Immunological differences in intestine and rectum of Atlantic cod (Gadus morhua L.)

Francisella noatunensis in Atlantic cod (Gadus morhua L.); waterborne transmission and immune responses

“…The generally lower expression of cytokines in intestine and rectum compared to the spleen and head kidney could be due to the lower number of immune cells in gastrointestinal organs as reported in Atlantic cod [15]. Even though the expression level was not as high as in spleen or head kidney, a certain regulation of cytokines were observed in intestine and rectum and this suggests an involvement of the intestinal mucosal immune system during F. noatunensis infections.…”

“…Many of these immune genes show a rapid up-regulation, sometimes within hours after challenge with inactivated bacteria or bacterial antigen such as lipopolysaccharide (LPS). Moreover, it has been shown that Atlantic cod lack a second gut segment and that the rectal tissue differs from other parts of the gut and has a different distribution of immune cells compared to the distal intestine [15]. How cod responds to a live intracellular bacterium such as F. noatunensis is still unknown.…”

A Review of Immune System Components, Cytokines, and Immunostimulants in Cultured Finfish Species

“…These T cells can be further divided into regulator and effector populations in order to examine the adaptive response [55]. Atlantic cod (Gadus morhua), in comparison to the foregut and stomach regions [57]. This finding coincides with the known adaptive immunocompetency of the distal intestine, and elaborates on the ability for immunoglobulins to aggregate in specified regions aside from traditional GALT.…”

Immune Defences of Teleost Fish

“…The lack of any comprehensive data regarding the functional role of dendritic cells (DCs) in the gut mucosa of teleost fish may suggest that the predominant APC that primes adaptive responses is the macrophage cell; however, DCs are likely to exist as the DC differentiation marker CD83 has been characterized in teleost and elasmobranch fish (Ohta et al 2004). Gut macrophages have been described in a number of teleost fish (Rombout et al 1986;Georgopoulou and Vernier 1986;Inami et al 2009) and have been shown to increase in density of numbers upon anal/intestinal antigenic challenge and to present antigenic determinants at their surface upon processing (Rombout et al 1985;1986;Rombout and van den Berg 1989a). These antigenic determinants, like mammalian systems, are presented in the context of MHC molecules where MHC I gene products are expressed on all nucleated cells in teleost fish ; upon vaccination, MHC II was demonstrated to be highly inducible in the head kidney, spleen, hindgut and gills of the Atlantic salmon (Koppang et al 1998).…”

“…Although gut macrophages are morphologically described in a variety of teleosts (Georgopoulou and Vernier 1986;Temkin and McMillan 1986;Rombout et al 1986;Inami et al 2009) their number, size and Ig-binding capacity vary among species. In particular, cyprinid fish have many macrophage-like cells in and under the intestinal epithelium and their number is increased after anal intubation with antigens (Davina et al 1980;Rombout et al 1985;1989a).…”