Bone loss is common in advanced cirrhosis, although the precise mechanisms underlying bone loss in cirrhosis are unknown. We studied the profile and functionality of boneâforming cells and boneâbuilding proteins in bone marrow (BM) of individuals with cirrhosis (n = 61) and individuals without cirrhosis as normal controls (n = 50). We also performed dual energy Xâray absorptiometry for clinical correlation. BM mesenchymal cells (MSCs) were analyzed for colonyâforming unitsâfibroblasts and their osteogenic (fibronectinâ1 [FN1], insulinâlike growth factor binding protein 3 [IGFBP3], collagen type 1 alpha 1 chain [COL1A1], runtârelated transcription factor 2 [RUNX2], and alkaline phosphatase, liver [ALPL]) and adipogenic ( adiponectin, C1Q, and collagen domain containing [ADIPOQ], peroxisome proliferatorâactivated receptor gamma [PPARÎł], and fatty acid binding protein 4 [FABP4]) potentials. Colonyâforming unitsâfibroblasts were lower in patients with cirrhosis (P = 0.002) than in controls. Cirrhotic BMâMSCs showed >2âfold decrease in osteogenic markers. Compared to controls, patients with cirrhosis showed fewer osteocytes (P = 0.05), osteoblasts, chondroblasts, osteocalcinâpositive (osteocalcin+) area, clusters of differentiation (CD)169+ macrophages (P < 0.001, each), and nestin+ MSCs (P = 0.001); this was more apparent in ChildâTurcotteâPugh (CTP) class C than A (P < 0.001). Multivariate logistic regression showed low nestin+ MSCs (P = 0.004) as a predictor of bone loss. Boneâresolving osteoclasts were comparable among CTP groups, but >2âfold decreased antiâosteoclastic and increased proâosteoclastic factors were noted in patients with CTP C compared to CTP A. Boneâbuilding proteins (osteocalcin [P = 0.008], osteonectin [P < 0.001], and bone morphogenic protein 2 [P = 0.001]) were decreased while antiâbone repair factors (fibroblast growth factor 23 [P = 0.015] and dipeptidyl peptidase 4 [P < 0.001]) were increased in BM and peripheral blood; this was more apparent in advanced cirrhosis. The dual energy Xâray absorptiometry scan T score significantly correlated with the population of osteoblasts, osteocytes, MSCs, and CD169+ macrophages. Conclusion: Osteoprogenitor cells are substantially reduced in patients with cirrhosis and more so in advanced disease. Additionally, increased antiâbone repair proteins enhance the ineffective bone repair and development of osteoporosis in cirrhosis. Hepatology Communications 2018;0:0â0)