Adhesion molecules and lymphocyte homing 成员：艾戈弋、鲍梦馨、车飞、陈超、董丽花、姜琳

review

Definition of adhesion molecules Cell adhesion molecules (CAMs) are cell surface proteins involved in the interaction of cell-cell or cell-extracellular matrix. CAMs take effect by the binding of receptor and ligand

Classification Integrin family Selectin family Immunoglobulin (Ig) superfamily Cadherin family Mucin-like family Other adhesion molecules

Integrins

Selectin

ISF

Cadherin

Lymphocyte homing The directed migration of subsets of circulating lymphocytes into particular tissue sites.

Classification Lymphoid stem cell migrate to central lymphoid organs Mature lymphocyte migrate to peripheral lymphoid organs Recirculation of lymphocytes Lymphocyte migrate to the sites of inflammation

How adhesion molecules participate in homing ?

Adhesion molecules mediate the process of homing Lymphocyte homing receptor (LHR) express on lymphocyte Addressin express on vascular endothelial cell

Adhesion Molecules on Lymphocyte

lymphocyte adhere, penetrate vascular endothelial cell

Adhesion molecules participate in lymphocyte homing Lymphocyte homing receptor Addressins Adhesion molecules Functions L-selectin Lymphocyte homing to peripheral immune organs PNAd　 Addressin of peripheral high venous endothelial cell CLA Receptor on memory T cell surface for directionally homing to skin E-selectin Express on vascular endothelial cell of inflammation portion of skin LFA-1 Participate in many lymphocytes for homing ICAM-1 ICAM-2

Adhesion molecules participate in lymphocyte homing Lymphocyte homing receptor Addressins Adhesion molecules Functions VLA-4 Receptor of lymphocyte homing VCAM－1 Express on vascular endothelial cell of inflammation portion CD44 Participate in many lymphocytes homing MAd Intestinal lymphatic tissue and lamina propria integrin Receptor of lymphocyte for directionally migrate to Peyre's Patch MAd　 Addressin of vascular endothelial cell α4β7

Adhesion molecules in normal condition in lymphocyte homing

Pro-T cell migrate to thymus Homing receptor: CD44 and L-selectin expressed by pro-T cell Adressin: EA1 molecule expressed by thymus vascular endothelial cell And integrin α6β1、α6β4 play an important role in adhesion of pro-T cell

Lymphocyte migrate to peripheral lymphoid organs Lymphocytes migrate to lymph node Homing receptor: L-selectin on lymphocyte Adressin：peripheral lymphonode vascular addressin (PNAd) LFA-1/ICAM-1、ICAM-2 and CD44/Mad molecules participate in the adhesion and penetration

Lymphocyte migrate to peripheral lymphoid organs Lymphocyte migrate to Peyer’s Patch Homing receptor: integrin α4β7 molecule； CD44 and LFA-1 molecules Adressin: Vascular endothelial cell of peyre’s patch specifically highly express mucosal vascular addressin (Mad); ICAM-1、ICAM-2 Peyre’s patch means the aggregated lymphoid nodule in small intestine.

Lymphocyte homing

Adhesion molecules in pathological condition (inflammation) in lymphocyte homing

Function of adhesion molecules in inflammation

Lymphocyte migrate to inflammation of skin Homing receptor: cutaneous lymphocyte-associated antigen (CLA)；VLA-4；LFA-1 Adressin: E-selectin ；VCAM-1; ICAM-1/ICAM-2

Lymphocyte migrate to inflammation of skin

Lymphocyte migrate to inflammation of intestinal mucosa Molecule expressed by lymphocyte of intestinal mucous tissue called mucosal lymphocyte antigen (MLA)

Lymphocyte migrate to inflammation of synovium Homing receptor: LFA-1 ; VLA-4 ; CD44 Adressin: ICAM-1；VCAM-1；Mad

Disease Hyper-expressing adhesion molecules Hypo-expressing adhesion molecules

more mechanism needed to be explored… However… more mechanism needed to be explored…

Thank you