Adhesion Molecule Expression and Adhesion Properties of Murine Intestinal Intraepithelial Lymphocyte Hybridomas

We used mouse intraepithelial lymphocyte hybridomas (IELH) to study the role of adhesion molecules, especially β7 integrins, in the adherence of IELH to intestinal epithelial cells. Unstimulated 9.1γδ IELH cells expressed high levels of CD11a, CD11a/CD18, CD44, and CD45; medium levels of CD45RB and integrin α4; low levels of αM290, β7, and 33D1; and very low levels of ICAM-1 and VCAM-1. PHA and TGF-β stimulated IELH cells--but not control BW5147 cells (α4/β7 integrin negative fusion partner)--to bind to IEC-18 and CMT-93 intestinal epithelial cells, but not to renal mesangial cells. The binding was partially blocked by mAbs to integrin α4 and/or αM290. The two mAbs in combination did not completely block the binding, suggesting that epitopes not recognized by these two mAbs are also involved in binding. The adhesion of 9.1γδ cells to IEC-18 cells was also partially inhibited by mAbs to VCAM-1, LFA-1, and CD44, but not by mAbs CD45 and a control rat IgG. Thus, IELH may be a useful model system with which to study the role of adhesion molecules in the interaction between IEL and intestinal epithelial cells.