Development and characterization of a rapidly proliferating, well-differentiated cell line derived from normal adult human osteoblast-like cells transfected with SV40 large T antigen

Abstract

A new bone cell line was established by transfecting normal adult human osteoblast-like (hOB) cells, derived from a 68-year-old woman, with the plasmid pSV3 neo. The plasmid included coding sequences and promotors for the large and small T antigens of the SV40 virus as well as resistance to the antibiotics neomycin and G418. A single antibiotic-resistant colony was located and cloned. Large tumor antigen production in the clonal cell line was confirmed by indirect immunofluorescence study. Treatment with 1,25-dihydroxy-vitamin D3 increased steady-state concentrations of protein and mRNA for osteocalcin and for alkaline phosphatase. Northern blot analyses also demonstrated the presence of mRNAs for alpha(I)-procollagen, osteopontin 1a, transforming growth factor beta, and interleukin-1 beta. The plasma membrane calcium pump and osteonectin were identified by immunocytochemical analysis. These cells produced a matrix that mineralized when beta-glycerophosphate was added to their cultures. As assessed by functional receptor assays, both estrogen and androgen receptors were present and functional, although at low concentrations. Treatment with parathyroid hormone did not stimulate adenylate cyclase activity. Thus, these cells are a well-differentiated, steroid-responsive clonal cell line that closely approximates the phenotype of the mature osteoblast. They should serve as an excellent model for the study of osteoblast biology.

Bioactive Glass Foam Scaffolds are Remodelled by Osteoclasts and Support the Formation of Mineralized Matrix and Vascular Networks In Vitro

“…Data from the ICP analysis of dissolution media indicates that concentrations of Ca in solution increase markedly (from 45 to 90 μgml −1 ) in the first 3 days and promote levels of cell proliferation similar to those observed in previous studies 27. The concentration of soluble silica released from bioactive glasses is well established as an independent inducer of osteoblastic proliferation, with negligible amounts of this element being present in standard growth media 7, 11, 13, 28. In the aforementioned studies, the rate of Si dissolution increases in the first few hours after immersion, similar to our observations.…”

Cx43 and Mechanotransduction in Bone

“…Similarly, oscillating fluid flow increased cell-to-cell coupling in MC3T3-E1 osteoblastic cells [22] and in MLO-Y4 osteocytic cells [21]. Cell membrane deformation to induce mechanical stimulation in single cells increased dye transfer in simian virus-40-immortalized human osteoblastic HOBIT cells [23,24], and induced calcium signal propagation between MC3T3-E1 osteoblastic cells and MLO-Y4 osteocytic cells [7]. Both effects were prevented by β-glycyrrhetinic acid, an agent that blocks connexin channels.…”

Osteoblastic cell secretome: A novel role for progranulin during risedronate treatment

“…Hobit cells, a line derived from normal adult human osteoblastic cells transfected with the T-antigen of the SV40 virus, retain most of the osteoblastic differentiation markers, including the expression of osteocalcin, alkaline phosphatase, type I collagen, osteopontin 1α, and the sensitivity to steroid hormones [34]. The term “secretome” refers to proteins released through classical as well as nonclassical secretory pathways [35].…”