Alteration of microbiota antibody-mediated immune selection contributes to dysbiosis in inflammatory bowel diseases.

Human secretory immunoglobulins (SIg) A1 and SIgA2 guide mucosal responses toward tolerance or inflammation, notably through reverse-transcytosis, the apical-to-basal transport of IgA2 immune complexes via M cells of gut Peyer's patches. As such, the maintenance of a diverse gut microbiota requires broad affinity IgA and glycan-glycan interaction. Here, we asked whether IgA1 and IgA2-microbiota interactions might be involved in dysbiosis induction during inflammatory bowel diseases.

Essential role of TOSO/FAIM3 in intestinal IgM reverse transcytosis.

Secretory immunoglobulin A (SIgA) can travel to and from the lumen and transport antigen to subepithelial cells. However, IgM can also multimerize into functional secretory component-bound immunoglobulin. While it is already known that both SIgA and SIgM undergo transcytosis to be secreted at the mucosal surface, only SIgA has been shown to perform retrotranscytosis through microfold cells (M cells) of the Peyer's patch.

NOD2 deficiency increases retrograde transport of secretory IgA complexes in Crohn's disease.

Intestinal microfold cells are the primary pathway for translocation of secretory IgA (SIgA)-pathogen complexes to gut-associated lymphoid tissue. Uptake of SIgA/commensals complexes is important for priming adaptive immunity in the mucosa. This study aims to explore the effect of SIgA retrograde transport of immune complexes in Crohn's disease (CD).

Comparison of three different ELISAs for the detection of recombinant, native and plasma IL-17A.

Plasma IL-17A detection in Langerhans Cell Histiocytosis (LCH) is currently a source of debate. Indeed, 500-P07G (PeproTech) and 41802 (R&D Systems) anti-IL-17A antibodies have been suspected to recognize nonspecific proteins. To resolve this discrepancy, we set up two new ELISAs by using 41802 or neutralizing eBio64CAP17 (eBioscience) capture monoclonal antibodies that we compared to the commercial PeproTech ELISA kit.

Impact of IgA isoforms on their ability to activate dendritic cells and to prime T cells.

Human IgA could be from different isotypes (IgA1/IgA2) and/or isoforms (monomeric, dimeric, or secretory). Monomeric IgA mainly IgA1 are considered as an anti-inflammatory isotype whereas dimeric/secretory IgA have clearly dual pro- and anti-inflammatory effects. Here, we show that IgA isotypes and isoforms display different binding abilities to FcαRI, Dectin-1, DC-SIGN, and CD71 on monocyte-derived dendritic cells (moDC).

Vaccination against Salmonella Infection: the Mucosal Way.

subspecies includes several serovars infecting both humans and other animals and leading to typhoid fever or gastroenteritis. The high prevalence of associated morbidity and mortality, together with an increased emergence of multidrug-resistant strains, is a current global health issue that has prompted the development of vaccination strategies that confer protection against most serovars. Currently available systemic vaccine approaches have major limitations, including a reduced effectiveness in young children and a lack of cross-protection among different strains.