Evidence of particulate uptake by the gut of Atlantic salmon (Salmo salar L.)

Translocation of nanoparticles and Mycobacterium marinum across the intestinal epithelium in zebrafish and the role of the mucosal immune system

“…414 The size, shape and surface-properties of nano-/microparticles can have a 415 significant impact on cellular uptake, complement activation, immune response and 416 biodistribution in vivo (Oh and Park, 2014; Zolnik et al, 2010). Polystyrene particles 417with sizes between 100 nm and 10 µm were shown to be taken up in salmon intestine 418 to different degrees, but only 1 µm sized particles were rapidly transported to spleen 419 and kidney(Petrie and Ellis, 2006). The lack of transport of 1 µm sized polystyrene 420 particles to the spleen in our study may therefore be explained by possible different 421 size-dependent uptake dynamics.…”

Characterization of the cell-mediated cytotoxic responses of isogeneic ginbuna crucian carp induced by oral immunisation with hapten-modified cellular antigens

“…Nevertheless, the mechanism by which the responses are induced by oral administration of cellular antigens remains unclear. It is generally accepted that epithelial cells of the fish hindgut do not have the ability to take up particulate materials such as bacterial cells; however, a previous report on Atlantic salmon (Salmo salar) has provided evidence that anally administered polystyrene microparticles are taken up from the hindgut and transferred to internal organs [49]. We propose that the induction of cytotoxic responses against orally-delivered antigens is caused by specialized cells that capture the cellular debris taken up from the hindgut and then the degradation products (probably haptenated peptides) are loaded onto MHC molecules for presentation.…”

Reduced gut bacterial translocation in European sea bass (Dicentrarchus labrax) fed mannan oligosaccharides (MOS)

“…Although these leucocytes are present in and under the epithelium at all levels of the fish digestive tract, various studies have indicated that regional differences occur in organization of GALT at different levels of the digestive tract possibly reflecting specialized immunological functions [12]. In particular for sea bass, and based on the existence of an apparent gradient to concentrate the GALT toward the anus [12], the most important immunological function has been attributed to hindgut, where antigens appear to be taken up by enterocytes and transported to intraepithelial macrophages for processing and antigen presentation [7,9,13].…”