hFOB 1.19 is an osteoblast cell line that was established by transfection of limb tissue obtained from a spontaneous miscarriage with the temperature sensitive expression vector pUCSVtsA58 and the neomycin resistance expression vector pSV2-neo. Clones were selected in the presence of 0.6 mg/mL G418. The cells provide a homogenous, rapidly proliferating model system for studying normal human osteoblast differentiation, osteoblast physiology, and hormonal, growth factor, and other cytokine effects on osteoblast function and differentiation. This product is an ATCC manufactured and accessioned progeny of ATCC CRL-11372 cited in US Pat. No. 5,681,701.