Death Receptor 3 (TNFRSF25) Increases Mineral Apposition by Osteoblasts and Region Specific New Bone Formation in the Axial Skeleton of Male DBA/1 Mice

Figure 1

Expression of DR3 by murine OPCs and OBs. (a) DR  () and DR () OPCs and OB (DR , DR ) were analysed for DR3 signal by flow cytometry. DR3 signal was observed on DR OPCs and OBs. A small subpopulation of DR OPCs displayed higher levels of DR3 signal (shaded area = isotype control, black outline = DR3 antibody). (b) RNA was extracted from DR and DR OPCs and OB and tested for TL1A mRNA by RT-PCR. A 91 bp band corresponding to TL1A mRNA was detected at all time-points demonstrating constitutive expression of TL1A mRNA by DR and DR OPCs and OB. (c) Samples (DR , DR ) were tested by qPCR at time points indicated to determine whether DR3 signalling modulates (i) Runx2 or (ii) OSX gene expression. Increased expression of Runx2 was detected at day 7 and day 14 while increased OSX expression was only detected at day 14 in the DR compared to the DR.

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