Signaling molecules involved in production and regulation of IL-1β by murine peritoneal macrophages in vitro on treatment with Concanavalin A

In the present study we report the activation of murine peritoneal macrophages in vitro on treatment with Concanavalin A (ConA). ConA (10 μg/ml) treatment of macrophages resulted in the transcription of IL-1β gene at 16 h and maximum production of IL-1β at 24 h. To investigate the signaling molecules involved in the production of IL-1β different pharmacological inhibitors were used. It was observed that genestein, wortmannin, H-7, TMB-8, PD98059, SB202190, and tyrophostin (AG490) down regulated the expression of IL-1β. These observations suggested the involvement of tyrosine kinase, PI3 kinase, protein kinase C, p42/44, p38, Ca++ and JAK2 signaling molecules in ConA induced production of IL-1β by macrophages. Maximum protein tyrosine kinase activity and expression of PI3K in macrophages was seen at 5 min, PKC activity and Ca++ release was found at 10 min after ConA treatment. Maximum expression of phospho-JAK2 at 2.5–5 min, phospho-p42/44 at 5–60 min, phospho-p38 at 15–30 min, phospho-IκB and phospho-Stat1 at 30–60 min and phospho-ELK1, c-Fos, phospho-Stat3 at 60 min of ConA treatment was observed. Pharmacological inhibitors were also used to check the cascade of activation of tyrosine kinase, PKC, PI3 kinase, p42/44, p38, JAK kinase and release of Ca++ from intracellular storage to sort out the signaling pathways involved in the release of IL-1β by macrophages on treatment with ConA in vitro.