Alpha-defensin-dependent enhancement of enteric viral infection
Fig 2
Naturally secreted α-defensins enhance MAdV-2 infection of small intestinal enteroids.
(A) Wild type and Mmp7-/- enteroids were infected with MAdV-2.IXeGFP via microinjection (circles, black line), basolateral infection (squares, green line), or disruption and mixing (triangles, blue line). The anticipated location of α-defensins (α) and virus (blue) relative to the enteroid cell layer (solid lines) are depicted for each route of infection in the schematics on the right. Viral titers from samples harvested on the indicated days were determined on CMT-93 cells. Data is the relative titer of progeny virus from wild type enteroids compared to Mmp7-/- enteroids from 3 independent experiments ± SD. (B) Expression of cryptdin 4 (Defcr4) relative to expression of ribosomal protein L5 (Rpl5) in wild type and Mmp7-/- enteroids from small intestine (SI) and colon was measured by qPCR four days after enteroid passage. Data are the average of two replicate experiments ± SD. (C) Representative images and (D) quantification of total GFP positive cells in wild type (WT, black columns) and Mmp7-/- (KO, white columns) small intestinal (SI) and colonic (C) enteroids at 24 h post-infection with MAdV-2.IXeGFP by microinjection. Virus was mixed with Texas Red-conjugated dextran (red in C) to mark injected enteroids. Data is the average number of GFP positive cells from ten microinjected enteroids from at least 9 independent experiments ± SEM. (E) Relative light units of wild type and Mmp7-/- small intestinal enteroids at 24 h post-infection with MAdV-2.IX2AFFluc by microinjection. Bars are colored as in (D). Data is the average of triplicate samples from 3 independent experiments ± SEM. **P<0.001; *P<0.05; ns, not significant.