Abstract:
Background. Osteoarthritis (OA) is a degenerative disease that progressively involves all joint
compartments leading to destruction and loss of function. Regenerative medicine (RM) aims to
introduce revolutionary therapies dedicated to drastically improve the way we treat degenerative
diseases including OA. Explanted cartilage tissue has been proposed as a modality to study cartilage
ontogeny and to understand cartilage repair as well as modality to screen new drug/therapies for the
treatment of OA.
Objectives. To establish a working protocol for obtaining human osteochondral tissue explants in
co
-culture with synovial tissue to be used as ex vivo models for OA and to demonstrate
explantreactivity to conditioned media (CM) from adipose mesenchymal cells (ADSC) tested as a
modality
for bone and cartilage rescue.
Methods. Human osteochondral samples were collected from patients undergoing total knee
replacement were kept in incomplete chondrogenic media (ICM) or in serum free DMEM.Explantreleased cytokines were quantified by. ELISA for Human tumor necrosis factor alpha(TNFα) and
interleukin -6 (IL-6) and qPCR-based immunoassay for Human IL-17A and Human IL-1β
(Proquantum™ immunoassay kit Invitrogen). Histology, Western blot and
Immunohistochemistrystudies to detect Collagen type II (Col II) matrix metalloprotease 1 and 13
(MMP I, MMP-13),Perlecan and beta galactosidase (BGAL) are going on.
Results. We found that culture media as well as synovial tissue presence influences the level
ofdetectable IL-6, IL-17A CM increased IL-6 presence up to 29 days in culture; TNF α and IL1B
levelsdecrease after 7 days in culture; CM treatment significantly decrease TNF α in both
synoviumcontaining DMEM and ICM cultured explants Histology revealed presence of active
chondrocytewith enlarged hyperchromatic nuclei in CM treated explants.
Conclusion. Time in culture, type of culture media and synovial presence influence explant
reactivity. Presence of synovial tissue increase explant reactivity especially for situation when an
antiinflammatory effect is expected. Histology and immunohistochemistry can detect markers of tissue
regeneration. Explant culture can serve as a reliable ex vivo model for testing both antiinflammatory
as well as tissue remodeling intervention for articular joint repair.
