Inactivation of the integrin beta 6 subunit gene reveals a role of epithelial integrins in regulating inflammation in the lung and skin.

Lung Biology Center, University of California, San Francisco 94143, USA.
The Journal of Cell Biology (Impact Factor: 9.83). 06/1996; 133(4):921-8.
Source: PubMed


The integrin alpha v beta 6 is only expressed in epithelial cells. In healthy adult epithelia, this receptor is barely detectable, but expression is rapidly induced following epithelial injury. Mice homozygous for a null mutation in the gene encoding the beta 6 subunit had juvenile baldness associated with infiltration of macrophages into the skin, and accumulated activated lymphocytes around conducting airways in the lungs. Beta 6-/- mice also demonstrated airway hyperresponsiveness to acetylcholine, a hallmark feature of asthma. These results suggest that the epithelial integrin alpha v beta 6 participates in the modulation of epithelial inflammation. Genetic or acquired alterations in this integrin could thus contribute to the development of inflammatory diseases of epithelial organs, such as the lungs and skin.

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    • "In humans, αv is up-regulated during wound healing (Cavani et al., 1993; Clark et al., 1996). Young β6 -/-mice do not display wound healing defects; however, wound healing is delayed in aged β6 null mice compared to age-matched controls (AlDahlawi et al., 2006; Huang et al., 1996). In contrast, constitutive expression of β6 in the epidermis leads to formation of chronic wounds (Häkkinen et al., 2004). "
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    • "Interestingly, although mice lacking the TGF␤-activating integrin ␣v␤8 on immune cells develop autoimmunity, this is not as severe as mice that lack global function of integrins ␣v␤6 and ␣v␤8 (Aluwihare et al. 2009). Global integrin ␣v␤6−/− mice develop only mild inflammation of the lung and skin (Huang et al. 1996). "
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