P.K. Bos

Effect of Arthritic Synovial Fluids on the Expression of Immunomodulatory Factors by Mesenchymal Stem Cells: An Explorative in vitro Study

Background: In diseased joints, the catabolic environment results in progressive joint damage. Mesenchymal stem cells (MSCs) can have immunomodulatory effects by secreting anti-inflammatory factors. To exert these effects, MSCs need to be triggered by pro-inflammatory cytokines. To explore the potential of MSCs as a treatment for diseased joints, we studied the effect of synovial fluid (SF) from donors with different joint diseases and donors without joint pathology on the immunomodulatory capacities of human MSCs in vitro. We hypothesized that SF of diseased joints influences the immunomodulatory effects of MSCs. Materials and Methods: MSCs were cultured in medium with SF of six osteoarthritis (OA) or six rheumatoid arthritis (RA) donors and three donors without joint pathology were used as control. Gene expressions of IL-6, HGF, TNFa, TGFb1, and indoleamine 2,3-dioxygenase (IDO) were analyzed. l-kynurenine concentration in conditioned medium (CM) by MSCs with SF was determined as a measure of IDO activity by MSCs. Furthermore, the effect of CM with SF on proliferation of activated lymphocytes was analyzed. Results: Addition of SF significantly up-regulated the mRNA expression of IL-6 and IDO in MSCs. SF(OA) induced significantly higher expression of IDO than SF(control), although no difference in IDO activity of the MSCs could be shown with a l-kynurenine assay. Medium conditioned by MSCs with SF(OA or RA) suppressed activated lymphocyte proliferation in vitro more than medium conditioned by MSCs without SF or with SF(control). Discussion: SF can influence the expression of genes involved in immunomodulation by MSCs and the effect on lymphocyte proliferation. We found indications for disease-specific differences between SFs but the variation between donors, even within one disease group was high. These data warrant further research to examine the potential application of MSC therapy in arthritic joints.

Age-related differences in articular cartilage wound healing: A potential role for transforming growth factor β1 in adult cartilage repair

Objective of this study was to investigate the early wound healing reactions of immature and mature articular cartilage on experimental wound healing in the New Zealand White rabbit. The proliferation potential and glycosaminoglycan production of isolated chondrocytes of these animals was studied in an alginate culture system. A band of tissue with death chondrocytes was observed at wound edges of immature articular cartilage, whereas mature cartilage showed a significant smaller amount of dead chondrocytes. A general increase in TGFbeta1, FGF2 and IGF1 was observed throughout cartilage tissue with the exception of lesion edges. The observed immunonegative area appeared to correlate with the observed cell death in lesion edges. Repair in immature cartilage was indicated by chondrocyte proliferation in clusters and a decrease in defect size. No repair response was observed in mature articular cartilage defects. The alginate culture experiment demonstrated a higher proliferation rate of immature chondrocytes. Addition of recombinant TGFbeta1 increased proliferation rate and GAG production of mature chondrocytes. We were not able to further stimulate immature chondrocytes. These results indicate that TGFbeta1 addition may contribute to induce cartilage repair responses in mature cartilage as observed in immature, developing cartilage.

Association between biochemical cartilage markers and clinical symptoms in patients with hip osteoarthritis: cohort study with 2-year follow-up

OBJECTIVESnTo assess associations between uCTX-II or uCIIM and severity of hip pain in patients with mild-moderate hip osteoarthritis (OA) over a 2-year period, and establish whether the level of these biomarkers at baseline could estimate a specific trajectory of hip pain.nnnDESIGNnA cohort study with a 2-year follow-up and 6-monthly measurements of urinary biomarkers (uCTX-II and uCIIM) and symptom severity. Patients were recruited from general practices. The primary outcome was hip pain, measured with the Western Ontario and McMasters University Osteoarthritis Index (WOMAC) subscale and the Visual Analog Scale (VAS). Associations between hip pain and biomarkers were assessed using linear mixed-model analysis for repeated measurements. Five previously identified pain trajectories were used as outcome to investigate whether the level of biomarkers at baseline could estimate membership in one of the trajectories using multinomial regression analysis.nnnRESULTSnLoguCTX-II and loguCIIM were not associated with WOMAC pain or VAS pain during the 2-year follow-up. Patients in the highly progressive pain trajectory and the moderate pain trajectory were more likely to have a higher loguCTX-II at baseline (OR 6.7; 95% CI 1.6-28.2 and OR 4.8; 95% CI 1.0-22.8, respectively) than patients in the mild pain trajectory.nnnCONCLUSIONnThis study shows that in patients with mild-moderate hip OA the urinary biochemical markers uCTX-II and uCIIM are not cross-sectionally associated with hip pain during the 2-year follow-up. Because the uCTX-II level estimated a progressive or moderate hip pain trajectory, this correlation needs to be confirmed in additional patients with hip OA.

Long-term Intra-articular Steroid Injections and Knee Cartilage

Author Contributions: Drs Sandin and Kuja-Halkola had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Concept and design: All authors. Acquisition, analysis, or interpretation of data: All authors. Drafting of the manuscript: Sandin, Hultman, Reichenberg. Critical revision of the manuscript for important intellectual content: All authors. Statistical analysis: Sandin, Kuja-Halkola. Obtained funding: Lichtenstein, Hultman, Larsson, Reichenberg. Administrative, technical, or material support: Lichtenstein, Hultman. Supervision: Hultman, Larsson, Reichenberg.

Diagnostic value of intra-articular anaesthetic hip joint injection in patients with atypical hip pain: a systematic review

s / Osteoarthritis and Cartilage 21 (2013) S63–S312 S135 specifically in the mesenchyme of developing limb buds as early as embryonic day 9.5. These mice were then crossed to mice with conditional (floxed) alleles of the Gsk3b gene, resulting in knockout (KO) GSK-3b specifically in the limb buds. These KO mouse mutants were then compared to their control littermates to examine any physical and molecular differences through whole skeletal preparations, immunohistochemistry on tissue sections, and a variety of other techniques. In addition to my in vivo studies, I will perform in vitro micromass cultures utilizing both an adenoviral delivery of Cre recombinase (with adenovirus-GFP as control) and pharmacological inhibitor to inactivate GSK-3. The in vitro studies will allow for further investigations into the molecular mechanisms associated with GSK-3 function in limb development, with a focus on the canonical Wnt/bcatenin pathway. C. Results: My preliminary analyses of the first mutants I obtained indeed suggest that their limbs are shorter, with a noted difference in digit length. Tissue sections of different long bones show a slight difference within the growth plate between the mutant mice and their control littermates. The in vitro micromasses cultures stained with alcian blue, which represents glycosaminoglycans in cartilage, show an increase in alcian blue stain with increasing concentration of the GSK-3 inhibitor SB86. Real-time PCR data of day 3 micromasses treated with SB86 indicates that there is a decrease in Aggrecan, Col2a1, and Sox9 markers, while Col1a1 remains relatively stable. Preliminary western blots show an increase in b-catenin accumulation within the micromasses treated with increasing concentrations of SB86. D. Conclusions: Together, these studies will provide insights into the mechanisms controlling limb development. Previous studies indicate that disruption of theWnt pathway, as we expect to occur in our model, causes limb malformations including brachydactyly and syndactyly, which are clinically important birth defects in humans. Our studies are therefore highly relevant to these birth defects, as well as adult skeletal diseases such as osteoarthritis that show a clear connection to skeletal