Fig. 4From: Digital quantification of p16-positive foci in fibrotic interstitial lung disease is associated with a phenotype of idiopathic pulmonary fibrosis with reduced survivalA Hematoxylin and eosin stained section of a fibroblastic focus in a case of IPF. B p16 immunohistochemistry of the same area. C p21 immunohistochemistry of the same area. D pRB immunohistochemistry of the same area. Objective magnification 20XBack to article page