Immortalized Human Fetal Osteoblast-SV40

Immortalized Human Fetal Osteoblast‑SV40 (hFOB1.19‑SV40) cells are human osteoblastic cells immortalized with the SV40 large T antigen. These cells were originally derived from fetal human bone and provide a conditionally proliferative osteoblastic cell line. The parental hFOB1.19 cell line was immortalized through transfection with the SV40 T antigen which is temperature sensitive to allow for proliferation while maintaining osteoblastic phenotypic characteristics (Keller et al., 1994). Primary osteoblasts isolated from tissues can only survive for a limited amount of time in vitro. Therefore, immortalized cells like hFOB1.19 cells allow for a more robust and reproducible osteoblastic model system.

The hFOB1.19‑SV40 cells are polygonal in shape with a fibroblast-like morphology and grow as adherent monolayers. They express osteoblast specific markers such as alkaline phosphatase (ALP), osteocalcin, bone sialoprotein and type I collagen, further confirming osteoblastic characteristics. When treated with differentiation media containing ascorbic acid and β‑glycerophosphate cells treated showed increased ALP activity and mineralization of the matrix, indicating the cells maintain osteogenic differentiation potential.

Immortalized human fetal osteoblast cells have been used to study osteoblast proliferation and differentiation, regulation of the extracellular matrix, mechanotransduction, evaluation of biomaterials, drug screening assays, bone remodeling as well as response to hormonal regulation such as vitamin D and parathyroid hormone.