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.
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.
Authors: Mats W Johansson; Shih-Tsung Han; Kristin A Gunderson; William W Busse; Nizar N Jarjour; Deane F Mosher Journal: Am J Respir Crit Care Med Date: 2012-01-06 Impact factor: 21.405
Authors: Oleg S Matusovsky; Emily M Nakada; Linda Kachmar; Elizabeth D Fixman; Anne-Marie Lauzon Journal: J Physiol Date: 2014-03-31 Impact factor: 5.182
Authors: Deepa Rastogi; John Nico; Andrew D Johnston; Toni Adrianne M Tobias; Yurydia Jorge; Fernando Macian; John M Greally Journal: J Allergy Clin Immunol Date: 2017-05-04 Impact factor: 10.793
Authors: Laila A Al-Alwan; Ying Chang; Andrea Mogas; Andrew J Halayko; Carolyn J Baglole; James G Martin; Simon Rousseau; David H Eidelman; Qutayba Hamid Journal: J Immunol Date: 2013-07-31 Impact factor: 5.422