C-PC is not cytotoxic to macrophages (RAW 264.7). It promotes proliferation with a relative survival of 138% at 200 μg/mL. It reduces nitric oxide (NO) levels by 39% and 41.16% at concentrations of 50 and 200 μg/mL, respectively. It exhibits inhibitory effects on TNF-α by 74.32% and 100% at concentrations of 50 and 200 μg/mL. It also inhibits IL-6 by 30.44% and 75.76% at 50 and 200 μg/mL, respectively. At a dose of 30 μg/mL, phycocyanin shows higher inhibition of Collagen I (an indicator of idiopathic pulmonary fibrosis) and promotes cell recovery in the A549 cell line. Here, IL6 is linked to pulmonary fibrosis.