The most abundant cell type in the lung interstitium is the fibroblast. Pulmonary fibroblasts (PF) exhibit typical fibroblast morphology, however, they also possess some distinguishing features such as long, branching processes and gap junctions. PF function to produce type III collagen, elastin, and proteoglycans of the extracellular matrix of the alveolar septa. PF also play an important role in the repair and remodeling processes following tissue damage. The controlled accumulation of fibroblasts to sites of inflammation is crucial to effective tissue repair after injury. An inadequate or an excessive accumulation of fibroblasts results in abnormal tissue function and can lead to the development of pulmonary fibrosis. Notably, pulmonary fibrosis has been observed in acute COVID-19 patients, however, little is known about how the fibrosis will affect lung function in recovered patients. The culture of mouse PF (MPF) in vitro can be used to further elucidate the mechanisms of pulmonary fibrosis and other types of lung disorders. MPF from ScienCell Research Laboratories are isolated from CD-1 IGS mouse lung. MPF are cryopreserved at passage one and delivered frozen. Each vial contains >5 x 105 cells in 1 ml volume. MPF are characterized by immunofluorescence with antibody specific to fibronectin. MPF are negative for mycoplasma, bacteria, yeast, and fungi. MPF are guaranteed to further expand for 5 population doublings under the conditions provided by ScienCell Research Laboratories. Recommended Medium It is recommended to use Fibroblast Medium (FM, Cat. #2301) for culturing MPF in vitro.