A GMP-compliant manufacturing method for Wharton's jelly-derived mesenchymal stromal cells

BACKGROUND

Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) hold great therapeutic potential in regenerative medicine. Therefore, it is crucial to establish a Good Manufacturing Practice (GMP)-compliant methodology for the isolation and culture of WJ-MSCs. Through comprehensive research, encompassing laboratory-scale experiments to pilot-scale studies, we aimed to develop standardized protocols ensuring the high yield and quality of WJ-MSCs manufacturing.

METHODS

Firstly, optimization of parameters for the enzymatic digestion method used to isolate WJ-MSCs was conducted. These parameters included enzyme concentrations, digestion times, seeding densities, and culture media. Additionally, a comparative analysis between the explant method and the enzymatic digestion method was performed. Subsequently, the consecutive passaging of WJ-MSCs, specifically up to passage 9, was evaluated using the optimized method. Finally, manufacturing processes were developed and scaled up, starting from laboratory-scale flask-based production and progressing to pilot-scale cell factory-based production. Furthermore, a stability study was carried out to assess the storage and use of drug products (DPs).

RESULTS

The optimal parameters for the enzymatic digestion method were a concentration of 0.4 PZ U/mL Collagenase NB6 and a digestion time of 3 h, resulting in a higher yield of P0 WJ-MSCs. In addition, a positive correlation between the weight of umbilical cord tissue and the quantities of P0 WJ-MSCs has been observed. Evaluation of different concentrations of human platelet lysate revealed that 2% and 5% concentrations resulted in similar levels of cell expansion. Comparative analysis revealed that the enzymatic digestion method exhibited faster outgrowth of WJ-MSCs compared to the explant method during the initial passage. Passages 2 to 5 exhibited higher viability and proliferation ability throughout consecutive passaging. Moreover, scalable manufacturing processes from the laboratory scale to the pilot scale were successfully developed, ensuring the production of high-quality WJ-MSCs. Multiple freeze-thaw cycles of the DPs led to reduced cell viability and viable cell concentration. Subsequent thawing and dilution of the DPs resulted in a significant decrease in both metrics, especially when stored at 20-27 °C.

CONCLUSION

This study offers valuable insights into optimizing the isolation and culture of WJ-MSCs. Our scalable manufacturing processes facilitate the large-scale production of high-quality WJ-MSCs. These findings contribute to the advancement of WJ-MSCs-based therapies in regenerative medicine.

Good manufacturing practices production of human placental derived mesenchymal stem cells for therapeutic applications: focus on multiple sclerosis

BACKGROUND

Among neurological diseases, multiple sclerosis (MS) affects mostly young adults and can cause long-term disability. While most medications with approval from regulatory agencies are very effective in treating MS disease, they are unable to repair the tissue damage found in the central nervous system (CNS). Consequently, Cell-based therapy particularly using mesenchymal stem/stromal cells (MSCs), holds promise for neuroprotection and tissue repair in MS treatment. Furthermore, placenta-derived MSCs (PLMSCs) have shown the potential to treat MS due to their abundance, noninvasive isolation from discarded tissues, no ethical problems, anti-inflammatory, and reparative properties. Accordingly, good manufacturing practices (GMPs) plays a crucial part in clinical SCs manufacturing. The purpose of our article is to discuss GMP-grade PLMSC protocols for treating MS as well as other clinical applications.

METHODS AND RESULTS

Placental tissue obtained of a healthy donor during the caesarean delivery and PLMSCs isolated by GMP standards. Flow cytometry was used to assess the expression of the CD markers CD34, CD105, CD90, and CD73 in the MSCs and the mesodermal differentiation ability was evaluated. Furthermore, Genetic evaluation of PLMSCs was done by G-banded karyotyping and revealed no chromosomal instability. In spite of the anatomical origin of the starting material, PLMSCs using this method of culture were maternal in origin.

CONCLUSIONS

We hope that our protocol for clinical manufacturing of PLMSCs according to GMP standards will assist researchers in isolating MSCs from placental tissue for clinical and pre-clinical applications.

Understanding the Angiogenic Characteristics of Clinical-Grade Mesenchymal Stromal Cells Isolated from Human Umbilical Cord

Addressing the challenges in managing ischemic tissue repair and remodelling remains a prominent clinical concern. Current research is heavily concentrated on identifying innovative cell-based therapies with the potential to enhance revascularization in patients affected by these diseases. We have previously developed and validated a manufacturing process for human umbilical cord mesenchymal stromal cells (UC-MSCs)-based cell therapy medicinal product, according to Good Manufacturing Practices. In this study, we demonstrate that these UC-MSCs enhance the proliferation and migration of endothelial cells and the formation of capillary structures. Moreover, UC-MSCs and endothelial cells interact, allowing UC-MSCs to acquire a perivascular cell phenotype and consequently provide direct support to the newly formed vascular network. This characterization of the proangiogenic properties of this UC-MSCs based-cell therapy medicinal product is an essential step for its therapeutic assessment in the clinical context of vascular regeneration.

Creating an Assessment Indicator of Quality Culture Development in the Generic Pharmaceutical Industry in Japan

In the past few years, there have been several instances of illicit pharmaceutical manufacturing in Japan, and there is a growing awareness of the importance of corporate compliance and pharmaceutical manufacturing and quality controls. One cause of illicit manufacturing is the inadequate development of quality culture. This study focuses on the degree of quality culture development in Japanese pharmaceutical companies manufacturing generic drugs. Because no evaluation index for Japan can visualize the degree of quality culture development in each company, this study sought to establish this index to utilize it as a tool for evaluating the degree of quality culture development that would enable each company to continuously monitor and improve its own. We conducted a questionnaire survey among Japan Generic Medicines Association members to evaluate the degree of their quality culture development. The questionnaire contained 28 questions in five evaluation categories. Potential indicators of quality culture development included "Employee growth and satisfaction"; "Management commitment"; "Improvement activities"; "Communication"; and "Environment, health, and safety." We obtained 294 responses from 37 Marketing Authorization Holder (MAH) and 61 manufacturing sites. Respondents were classified by roles of management, manager, and nonmanager. The results confirmed the current status of quality culture development efforts, showing that important messages such as the corporate philosophy as communicated by the management is well known, awareness of quality culture development level differs by role, and appropriate resources are not adequately allocated to employees or facilities. Based on the results, use of the index of quality culture development helped to make relative comparisons and visualize the areas to be addressed for quality culture development. This study established and visualized the index for the degree of quality culture development in domestic generic drug manufacturing companies and we hope this indicator becomes a useful tool for evaluating a company's quality culture development level.

Good manufacturing practice production of human corneal limbus-derived stromal stem cells and in vitro quality screening for therapeutic inhibition of corneal scarring

BACKGROUND

Mesenchymal stem cells in the adult corneal stroma (named corneal stromal stem cells, CSSCs) inhibit corneal inflammation and scarring and restore corneal clarity in pre-clinical corneal injury models. This cell therapy could alleviate the heavy reliance on donor materials for corneal transplantation to treat corneal opacities. Herein, we established Good Manufacturing Practice (GMP) protocols for CSSC isolation, propagation, and cryostorage, and developed in vitro quality control (QC) metric for in vivo anti-scarring potency of CSSCs in treating corneal opacities.

METHODS

A total of 24 donor corneal rims with informed consent were used-18 were processed for the GMP optimization of CSSC culture and QC assay development, while CSSCs from the remaining 6 were raised under GMP-optimized conditions and used for QC validation. The cell viability, growth, substrate adhesion, stem cell phenotypes, and differentiation into stromal keratocytes were assayed by monitoring the electric impedance changes using xCELLigence real-time cell analyzer, quantitative PCR, and immunofluorescence. CSSC's conditioned media were tested for the anti-inflammatory activity using an osteoclastogenesis assay with mouse macrophage RAW264.7 cells. In vivo scar inhibitory outcomes were verified using a mouse model of anterior stromal injury caused by mechanical ablation using an Algerbrush burring.

RESULTS

By comparatively assessing various GMP-compliant reagents with the corresponding non-GMP research-grade chemicals used in the laboratory-based protocols, we finalized GMP protocols covering donor limbal stromal tissue processing, enzymatic digestion, primary CSSC culture, and cryopreservation. In establishing the in vitro QC metric, two parameters-stemness stability of ABCG2 and nestin and anti-inflammatory ability (rate of inflammation)-were factored into a novel formula to calculate a Scarring Index (SI) for each CSSC batch. Correlating with the in vivo scar inhibitory outcomes, the CSSC batches with SI < 10 had a predicted 50% scar reduction potency, whereas cells with SI > 10 were ineffective to inhibit scarring.

CONCLUSIONS

We established a full GMP-compliant protocol for donor CSSC cultivation, which is essential toward clinical-grade cell manufacturing. A novel in vitro QC-in vivo potency correlation was developed to predict the anti-scarring efficacy of donor CSSCs in treating corneal opacities. This method is applicable to other cell-based therapies and pharmacological treatments.

Quality management overview for the production of a tissue-engineered human skin substitute in Malaysia

Treatments for skin injuries have recently advanced tremendously. Such treatments include allogeneic and xenogeneic transplants and skin substitutes such as tissue-engineered skin, cultured cells, and stem cells. The aim of this paper is to discuss the general overview of the quality assurance and quality control implemented in the manufacturing of cell and tissue product, with emphasis on our experience in the manufacturing of MyDerm®, an autologous bilayered human skin substitute. Manufacturing MyDerm® requires multiple high-risk open manipulation steps, such as tissue processing, cell culture expansion, and skin construct formation. To ensure the safety and efficacy of this product, the good manufacturing practice (GMP) facility should establish a well-designed quality assurance and quality control (QA/QC) programme. Standard operating procedures (SOP) should be implemented to ensure that the manufacturing process is consistent and performed in a controlled manner. All starting materials, including tissue samples, culture media, reagents, and consumables must be verified and tested to confirm their safety, potency, and sterility. The final products should also undergo a QC testing series to guarantee product safety, efficacy, and overall quality. The aseptic techniques of cleanroom operators and the environmental conditions of the facility are also important, as they directly influence the manufacturing of good-quality products. Hence, personnel training and environmental monitoring are necessary to maintain GMP compliance. Furthermore, risk management implementation is another important aspect of QA/QC, as it is used to identify and determine the risk level and to perform risk assessments when necessary. Moreover, procedures for non-conformance reporting should be established to identify, investigate, and correct deviations that occur during manufacturing. This paper provides insight and an overview of the QA/QC aspect during MyDerm® manufacturing in a GMP-compliant facility in the Centre for Tissue Engineering and Regenerative Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia.

GMP-grade human neural progenitors delivered subretinally protect vision in rat model of retinal degeneration and survive in minipigs

BACKGROUND

Stem cell products are increasingly entering early stage clinical trials for treating retinal degeneration. The field is learning from experience about comparability of cells proposed for preclinical and clinical use. Without this, preclinical data supporting translation to a clinical study might not adequately reflect the performance of subsequent clinical-grade cells in patients.

METHODS

Research-grade human neural progenitor cells (hNPC) and clinical-grade hNPC (termed CNS10-NPC) were injected into the subretinal space of the Royal College of Surgeons (RCS) rat, a rodent model of retinal degeneration such as retinitis pigmentosa. An investigational new drug (IND)-enabling study with CNS10-NPC was performed in the same rodent model. Finally, surgical methodology for subretinal cell delivery in the clinic was optimized in a large animal model with Yucatan minipigs.

RESULTS

Both research-grade hNPC and clinical-grade hNPC can survive and provide functional and morphological protection in a dose-dependent fashion in RCS rats and the optimal cell dose was defined and used in IND-enabling studies. Grafted CNS10-NPC migrated from the injection site without differentiation into retinal cell phenotypes. Additionally, CNS10-NPC showed long-term survival, safety and efficacy in a good laboratory practice (GLP) toxicity and tumorigenicity study, with no observed cell overgrowth even at the maximum deliverable dose. Finally, using a large animal model with the Yucatan minipig, which has an eye size comparable to the human, we optimized the surgical methodology for subretinal cell delivery in the clinic.

CONCLUSIONS

These extensive studies supported an approved IND and the translation of CNS10-NPC to an ongoing Phase 1/2a clinical trial (NCT04284293) for the treatment of retinitis pigmentosa.

Fully closed and automated enrichment of primary blood dendritic cells for cancer immunotherapy

Dendritic cell (DC) vaccination is a promising approach to induce tumor-specific immune responses in cancer patients. Until recently, most DC vaccines were based on in vitro-differentiated monocyte-derived DCs. However, through development of efficient isolation techniques, the use of primary blood dendritic cell subsets has come within reach. Manufacturing of blood-derived DCs has multiple advances over monocytes-derived DCs, including more standardized isolation and culture protocols and shorter production processes. In peripheral blood, multiple DC subsets can be distinguished based on their phenotype and function. Plasmacytoid DC (pDC) and myeloid/conventional DCs (cDC) are the two main DC populations, moreover cDC can be further subdivided into CD141/BDCA3+ DC (cDC1) and CD1c/BDCA1+ DC (cDC2). In three separate clinical DC vaccination studies in melanoma and prostate cancer patients, we manufactured DC vaccines consisting of pDCs only, cDC2s only, or a combination of pDC and cDC2s, which we called natural DCs (nDC). Here, we describe a fully closed and automated GMP-compliant method to enrich naturally circulating DCs and present the results of enrichment of primary blood DCs from aphaeresis products of 8 healthy donors, 21 castrate-resistant prostate cancer patients, and 112 stage III melanoma patients. Although primary blood DCs are relatively scarce in aphaeresis material, our results show that it is feasible to isolate highly pure pDC, cDC2, or nDC with sufficient yield to manufacture DC vaccines for natural DC-based immunotherapy.

Quality Culture and Knowledge Management in the Japanese Pharmaceutical Industry-A Cross-Sectional Study and Case Report

In the past few years, there have been several instances of illicit pharmaceutical manufacturing in Japan. Insufficient good manufacturing practice compliance and lack of quality culture in some pharmaceutical companies have been suggested as the underlying reasons for such cases. We aimed to focus on knowledge management and fostering of quality culture in pharmaceutical companies in Japan to understand their current situation and find a strategy for the availability of high-quality reliable pharmaceutical products. A wide-ranging questionnaire survey was conducted to understand the issues related to knowledge management and fostering of quality culture across pharmaceutical companies in Japan. A published investigation report on an illicit manufacturing case was closely examined by organizing the available facts using the diagram. Based on 395 responses to the questionnaire survey, we found that although pharmaceutical companies understand the importance of knowledge management and quality culture, issues exist in their operational methods. A total of 94% of the respondents agreed that they mentioned "knowledge management" as an enabler of the Pharmaceutical Quality System of ICH Q10, and 98% of the respondents accepted that insufficient fostering of quality culture leads to corporate risk. However, the survey revealed that many companies are struggling with this approach. Based on a report on an illicit manufacturing case, we analyzed the direct causes of misconduct and prepared a systematic summary that can be easily comprehended. Comparison of the illicit manufacturing case report with our questionnaire results suggests that many pharmaceutical companies do not regard the misconduct case as a situation that could occur in their company. With the revision of the Pharmaceuticals and Medical Devices Act and good manufacturing practice Ministerial Ordinance, we advocate the need for all employees of pharmaceutical companies to reconsider the priorities of their companies from the patient perspective.

Generic Drug Shortage in Japan: GMP Noncompliance and Associated Quality Issues

Government campaigns to replace off-patent brand pharmaceuticals with low cost generic products in national health insurance systems have apparently increased their production in the last two decades in Japan. The contamination of a batch of generic itraconazole tablets with the sleep inducer rilmazafone caused significant adverse events and related accidents in 2020, amidst increasing use of the generic products in healthcare. Investigations revealed many Good Manufacturing Practice (GMP) violations and other evidence of poor quality management in the manufacturing/marketing authorization holder (MAH). Urgent inspection of other MAHs found multiple cases of GMP noncompliance that resulted in temporary administrative suspension. Various quality issues, including nonconformity in stability monitoring, in these generic MAHs resulted in prolonged suspension of product shipments and shortages in medical institutions. These problems highlighted long-standing issues in quality management by MAHs and inspections by authorities, which had been neglected during rapid production expansion. This review introduces these manufacturing control and management problems and their countermeasures, and discusses the impact of habitual inadequate development processes that disregard the quality-by-design (QbD) perspective as the root cause of the issues.

Human iPS Cells for Clinical Applications and Cellular Products

Human induced pluripotent stem cells (iPSCs), since their discovery in 2007, have rapidly become a starting cell type of choice for the differentiation of many mature cell types. Their flexibility, amenability to gene editing and functional equivalence to embryonic stem cells ensured their subsequent adoption by many manufacturing processes for cellular products. In this chapter, we will discuss the process whereby iPSCs are generated, key quality control steps which should be considered during manufacturing, the application of good manufacturing practice to production processes and iPSC-derived cellular products which are already undergoing clinical trials. iPSCs provide a new avenue for the next generation of cellular therapeutics and by combining new differentiation protocols, quality control and reproducible manufacturing, iPSC-derived cellular products could provide treatments for many currently untreatable diseases, allowing the large-scale manufacture of high-quality cell therapies.

Clinical grade manufacture of 3D printed patient specific biodegradable devices for pediatric airway support

Implantable patient-specific devices are the next frontier of personalized medicine, positioned to improve the quality of care across multiple clinical disciplines. Translation of patient-specific devices requires time- and cost-effective processes to design, verify and validate in adherence to FDA guidance for medical device manufacture. In this study, we present a generalized strategy for selective laser sintering (SLS) of patient-specific medical devices following the prescribed guidance for additive manufacturing of medical devices issued by the FDA in 2018. We contextualize this process for manufacturing an Airway Support Device, a life-saving tracheal and bronchial implant restoring airway patency for pediatric patients diagnosed with tracheobronchomalacia and exhibiting partial or complete airway collapse. The process covers image-based modeling, design inputs, design verification, material inputs and verification, device verification, and device validation, including clinical results. We demonstrate how design and material assessment lead to verified Airway Support Devices that achieve desired airway patency and reduction in required Positive End-Expiratory Pressure (PEEP) after patient implantation. We propose this process as a template for general quality control of patient-specific, 3D printed implants.

Advanced Therapy Medicinal Products and the Changing Role of Academia

Academic institutions coin the ATMP landscape but do not possess an industry-like capacity to vigorously pursue the full developmental pathway to marketing authorization. At the same time, industry has fostered clinical trials with ATMPs, brought the first products to marketing authorization, and defined novel modes of interaction with academia. A regulatory niche for local manufacturing of ATMPs within an academic institution had been foreseen in Regulation (EU) 1394/2007 under the term "Hospital Exemption" but remained ill-defined. Manufacture in close proximity to the patient is difficult to accomplish, as "point of care" systems for the manufacture of ATMPs have encountered regulatory challenges hovering between process and product. The efforts and costs for the development of ATMPs continue to be dramatically underestimated, and few academic centers were persistent enough to invest in the GMP infrastructure needed and to recruit personnel trained in ATMP development. As a consequence, the contribution by hospitals to ATMP development has shifted from the finished ATMP toward the procurement of starting materials, selected manufacturing steps, storage of the product, clinical application, and participation in clinical trials. As the development and use of cell-based therapies and ATMPs continue to attract and challenge clinicians and scientists, this review aims to discuss logistical, financial, and regulatory issues that might contribute to the changing role of Academia in ATMP development, with an outlook into possible developments in the future and proposals for ways to reshape the academic environment under the auspices of what might truly have been meant by the hospital exemption clause.

multi-patient dose synthesis of [18F]Flumazenil via a copper-mediated 18F-fluorination

Background

Flumazenil (FMZ) is a functionally silent imidazobenzodiazepine which binds to the benzodiazepine binding site of approximately 75% of the brain γ-aminobutyric acid-A receptors (GABA_ARs). Positron Emission Tomography (PET) imaging of the GABAARs with [¹¹C]FMZ has been used to evidence alterations in neuronal density, to assess target engagement of novel pharmacological agents, and to study disorders such as epilepsy and Huntington’s disease. Despite the potential of FMZ PET imaging the short half-life (t_1/2) of carbon-11 (20 min) has limited the more widespread clinical use of [¹¹C]FMZ. The fluorine-18 (¹⁸F) isotopologue with a longer t_1/2 (110 min) is ideally suited to address this drawback. However, the majority of current radiochemical methods for the synthesis of [¹⁸F]FMZ are non-trivial and low yielding. We report a robust, automated protocol that is good manufacturing practice (GMP) compatible, and yields multi-patient doses of [¹⁸F]FMZ.

Results

The fully automated synthesis was developed on the Trasis AllinOne (AIO) platform using a single-use cassette. [¹⁸F]FMZ was synthesized in a one-step procedure from [¹⁸F]fluoride, via a copper-mediated ¹⁸F-fluorination of a boronate ester precursor. Purification was performed by semi-preparative radio-HPLC and the collected fraction formulated directly into the final product vial. The overall process from start of synthesis to delivery of product is approximately 55 min. Starting with an initial activity of 23.6 ± 5.8 GBq (n = 3) activity yields of [¹⁸F]FMZ were 8.0 ± 1 GBq (n = 3). The synthesis was successfully reproduced at two independent sites, where the product passed quality control release criteria in line with the European Pharmacopoeia standards and ICH Q3D(R1) guidelines to be suitable for human use.

Conclusion

Reported is a fully automated cassette-based synthesis of [¹⁸F]FMZ that is Good Manufacturing Practice (GMP) compatible and produces multi-patient doses of [¹⁸F]FMZ.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41181-022-00158-z.

A Roadmap for the Production of a GMP-Compatible Cell Bank of Allogeneic Bone Marrow-Derived Clonal Mesenchymal Stromal Cells for Cell Therapy Applications

Background

Allogeneic mesenchymal stromal cells (MSCs) have been used extensively in various clinical trials. Nevertheless, there are concerns about their efficacy, attributed mainly to the heterogeneity of the applied populations. Therefore, producing a consistent population of MSCs is crucial to improve their therapeutic efficacy. This study presents a good manufacturing practice (GMP)-compatible and cost-effective protocol for manufacturing, banking, and lot-release of a homogeneous population of human bone marrow-derived clonal MSCs (cMSCs).

Methods

Here, cMSCs were isolated based on the subfractionation culturing method. Afterward, isolated clones that could reproduce up to passage three were stored as the seed stock. To select proliferative clones, we used an innovative, cost-effective screening strategy based on lengthy serial passaging. Finally, the selected clones re-cultured from the seed stock to establish the following four-tired cell banking system: initial, master, working, and end of product cell banks (ICB, MCB, WCB, and EoPCB).

Results

Through a rigorous screening strategy, three clones were selected from a total of 21 clones that were stored during the clonal isolation process. The selected clones met the identity, quality, and safety assessments criteria. The validated clones were stored in the four-tiered cell bank system under GMP conditions, and certificates of analysis were provided for the three-individual ready-to-release batches. Finally, a stability study validated the EoPCB, release, and transport process of the frozen final products.

Conclusion

Collectively, this study presents a technical and translational overview of a GMP-compatible cMSCs manufacturing technology that could lead to the development of similar products for potential therapeutic applications.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s12015-022-10351-x.

Modified mesenchymal stem cells in cancer therapy: A smart weapon requiring upgrades for wider clinical applications

Mesenchymal stem stromal cells (MSC) are characterized by the intriguing capacity to home toward cancer cells after systemic administration. Thus, MSC can be harnessed as targeted delivery vehicles of cytotoxic agents against tumors. In cancer patients, MSC based advanced cellular therapies were shown to be safe but their clinical efficacy was limited. Indeed, the amount of systemically infused MSC actually homing to human cancer masses is insufficient to reduce tumor growth. Moreover, induction of an unequivocal anticancer cytotoxic phenotype in expanded MSC is necessary to achieve significant therapeutic efficacy. Ex vivo cell modifications are, thus, required to improve anti-cancer properties of MSC. MSC based cellular therapy products must be handled in compliance with good manufacturing practice (GMP) guidelines. In the present review we include MSC-improving manipulation approaches that, even though actually tested at preclinical level, could be compatible with GMP guidelines. In particular, we describe possible approaches to improve MSC homing on cancer, including genetic engineering, membrane modification and cytokine priming. Similarly, we discuss appropriate modalities aimed at inducing a marked cytotoxic phenotype in expanded MSC by direct chemotherapeutic drug loading or by genetic methods. In conclusion, we suggest that, to configure MSC as a powerful weapon against cancer, combinations of clinical grade compatible modification protocols that are currently selected, should be introduced in the final product. Highly standardized cancer clinical trials are required to test the efficacy of ameliorated MSC based cell therapies.

Regulation of Molecular Farming Products

The regulation of molecular farming is a complex topic because plants and plant-based systems are relative newcomers among the many production platforms available for recombinant proteins. The regulations specific for different types of product (human/veterinary pharmaceuticals and medical devices, cosmetics, diagnostics, and research reagents) must therefore be overlaid with the regulations governing hitherto unfamiliar production platforms, and this must be achieved in different jurisdictions that handle genetically modified organisms (and genetically modified plants in particular) in very different ways. This chapter uses examples of different product types and production methods in three different jurisdictions (the USA, the EU, and Canada) to demonstrate some of the challenges facing the regulatory authorities.

Development of a human umbilical cord-derived mesenchymal stromal cell-based advanced therapy medicinal product to treat immune and/or inflammatory diseases

Background

Umbilical cord-derived mesenchymal stromal cells (UC-MSCs) revealed their key role in immune regulation, offering promising therapeutic perspectives for immune and inflammatory diseases. We aimed to develop a production process of an UC-MSC-based product and then to characterize UC-MSC properties and immunomodulatory activities in vitro, related to their clinical use and finally, to transfer this technology to a good manufacturing practice (GMP) compliant facility, to manufacture an advanced therapy medicinal product (ATMP).

Methods

Fifteen human umbilical cords (UCs) were collected to develop the production process. Three batches of UC-MSCs from a single donor were characterized at basal state and after in vitro pro-inflammatory stimulation by interferon-γ (IFNγ) and tumor necrosis factor-α (TNFα). Proliferation, immunophenotype, activation markers’ expression and the inhibition of T cell proliferation were assessed. Finally, this technology was transferred to a GMP-compliant facility to manufacture an UC-MSC-based ATMP, from a single donor, using the explant method followed by the establishment of master and work cell stocks.

Results

Twelve UCs were processed successfully allowing to isolate UC-MSCs with doubling time and population doubling remaining stable until passage 4. CD90, CD105, CD73, CD44, CD29, CD166 expression was positive; CD14, CD45, CD31, HLA-DR, CD40, CD80 and CD86 expression was negative, while CD146 and HLA-ABC expression was heterogeneous. Cell morphology, proliferation and immunophenotype were not modified by inflammatory treatment. Indoleamine 2,3-dioxygenase (IDO) expression was significantly induced by IFNγ and IFNγ + TNFα versus non-treated cells. Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) expression was induced significantly after priming. T cell proliferation was significantly decreased in the presence of UC-MSCs in a dose-dependent manner. This inhibitory effect was improved by IFNγ or IFNγ + TNFα, at UC-MSCs:PBMC ratio 1:10 and 1:30, whereas only IFNγ allowed to decrease significantly T cell proliferation at ratio 1:100. The manufacturing process of the UC-MSC-based ATMP was qualified and authorized by the French regulatory agency for clinical use (NCT04333368).

Conclusion

This work allowed to develop an investigational UC-MSC-based ATMP authorized for clinical use. Our results showed that an inflammatory environment preserves the biological properties of UC-MSCs with an improvement of their immunomodulatory functions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02637-7.

Current good manufacturing practice considerations for mesenchymal stromal cells as therapeutic agents

Producing human mesenchymal stromal cells (MSCs) for clinical use requires adherence to current good manufacturing practice (cGMP) standards. This is necessary for ensuring standardization and reproducibility through the manufacturing process, but also, for product quality and safety. However, the large-scale production of clinical-grade MSCs possesses unique regulatory challenges and hurdles related to the heterogeneous nature of MSC cultures as well as the complex manufacturing process. Following is a compilation of the major issues encountered in the manufacturing of MSCs for clinical use, and our views on the optimal characteristics of the final MSC product.

[CAR T cells as drugs for novel therapies (advanced therapy medicinal products)]

BACKGROUND

Two commercial chimeric antigen receptor (CAR) T cell products, axicabtagene-ciloleucel (Yescarta®) and tisagenlecleucel (Kymriah®), are registered for the treatment of B cell neoplasia, for which an increased supply of CAR T cell products is required.

PROBLEM

The production of patient-specific CAR T cells as advanced therapy medicinal products (ATMPs) poses considerable challenges with respect to logistics, regulation, and manufacturing.

METHOD

Review of the CAR T cell manufacturing process and the regulatory network, the current challenges, and future development capabilities of CAR T cells for adoptive immunotherapy.

RESULTS

CAR T cells are manufactured under individualized, laborious, good manufacturing practice-conforming processes in decentralized or in specialized centers. Starting from the patient's leukapheresis product, T cells are genetically engineered ex vivo with a CAR, amplified, and after extensive quality control re-applied to the patient. Most CAR T cell products are manufactured in a manual or semi-automated process; fully automated, supervised, and closed systems are increasingly applied to meet the need for a growing number of CAR T cell products. In this setting, research aims at providing allogeneic CAR T cell products or non-T cells such as natural killer cells for broad applications.

CONCLUSION

The significance of CAR T cells in adoptive immunotherapy is continuously growing. As individualized cell products, manufacturing requires highly efficient processes under the control of harmonized protocols and regulations so as to ensure the quality of the ATMP in view of increasing demand and to develop new fields in therapy.

Recent Advances in Good Manufacturing Practice-Grade Generation of Dendritic Cells

Dendritic cells (DCs) are pivotal regulators of immune responses, specialized in antigen presentation and bridging the gap between the innate and adaptive immune system. Due to these key features, DCs have become a pillar of the continuously growing field of cellular therapies. Here we review recent advances in good manufacturing practice strategies and their individual specificities in relation to DC production for clinical applications. These take into account both small-scale experimental approaches as well as automated systems for patient care.

Registration and local production of essential medicines in Uganda

Background

Universal access to high quality essential medicines is critical to sustainable development (SDG 3.8). However low- and middle-income countries struggle to ensure access to all medicines on their national essential medicines lists (EML). Market registration is the first step in determining both access and availability yet the extent to which essential medicines are registered for use at country level is not known. Companies apply for a marketing authorisation, however low price or lack of a market is a disincentive. Local production has been promoted to ensure availability of essential medicines but research in this area is also limited.

Methods

The study took place between 2011 and 2015. We systematically examined the registration status of medicines and vaccines listed in the Ugandan 2012 EML and conducted 20 interviews with regulators, ministry of health representatives, donors, and pharmaceutical producers and analysed quality assurance issues affecting registration, procurement, and local production of medicines in Uganda. In 2017 we conducted a further three interviews to clarify issues around non-registration of essential medicines highlighted by our analysis.

Results

Of the 566 essential medicines and vaccines nearly half (49%; 275/566) had no registered product in 2012. Of the 3130 registered products, just over a quarter (28%; 880/3130) were listed on the EML. Six local producers had registered 138 products of which 40 corresponded to 32 unique essential medicines. Interviews highlighted alternative routes to availability other than registration. Local producers faced considerable barriers to achieving international quality standards required for international procurement of medicines for the domestic market.

Conclusions

Monitoring and audit of the registration of essential and non-essential medicines should be a priority nationally and, regionally through harmonisation of registration requirements in the East African Community. National and regional manufacturing plans should consider local production of unregistered essential medicines.

Evaluation of a cell-based osteogenic formulation compliant with good manufacturing practice for use in tissue engineering

Proper bony tissue regeneration requires mechanical stabilization, an osteogenic biological activity and appropriate scaffolds. The latter two elements can be combined in a hydrogel format for effective delivery, so it can readily adapt to the architecture of the defect. We evaluated a Good Manufacturing Practice-compliant formulation composed of bone marrow-derived mesenchymal stromal cells in combination with bone particles (Ø = 0.25 to 1 µm) and fibrin, which can be readily translated into the clinical setting for the treatment of bone defects, as an alternative to bone tissue autografts. Remarkably, cells survived with unaltered phenotype (CD73⁺, CD90⁺, CD105⁺, CD31^-, CD45^-) and retained their osteogenic capacity up to 48 h after being combined with hydrogel and bone particles, thus demonstrating the stability of their identity and potency. Moreover, in a subchronic toxicity in vivo study, no toxicity was observed upon subcutaneous administration in athymic mice and signs of osteogenesis and vascularization were detected 2 months after administration. The preclinical data gathered in the present work, in compliance with current quality and regulatory requirements, demonstrated the feasibility of formulating an osteogenic cell-based tissue engineering product with a defined profile including identity, purity and potency (in vitro and in vivo), and the stability of these attributes, which complements the preclinical package required prior to move towards its use of prior to its clinical use.

Derivation of clinical-grade mesenchymal stromal cells from umbilical cord under chemically defined culture condition - platform for future clinical application

The use of animal serum in culture medium brings safety concerns and batch-to-batch variability, and thus may restrict the clinical use of ex vivo expanded mesenchymal stromal cells (MSCs). Clinically compliant MSCs should be developed in adherence to serum-free, xeno-free and chemically defined medium (S&XFM-CD). In this study, we develop a S&XFM-CD by replacing all serum components with synthetic alternatives for the derivation of clinical-grade umbilical cord-derived MSCs (UCMSCs). The critical aspects including characterization, safety concerns, potency and exogenous factors contamination risk of UCMSCs in S&XFM-CD are compared with serum-containing medium (SCM). UCMSCs in S&XFM-CD retain fibroblastic-like morphology and immunophenotype of MSCs, and exhibit superior clone efficiency, proliferation capacity, and osteogenic and chondrogenic differentiation potential compared with SCM. Moreover, UCMSCs in S&XFM-CD retain similar immunosuppressive potential, and exhibit superior secretion levels of bFGF, PDGF-BB and IGF-1 compared with SCM. In addition, UCMSCs in S&XFM-CD do not undergo transformation, preserve the normal karyotypes and genomic stability, and are less prone to senescence process after long-term in vitro culture, which conforms to the current guidance of international and national evaluation standard. The S&XFM-CD developed here may serve as a GMP-grade production platform of UCMSCs for future clinical application.

The challenge of developing human 3D organoids into medicines

The capacity of organoids to generate complex 3D structures resembling organs is revolutionizing the fields of developmental and stem cell biology. We are currently establishing the foundations for translational applications of organoids such as drug screening, personalized medicine and launching the future of cell therapy using organoids. However, clinical translation of organoids into cell replacement therapies is halted due to (A) a few preclinical studies demonstrating their efficacy and (B) the lack of robust, reproducible, and scalable methods of production in compliance with current pharmaceutical standards. In this issue of Stem Cell Research & Therapy [ref], Dossena and collaborators present a validated bioprocess design for large-scale production of human pancreatic organoids from cadaveric tissue in accordance with current good manufacturing practice. The authors also propose a set of specifications of starting materials and critical quality attributes of final products that are of interest to other developments provided that this type of medicines are different than any other medicinal product due to their complex composition and living nature of the active ingredient. Although large-scale production of functional cells secreting insulin is still a challenge, the development of methods such as the one presented by Dossena and collaborators contributes to move toward clinical use of organoids in the treatment of type 1 diabetes and opens avenues for future clinical use of organoids in degenerative pathologies.

Reproducibility of GMP-compliant production of therapeutic stressed peripheral blood mononuclear cell-derived secretomes, a novel class of biological medicinal products

BACKGROUND

The recent concept of secretome-based tissue regeneration has profoundly altered the field of regenerative medicine and offers promising novel therapeutic options. In contrast to medicinal products with a single active substance, cell-derived secretomes comprise pleiotropic bioactive ingredients, representing a major obstacle for reproducible drug product efficacy and warranting patient safety. Good manufacturing practice (GMP)-compliant production guarantees high batch-to-batch consistency and reproducible efficacy of biological medicinal products, but different batches of cellular secretomes produced under GMP have not been compared yet, and suitable quality control parameters have not been established. To this end, we analyzed diverse biological and functional parameters of different batches produced under GMP of the secretome obtained from γ-irradiated peripheral blood mononuclear cells with proven tissue regenerative properties in infarcted myocardium, stroke, spinal cord injury, and skin wounds.

METHODS

We quantified key secretome ingredients, including cytokines, lipids, and extracellular vesicles, and functionally assessed potency in tube formation assay, ex vivo aortic ring sprouting assay, and cell-based protein and reporter gene assays. Furthermore, we determined secretome stability in different batches after 6 months of storage at various ambient temperatures.

RESULTS

We observed that inter-batch differences in the bioactive components and secretome properties were small despite considerable differences in protein concentrations and potencies between individual donor secretomes. Stability tests showed that the analytical and functional properties of the secretomes remained stable when lyophilisates were stored at temperatures up to + 5 °C for 6 months.

CONCLUSIONS

We are the first to demonstrate the consistent production of cell-derived, yet cell-free secretome as a biological medicinal product. The results from this study provide the basis for selecting appropriate quality control parameters for GMP-compliant production of therapeutic cell secretomes and pave the way for future clinical trials employing secretomes in tissue regenerative medicine.

Cell Processing for 3D Bioprinting: Quality Requirements for Quality Assurance in Fundamental Research and Translation

Bioprinting is an additive manufacturing process where biomaterials-based inks are printed layer-by-layer to create three-dimensional (3D) structures that mimic natural tissues. Quality assurance for 3D bioprinting is paramount to undertaking fundamental research and preclinical and clinical product development. It forms part of quality management and is vital to reproducible and safe tissue fabrication, function, and regulatory approval for translational application. This chapter seeks to place the implementation of quality practices in 3D bioprinting front-of-mind, with emphasis on cell processing, although important to all components and procedures of the printing pipeline.

Use of Multipotent Mesenchymal Stromal Cells, Fibrin, and Scaffolds in the Production of Clinical Grade Bone Tissue Engineering Products

Tissue engineering products (TEP) are a new type of medicines resulting from the combination of cells, scaffolds, and/or signalling factors, which can be used for the regeneration of damaged tissues thus opening new avenues for the treatment of complex conditions. However, such combination of biologically active elements, particularly living cells, poses an unprecedented challenge for their production under pharmaceutical standards.In the methods presented here, we formulated two types of TEP based on the use of multipotent mesenchymal stromal cells with osteogenic potential combined with osteoinductive and osteoconductive bony particles from tissue bank embedded in a fibrin hydrogel that, altogether, can induce the generation of new tissue while adapting to the diverse architecture of bony defects. In agreement with pharmaceutical quality and regulatory requirements, procedures presented herein can be performed in compliance with current good manufacturing practices and be readily implemented in straightforward facilities at hospitals and academic institutions.

Exosomes in clinical trial and their production in compliance with good manufacturing practice

Exosomes, 60–200-nm extracellular vesicles secreted from cells, have been used as an active pharmaceutical ingredient or drug carrier in disease treatment. Human- and plant-derived exosomes are registered in clinical trials, but more complete reports are available for human-derived exosomes. Because exosomes act as vesicles and carry cell secreting components, they have been used as drug or peptide vehicles to treat diseases. The dendritic cells (DCs) and mesenchymal stem cells (MSCs) are two popular cell sources for exosome preparation. Exosomes from DCs can initiate inflammation in patients, particularly in patients with cancer, as they contain the tumor antigen to induce specific inflammation response. A well-established cell bank of MSCs is available, and these cells can be used as an alternative source for exosome preparation. The major application of MSC-derived exosomes is in inflammation treatment. Exosomes in clinical trials need to comply with good manufacturing practice (GMP). Three important issues are prevalent in GMP for exosomes, i.e., upstream of cell cultivation process, downstream of the purification process, and exosome quality control. This paper concisely reviews exosome development, including exosome generation and clinical trial application.

CART manufacturing process and reasons for academy-pharma collaboration

The success of genetically engineered T-cells modified with a chimeric antigen receptor as an adoptive cell immunotherapy and the subsequent last regulatory approvals of products based on this therapy are leading to a crescent number of both academic and pharmaceutical industry clinical trials testing new approaches of this "living drugs". The aim of this review is to outline the latest developments and regulatory considerations in this field, with a particular emphasis to differences and similarities between academic and industry approaches and the role they should play to coexist and move forward together. To do that, the main considerations for the manufacturing process are firstly discussed, from the chimeric antigen receptor design to final production steps, passing through ex vivo T-cell handling, gene delivery methods, patient´s final product infusion observations or possible associated side effects of this treatment.

A short-term plastic adherence incubation of the stromal vascular fraction leads to a predictable GMP-compliant cell-product

Introduction:Mesenchymal stromal/stem cells (MSCs) derived from fat tissue are an encouraging tool for regenerative medicine. They share properties similar to the bone marrow-derived MSCs, but the amount of MSCs per gram of fat tissue is 500x higher. The fat tissue can easily be digested by collagenase, releasing a heterogeneous cell fraction called stromal vascular fraction (SVF) which contains a variable amount of stromal/stem cells. In Europe, cell products like the SVF derived from fat tissue are considered advanced therapy medicinal product (ATMPs). As a consequence, the manufacturing process has to be approved via GMP-compliant process validation. The problem of the process validation for SVF is the heterogeneity of this fraction.

Methods: Here, we modified existing purification strategies by adding an additional plastic adherence incubation of maximal 20 hours after SVF isolation. The resulting cell fraction was characterized and compared to SVF as well as cultivated adipose-derived stromal/stem cells (ASCs) with respect to viability and cell yield, the expression of surface markers, differentiation potential and cytokine expression.

Results: Short-term incubation significantly reduced the heterogeneity of the resulting cell fraction compared to SVF. The cells were able to differentiate into adipocytes, chondrocytes, and osteoblasts. More importantly, they expressed trophic proteins which have been previously associated with the beneficial effects of MSCs. Furthermore, GMP compliance of the production process described herein was acknowledged by the national regulatory agencies (DE_BB_01_GMP_2017_1018).

Conclusion: Addition of a short purification-step after the SVF isolation is a cheap and fast strategy to isolate a homogeneous uncultivated GMP-compliant cell fraction of ASCs.

Improved GMP compliant approach to manipulate lipoaspirates, to cryopreserve stromal vascular fraction, and to expand adipose stem cells in xeno-free media

Background

The stromal vascular fraction (SVF) derived from adipose tissue contains adipose-derived stromal/stem cells (ASC) and can be used for regenerative applications. Thus, a validated protocol for SVF isolation, freezing, and thawing is required to manage product administration. To comply with Good Manufacturing Practice (GMP), fetal bovine serum (FBS), used to expand ASC in vitro, could be replaced by growth factors from platelet concentrates.

Methods

Throughout each protocol, GMP-compliant reagents and devices were used. SVF cells were isolated from lipoaspirates by a standardized enzymatic protocol. Cells were cryopreserved in solutions containing different albumin or serum and dimethylsulfoxide (DMSO) concentrations. Before and after cryopreservation, we analyzed: cell viability (by Trypan blue); immunophenotype (by flow cytometry); colony-forming unit-fibroblast (CFU-F) formation; and differentiation potential. ASC, seeded at different densities, were expanded in presence of 10% FBS or 5% supernatant rich in growth factors (SRGF) from platelets. The differentiation potential and cell transformation grade were tested in expanded ASC.

Results

We demonstrated that SVF can be obtained with a consistent yield (about 185 × 10³ cells/ml lipoaspirate) and viability (about 82%). Lipoaspirate manipulation after overnight storage at +4 °C reduced cell viability (−11.6%). The relative abundance of ASC (CD34⁺CD45⁻CD31^–) and endothelial precursors (CD34⁺CD45⁻CD31⁺) in the SVF product was about 59% and 42%, respectively. A period of 2 months cryostorage in autologous serum with added DMSO minimally affected post-thaw SVF cell viability as well as clonogenic and differentiation potentials. Viability was negatively affected when SVF was frozen at a cell concentration below 1.3 × 10⁶ cells/ml. Cell viability was not significantly affected after a freezing period of 1 year.

Independent of seeding density, ASC cultured in 5% SRGF exhibited higher growth rates when compared with 10% FBS. ASC expanded in both media showed unaltered identity (by flow cytometry) and were exempt from genetic lesions. Both 5% SRGF- and 10% FBS-expanded ASC efficiently differentiated to adipocytes, osteocytes, and chondrocytes.

Conclusions

This paper reports a GMP-compliant approach for freezing SVF cells isolated from adipose tissue by a standardized protocol. Moreover, an ASC expansion method in controlled culture conditions and without involvement of animal-derived additives was reported.

Human platelet lysate in mesenchymal stromal cell expansion according to a GMP grade protocol: a cell factory experience

BACKGROUND

The use of platelet lysate (PL) for the ex-vivo expansion of mesenchymal stromal/stem cells (MSCs) was initially proposed by Doucet et al. in 2005, as an alternative to animal serum. Moreover, regulatory authorities discourage the use of fetal bovine serum (FBS) or other animal derivatives, to avoid risk of zoonoses and xenogeneic immune reactions. Even if many studies investigated PL composition, there still are some open issues related to its use in ex-vivo MSC expansion, especially according to good manufacturing practice (GMP) grade protocols.

METHODS

As an authorized cell factory, we report our experience using standardized PL produced by Azienda Ospedaliero Universitaria Meyer Transfusion Service for MSC expansion according to a GMP grade clinical protocol. As suggested by other authors, we performed an in-vitro test on MSCs versus MSCs cultured with FBS that still represents the best way to test PL batches. We compared 12 MSC batches cultured with DMEM 5% PL with similar batches cultured with DMEM 10% FBS, focusing on the MSC proliferation rate, MSC surface marker expression, MSC immunomodulatory and differentiation potential, and finally MSC relative telomere length.

RESULTS

Results confirmed the literature data as PL increases cell proliferation without affecting the MSC immunophenotype, immunomodulatory potential, differentiation potential and relative telomere length.

CONCLUSIONS

PL can be considered a safe alternative to FBS for ex-vivo expansion of MSC according to a GMP grade protocol. Our experience confirms the literature data: a large number of MSCs for clinical applications can be obtained by expansion with PL, without affecting the MSC main features. Our experience underlines the benefits of a close collaboration between the PL producers (transfusion service) and the end users (cell factory) in a synergy of skills and experiences that can lead to standardized PL production.

Human serum and platelet lysate are appropriate xeno-free alternatives for clinical-grade production of human MuStem cell batches

BACKGROUND

Canine MuStem cells have demonstrated regenerative efficacy in a dog model of muscular dystrophy, and the recent characterization of human counterparts (hMuStem) has highlighted the therapeutic potential of this muscle-derived stem cell population. To date, these cells have only been generated in research-grade conditions. However, evaluation of the clinical efficacy of any such therapy will require the production of hMuStem cells in compliance with good manufacturing practices (GMPs). Because the current use of fetal bovine serum (FBS) to isolate and expand hMuStem cells raises several ethical, safety, and supply concerns, we assessed the use of two alternative xeno-free blood derivatives: human serum (HS) and a human platelet lysate (hPL).

METHODS

hMuStem cells were isolated and expanded in vitro in either HS-supplemented or hPL-supplemented media and the proliferation rate, clonogenicity, myogenic commitment potential, and oligopotency compared with that observed in FBS-supplemented medium. Flow cytometry and high-throughput 3'-digital gene expression RNA sequencing were used to characterize the phenotype and global gene expression pattern of hMuStem cells cultured with HS or hPL.

RESULTS

HS-supplemented and hPL-supplemented media both supported the isolation and long-term proliferation of hMuStem cells. Compared with FBS-based medium, both supplements enhanced clonogenicity and allowed for a reduction in growth factor supplementation. Neither supplement altered the cell lineage pattern of hMuStem cells. In vitro differentiation assays revealed a decrease in myogenic commitment and in the fusion ability of hMuStem cells when cultured with hPL. In return, this reduction of myogenic potential in hPL-supplemented cultures was rapidly reversed by substitution of hPL with HS or fibrinogen-depleted hPL. Moreover, culture of hMuStem cells in hPL hydrogel and fibrinogen-depleted hPL demonstrated that myogenic differentiation potential is maintained in heparin-free hPL derivatives.

CONCLUSIONS

Our findings indicate that HS and hPL are efficient and viable alternatives to FBS for the preparation of hMuStem cell batches in compliance with GMPs.

Reduction of Environmental Listeria Using Gaseous Ozone in a Cheese Processing Facility

A cheese processing facility seeking to reduce environmental Listeria colonization initiated a regime of ozonation across all production areas as an adjunct to its sanitation regimes. A total of 360 environmental samples from the facility were tested for Listeria over a 12-month period. A total of 15 areas before and 15 areas after ozonation were tested. Listeria isolations were significantly ( P < 0.001) reduced from 15.0% in the preozonation samples to 1.67% in the postozonation samples in all areas. No deleterious effects of ozonation were noted on the wall paneling, seals, synthetic floors, or cheese processing equipment. The ozonation regime was readily incorporated by sanitation staff into the existing good manufacturing practice program. The application of ozone may result in a significant reduction in the prevalence of Listeria in food processing facilities.

Manufacturing human mesenchymal stem cells at clinical scale: process and regulatory challenges

Human mesenchymal stem cell (hMSC)-based therapies are of increasing interest in the field of regenerative medicine. As economic considerations have shown, allogeneic therapy seems to be the most cost-effective method. Standardized procedures based on instrumented single-use bioreactors have been shown to provide billion of cells with consistent product quality and to be superior to traditional expansions in planar cultivation systems. Furthermore, under consideration of the complex nature and requirements of allogeneic hMSC-therapeutics, a new equipment for downstream processing (DSP) was successfully evaluated. This mini-review summarizes both the current state of the hMSC production process and the challenges which have to be taken into account when efficiently producing hMSCs for the clinical scale. Special emphasis is placed on the upstream processing (USP) and DSP operations which cover expansion, harvesting, detachment, separation, washing and concentration steps, and the regulatory demands.

Regulatory Considerations for NK Cells Used in Human Immunotherapy Applications

Translating cellular therapy from the laboratory to the clinic is a complicated process that involves scale-up of procedures to generate clinically relevant cell numbers, adaptation to reagents and equipment that are qualified for human use, establishing parameters of safety for reagents and equipment that are not already qualified for human use, codifying these processes into standards of practice and rules of conduct, and obtaining approval from regulatory bodies based on those codified standards and rules. As the laws and regulations that apply to cellular therapy will vary by time and geography, this chapter reviews some common key principles for the manufacturing of NK cells for human use that will need to be considered within the constraints of local policies and regulations.

Mesenchymal stem cells for cardiac repair: are the actors ready for the clinical scenario?

For years, sufficient progress has been made in treating heart failure following myocardial infarction; however, the social and economic burdens and the costs to world health systems remain high. Moreover, treatment advances have not resolved the underlying problem of functional heart tissue loss. In this field of research, for years we have actively explored innovative biotherapies for cardiac repair. Here, we present a general, critical overview of our experience in using mesenchymal stem cells, derived from cardiac adipose tissue and umbilical cord blood, in a variety of cell therapy and tissue engineering approaches. We also include the latest advances and future challenges, including good manufacturing practice and regulatory issues. Finally, we evaluate whether recent approaches hold potential for reliable translation to clinical trials.

Cost benefit of investment on quality in pharmaceutical manufacturing: WHO GMP pre- and post-certification of a Nigerian pharmaceutical manufacturer

Background

Pharmaceutical companies in Africa need to invest in both facilities and quality management systems to achieve good manufacturing practice (GMP) compliance. Compliance to international GMP standards is important to the attainment of World Health Organization (WHO) prequalification. However, most of the local pharmaceutical manufacturing companies may be deterred from investing in quality because of many reasons, ranging from financial constraints to technical capacity. This paper primarily evaluates benefits against the cost of investing in GMP, using a Nigerian pharmaceutical company, Chi Pharmaceuticals Limited, as a case study. This paper also discusses how to drive more local manufacturers to invest in quality to attain GMP compliance; and proffers practical recommendations for local manufacturers who would want to invest in quality to meet ethical and regulatory obligations.

Method

The cost benefit of improving the quality of Chi Pharmaceuticals Limited’s facilities and system to attain WHO GMP certification for the production of zinc sulfate 20-mg dispersible tablets was calculated by dividing the annual benefits derived from quality improvement interventions by the annual costs of implementing quality improvement interventions, referred to as a benefit-cost ratio (BCR).

Result

Cost benefit of obtaining WHO GMP certification for the production of zinc sulfate 20-mg dispersible tablets was 5.3 (95% confidence interval of 5.0–5.5).

Conclusion

Investment in quality improvement intervention is cost-beneficial for local manufacturing companies. Governments and regulators in African countries should support pharmaceutical companies striving to invest in quality. Collaboration of local manufacturing companies with global companies will further improve quality. Local pharmaceutical companies should be encouraged to key into development opportunities available for pharmaceutical companies in Africa.

Standardization of platelet releasate products for clinical applications in cell therapy: a mathematical approach

BACKGROUND

Standardized animal-free components are required for manufacturing cell-based medicinal products. Human platelet concentrates are sources of growth factors for cell expansion but such products are characterized by undesired variability. Pooling together single-donor products improves consistency, but the minimal pool sample size was never determined.

METHODS

Supernatant rich in growth factors (SRGF) derived from n = 44 single-donor platelet-apheresis was obtained by CaCl₂ addition. n = 10 growth factor concentrations were measured. The data matrix was analyzed by a novel statistical algorithm programmed to create 500 groups of random data from single-donor SRGF and to repeat this task increasing group statistical sample size from n = 2 to n = 20. Thereafter, in created groups (n = 9500), the software calculated means for each growth factor and, matching groups with the same sample size, the software retrieved the percent coefficient of variation (CV) between calculated means. A 20% CV was defined as threshold. For validation, we assessed the CV of concentrations measured in n = 10 pools manufactured according to algorithm results. Finally, we compared growth rate and differentiation potential of adipose-derived stromal/stem cells (ASC) expanded by separate SRGF pools.

RESULTS

Growth factor concentrations in single-donor SRGF were characterized by high variability (mean (pg/ml)-CV); VEGF: 950-81.4; FGF-b: 27-74.6; PDGF-AA: 7883-28.8; PDGF-AB: 107834-32.5; PDGF-BB: 11142-48.4; Endostatin: 305034-16.2; Angiostatin: 197284-32.9; TGF-β1: 68382-53.7; IGF-I: 70876-38.3; EGF: 2411-30.2). In silico performed analysis suggested that pooling n = 16 single-donor SRGF reduced CV below 20%. Concentrations measured in 10 pools of n = 16 single SRGF were not different from mean values measured in single SRGF, but the CV was reduced to or below the threshold. Separate SRGF pools failed to differently affect ASC growth rate (slope pool A = 0.6; R² = 0.99; slope pool B = 0.7; R² 0.99) or differentiation potential.

DISCUSSION

Results deriving from our algorithm and from validation utilizing real SRGF pools demonstrated that pooling n = 16 single-donor SRGF products can ameliorate variability of final growth factor concentrations. Different pools of n = 16 single donor SRGF displayed consitent capability to modulate growth and differentiation potential of expanded ASC. Increasing the pool size should not further improve product composition.

EBV-Directed T Cell Therapeutics for EBV-Associated Lymphomas

Epstein Barr virus (EBV) is a human gamma herpes virus that establishes latency in B cells after primary infection. EBV generally only causes a mild, self-limiting viral illness but is also associated with several malignancies including posttransplantation lymphoproliferative disorder in the immunosuppressed host as well as Hodgkin and non-Hodgkin lymphoma in the immune competent host. The expression of EBV antigens by lymphoma has important applications as targets for adoptive T cell therapy. However, as many lymphomas only express subdominant EBV antigens that are less immunogenic, novel strategies are needed to manufacture EBV-specific T cell products specific for Latent Membrane Protein 1 (LMP1) and LMP2, which are expressed in lymphomas with type II and III latency. While several techniques for manufacturing EBV-CTLs are described in the literature, this chapter focuses on one method for generating Good Manufacturing Practice (GMP)-compliant EBV-specific T cell products that are enriched with LMP1 and LMP2.

Good manufacturing practice requirements for the production of tissue vitrification and warming and recovery kits for clinical research

Products that are manufactured for use in a clinical trial, with the intent of gaining US Food and Drug Administration (FDA) approval for clinical use, must be produced under an FDA approved investigational new drug (IND) application. We describe work done toward generating reliable methodology and materials for preserving ovarian cortical tissue through a vitrification kit and reviving this tissue through a warming and recovery kit. We have described the critical steps, procedures, and environments for manufacturing products with the intent of submitting an IND. The main objective was to establish an easy-to-use kit that would ensure standardized procedures for quality tissue preservation and recovery across the 117 Oncofertility Consortium sites around the globe. These kits were developed by breaking down the components and steps of a research protocol and recombining them in a way that considers component stability and use in a clinical setting. The kits were manufactured utilizing current good manufacturing practice (cGMP) requirements and environment, along with current good laboratory practices (cGLP) techniques. Components of the kit were tested for sterility and endotoxicity, and morphological endpoint release criteria were established. We worked with the intended down-stream users of these kits for development of the kit instructions. Our intention is to test these initial kits, developed and manufactured here, for submission of an IND and to begin clinical testing for preserving the ovarian tissue that may be used for future restoration of fertility and/or hormone function in women who have gonadal dysgenesis from gonadotoxic treatment regimens or disease.

An important role for adenine, cholera toxin, hydrocortisone and triiodothyronine in the proliferation, self-renewal and differentiation of limbal stem cells in vitro

The cornea is a self-renewing tissue located at the front of the eye. Its transparency is essential for allowing light to focus onto the retina for visual perception. The continuous renewal of corneal epithelium is supported by limbal stem cells (LSCs) which are located in the border region between conjunctiva and cornea known as the limbus. Ex vivo expansion of LSCs has been successfully applied in the last two decades to treat patients with limbal stem cell deficiency (LSCD). Various methods have been used for their expansion, yet the most widely used culture media contains a number of ingredients derived from animal sources which may compromise the safety profile of human LSC transplantation. In this study we sought to understand the role of these components namely adenine, cholera toxin, hydrocortisone and triiodothyronine with the aim of re-defining a safe and GMP compatible minimal media for the ex vivo expansion of LSCs on human amniotic membrane. Our data suggest that all four components play a critical role in maintaining LSC proliferation and promoting LSC self-renewal. However removal of adenine and triiodothyronine had a more profound impact and led to LSC differentiation and loss of viability respectively, suggesting their essential role for ex vivo expansion of LSCs. Replacement of each of the components with GMP-grade reagents resulted in equal growth to non-GMP grade media, however an enhanced differentiation of LSCs was observed, suggesting that additional combinations of GMP grade reagents need to be tested to achieve similar or better level of LSC maintenance in the same manner as the traditional LSC media.

•

Adenine, cholera toxin, hydrocortisone and triiodothyronine are essential for LSCs proliferation and self-renewal.

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Adenine and triiodothyronine had a more profound impact as their removal led to LSC differentiation and loss of viability.

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Removal of each of four components from traditional culture media may pose a risk for clinical translations.

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New media composition in compliance with Good Manufacturing Practice is proposed.

Potential use of lymph node-derived HPV-specific T cells for adoptive cell therapy of cervical cancer

Adoptive transfer of tumor-specific T cells, expanded from tumor-infiltrating lymphocytes or from peripheral blood, is a promising immunotherapeutic approach for the treatment of cancer. Here, we studied whether the tumor-draining lymph nodes (TDLN) of patients with human papillomavirus (HPV)-induced cervical cancer can be used as a source for ACT. The objectives were to isolate lymph node mononuclear cells (LNMC) from TDLN and optimally expand HPV-specific CD4+ and CD8+ T cells under clinical grade conditions. TDLN were isolated from 11 patients with early-stage cervical cancer during radical surgery. Isolated lymphocytes were expanded in the presence of HPV16 E6 and E7 clinical grade synthetic long peptides and IL-2 for 22 days and then analyzed for HPV16 specificity by proliferation assay, multiparameter flow cytometry and cytokine analysis as well as for CD25 and FoxP3 expression. Stimulation of LNMC resulted in expansion of polyclonal HPV-specific T cells in all patients. On average a 36-fold expansion of a CD4+ and/or CD8+ HPV16-specific T cell population was observed, which maintained its capacity for secondary expansion. The T helper type 1 cytokine IFNγ was produced in all cell cultures and in some cases also the Th2 cytokines IL-10 and IL-5. The procedure was highly reproducible, as evidenced by complete repeats of the stimulation procedures under research and under full good manufacturing practice conditions. In conclusion, TDLN represent a rich source of polyclonal HPV16 E6- and E7-specific T cells, which can be expanded under clinical grade conditions for adoptive immunotherapy in patients with cervical cancer.

How to achieve safe, high-quality clinical studies with non-Medicinal Investigational Products? A practical guideline by using intra-bronchial carbon nanoparticles as case study

BACKGROUND

Clinical studies investigating medicinal products need to comply with laws concerning good clinical practice (GCP) and good manufacturing practice (GMP) to guarantee the quality and safety of the product, to protect the health of the participating individual and to assure proper performance of the study. However, there are no specific regulations or guidelines for non-Medicinal Investigational Products (non-MIPs) such as allergens, enriched food supplements, and air pollution components. As a consequence, investigators will avoid clinical research and prefer preclinical models or in vitro testing for e.g. toxicology studies.

THE AIM OF THIS ARTICLE IS TO

1) briefly review the current guidelines and regulations for Investigational Medicinal Products; 2) present a standardised approach to ensure the quality and safety of non-MIPs in human in vivo research; and 3) discuss some lessons we have learned.

METHODS AND RESULTS

We propose a practical line of approach to compose a clarifying product dossier (PD), comprising the description of the production process, the analysis of the raw and final product, toxicological studies, and a thorough risk-benefit-analysis. This is illustrated by an example from a human in vivo research model to study exposure to air pollutants, by challenging volunteers with a suspension of carbon nanoparticles (the component of ink cartridges for laser printers).

CONCLUSION

With this novel risk-based approach, the members of competent authorities are provided with standardised information on the quality of the product in relation to the safety of the participants, and the scientific goal of the study.

Automation of cellular therapy product manufacturing: results of a split validation comparing CD34 selection of peripheral blood stem cell apheresis product with a semi-manual vs. an automatic procedure

Background

Automation of cell therapy manufacturing promises higher productivity of cell factories, more economical use of highly-trained (and costly) manufacturing staff, facilitation of processes requiring manufacturing steps at inconvenient hours, improved consistency of processing steps and other benefits. One of the most broadly disseminated engineered cell therapy products is immunomagnetically selected CD34+ hematopoietic “stem” cells (HSCs).

Methods

As the clinical GMP-compliant automat CliniMACS Prodigy is being programmed to perform ever more complex sequential manufacturing steps, we developed a CD34+ selection module for comparison with the standard semi-automatic CD34 “normal scale” selection process on CliniMACS Plus, applicable for 600 × 10⁶ target cells out of 60 × 10⁹ total cells. Three split-validation processings with healthy donor G-CSF-mobilized apheresis products were performed; feasibility, time consumption and product quality were assessed.

Results

All processes proceeded uneventfully. Prodigy runs took about 1 h longer than CliniMACS Plus runs, albeit with markedly less hands-on operator time and therefore also suitable for less experienced operators. Recovery of target cells was the same for both technologies. Although impurities, specifically T- and B-cells, were 5 ± 1.6-fold and 4 ± 0.4-fold higher in the Prodigy products (p = ns and p = 0.013 for T and B cell depletion, respectively), T cell contents per kg of a virtual recipient receiving 4 × 10⁶ CD34+ cells/kg was below 10 × 10³/kg even in the worst Prodigy product and thus more than fivefold below the specification of CD34+ selected mismatched-donor stem cell products. The products’ theoretical clinical usability is thus confirmed.

Conclusions

This split validation exercise of a relatively short and simple process exemplifies the potential of automatic cell manufacturing. Automation will further gain in attractiveness when applied to more complex processes, requiring frequent interventions or handling at unfavourable working hours, such as re-targeting of T-cells.

Concentrations of antibiotics predicted to select for resistant bacteria: Proposed limits for environmental regulation

There are concerns that selection pressure from antibiotics in the environment may accelerate the evolution and dissemination of antibiotic-resistant pathogens. Nevertheless, there is currently no regulatory system that takes such risks into account. In part, this is due to limited knowledge of environmental concentrations that might exert selection for resistant bacteria. To experimentally determine minimal selective concentrations in complex microbial ecosystems for all antibiotics would involve considerable effort. In this work, our aim was to estimate upper boundaries for selective concentrations for all common antibiotics, based on the assumption that selective concentrations a priori need to be lower than those completely inhibiting growth. Data on Minimal Inhibitory Concentrations (MICs) were obtained for 111 antibiotics from the public EUCAST database. The 1% lowest observed MICs were identified, and to compensate for limited species coverage, predicted lowest MICs adjusted for the number of tested species were extrapolated through modeling. Predicted No Effect Concentrations (PNECs) for resistance selection were then assessed using an assessment factor of 10 to account for differences between MICs and minimal selective concentrations. The resulting PNECs ranged from 8 ng/L to 64 μg/L. Furthermore, the link between taxonomic similarity between species and lowest MIC was weak. This work provides estimated upper boundaries for selective concentrations (lowest MICs) and PNECs for resistance selection for all common antibiotics. In most cases, PNECs for selection of resistance were below available PNECs for ecotoxicological effects. The generated PNECs can guide implementation of compound-specific emission limits that take into account risks for resistance promotion.

Isolation and proliferation of umbilical cord tissue derived mesenchymal stem cells for clinical applications

Umbilical cord (UC) is a rich source of rapidly proliferating mesenchymal stem cells (MSCs) that are easily cultured on a large-scale. Clinical applications of UC-MSCs include graft-versus-host disease, and diabetes mellitus types 1 and 2. UC-MSCs should be isolated and proliferated according to good manufacturing practice (GMP) with animal component-free medium, quality assurance, and quality control for their use in clinical applications. This study developed a GMP standard protocol for UC-MSC isolation and culture. UC blood and UC were collected from the same donors. Blood vasculature was removed from UC. UC blood was used as a source of activated platelet rich plasma (aPRP). Small fragments (1-2 mm(2)) of UC membrane and Wharton's jelly were cut and cultured in DMEM/F12 medium containing 1 % antibiotic-antimycotic, aPRP (2.5, 5, 7.5 and 10 %) at 37 °C in 5 % CO2. The MSC properties of UC-MSCs at passage 5 such as osteoblast, chondroblast and adipocyte differentiation, and markers including CD13, CD14, CD29, CD34, CD44, CD45, CD73, CD90, CD105, and HLA-DR were confirmed. UC-MSCs also were analyzed for karyotype, expression of tumorigenesis related genes, cell cycle, doubling time as well as in vivo tumor formation in NOD/SCID mice. Control cells consisted of UC-MSCs cultured in DMEM/F12 plus 1 % antibiotic-antimycotic, and 10 % fetal bovine serum (FBS). All UC-MSC (n = 30) samples were successfully cultured in medium containing 7.5 and 10 % aPRP, 92 % of samples grew in 5.0 % aPRP, 86 % of samples in 2.5 % aPRP, and 72 % grew in 10 % FBS. UC-MSCs in these four groups exhibited similar marker profiles. Moreover, the proliferation rates in medium with PRP, especially 7.5 and 10 %, were significantly quicker compared with 2.5 and 5 % aPRP or 10 % FBS. These cells maintained a normal karyotype for 15 sub-cultures, and differentiated into osteoblasts, chondroblasts, and adipocytes. The analysis of pluripotent cell markers showed UC-MSCs maintained the expression of the oncogenes Nanog and Oct4 after long term culture but failed to transfer tumors in NOD/SCID mice. Replacing FBS with aPRP in the culture medium for UC tissues allowed the successful isolation of UC-MSCs that satisfy the minimum standards for clinical applications.

Setting Up a Haplobank: Issues and Solutions

The development of induced pluripotent stem cells offers the possibility of the scalable manufacture of cellular therapies for regenerative medicine. Moreover, donors can be selected on the basis of major transplant antigen systems to match the widest possible number of recipients worldwide, reducing the likely risk of immunological rejection and the degree of immune suppression or tolerance required. If such cell lines are to be broadly available, there will need to be mutual recognition of common standards across different jurisdictions. Extensive international collaboration will be required around issues such as determination of the optimal homozygous human leukocyte antigens (HLA) panel, donor selection, screening and consent, good manufacturing practice (GMP), standards and quality control and regulatory legislation. The challenges in establishing a global GMP induced pluripotent stem cell (iPSC) haplobank are formidable. We argue that now is the time to attempt to reach international agreement around common standards for GMP iPSC manufacture before the field develops in a fragmented manner.

Clinical Grade Human Adipose Tissue-Derived Mesenchymal Stem Cell Banking

In this study, our aim was to produce a generation of GMP-grade adipose tissue-derived mesenchymal stem cells for clinical applications. According to our results, we fulfill to establish consistent and also reproducible current good manufacturing practice (cGMP) compliant adipose tissue-derived mesenchymal stem cells from five female donors. The isolated cells were cultured in DMEM supplemented with 10% fetal bovine serum and characterized by standard methods. Moreover, karyotyping was performed to evaluate chromosomal stability. Mean of donors' age was 47.6 ± 8.29 year, mean of cell viability was 95.6 ± 1.51%, and cell count was between 9×106 and 14×106 per microliter with the mean of 12.2×106 ± 2863564.21 per microliter. The main aim of this project was demonstrating the feasibility of cGMP-compliant and clinical grade adipose tissue-derived mesenchymal stem cells preparation and banking for clinical cell transplantation trials.