Expression of surface receptors in resident lamina propria cells following loss of the epithelial layer.

<p>(<b>A</b>) LEL induces gene expression of <i>CD14</i>, <i>CD86</i>, <i>TLR2</i>, and <i>CD54</i> in resident lamina propria cells <i>in situ</i>. Tissue samples of total mucosa (TM) were collected prior to culturing (0 h TM) and simultaneously from both TM and LEL mucosa after completion of epithelial cell release by EDTA treatment (5 h TM, 5 h LEL-M) (see Fig. 1a). Subsequently, transcript levels of <i>CD14</i>, <i>TLR2</i>, <i>CD54</i>, and <i>CD86</i> were determined by qRT-PCR. Transcript numbers (normalized to 1000 transcripts <i>PPIB</i>) of “5 h LEL-M” were set to 1, and those of all other conditions were calculated as a fraction/multiple of 1. Shown are the mean normalized transcript numbers ± SEM of three or four independent experiments. Numbers in brackets indicate the absolute transcript numbers normalized to 1000 transcripts <i>PPIB</i>. Gray bars represent transcript levels of TM (0 h, 5 h), black bars represent transcript levels of LEL-M (5 h). (<b>B</b>) LEL induces protein expression of CD14 and CD86 in resident lamina propria cells <i>in situ</i>. Double immunofluorescence staining of CD68 (green) and CD14 or CD86 (red) in healthy total mucosa prior to culturing (TM t = 0 h) and after 5 h of culture (TM t = 5 h) as well as in mucosa immediately after LEL (LEL-M t = 5 h). Colocalization of both antigens is shown by yellow signals in the overlay. Magnification: x40. LEL enhances the expression of CD14 and CD86 on some CD68⁺ and a large pool of CD68⁻ cells. The results represent one of three independent experiments. (<b>C</b>) Quantification of CD14⁺ and CD86⁺ cells in TM 5 h and LEL-M 5 h, respectively. The mean numbers (± SEM) of CD14⁺ and CD86⁺ cells, respectively, per area of 100 CD68⁺ cells were determined with three areas/experimental condition being evaluated. Shown are the results of two independent experiments.