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1.
Acta Neuropathol ; 139(6): 965-976, 2020 06.
Article in English | MEDLINE | ID: mdl-32232565

ABSTRACT

Widespread dietary exposure of the population of Britain to bovine spongiform encephalopathy (BSE) prions in the 1980s and 1990s led to the emergence of variant Creutzfeldt-Jakob Disease (vCJD) in humans. Two previous appendectomy sample surveys (Appendix-1 and -2) estimated the prevalence of abnormal prion protein (PrP) in the British population exposed to BSE to be 237 per million and 493 per million, respectively. The Appendix-3 survey was recommended to measure the prevalence of abnormal PrP in population groups thought to have been unexposed to BSE. Immunohistochemistry for abnormal PrP was performed on 29,516 samples from appendices removed between 1962 and 1979 from persons born between 1891 through 1965, and from those born after 1996 that had been operated on from 2000 through 2014. Seven appendices were positive for abnormal PrP, of which two were from the pre-BSE-exposure era and five from the post BSE-exposure period. None of the seven positive samples were from appendices removed before 1977, or in patients born after 2000 and none came from individuals diagnosed with vCJD. There was no statistical difference in the prevalence of abnormal PrP across birth and exposure cohorts. Two interpretations are possible. Either there is a low background prevalence of abnormal PrP in human lymphoid tissues that may not progress to vCJD. Alternatively, all positive specimens are attributable to BSE exposure, a finding that would necessitate human exposure having begun in the late 1970s and continuing through the late 1990s.


Subject(s)
Creutzfeldt-Jakob Syndrome/epidemiology , Encephalopathy, Bovine Spongiform/epidemiology , Prion Proteins/metabolism , Prions/metabolism , Animals , Appendix/metabolism , Brain/metabolism , Brain/virology , Cattle , Creutzfeldt-Jakob Syndrome/metabolism , Encephalopathy, Bovine Spongiform/metabolism , Humans , Prevalence
2.
Int J Adv Manuf Technol ; 106(3): 1085-1103, 2020.
Article in English | MEDLINE | ID: mdl-31983799

ABSTRACT

Establishing how to effectively manufacture cell therapies is an industry-level problem. Decentralised manufacturing is of increasing importance, and its challenges are recognised by healthcare regulators with deviations and comparability issues receiving specific attention from them. This paper is the first to report the deviations and other risks encountered when implementing the expansion of human pluripotent stem cells (hPSCs) in an automated three international site-decentralised manufacturing setting. An experimental demonstrator project expanded a human embryonal carcinoma cell line (2102Ep) at three development sites in France, Germany and the UK using the CompacT SelecT (Sartorius Stedim, Royston, UK) automated cell culture platform. Anticipated variations between sites spanned material input, features of the process itself and production system details including different quality management systems and personnel. Where possible, these were pre-addressed by implementing strategies including standardisation, cell bank mycoplasma testing and specific engineering and process improvements. However, despite such measures, unexpected deviations occurred between sites including software incompatibility and machine/process errors together with uncharacteristic contaminations. Many only became apparent during process proving or during the process run. Further, parameters including growth rate and viability discrepancies could only be determined post-run, preventing 'live' corrective measures. The work confirms the critical nature of approaches usually taken in Good Manufacturing Practice (GMP) manufacturing settings and especially emphasises the requirement for monitoring steps to be included within the production system. Real-time process monitoring coupled with carefully structured quality systems is essential for multiple site working including clarity of decision-making roles. Additionally, an over-reliance upon post-process visual microscopic comparisons has major limitations; it is difficult for non-experts to detect deleterious culture changes and such detection is slow.

3.
Regen Med ; 14(11): 1057-1069, 2019 11.
Article in English | MEDLINE | ID: mdl-31718456

ABSTRACT

Current cell therapy product limitations include the need for in-depth product understanding to ensure product potency, safety and purity. New technologies require development and validation to address issues of production scale-up to meet clinical need; assays are required for process control, validation and release. Prior to clinical realization, an understanding of production processes is required to implement process changes that are essential for process control. Identification of key parameters forms the basis of process tolerances, allowing for validated, adaptive manufacturing processes. This enables greater process control and yield while withstanding regulatory scrutiny. This report summaries key milestones in specifically for ventral midbrain dopaminergic neuroprogenitor differentiation and key translational considerations and recommendations to enable successful, robust and reproducible current cell therapy product-manufacturing.


Subject(s)
Cell Differentiation , Dopaminergic Neurons/cytology , Mesencephalon/cytology , Parkinson Disease/therapy , Carcinogenesis/pathology , Humans , Translational Research, Biomedical
4.
Regen Med ; 14(3): 243-255, 2019 03.
Article in English | MEDLINE | ID: mdl-30938271

ABSTRACT

Human stem cells have the potential to transform medicine. However, hurdles remain to ensure that manufacturing processes produce safe and effective products. A thorough understanding of the biological processes occurring during manufacture is fundamental to assuring these qualities and thus, their acceptability to regulators and clinicians. Leaders in both human pluripotent and somatic stem cells, were brought together with experts in clinical translation, biomanufacturing and regulation, to discuss key issues in assuring appropriate manufacturing conditions for delivery of effective and safe products from these cell types. This report summarizes the key issues discussed and records consensus reached by delegates and emphasizes the need for accurate language and nomenclature in the scientific discourse around stem cells.


Subject(s)
Adult Stem Cells/cytology , Cell Culture Techniques/methods , Cell Differentiation , Cell- and Tissue-Based Therapy/methods , Pluripotent Stem Cells/cytology , Regenerative Medicine , Congresses as Topic , Humans
5.
Sex Transm Infect ; 95(8): 608-613, 2019 12.
Article in English | MEDLINE | ID: mdl-31028226

ABSTRACT

BACKGROUND: Human papillomavirus (HPV) vaccination for gay, bisexual and other men who have sex with men (GBMSM) aged up to 45 years attending sexual health clinics (SHC) and HIV clinics began in England as a pilot in June 2016, with national roll-out from April 2018. The recommended course is three doses of the quadrivalent HPV vaccine over one to 2 years. We present the methodology and results of monitoring vaccination uptake (initiation and completion), and attendance patterns, during the pilot phase. METHODS: Total numbers of eligible GBMSM receiving HPV vaccine doses were extracted from routine datasets from pilot start to end of March 2018. Numbers of attendances since January 2009 were extracted and tested for trends before and after introduction of HPV vaccination. RESULTS: Overall, first dose uptake was 49.1 % (23 619/48 095), with clinics with highest data completeness achieving close to 90% uptake during the pilot period. Refusals were very low (3.5%). There was no evidence of increases in the number of GBMSM attendances at pilot SHC. CONCLUSIONS: HPV vaccination has not caused important deviations to expected attendance patterns of GBMSM at SHC throughout the pilot phase. Overall, recorded initiation has been encouraging given known issues with data recording, as is current status of second and third dose completion. Attendances, vaccination initiation and completion will continue to be monitored alongside surveillance of anogenital warts diagnoses and of rectal HPV prevalence.


Subject(s)
Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18/administration & dosage , Immunization/methods , Papillomavirus Infections/prevention & control , Sexual and Gender Minorities , Vaccination Coverage , Adolescent , Adult , England , Humans , Male , Middle Aged , Young Adult
6.
Euro Surveill ; 24(8)2019 Feb.
Article in English | MEDLINE | ID: mdl-30808443

ABSTRACT

BACKGROUND: Opportunistic human papillomavirus (HPV) vaccination for men who have sex with men (MSM) was piloted in sexual health clinics (SHC) in England between 2016 and 2018. AIM: to evaluate the pilot's first year (April 2016-March 2017) in terms of feasibility, acceptability, uptake, impact and equity and interpret the outcome in the context of wide HPV vaccination policy. METHODS: Attendance and uptake data from routine SHC surveillance datasets and a cross-sectional survey administered to individuals receiving the vaccine were analysed. RESULTS: Among 18,875 eligible MSM, 8,580 (45.5%) were recorded as having received one HPV vaccine dose, decreasing slightly with increasing age, and uptake was higher in rural than urban areas. Survey results suggested that of those receiving the first dose of HPV vaccine, 8% were new attendees and that among those, less than 11% attended just to receive the vaccine. Of those having their first HPV vaccination, 95% indicated they would like to receive the next vaccine doses at the same clinic and 85% of patients reported accessing other services when visiting SHC for the first dose of vaccine. CONCLUSION: An opportunistic HPV vaccination programme for MSM can be delivered in an acceptable and, as far as can be evaluated, equitable manner, without major disruption to SHC and HIV clinics.


Subject(s)
Ambulatory Care Facilities/statistics & numerical data , Health Knowledge, Attitudes, Practice , Homosexuality, Male/statistics & numerical data , Papillomavirus Infections/prevention & control , Papillomavirus Vaccines/administration & dosage , Patient Acceptance of Health Care/statistics & numerical data , Vaccination/statistics & numerical data , Adolescent , Adult , Age Distribution , Cross-Sectional Studies , Feasibility Studies , Humans , Immunization , Male , Papillomaviridae , Papillomavirus Infections/epidemiology , Papillomavirus Infections/virology , Program Evaluation , Rural Population , Urban Population
7.
J Tissue Eng Regen Med ; 12(1): e368-e378, 2018 01.
Article in English | MEDLINE | ID: mdl-27696710

ABSTRACT

Manufacture of red blood cells (RBCs) from progenitors has been proposed as a method to reduce reliance on donors. Such a process would need to be extremely efficient for economic viability given a relatively low value product and high (2 × 1012 ) cell dose. Therefore, the aim of these studies was to define the productivity of an industry standard stirred-tank bioreactor and determine engineering limitations of commercial red blood cells production. Cord blood derived CD34+ cells were cultured under erythroid differentiation conditions in a stirred micro-bioreactor (Ambr™). Enucleated cells of 80% purity could be created under optimal physical conditions: pH 7.5, 50% oxygen, without gas-sparging (which damaged cells) and with mechanical agitation (which directly increased enucleation). O2 consumption was low (~5 × 10-8  µg/cell.h) theoretically enabling erythroblast densities in excess of 5 × 108 /ml in commercial bioreactors and sub-10 l/unit production volumes. The bioreactor process achieved a 24% and 42% reduction in media volume and culture time, respectively, relative to unoptimized flask processing. However, media exchange limited productivity to 1 unit of erythroblasts per 500 l of media. Systematic replacement of media constituents, as well as screening for inhibitory levels of ammonia, lactate and key cytokines did not identify a reason for this limitation. We conclude that the properties of erythroblasts are such that the conventional constraints on cell manufacturing efficiency, such as mass transfer and metabolic demand, should not prevent high intensity production; furthermore, this could be achieved in industry standard equipment. However, identification and removal of an inhibitory mediator is required to enable these economies to be realized. Copyright © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd.


Subject(s)
Bioreactors , Blood Cells/cytology , Cell- and Tissue-Based Therapy , Blood Cells/drug effects , Cell Count , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cytokines/metabolism , Erythroblasts/cytology , Erythroblasts/drug effects , Humans , Metabolome , Oxygen/pharmacology
8.
Regen Med ; 11(5): 483-92, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27404768

ABSTRACT

This paper summarizes the proceedings of a workshop held at Trinity Hall, Cambridge to discuss comparability and includes additional information and references to related information added subsequently to the workshop. Comparability is the need to demonstrate equivalence of product after a process change; a recent publication states that this 'may be difficult for cell-based medicinal products'. Therefore a well-managed change process is required which needs access to good science and regulatory advice and developers are encouraged to seek help early. The workshop shared current thinking and best practice and allowed the definition of key research questions. The intent of this report is to summarize the key issues and the consensus reached on each of these by the expert delegates.


Subject(s)
Pluripotent Stem Cells/transplantation , Regenerative Medicine , Biotechnology/methods , Biotechnology/trends , Humans , Manufacturing and Industrial Facilities , Regenerative Medicine/legislation & jurisprudence , Regenerative Medicine/methods , Regenerative Medicine/trends , United Kingdom
9.
Regen Med ; 10(1): 49-64, 2015.
Article in English | MEDLINE | ID: mdl-25562352

ABSTRACT

Cell-based therapies have the potential to make a large contribution toward currently unmet patient need and thus effective manufacture of these products is essential. Many challenges must be overcome before this can become a reality and a better definition of the manufacturing requirements for cell-based products must be obtained. The aim of this study is to inform industry and academia of current cell-based therapy clinical development and to identify gaps in their manufacturing requirements. A total of 1342 active cell-based therapy clinical trials have been identified and characterized based on cell type, target indication and trial phase. Multiple technologies have been assessed for the manufacture of these cell types in order to facilitate product translation and future process development.


Subject(s)
Cell Culture Techniques/methods , Cell- and Tissue-Based Therapy/methods , Translational Research, Biomedical/methods , Clinical Trials as Topic , Humans , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/cytology
10.
Regen Med ; 9(6): 799-815, 2014.
Article in English | MEDLINE | ID: mdl-25431916

ABSTRACT

Academic centers, hospitals and small companies, as typical development settings for UK regenerative medicine assets, are significant contributors to the development of autologous cell-based therapies. Often lacking the appropriate funding, quality assurance heritage or specialist regulatory expertise, qualifying aseptic cell processing facilities for GMP compliance is a significant challenge. The qualification of a new Cell Therapy Manufacturing Facility with automated processing capability, the first of its kind in a UK academic setting, provides a unique demonstrator for the qualification of small-scale, automated facilities for GMP-compliant manufacture of autologous cell-based products in these settings. This paper shares our experiences in qualifying the Cell Therapy Manufacturing Facility, focusing on our approach to streamlining the qualification effort, the challenges, project delays and inefficiencies we encountered, and the subsequent lessons learned.


Subject(s)
Academic Medical Centers/legislation & jurisprudence , Academic Medical Centers/standards , Cell- and Tissue-Based Therapy/standards , Regenerative Medicine/legislation & jurisprudence , Regenerative Medicine/standards , Automation , Humans , Transplantation, Autologous
11.
Cell Stem Cell ; 11(6): 735-9, 2012 Dec 07.
Article in English | MEDLINE | ID: mdl-23217418

ABSTRACT

During Q2-Q3 2012, the cell therapy industry benefited from a number of positive external influences including advantageous changes to future FDA regulation, but stock market activity was highly mixed. The FDA approved two more products and an appreciable number of public-company-sponsored clinical trials are progressing through phases 1-3.


Subject(s)
Cell- and Tissue-Based Therapy/economics , Drug Industry/economics , Internationality , Clinical Trials as Topic/economics , Clinical Trials as Topic/legislation & jurisprudence , Commerce/economics , Drug Industry/legislation & jurisprudence , Humans , Legislation as Topic , Regenerative Medicine/economics , Regenerative Medicine/legislation & jurisprudence , Research Support as Topic/economics , United Kingdom , United States , United States Department of Defense
12.
Atherosclerosis ; 165(2): 241-9, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12417274

ABSTRACT

Monocyte adhesion to and transmigration across the endothelium are initiating steps in atherogenesis. Cytokine-induced adhesion molecule expression in human umbilical vein endothelial cells (HUVEC) has been reported to be inhibited by either native HDL or reconstituted discoidal HDL (rHDL). In the present study we investigated these putative anti-atherosclerotic effects of HDL and rHDL in a more physiologically relevant cell type, i.e. human aortic endothelial cells (HAEC). HDL isolated by ultracentrifugation from eleven healthy subjects or rHDL made with apoA-I and either 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine (PLPC), or 1,2-dimyristoyl-sn-glycero-3-phosphocholine was incubated for 16 h with HAEC prior to stimulation with tumor necrosis factor-alpha (TNFalpha, 100 U/ml). Expression of E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) was measured by cell ELISA and Northern blot analysis. HDL (0.25, 0.5, 1.0 and 2.0 mgprotein/ml) failed to significantly inhibit TNFalpha-induced mRNA and protein expression of all three adhesion molecules. Furthermore, of the three rHDL preparations (16 micromol/l apoA-I) only that containing the polyunsaturated PLPC significantly reduced TNFalpha-induced VCAM-1 expression (by 29.9+/-9.1%). These data contrast with previously reported results using plasma HDL and HUVEC, and show that human HDL and rHDL, except for PLPC-rHDL, are ineffective inhibitors of TNFalpha-induced adhesion molecule expression in HAEC. The ability of polyunsaturated phospholipids in HDL to affect endothelial activation remains to be further investigated.


Subject(s)
Endothelium, Vascular/metabolism , Lipoproteins, HDL/pharmacology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Vascular Cell Adhesion Molecule-1/metabolism , Blotting, Northern , E-Selectin/metabolism , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Humans , Tumor Necrosis Factor-alpha/physiology , Umbilical Veins
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