The adrenal gland plays an essential role in regulating homeostasis in the body through the secretion of corticosteroid and androgen hormones. Fibroblasts are mesenchymal cells derived from the embryonic mesoderm. They have been extensively used for a wide range of cellular and molecular studies. This is mainly because they are one of easiest types of cells to grow in culture, and their durability makes them amenable to a wide variety of manipulations ranging from studies employing gene transfection to microinjection. Fibroblasts secrete a non-rigid extracellular matrix that is rich in type I and/or type III collagen. They are responsible for much of the synthesis of extracellular matrix in connective tissues and play major roles in wound healing. Many diseases are associated with fibroblasts, either because fibroblasts are implicated in their etiology or because of the fibrosis that accompanies damage to other cell types in tissues. For example, the development of bowl stenosis in Crohn's disease patients is caused by extreme fibroblast proliferation and extracellular matrix expansion.HAdF from Bioarray Research Laboratories are isolated from human adrenal tissue. HAdF are cryopreserved at passage one and delivered frozen. Each vial contains >5 x 10^5 cells in 1 ml volume. HAdF are characterized by their spindle morphology and immunofluorescence with antibody specific to fibronectin. HAdF are negative for HIV-1, HBV, HCV, mycoplasma, bacteria, yeast and fungi. HAdF are guaranteed to further expand for 15 population doublings under the conditions provided by Bioarray Research Laboratories.