IFNG and osteoporosis: It has been reported that serum IFN‐γ levels in primary osteoporosis patients were significantly lower compared to health controls[49, 50] and in vitro production of IFN‐γ by peripheral CD4+ T cells in OP women was also significantly lower.[51] Over the past decades, the promoting effects of IFN‐γ on bone formation have been demonstrated by several studies,[32, 52, 53] but the underlying mechanism has not been clearly elucidated.