HIV-1 N-glycans are known to shield underlying epitopes towards the protective antibody repertoire. We previously described HIV-1 acute infection Env glycomutants designed from 3D-model in which the removal of clustered N-glycans did not disturb the envelope antigenicity, but increased the neutralization sensitivity. The potential of such immunogens to elicit neutralizing responses was estimated after rabbit immunizations with a DNA/protein protocol. Maturation of the Env-specific antibody response was confirmed by a change in avidity and conformational dependence. For one immunogen, the neutralizing response was increased with a higher breadth compared to the Wild-Type. Our data suggest that Env selective deglycosylation based on 3D data may represent a valuable strategy to improve elicitation of neutralizing antibodies.
The lamina propria that underlies and stabilizes the gut lining epithelium is densely populated with strategically located mononuclear phagocytes. Collectively, these lamina propria macrophages and dendritic cells (DC) are believed to be crucial for tissue homeostasis as well as the innate and adaptive host defense. Lamina propria DC were recently shown to gain direct access to the intestinal lumen by virtue of epithelium-penetrating dendrites. However, the role of these structures in pathogen uptake remains under debate. In this study, we report that entry of a noninvasive model pathogen (Aspergillus fumigatus conidia) into the murine small intestinal lamina propria persists in the absence of either transepithelial dendrites or lamina propria DC and macrophages. Our results suggest the existence of multiple pathogen entry pathways and-point at the importance of villus M cells in the uptake of gut lumen Ags. Interestingly, transepithelial dendrites seem altogether absent from the small intestine of BALB/c mice suggesting that the function of lamina propria DC extensions resides in their potential selectivity for luminal Ags, rather than in general uptake or gut homeostasis.