Ex vivo osteochondral test system with control over cartilage defect depth – A pilot study to investigate the effect of oxygen tension and chondrocyte based treatments in chondral and full thickness defects in an organ model

Objective Cartilage defect treatment strategies are dependent on the lesion size and severity. Osteochondral explant models are a platform to test cartilage repair strategies ex vivo. Current models lack in mimicking the variety of clinically relevant defect scenarios. In this controlled laboratory study, an automated device (artificial tissue cutter, ARTcut®) was implemented to reproducibly create cartilage defects with controlled depth. In a pilot study, the effect of cartilage defect depth and oxygen tension on cartilage repair was investigated. Design Osteochondral explants were isolated from porcine condyles. 4 ​mm chondral and full thickness defects were treated with either porcine chondrocytes (CHON) or co-culture of 20% CHON and 80% MSCs (MIX) embedded in collagen hydrogel. Explants were cultured with tissue specific media (without TGF-β) under normoxia (20% O$_2$) and physiological hypoxia (2% O$_2$). After 28 days, immune-histological stainings (collagen II and X, aggrecan) were scored (modified Bern score, 3 independent scorer) to quantitatively compare treatment outcome. Results ARTcut® represents a software-controlled device for creation of uniform cartilage defects. Comparing the scoring results of the MIX and the CHON treatment, a positive relation between oxygen tension and defect depth was observed. Low oxygen tension stimulated cartilaginous matrix deposition in MIX group in chondral defects and CHON treatment in full thickness defects. Conclusion ARTcut® has proved a powerful tool to create cartilage defects and thus opens a wide range of novel applications of the osteochondral model, including the relation between oxygen tension and defect depth on cartilage repair

Expandierte Zellen, Knochenmark, Fettgewebe: Was ist in Deutschland und Österreich erlaubt?

The options for articular cartilage therapy have been enriched in recent years by the use of concentrated bone marrow and adipose tissue aspirates as well as culture-expanded cells. Especially single step procedures with sampling of bone marrow or adipose tissue aspirates with intraoperative fabrication of cell concentrates seem to be attractive and are aggressively advertised by various manufactures as unproblematic point of care (PoC) procedures; however, by the use of such systems the surgeon effectively becomes the manufacturer of a drug within the statutory framework of the German Medicines Act (AMG). It is compulsory to notify the authorities about the usage, who then classify the procedure according to the method of processing (substantial or non-substantial) and application (homologous or nonhomologous). As cell products classified as advanced therapy medicinal products (ATMP), they require permission for sampling and manufacturing, which can only be gained in cooperation with the competent authorities (e.g. Paul Ehrlich Institute, state authorities). In this context the regulatory framework for the application of intraoperatively harvested bone marrow and adipose tissue aspirates as well as expanded cells for the treatment of articular cartilage diseases in Germany and Austria are discussed

From Single Batch to Mass Production–Automated Platform Design Concept for a Phase II Clinical Trial Tissue Engineered Cartilage Product

Advanced Therapy Medicinal Products (ATMP) provide promising treatment options particularly for unmet clinical needs, such as progressive and chronic diseases where currently no satisfying treatment exists. Especially from the ATMP subclass of Tissue Engineered Products (TEPs), only a few have yet been translated from an academic setting to clinic and beyond. A reason for low numbers of TEPs in current clinical trials and one main key hurdle for TEPs is the cost and labor-intensive manufacturing process. Manual production steps require experienced personnel, are challenging to standardize and to scale up. Automated manufacturing has the potential to overcome these challenges, toward an increasing cost-effectiveness. One major obstacle for automation is the control and risk prevention of cross contaminations, especially when handling parallel production lines of different patient material. These critical steps necessitate validated effective and efficient cleaning procedures in an automated system. In this perspective, possible technologies, concepts and solutions to existing ATMP manufacturing hurdles are discussed on the example of a late clinical phase II trial TEP. In compliance to Good Manufacturing Practice (GMP) guidelines, we propose a dual arm robot based isolator approach. Our novel concept enables complete process automation for adherent cell culture, and the translation of all manual process steps with standard laboratory equipment. Moreover, we discuss novel solutions for automated cleaning, without the need for human intervention. Consequently, our automation concept offers the unique chance to scale up production while becoming more cost-effective, which will ultimately increase TEP availability to a broader number of patients

Validation of microbiological testing of cellular medicinal products containing antibiotics

Background: The risk of microbial contamination of cellular products can be reduced when cultured in the presence of antibiotics. This however, may impact the sensitivity of microbiological tests. Given that the addition of antibiotics to cell/tissue products does not guarantee sterility but may just reduce the proliferation rate of microorganisms, microbiological testing of medicinal products remains obligatory. Thus, an appropriate method to test for microbial contamination of antibiotic-containing products has to be validated. Objectives: In the context of microbiological testing of a cellular advance therapy medicinal product, the method was validated and approved by German competent authorities for four different matrices with three matrices containing antibiotics. The paper shall provide help for establishing test methods for other investigational medicinal products which contain antibiotics. Methods: Matrices were spiked individually with Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Streptococcus pyogenes, Escherichia coli, Clostridium sporogenes, Propionibacterium acnes, Candida albicans, and Aspergillus brasiliensis. Samples were pretreated with penicillinase for 1 h before inoculation and incubation in BacT/ALERT iFA Plus and iFN Plus culture bottles using 3D BacT/ALERT automates. Microorganisms within positive BacT/ALERT bottles were specified. The procedure was performed in two different laboratories to prove robustness of test. Results: All nine tested microorganisms were detected within 14 days of incubation in accordance with requirements of the European Pharmacopoiea in terms of sensitivity, specificity and robustness of the test. Penicillin and streptomycin did not have any influence on specifications defined within the investigational medicinal product dossier. Conclusions: Culturing cellular products in the presence of antibiotics can serve as an effective method to reduce contamination risk but only if the chosen antibiotics neither have any influence on specifications of the investigational medicinal product nor interfere with microbiological tests. Consequently, cells and tissues primarily contaminated with microorganisms, like placenta, may be considered as a source of cellular therapeutics when cultured for a sufficient time with antibiotics and tested with a validated method. The choice of microorganisms for the validation of the microbiological test should always consider all conceivable scenarios and should not be reduced to minimal criteria defined in European Pharmacopoiea, wrongfully believing to thus save time and effort. © In Copyright http://rightsstatements.org/vocab/InC/1.0

Regulatory-Compliant Validation of a Highly Sensitive qPCR for Biodistribution Assessment of Hemophilia A Patient Cells

The investigation of the biodistribution profile of a cell-based medicinal product is a pivotal prerequisite to allow a factual benefit-risk assessment within the non-clinical to clinical translation in product development. Here, a qPCR-based method to determine the amount of human DNA in mouse DNA was validated according to the guidelines of the European Medicines Agency and the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. Furthermore, a preclinical worst-case scenario study was performed in which this method was applied to investigate the biodistribution of 2 x 10$^6$ intravenously administered, genetically modified, blood outgrowth endothelial cells from hemophilia A patients after 24 h and 7 days. The validation of the qPCR method demonstrated high accuracy, precision, and linearity for the concentration interval of 1:1 x 10$^3$ to 1:1 x 10$^6$ human to mouse DNA. The application of this method in the biodistribution study resulted in the detection of human genomes in four out of the eight investigated organs after 24 h. After 7 days, no human DNA was detected in the eight organs analyzed. This biodistribution study provides mandatory data on the toxicokinetic safety profile of an actual candidate cell-based medicinal product. The extensive evaluation of the required validation parameters confirms the applicability of the qPCR method for non-clinical biodistribution studies

Injection of Adipose-Derived Stromal Cells in the Knee of Patients with Severe Osteoarthritis has a Systemic Effect and Promotes an Anti-Inflammatory Phenotype of Circulating Immune Cells

International audienceRationale: Recent studies confirmed that osteoarthritis (OA) is associated with systemic inflammation. Adipose-derived stromal cells (ASCs) could become the most promising cell-based therapy in OA, based not only on their differentiation capacities and trophic and paracrine effects on the existing cartilage, but also on their immunomodulatory properties. Here, we wanted to determine the biological effect of autologous ASC intra-articular (IA) injection. Method: To this aim, we monitored the profile of immune cells in fresh peripheral blood after IA injection of autologous ASCs in the knee of 18 patients with severe OA (ADIPOA phase I study). Specifically, we used 8-color flow cytometry antibody panels to characterize the frequencies of innate and adaptive immune cell subsets (monocytes, dendritic cells, regulatory T cells and B cells) in blood samples at baseline (before injection) and one week, one month and three months after ASC injection. Results: We found that the percentage of CD4+CD25highCD127lowFOXP3+ regulatory T cells was significantly increased at 1 month after ASC injection, and this effect persisted for at least 3 months. Moreover, CD24highCD38high transitional B cells also were increased, whereas the percentage of classical CD14+ monocytes was decreased, at 3 months after ASC injection. These results suggest a global switch toward regulatory immune cells following IA injection of ASCs, underscoring the safety of ASC-based therapy. We did not find any correlation between the scores for the Visual Analogic Scale for pain, the Western Ontario and McMaster Universities Osteoarthritis Index (pain subscale and total score) at baseline and the immune cell profile changes, but this could be due to the small number of analyzed patients. Conclusion: ASCs may drive an immediate local response by releasing paracrine factors and cytokines, and our results suggest that ASCs could also initiate a cascade resulting in a long-lasting systemic immune modulation

Adipose Mesenchymal Stromal Cell-Based Therapy for Severe Osteoarthritis of the Knee: A Phase I Dose-Escalation Trial

International audienceOsteoarthritis x Adipose mesenchymal stromal cells x Intra-articular injection x Therapeutic potential x Regenerative medicine x Phase I clinical trial ABSTRACT Osteoarthritis (OA) is the most widespread musculoskeletal disorder in adults. It leads to cartilage damage associated with subchondral bone changes and synovial inflammation, causing pain and disability. The present study aimed at evaluating the safety of a dose-escalation protocol of intra-articular injected adipose-derived stromal cells (ASCs) in patients with knee OA, as well as clinical efficacy as secondary endpoint. A bicentric, uncontrolled, open phase I clinical trial was conducted in France and Germany with regulatory agency approval for ASC expansion procedure in both countries. From April 2012 to December 2013, 18 consecutive patients with symptomatic and severe knee OA were treated with a single intra-articular injection of autologous ASCs. The study design consisted of three consecutive cohorts (six patients each) with dose escalation: low dose (2 3 10 6 cells), medium dose (10 3 10 6), and high dose (50 3 10 6). The primary outcome parameter was safety evaluated by recording adverse events throughout the trial, and secondary parameters were pain and function subscales of the Western Ontario and McMaster Universities Arthritis Index. After 6 months of follow-up, the procedure was found to be safe, and no serious adverse events were reported. Four patients experienced transient knee joint pain and swelling after local injection. Interestingly, patients treated with low-dose ASCs experienced significant improvements in pain levels and function compared with baseline. Our data suggest that the intraarticular injection of ASCs is a safe therapeutic alternative to treat severe knee OA patients. A placebo-controlled double-blind phase IIb study is being initiated to assess clinical and structural efficacy

Trademark dilution and its practical effect on purchase decision

This work aims to analyze the effect of unauthorized use of trademarks on its consumer-based brand equity and on the consumer purchase decision, through a mediation model with structural equations. An experiment was carried out with 618 participants, who were exposed to advertising of famous brand products or senior brands, and fictitious products with the same brands or junior brands. Participants were then asked to make some purchases with a real budget of US$5. The results show that exposure to junior brands reduces senior brand equity, i.e. results in trademark dilution, mediating a reduction in the purchase of senior brand products. In addition, similarity between junior and senior brands alleviates brand equity dilution, while consumer involvement with the product category of the famous brand has no moderating effect. The study aims to contribute to our understanding of trademark dilution, including the effect on purchase decision – a subject so far unexplored in the empirical literature. Moreover, the study pursues to highlight the importance of protecting well-known trademarks in order to avoid damage occurring not only in consumer perceptions, but also in firm's sales and brand financial value.Este trabajo analiza el efecto del uso no autorizado de marcas registradas sobre su capital de marca y la decisión de compra de sus consumidores, mediante un modelo de ecuaciones estructurales. Se diseñó un experimento en donde 618 participantes fueron expuestos a publicidad de productos de marcas famosas (marcas senior) o de productos ficticios con las mismas marcas (marcas junior), y luego realizaron compras con un presupuesto real de US$ 5. Los resultados muestran que la exposición a las marcas junior reduce el capital de marca de las marcas senior (dilución), funcionando como efecto mediador en la reducción de la compra de sus productos. Se encontró que a mayor similitud entre la marca junior y la senior, se reduce la dilución del capital de marca de esta última, mientras que el nivel de involucramiento con la categoría de producto de las marcas senior no tuvo un efecto moderador. El estudio contribuye al conocimiento de la dilución de marcas registradas, llegando hasta el efecto -aún no estudiado- sobre la decisión de compra, y pone de manifiesto la importancia de la protección de las marcas famosas o renombradas, con el objeto de evitar daños no sólo en las percepciones del consumidor, sino también en las ventas y el valor financiero de la marca