Induction of inflammatory gene expression in resident lamina propria cells following loss of the epithelial layer.

(A) Time scheme of the LEL model. Arrows indicate time points of tissue collection. Tissue samples were collected prior to culturing (TM t = 0 h), after washing (TM t = 2 h), as well during and after completion of epithelial cell release by EDTA treatment (LEL-M t = 3/4/5 h). As a control, tissue samples were collected from TM cultured for 5 h (TM t = 5 h). (B) LEL induces gene expression of IL1B, IL6, IL8, IL23A, TNFA, IFNG, and CCL2 in resident lamina propria cells. Transcript levels of cytokines/chemokines were determined by qRT-PCR in tissue samples collected as described in (A). Shown are the mean normalized transcript numbers ± SEM of at least 4 independent experiments. Gray bars represent transcript levels of TM (t = 0/2/5 h), black bars represent transcript levels of LEL-M (t = 3/4/5h). (C) EDTA treatment does not induce inflammatory cytokines in PBMC or LPMC. PBMC and LPMC, respectively, were exposed to 0.7 mM EDTA/HBSS or medium (RPMI/2% FCS) for 3 h. Subsequently, transcript levels of IL6, IL8, IL1B, and IL23A were determined by qRT-PCR (IL8 and IL23A not tested for LPMC). The results of two independent experiments are shown.