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Summary Objective To contribute to clarify molecular mechanisms supporting senescence and de-differentiation of chondrocytes in chondrocyte pathologies such as osteoarthritis (OA). Specifically, we investigated the relationship between the nuclear lamina protein Lamin B1 and the negative regulator of chondrogenesis Slug transcription factor in osteoarthritic chondrocytes. Methods Lamin B1 and Slug proteins were analyzed in cartilage explants from normal subjects and OA patients by immunohistochemical technique. Their expression was confirmed on isolated chondrocytes both at passage 0 and passage 2 (de-differentiated chondrocytes) by immunofluorescence and western blot. Subsequently, we explored the “ in vivo ” binding of Slug on LMNB1 promoter by chromatin immunoprecipitation assay (ChIP). Results In this study we demonstrated that nuclear lamina protein Lamin B1 and anti-chondrogenic Slug transcription factor are upregulated in cartilage and OA chondrocytes. Furthermore, we found that Slug is “ in vivo ” recruited by LMNB1 gene promoter mostly when chondrocytes undergo de-differentiation or OA degeneration. Conclusions We described for the first time a potential regulatory role of Slug on the LMNB1 gene expression in OA chondrocytes. These findings may have important implications for the study of premature senescence, and degeneration of cartilage, and may contribute to develop effective therapeutic strategies against signals supporting cartilage damage in different subsets of patients. [ABSTRACT FROM AUTHOR]

Total talar extrusion with no remaining soft tissue attachments is an extremely rare injury that may occur as a result of a high-energy extreme supination and plantar flexion forces causing an anterolateral dislocation. Due to the extreme rarity of such cases, few reports can be found in literature and the ideal treatment has not been determined. [ABSTRACT FROM AUTHOR]

The present study compares the in vitro effect of (±)-2'-deoxy-3'-thiacytidine (BCH 189) a new synthetic anti-HIV-1 dideoxynucleoside, with 3'-azido-3'-deoxythymidine (AZT) on the immune function of lymphocytes from 10 normal and 12 HIV-1+ patients (CDC II and III). The effect of different doses of BCH 189 and AZT was analysed in vitro on: (i) T cell proliferation after stimulation with concanavalin A (Con A) or anti-CD3 MoAb; (ii) B cell proliferation and immunoglobulin production after stimulation with pokeweed mitogen (PWM); (iii)cytokine production (IL-2, IL-6, GM-CSF, tumour necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ)) from lymphocytes stimulated with anti-CD3 MoAb or phytohaemagglutinin (PHA). BCH 189 inhibited the proliferation of B and T lymphocytes from normal and HIV+ subjects less than AZT; even if lymphocytes from HIV+ (CDC III) subjects produced higher levels of IL-6 and TNF-α, neither BCH 189 nor AZT molecule interfered with cytokine release. Immunoglobulin production from B lymphocytes was inhibited only by a high concentration (50 μM) of BCH 189 or AZT. These results show that BCII 189 affects lymphocyte proliferation in vitro less then AZT, and support its use in clinical trials in HIV-infected patients. [ABSTRACT FROM AUTHOR]

The article presents a study conducted to examine tumoral features in multiple myeloma patients. It observes that the multiple myeloma patients both bone osteoblastic (OBs) and mesenchymal stromal cells (MSCs) lacks features of tumornal. It also states that transcriptional alterations of MSCs and OBs do not depend on primary karyotype or telomerase alterations in patients with multiple myeloma.

Osteoarthritis (OA) is the most prevalent joint disorder causing pain and disability predominantly in the ageing population but also in young individuals. Current treatments are limited to alleviate symptoms, e.g. with anti-inflammatory drugs, until at the end stage of the disease the degenerated joint is replaced by a prosthetic implant. In this study we hypothesize that degenerative cartilage defects can be treated using Nasal chondrocyte-based Tissue Engineered Cartilage (N-TEC), as previously applied for the repair of focal articular cartilage lesions. In particular, we tested (i) the response of N-TECs to inflammatory factors, (ii) their capacity to modulate the inflammatory profile of OA joint cells in vitro as well as (iii) their survival in - and integration with OA tissues in vivo. Based on these results we then (iv) assessed the performance of N-TEC upon implantation in OA knee cartilage lesions of human patients. When N-TEC was exposed in vitro to inflammatory stimuli, as those found in OA joints (IL-1β/TNFα/IL-6 cytokines or factors secreted by OA synoviocytes) we demonstrate that it maintained its cartilaginous properties (i). Moreover, the secretome of N-TEC positively influenced the inflammatory profile of cells from OA joints, i.a. by reducing the expression of IL-6 and TNFα (ii). In vivo in an ectopic mouse model reproducing a human osteochondral OA tissue environment as well as in chronified articular cartilage defects in sheep, we further demonstrated cell survival and engraftment of N-TEC with the surrounding OA tissues (iii). Finally, we tested clinically the implantation of autologous N-TEC in two patients with advanced OA (Kellgren and Lawrence grade 3 and 4), who were otherwise considered for unicondylar knee arthroplasty. Patients reported reduced pain as well as improved joint function and life quality 14 months after surgery. In addition, a radiologically observed increase in joint space, indicating safety and feasibility of the treatment (iv). Together, our findings indicate that N-TEC can directly contribute to cartilage repair in OA joints. A phase II clinical trial is now required to assess efficacy in a larger cohort of OA patients. [ABSTRACT FROM AUTHOR]

Adipose mesenchymal stromal cells (ASC) are commonly utilized in various cell therapies and recently in phase I clinical trials to counteract the development of knee osteoarthritis. Administered-ASC in the knee joints enter in close contact with the OA inflammatory milieu and hypoxic environment,which could modulate their characteristics.Little is known about the OA milieu factors that could enhance the migration and tissue specific engraftment of exogenously injected ASC for successful regenerative cell therapy.Therefore,we tested the effect of OA milieu on good manufactured practice (GMP)-ASC,both in normoxic and hypoxic conditions and evaluated their migration properties and cytokine receptors. We analyzed IL8, IP10,SDF-1,MCP1,MIP1α, MIP1β,RANTES and IL6 cytokines in two different OA milieu:OA synovial fluid (SF) and OA-conditioned medium (CM) from synoviocytes.These milieu adequately represent the OA environment for ASC injection and the milieu containing all the soluble factors released by the target tissue of ASC, respectively. The same cytokines were analyzed also on basal GMP-ASC,both in normoxic and hypoxic conditions. Afterwards, GMP-ASC were treated either with OA-SF or OA-CM for 48hours and tested for migration and cytokine receptors expression, as well as the cytokine secretion, both in normoxia or hypoxia (1,5%O 2). Healthy SF was used as control. In OA-SF we detected higher amount of IP10 than in OA-CM while MCP1 and MIP1β were higher in OA-CM compared to OA-SF.All the other cytokines were detected in the same amounts in both OA milieu. We demonstrated that GMP-ASC show an increase in proliferation, migration, no changes in the amount of cytokines released and modulation of CXCR1,CXCR3,CCR1 and CCR5 receptors in hypoxic condition. Moreover,GMP-ASC migration increased 15-fold when treated either with OA-SF or OA-CM compared to healthy SF,both in normoxic and hypoxic conditions.GMP-ASC treated in OA milieu showed an increase of CXCR3, CCR3 and IL6R and a decrease of CCR1,CCR2 receptors. IP10 was the only chemokine of the OA milieu down-modulated after treatment with GMP-ASC.We demonstrated specific effects of OA milieu on both GMP-ASC migration and cytokine receptor expression that were strictly dependent by the inflammatory and hypoxic environment.The use of characterized OA milieu might contributes to define the therapeutic effects of GMP-ASC and indicates that IP10-CXCR3 axis is partially involved in GMP-ASC effect on synovial macrophages. [ABSTRACT FROM AUTHOR]