To explore the mechanism by which DHA inhibits the early alveolar inflammatory response in the rat BLM-induced PF model, we evaluated the Tgfb1, Jak2, and Stat3 mRNA expression and TGF-β1, JAK2, p-JAK2, STAT3, and p-STAT3 protein levels in lung tissues at day 7 after intratracheal administration of BLM, with and without DHA treatment, using qRT-PCR and immunohistochemistry staining. The gene discussed is JAK2; the disease is pemphigus foliaceus.