Lymphocyte homing to bronchus-associated lymphoid tissue (BALT) is mediated by L-selectin/PNAd, alpha4beta1 integrin/VCAM-1, and LFA-1 adhesion pathways.
J Exp Med
; 197(10): 1255-67, 2003 May 19.
Article
in En
| MEDLINE
| ID: mdl-12756264
ABSTRACT
Bronchus-associated lymphoid tissue (BALT) participates in airway immune responses. However, little is known about the lymphocyte-endothelial adhesion cascades that recruit lymphocytes from blood into BALT. We show that high endothelial venules (HEVs) in BALT express substantial levels of VCAM-1, in marked contrast to HEVs in other secondary lymphoid tissues. BALT HEVs also express the L-selectin ligand PNAd. Anti-L-selectin, anti-PNAd, and anti-LFA-1 mAbs almost completely block the homing of B and T lymphocytes into BALT, whereas anti-alpha4 integrin and anti-VCAM-1 mAbs inhibit homing by nearly 40%. alpha4beta7 integrin and MAdCAM-1 are not involved. Importantly, we found that mAbs against alpha4 integrin and VCAM-1 significantly block the migration of total T cells (80% memory phenotype) but not naive T and B cells to BALT. These results suggest that an adhesion cascade, which includes L-selectin/PNAd, alpha4beta1 integrin/VCAM-1, and LFA-1, targets specific lymphocyte subsets to BALT. This high level of involvement of alpha4beta1 integrin/VCAM-1 is unique among secondary lymphoid tissues, and may help unify lymphocyte migration pathways and immune responses in BALT and other bronchopulmonary tissues.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Bronchi
/
Lymphocytes
/
Vascular Cell Adhesion Molecule-1
/
L-Selectin
/
Integrin alpha4beta1
/
Lymphoid Tissue
/
Antigens, Surface
Type of study:
Risk_factors_studies
Limits:
Animals
Language:
En
Journal:
J Exp Med
Year:
2003
Type:
Article
Affiliation country:
United States