Deficiency of the Collagen Endocytic Receptor MRC2 Accelerates Mouse Lung Fibroblast Proliferation

Mannose receptor C type 2 (MRC2) is highly expressed in the lung and is the major endocytic receptor for the internalization and degradation of collagen in mesenchymal cells. Using Mrc2 knockout (KO) mice, we previously showed that MRC2 is required for efficient clearance of collagen in bleomycin-induced fibrosis. However, MRC2 also interacts with various cell-surface receptors and ligands beyond collagens, indicating that MRC2 may have additional, previously unrecognized functions in fibroblasts. To uncover novel pathways regulated by MRC2, we took an unbiased approach to compare the transcriptomic profile of MRC2-deficient lung fibroblasts to WT after in vitro culture.