the supernatants and cell-associated IL-1 of AM were measured by proliferation assay of mouse thymocytes. Cell-associated IL-1 activity was measured after fixation by paraformaldehyde (PFA). Extracellular IL-1 was detected in the culture media of AM at only day 1 after administration. On the other hand, cell-associated IL-1 was detected in AM fixed by PFA on days 1, 3, 6 and 9 after administration. AM from BLM-induced pulmonary fibrosis in rats were fixed by PFA and then were treated with anti-IL-1 alpha antibody or anti-IL-1 beta antibody. Cell-associated IL-1 activity was neutralized by treatment with anti-IL-1 alpha antibody and was not neutralized by treatment with anti-IL-1 beta antibody. Following this, the effect of cell-associated IL-1 on pulmonary fibroblasts was examined. This was estimated by the proliferation of pulmonary fibroblasts using incorporation of 3H-thymidine. When pulmonary fibroblasts were incubated with AM fixed by PFA from BLM-induced pulmonary fibrosis in rats, proliferation of pulmonary fibroblasts was inhibited.(ABSTRACT TRUNCATED AT 250 WORDS)
Asada
K
K
Third Department of Internal Medicine, School of Medicine, Tokushima University, Japan.
Ogushi
F
F
Tani
K
K
Yasuoka
S
S
Sone
S
S
Ogura
T
T
D000818:Animals; D001761:Bleomycin / Q000009:adverse effects*; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000502:physiology; D016676:Macrophages, Alveolar / Q000378:metabolism*; D008297:Male; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D007375:Interleukin-1; D001761:Bleomycin