Immunohistochemical studies on the expression of surfactant proteins in sheep lungs with ovine pulmonary adenocarcinoma

The expression of surfactant proteins in sheep lungs with OPA was studied on immunostaining. Grossly, the OPA lungs revealed diffuse areas of consolidation and microscopically, proliferation of alveolar and bronchiolar epithelial cells either in papillary or acinar pattern.The positive immunostaining for SP-A, SP-B and SP-C was noticed in the neoplastic epithelial cells. Of these SP-A and SP-B were seen in both alveolar type II pneumocytes and bronchial clara cells whereas SP-C was as pecific marker for type II pneumocytes. The present study characterized the neoplastic cells as alveolar type II pneumocytes.