Lymphocyte adhesion molecules and their role in homing
| Receptor . | Expression on Lymphocytes . | Ligands . | Interacting Cells/Substrates . | Predominant Role(s) in Homing . |
|---|---|---|---|---|
| L-selectin | Resting T and B cells | PNAd GlyCAM CD34 (MAdCAM-1) | High endothelial venules | Peripheral lymph node-homing |
| CLA | Memory T-cell subset | E-selectin | Endothelium (skin) | Skin-homing |
| αLβ2 (LFA-1) | Broad expression on T and B cells | ICAM-1 ICAM-2 ICAM-3 | Endothelium High endothelial venules Dendritic cells FDC Activated epithelium | Broad function in lymphocyte homing |
| α4β1 (VLA-4) | Broad expression on T and B cells | VCAM-1 Fibronectin (CS-1) | Activated endothelium Dendritic cells FDC | Homing to inflammatory sites |
| α4β7 | Naive T and B cells (low) Memory T-cell subset (high) Peripheral B-cell subset (low) | MAdCAM-1 (VCAM-1) (Fibronectin) | Endothelium of intestinal mucosa Peyer patch and mesenteric lymph node high endothelial venules | Gut-homing |
| αEβ7 | Intraepithelial T cells | E-cadherin | Epithelium | Epitheliotropism |
| CD44 (multiple isoforms) | Broad expression on T and B cells Splice variants on activated T and B cells | Hyaluronate Collagen IV Fibronectin Serglycin Osteopontin Growth factors (FGF-2, HGF, MIP-1β) | Extracellular matrix Endothelium | Homing to sites of inflammation Modulation of cell growth and motility |
| Receptor . | Expression on Lymphocytes . | Ligands . | Interacting Cells/Substrates . | Predominant Role(s) in Homing . |
|---|---|---|---|---|
| L-selectin | Resting T and B cells | PNAd GlyCAM CD34 (MAdCAM-1) | High endothelial venules | Peripheral lymph node-homing |
| CLA | Memory T-cell subset | E-selectin | Endothelium (skin) | Skin-homing |
| αLβ2 (LFA-1) | Broad expression on T and B cells | ICAM-1 ICAM-2 ICAM-3 | Endothelium High endothelial venules Dendritic cells FDC Activated epithelium | Broad function in lymphocyte homing |
| α4β1 (VLA-4) | Broad expression on T and B cells | VCAM-1 Fibronectin (CS-1) | Activated endothelium Dendritic cells FDC | Homing to inflammatory sites |
| α4β7 | Naive T and B cells (low) Memory T-cell subset (high) Peripheral B-cell subset (low) | MAdCAM-1 (VCAM-1) (Fibronectin) | Endothelium of intestinal mucosa Peyer patch and mesenteric lymph node high endothelial venules | Gut-homing |
| αEβ7 | Intraepithelial T cells | E-cadherin | Epithelium | Epitheliotropism |
| CD44 (multiple isoforms) | Broad expression on T and B cells Splice variants on activated T and B cells | Hyaluronate Collagen IV Fibronectin Serglycin Osteopontin Growth factors (FGF-2, HGF, MIP-1β) | Extracellular matrix Endothelium | Homing to sites of inflammation Modulation of cell growth and motility |
Only molecules discussed in the present paper are listed. The αβ heterodimers belong to the integrin family. CLA indicates cutaneous lymphocyte antigen; FDC, follicular dendritic cells; FGF, fibroblast growth factor; GlyCAM, glycosylation-dependent cell adhesion molecule; HGF, hepatocyte growth factor; ICAM, intercellular adhesion molecule; LFA, lymphocyte function-associated; MAdCAM, mucosal addressin cell adhesion molecule; MIP, macrophage inflammatory protein; PNAd, peripheral lymph node addressin; VCAM, vascular cell adhesion molecule; VLA, very late antigens.