Immediate-early, Transient Induction of the Interleukin-1.BETA. Gene in Mouse Spleen Macrophages by Ionizing Radiation.

Abstract

In murine spleen cells, x ray irradiation induces the expression of the IL-1 beta gene at multiple phases of the peak time. We analyzed the immediate-early phase of IL-1 beta mRNA accumulation. To determine the lineage of cells that showed the immediate response to irradiation, normal spleen cells were analyzed by Northern blotting and in situ hybridization after separation by magnetic antibodies against specific cell-surface antigens. Although most of the spleen macrophages continuously expressed a low level of IL-1 beta mRNA, a portion of the macrophage population transiently accumulated large amounts of IL-1 beta message immediately after irradiation. A macrophage-like leukemia cell line that resembles these inducible macrophages was identified. A similar immediate-early and transient increase in the IL-1 beta mRNA level occurred when cultured spleen cells were irradiated with a low dose (3 Gy) of x rays. In contrast, the x ray-inducible expression of the IL-1 beta gene was immediate and continuous, not transient, in spleen cells from whole-body irradiated mice. Results of the run-on transcription assay and the determination of the decrease in the message using cultured spleen and macrophage-like leukemia cells indicated that x ray irradiation appears to activate the transcription of the IL-1 beta gene and partially stabilize the message. The results show that the x ray-induced immediate-early accumulation of IL-1 beta mRNA is regulated at both the transcriptional and post-transcriptional levels in an as yet unidentified population of spleen macrophages.

Impact of irradiation and immunosuppressive agents on immune system homeostasis in rhesus macaques

“…Multiple studies have reported that ionizing radiation leads to increased expression of proinflammatory cytokines [92][93][94] as well as inducing inflammasome pathway activation in immune cell populations [95]. Our analysis revealed several changes consistent with a heightened inflammatory milieu.…”

Radiotherapy and Immunity – A Mini Review

“…Increased expression of proinflammatory cytokines, including TNF-a and IL-1b following radiation has been reported by some authors (Hallahan et al,1989;Ishihara et al, 1995;Nemoto et al, 1995). These observations suggest a potential role for radiation in signaling 'danger' and, perhaps, in the activation of antigen presenting cells (McBride et al, 2004).…”

Response of Crypt Paneth Cells in the Small Intestine following Total-Body γ-Irradiation

“…The mechanism of this delayed effect is not clear. It has been recently shown that activation of the IL-1~pathway due to direct effects of irradiation can occur at transcriptional, translational, and post-translational levels and involves a stress-sensitive CASP-I signaling platform (31,(33)(34). The activation of these events requires minutes to hours (31,(33)(34).…”

“…It has been recently shown that activation of the IL-1~pathway due to direct effects of irradiation can occur at transcriptional, translational, and post-translational levels and involves a stress-sensitive CASP-I signaling platform (31,(33)(34). The activation of these events requires minutes to hours (31,(33)(34). We did not find a significant difference of the ileal IL-I~levels between sham and irradiated mice at the 2 nd day of observations despite increased IL-I~levels in blood plasma (not shown).…”