Format

Send to:

Choose Destination
See comment in PubMed Commons below
Am J Respir Crit Care Med. 2010 Aug 1;182(3):317-24. doi: 10.1164/rccm.200905-0745OC. Epub 2010 Apr 15.

T Cells localize with proliferating smooth muscle alpha-actin+ cell compartments in asthma.

Author information

  • 1Meakins-Christie Laboratories, McGill University, Montreal, PQ, Canada.

Abstract

RATIONALE:

Airway remodeling in asthma comprises increased airway smooth muscle (ASM), an alteration linked to airway hyperresponsiveness and disease severity. Experimental studies showed that T cells adhere to ASM through vascular cell adhesion molecule-1 (VCAM-1) and drive ASM growth through direct contact between the T cells and smooth muscle alpha-actin (alpha-SMA)(+) cells.

OBJECTIVES:

To support the hypothesis of a T-cell/alpha-SMA(+) cell contact mechanism of ASM remodeling in asthma, using bronchial biopsies.

METHODS:

We performed quantitative morphology on T cells, proliferating cell nuclear antigen (PCNA), alpha-SMA, and VCAM-1 on biopsies from subjects with moderate and severe asthma and healthy control subjects.

MEASUREMENTS AND MAIN RESULTS:

We demonstrate ASM cell proliferation and infiltration by T cells in proportion to severity in the subjects with asthma. T cells localized with alpha-SMA(+)PCNA(+) cells, suggesting direct intercellular contact and a relationship with alpha-SMA(+) cell proliferation. Furthermore, the subjects with asthma developed a proliferating compartment of subepithelial alpha-SMA(+), nonorganized airway contractile elements (NOACE), suggesting a phenotype gradient from undifferentiated cells to smooth muscle-like cells. T-cell juxtaposition events were also observed in this compartment and correlated to its mass. The subjects with asthma showed VCAM-1 expression in postcapillary venules and clusters of VCAM-1 immunoreactivity in ASM and NOACE, consistent with a role of VCAM-1 in T-cell/alpha-SMA(+) cell interaction.

CONCLUSIONS:

T cells may induce alpha-SMA(+) cell proliferation through direct intercellular contact. NOACE may in part contribute to ASM growth through differentiation and translocation of alpha-SMA(+) cells. The findings support the role of the T cell in ASM remodeling in asthma.

PMID:
20395563
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Atypon
    Loading ...
    Write to the Help Desk