Anti-LIF monoclonal antibody, clone 0935

Bone tissues have trabecular bone with a high bone turnover and cortical bone with a low turnover. The mechanisms by which the turnover rate of these bone tissues is determined remain unclear. Osteocytes secrete sclerostin, a Wnt/beta -catenin signaling antagonist, and inhibit bone formation. We found that sclerostin expression in cortical bone is more marked than in trabecular bone in Sost reporter mice. Leukemia inhibitory factor (LIF) secreted from osteoclasts reportedly suppressed sclerostin expression and promoted bone formation. Here, we report that osteoclasts downregulate sclerostin expression in trabecular bone and promote bone turnover. Treatment of C57BL/6 mice with an anti-RANKL antibody eliminated the number of osteoclasts and LIF-positive cells in trabecular bone. The number of sclerostin-positive cells was increased in trabecular bone, while the number of beta -catenin-positive cells and bone formation were decreased in trabecular bone. Besides, Tnfsf11 heterozygous (Rankl(+/-)) mice exhibited a decreased number of LIF-positive cells and increased number of sclerostin-positive cells in trabecular bone. Rankl(+/-) mice exhibited a decreased number of beta -catenin-positive cells and reduced bone formation in trabecular bone. Furthermore, in cultured osteoclasts, RANKL stimulation increased Lif mRNA expression, suggesting that RANKL signal increased LIF expression. In conclusion, osteoclasts downregulate sclerostin expression and promote trabecular bone turnover.

We present a simple theoretical model study of negative ion conversion in neutral oxygen atom grazing scattering from a LiF(100) surface. A comparison of the calculated relative contributions of the image interaction and the Mott-Littleton polarization interaction to the electron-capture reaction energy defect implies that the image interaction can significantly reduce the electron-capture energy defect, in turn drastically increasing the electron-capture probability. This property means that the image interaction can play an important role in negative ion formation. Owing to the incorporation of detachment of the affinity electron of the formed negative ions by Coulomb repulsive barrier tunneling during the interaction with surface anion sites, our present theoretical results can well reproduce the experimental negative ion yield in the whole velocity range. Moreover, a comparison of the magnitudes of the image interaction for different optical limit dielectric constants reveals that a larger optical limit dielectric constant corresponds to a larger image interaction. This large image interaction can obviously reduce the energy defect of valence band electron capture, in turn increasing the electron-capture probability and finally leading to a significant increase in the negative ion yield in the scattered beam. This result implies that the selection of an ionic crystal with a large optical limit dielectric constant can pave the way to achieving a high negative ion yield and promote its various technical applications.