Identification of select lymphocyte homing molecules and vascular addressins in lymphotoxin-alpha deficient mice

The transmigration of lymphocytes across vascular endothelium is a critical step for the localization of lymphocytes to lymph nodes in both naive and immune reactive states. Mice deficient in lymphotoxin-alpha (LT-alpha) lack peripheral and gut associated lymph nodes: Lymphocyte function and homing ability are,reported to be normal in these mice yet information regarding c ell adhesion molecules and counterpart vascular addressins is lacking. The phenotype of peripheral lymphocytes from LT-alpha deficient mice was invest igated by the use of fluorescent activated cell sorting and immunohistochem istry. No difference was detected in the splenocyte and tissue expression o f L-selectin, alpha(4)beta(7) or its individual integrin components, mucosa l addressin cell adhesion molecule (MAdCAM-1), intracellular adhesion molec ule (ICAM-1), peripheral node addressin (PNAd), or platelet/endothelial cel l adhesion molecule (PECAM-1) between wild-type and LT-alpha deficient mice . Therefore, impaired expression of these lymphocyte homing and vascular ad dressin molecules is apparently not included in the phenotype of the LT-alp ha deficient mouse.