The polysaccharide chitosan stimulates intestinal epithelial cells to produce immunomodulatory signals.

-CANALI MM, PIÑAS G, ECHENIQUE J, CORREA SG.

Viña del Mar, Chile

Congreso; 9th Latin American Congress of Immunology (ALAI)-XII Chilean Society of Immunology Congress; 2009

Sociedad Latinoamericana y Sociedad Chilena de Inmunología

Intestinal epithelial cells (IECs) sense and limit the exposure to luminal antigens. Chitosan (Ch) is a polycationic polysaccharide that triggers regulatory cytokine release and promotes tolerance at the mucosal inductive sites. To evaluate the effects of Ch on IECs we fed rats diluent or 3 mg Ch and 16 h later we isolated IECs and we evaluated cytokine content in culture supernatants (antibody cytokine array and ELISA). Over fourteen factors found in diluent rats were also detected in Ch group. Levels of IL-10 or IL-6 (p<0.05) and TGF-b increased upon Ch feeding (p<0.05). IECs release thymic stromal lymphopoietin (TSLP) to condition DCs. To study TSLP in our rat model we designed primers within sequences homologous to mouse TSLP mRNA and we performed RT-PCR. We amplified and isolated a single band that was cloned into a plasmid vector and sequenced. The homology of rat TSLP mRNA was 100% with TSLP like mRNA. Then, we started to evaluate by real time PCR the ability of Ch to induce the expression of this cytokine in rats after acute or chronic administration. Together these results show the ability of Ch to stimulate IECs to produce immunomodulatory factors that could be relevant in intestinal homeostasis.