Modulation of isoforms of CD44 adhesion molecule in a murine model of gut-ischemia-reperfusion.

Gut ischemia-reperfusion (G-IR) induces a systemic inflammatory response, i n which leukocyte contribution to this injury in distant organs is importan t. ICAM-1 as well as CD11/CD18 have been involved in leukocyte infiltration in liver and lungs. CD44 adhesion molecule plays an essential role in othe r inflammatory processes such as rheumatoid arthritis and allergic contact dermatitis, however its implication in G-IR has not been described. In orde r to establish a possible role of CD44 in the development of systemic infla mmation by G-IR, we have studied CD44 mRNA expression by RT-PCR in a murine model of gut ischemia reperfusion. Animals subjected to G-IR showed an inc reased number of CD44 variable isoforms expressed in liver and spleen compa red to non-treated animals or animals subjected to laparotomy. This finding indicates that G-IR specifically induces the expression of different CD44 variable isoforms. Liver CD44 upregulation in animals subjected to G-IR sug gests a contribution of this molecule to lymphocyte activation and migratio n to this injured organ. Moreover, increased isoform expression in spleen m ay be induced by the proinflammatory environment resulting from a systemic depuration activity.