#1, Does endogenous SOCS3 protein come up on WB? Fig2A shows that SOCS3 is not present (or not detectable) in cells. ---If this endogenous SOCS3 is not detectable, shRNA study for SOCS3 might represent non-specific effect on MMP13 gene expression in this system.

#2, Was MMP13 protein detectable? ---If MMP13 is functional molecule for osteoblast function, MMP13 must be expressed as protein in this cell line. Detecting MMP13 in culture media can confirm this. These detecting SOCS3 and MMP13 are very important to discuss about the function of these molecules in osteoblast.

#3, Is there any difference in differentiation status in SOCS3 overexpressed and shRNA treated cells with or without LPS treatment? ---This phenomena might relate to differentiation status of osteoblast or the action of osteoblast dependent ECM turn-over, so showing and discussing the point in this manuscript (or report in future) explains biological significance of this study.