Increased Wnt5a/ROR2 signaling is associated with chondrogenesis in meniscal degeneration.

The aim of the present study was to investigate the association between chondrogenic differentiation and Wnt signal expression in the degenerative process of the human meniscus. Menisci were obtained from patients with and without knee osteoarthritis (OA), and degeneration was histologically assessed using a grading system. Immunohistochemistry, real-time polymerase chain reaction (PCR), and Western blot analysis were performed to examine the expressions of chondrogenic markers and of the components of Wnt signaling. Histological analyses showed that meniscal degeneration involved a transition from a fibroblastic to a chondrogenic phenotype with the upregulation of SOX9, collagen type II, collagen type XI, and aggrecan, which were associated with increased Wnt5a and ROR2 and decreased TCF7 expressions. OA menisci showed significantly higher expressions of Wnt5a and ROR2 and significantly lower expressions of AXIN2 and TCF7 than non-OA menisci on real-time PCR and Western blot analysis. These results potentially demonstrated that increased expression of Wnt5a/ROR2 signaling promoted chondrogenesis with decreased expression in downstream Wnt/ß-catenin signaling. This study provides insights into the role of Wnt signaling in the process of meniscal degeneration, shifting to a chondrogenic phenotype. The findings suggested that the increased expression of Wnt5a/ROR2 and decreased expression of the downstream target of Wnt/ß-catenin signaling are associated with chondrogenesis in meniscal degeneration.

Bevacizumab promotes tenogenic differentiation and maturation of rat tendon-derived cells in vitro.

Previous work suggested that tenogenic differentiation of tendon stem/progenitor cells (TSPCs) was suppressed by upregulated expression of the angiogenic marker vascular endothelial growth factor (VEGF). The purpose of this study was to test the hypothesis that anti-VEGF antibody, bevacizumab, promotes in vitro tenogenic differentiation and maturation of two distinct types of TSPCs, tendon proper-derived cells (TDCs), and paratenon-derived cells (PDCs) originating from rat Achilles tendon. TDCs and PDCs were isolated from the tendon proper and the paratenon of rat Achilles tendons. TDCs and PDCs were cultured for 3 days on plates with or without VEGF. TDCs and PDCs were also cultured in collagen gel matrix, and the blocking effect of VEGF was examined by the addition of 100 ng/mL of bevacizumab. Effects of bevacizumab on tenogenic differentiation were assessed using real-time PCR, immunofluorescent staining, and western blotting. VEGF significantly attenuated expression of the Tnmd gene in both PDCs and TDCs (P<0.05). Expressions of the Scx, Tnmd, and Col1a1 genes were significantly upregulated by the addition of bevacizumab (P<0.05). Immunofluorescent staining showed that the percentage of tenomodulin-positive PDCs and TDCs was significantly higher with bevacizumab treatment than in control cultures (P<0.05). Western blotting showed that bevacizumab suppressed pVEGFR-2 protein expression in both PDCs and TDCs. Bevacizumab promoted the in vitro tenogenic differentiation and maturation of two distinct TSPCs derived from rat Achilles tendon. Since the previous studies demonstrated that TSPCs have a potential to contribute to tendon repair, attenuating VEGF levels in TSPCs by administration of bevacizumab is a novel candidate therapeutic option for promoting tendon repair.

Bevacizumab suppressed degenerative changes in articular cartilage explants from patients with osteoarthritis of the knee.

BACKGROUND: This study was designed to test the hypothesis that blockade of vascular endothelial growth factor (VEGF) suppresses degenerative changes in articular cartilage from patients with osteoarthritis (OA). METHODS: Articular cartilage from eight OA patients was subjected to explant culture for 2 days in the presence or absence of 10 ng/ml recombinant interleukin (IL)-1ß. The blocking effect of VEGF was examined by the addition of 10 or 100 ng/ml of bevacizumab. The culture media were harvested, and markers for cartilage degradation were measured by sandwich enzyme-linked immunoassay. Total RNA was isolated from cartilage tissues, and gene expressions associated with the anabolic response were examined by the quantitative real-time polymerase chain reaction. RESULTS: Bevacizumab significantly reduced concentrations of matrix metalloproteinase (MMP)-2, MMP-3, and cartilage oligomeric matrix protein in the culture media with and without IL-1ß. Significant suppressive effects of bevacizumab on MMP-9 and MMP-13 were shown only in the presence of IL-1ß. Gene expression of Col2a1 was significantly increased by the addition of bevacizumab in the absence of IL-1ß. CONCLUSION: Bevacizumab inhibits catabolic reactions and stimulates anabolic function in articular cartilage derived from OA patients directly, suggesting a protective effect on articular cartilage from OA progression.

Genetic polymorphisms of killer cell immunoglobulin-like receptors are associated with susceptibility to psoriasis vulgaris.

To elucidate the association between killer cell immunoglobulin-like receptors (KIRs) and psoriasis vulgaris (PV), we typed 14 KIR genes in 96 Japanese cases and 50 healthy controls using PCR with sequence-specific primers (PCR-SSP). Here we report an interesting association between certain KIRs and Japanese cases with PV. The frequencies of KIR2DS1 and KIR2DL5 were significantly increased in PV cases compared with controls (KIR2DS1, 43 of 96 (45%) in cases vs 14 of 50 (28%) in controls; KIR2DL5, 46 of 96 (48%) in cases vs 15 of 50 (30%) in controls, p<0.05 for both), and the frequency of carriage of at least one presumed "B" haplotype, inferred from patterns including KIR2DL2, KIR2DL5, and/or various combinations of activating KIRs, was also statistically increased in the PV cases (53 of 96 (55%) in cases vs 18 of 50 (36%) in controls, p<0.04). The increase in KIR2DS1 has also been observed in psoriatic arthritis, another HLA-Cw6-associated disease (Martin et al, 2002). Accordingly, KIR2DS1 may be a common denominator of both diseases.