Osteoarthritis (OA) is one of the most frequent musculoskeletal disorders and represents the main indication for total joint arthroplasty. Multipotent mesenchymal stromal cells (MSCs) can be easily isolated and culture expanded from bone marrow aspirates and provide an excellent source of progenitor cells for cell-based regeneration strategies due to their ex vivo differentiation and proliferation capacity. Although there are hints that MSCs derived from OA patients may exhibit altered function the role of MSCs with respect to disease development and progression of OA is not clearly understood to date. To assess whether advanced-stage OA affects MSCs' suitability for musculoskeletal regenerative therapy, in the present study, we compare proliferation and differentiation potential of MSCs from osteoarthritic versus healthy donors.

Clinical data (range of motion of lower limb joints, sociodemographic score dataset, WOMAC score, EQ-5D score, Harris Hip Score, radiological evaluation (OA group only), routine laboratory parameters, and bone metabolism parameters)

Osteogenic, chondrogenic, and adipogenic differentiation is proofed qualitatively by cell staining

osteogenic, chondrogenic and adipogenic marker gene expression analysis using quantitative real-time RT-PCR

cell-specific alkaline phosphatase (ALP) activity assay

large-scale gene expression profile

Fluorescence-activated cell sorting (FACS)- CD44, CD105 (SH2; endoglin), CD106 (vascular cell adhesion molecule; VCAM-1), CD166, CD29, CD73 (SH3 and SH4), CD90 (Thy-1), CD117, STRO-1 and Sca-1 [%]

Inclusion Criteria:

• indication for hip THR
• primary osteoarthritis of the hip
• Patient's consent

Exclusion Criteria:

• secondary osteoarthritis of the hip
• Any malignancies
• infectious disease
• rheumatic disease
• osteoporosis
• Any additional serious disease complicating the participation in this study

pelvic compartment advanced-stage (Kellgren and Lawrence grade 3 or 4, mean 67±6 years) osteoarthritic and age-matched healthy donors