Integrins are a large family of transmembrane proteins composed of an alpha and beta component. Integrins are involved in a diversity of biological functions such as cell adhesion, structure, differentiation, apoptosis and cell proliferation. They are the principal cell surface receptors that recognise cell to matrix interactions but little is known about the expression of beta 1 integrin family on airway smooth muscle (ASM) and their involvement in proliferation. This is a contributing factor in structural changes seen in asthma.