Using cell surface antigens for the isolation of human photoreceptor precursor cells for retinal stem cell therapy

Lead Research Organisation: University College London
Department Name: Institute of Child Health

Abstract

Diseases of the retina resulting in the death of the light-sensing photoreceptor cells are the leading cause of blindness in the developed world. These conditions affect 1 in 3000 people from birth and more than 10% of the ageing population. They are currently untreatable and irreversible. We recently demonstrated in proof-of-concept experiments in mice that replacing lost photoreceptors by cell transplantation is a feasible clinical treatment strategy. We discovered that by transplanting immature photoreceptor cells, these cells can make new functional photoreceptors in the diseased retina, and restore some visual function. To translate our findings to a human therapy we need to isolate equivalent human photoreceptor precursors from stem cell cultures grown in the laboratory. New three-dimensional retinal culture methods can produce large numbers of new retinal cells. Our hypothesis is that photoreceptor cells generated from these stem cell cultures will be effective and safe for human therapy provided they are treated so that they reach exactly the right stage in a cell culture dish and provided only these correctly-staged cells are transplanted. One critical challenge therefore is developing methods to identify and collect correctly-staged human cells to transplant into the diseased retina. We will develop live cell sorting methods using antibodies that bind to special markers on the surface of the immature photoreceptor cells providing a tag to isolate them with. The efficacy of isolated cells for retinal repair will be tested in transplantation experiments in animal models of retinal disease. This study will develop cell isolation protocols for human photoreceptor precursor cells, which is a requisite step towards development of clinical trials for incurable retinal diseases causing blindness.

Technical Summary

Retinal degenerations with loss of photoreceptors are the leading cause of untreatable blindness in Europe. In 2006 we showed that photoreceptors can be transplanted into the adult retina and recently we have been able to provide the first definitive evidence of restoration of rod-mediated vision, following transplantation of rods into a model of stationary night blindness. Importantly we have also recently proved in the mouse model the concept of developing and utilising a cell surface biomarker panel to isolate transplantation-competent photoreceptor precursor cells from 3D embryonic stem cell retinal differentiation cultures. Whilst we have demonstrated that retinal repair by photoreceptor transplantation is feasible, for clinical application we need to develop protocols for purifying human photoreceptors from a renewable source. In this project we aim to identify a human cell surface biomarker panel and to develop robust methodologies for identification and purification of human rod and cone photoreceptor precursors from clinical grade human pluripotent stem cell cultures that will support the development of a clinical trial in retinal dystrophy patients.
To achieve this goal we will:
(1) Test the biomarkers we have identified in the mouse for labelling and isolation of human fetal photoreceptor precursor cells and immunophenotype human fetal photoreceptor cells;
(2) Define the biomarker profiles of human ESC-derived rod and cone photoreceptors by transcriptome analysis at sequential stages of maturation in human ESC-derived retinal cultures, and compare these profiles to transplantation competent mouse photoreceptor precursor cells;
(3) Evaluate combinations of identified biomarkers for purification of hESC-derived rod and cone photoreceptors;
(4) Evaluate biomarker selected hESC-derived cells in transplantation experiments;
(5) Develop robust biomarker panel-based isolation protocols and quality control assays for human photoreceptor precursors.

Planned Impact

Hereditary retinal disease and age related macular degeneration (AMD) leading to photoreceptor loss are the leading causes of untreatable blindness in the UK. There is currently no cure for these conditions, and available therapies at best, can provide a delay in disease progression to a minority of patients. Inherited retinal degenerations affect 1 in 3000 of the population whilst AMD affects 1 in 10 people over the age of 60 and its prevalence is increasing. In children more than 15% of blind registrations are due to inherited retina disease. These include children who are born without functional photoreceptors and who may have mutations in 1 of more than 100 different retinal disease genes, or have defects in unknown genes. Of these early onset conditions, those not amenable to gene therapy approaches, present a target group for whom photoreceptor cell transplantation may be first offered. There is currently no treatment option and these individuals face a lifetime of blindness. Beyond this patient group photoreceptor transplantation could be effective for a wide range of conditions resulting in photoreceptor cell death, although it may be necessary for transplants to be part of combined therapies in which abnormalities in additional tissues such as the retinal vasculature are also controlled. We have discovered that transplantation of immature photoreceptors improves vision in mouse models of retinal degeneration.The proposed project aims to builds on our discovery and to develop methods for isolation of equivalent human cells that could be used for stem cell therapy for the treatment of retinal diseases.

Publications

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Di Foggia V (2016) Induced Pluripotent Stem Cell Therapies for Degenerative Disease of the Outer Retina: Disease Modeling and Cell Replacement. in Journal of ocular pharmacology and therapeutics : the official journal of the Association for Ocular Pharmacology and Therapeutics

 
Description Genetics and Stem cell therapy for paediatric eye disease.
Amount £45,186 (GBP)
Organisation Great Ormond Street Hospital Children's Charity (GOSHCC) 
Sector Charity/Non Profit
Country United Kingdom
Start 04/2018 
End 03/2021
 
Description Great Ormond Street Hospital Children's Charity - iPSC facility at the UCL Great Ormond Street Institute of Child Health- Phase 1 2016
Amount £231,833 (GBP)
Funding ID 16DS27 
Organisation Great Ormond Street Hospital Children's Charity (GOSHCC) 
Sector Charity/Non Profit
Country United Kingdom
Start 10/2016 
End 09/2017
 
Description Great Ormond Street Hospital Children's Charity Research Leadership Award 2015
Amount £136,468 (GBP)
Funding ID V2816 
Organisation Great Ormond Street Hospital Children's Charity (GOSHCC) 
Sector Charity/Non Profit
Country United Kingdom
Start 04/2015 
End 03/2018
 
Description NIHR GOSH BRC Doctoral Training Support Fund March 2016 - Cell therapy for congenital retinal dystrophy: isolating and characterising developing human cone photoreceptors.
Amount £2,250 (GBP)
Funding ID R&D number 12DB10 
Organisation Great Ormond Street Hospital (GOSH) 
Department NIHR Great Ormond Street Biomedical Research Centre
Sector Academic/University
Country United Kingdom
Start 03/2016 
End 03/2017
 
Description Invited participant at National Eye Institute Audacious Goals Initiative (AGI) Workshop on Photoreceptor Regeneration and Integration 2015 
Organisation National Eye Institute (NEI)
Country United States 
Sector Academic/University 
PI Contribution Invited participant at National Eye Institute Audacious Goals Initiative (AGI) Workshop on Photoreceptor Regeneration and Integration, led by Dr. Paul Sieving, Director, NEI, Denver Colorado, USA May 2, 2015. http://www.nei.nih.gov/audacious/
Collaborator Contribution All participants contributed to NEI AGI Photoreceptor workshop white paper on photoreceptor regeneration
Impact All participants contributed to NEI AGI Photoreceptor workshop white paper on photoreceptor regeneration (in preparation)
Start Year 2015
 
Description The Lasker Foundation/International Retinal Research Foundation (IRRF) Initiative for Innovation in Vision Science 
Organisation Lasker Foundation
Country United States 
Sector Charity/Non Profit 
PI Contribution Invited speaker, discussant, session chair, author of summary document. The Lasker/IRRF Initiative is currently examining rapidly developing cutting-edge technologies that can be applied to re-establish light sensitivity and visual perception to the blind. Leaders in retinal degeneration, ocular genetics, electrophysiology and sensorimotor research, molecular biology, neuro-ophthalmology, nanotechnology and regenerative medicine, ophthalmic imaging and other disciplines relevant to the project met at two workshops held during the summer of 2013 and in 2014. The collaborative nature of this multi-disciplinary approach is designed to bridge the gaps between scientific disciplines and encourage the best minds to define the most creative solutions to daunting scientific problems; to design streamlined approaches that use all available tools; to accelerate discovery, and to facilitate translational research leading to new treatments to reverse retinal degenerative vision loss.
Collaborator Contribution As above
Impact Invited participant in The Lasker Foundation/International Retinal Research Foundation (IRRF) Initiative for Innovation in Vision Science 2013-14 Chaired by John Dowling of Harvard University. Invited speaker at Woods Hole, Massachusetts, USA July 8-9. Session Leader and Speaker "Stem Cells and Transplantation" at Howard Hughes Medical Institute, Janelia Farm Research Campus, Ashburne Virginia, US on March 23-26, 2014. Prepared Chapter 4 "Restoring Vision to the Blind: Stem Cells and Transplantation" and presented at Special Interest Group Symposium Association for Research in Vision and Ophthalmology (ARVO) Meeting, Denver, USA May 2015. ARVO published the Lasker report as a special issue of its online journal Translational Vision Science & Technology. The journal is listed in PubMed (Transl Vis Sci Technol. 2014 Dec; 3(7): 1.) and is open access, so the report is readily accessible to a global audience. Published online 2014 Dec 30. doi: 10.1167/tvst.3.7.1
Start Year 2013
 
Description 2015 & 2016 NIHR Great Ormond Street BRC Open Day : Stall and interactive stand on Seeing, Childhood eye diseases and New Treatments 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? Yes
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact 2015 NIHR Great Ormond Street BRC Open Day
Saturday 24 October 2015; UCL Institute of Child Health

In conjunction with the Bloomsbury Festival, the BRC hosted its annual Open Day on Saturday 24 October 2015. The aim of this day was to increase the general public's understanding of medical research, illustrate how it changes lives and inspire interest in a career in biomedical research. The day included a variety of events, including hand-on activities, seminars, posters and lab tours.

2016 NIHR Great Ormond Street BRC Open Day
Sat 10th October UCL Institute of Child Health
Public engagement to explain relevance and impact research. a stand with the topic "Super Vision: How do we see and can sight be restored?", provided an insight into the process of vision and the stem cell work in our lab, as well as how vision testing is done clinically. We offered several activities, such as a jigsaw of the retinal cell layers and a microscope to view retinal cells

We held a NIHR Great Ormond Street BRC Open Day in the Institute of Child Health with stands, activities, seminars, and laboratory tours that showcased multiple areas of research, with representation from each of the four NIHR Great Ormond Street BRC themes. Out of the 200+ attendees each year, 100% said they learned something about research, and feedback was very positive. Comments from visitors at the Open Day this year included, 'We were here from 12-4pm and loved it. Would have been even bet
Year(s) Of Engagement Activity 2015,2016
URL http://www.gosh.nhs.uk/great-ormond-street-brc-open-day-2016
 
Description 2017 Congress of the Association Pugliese Retinitis Pigmentosa: The point of therapy 16 December Bari, Italy. Scientific and patient, public engagement event 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Scientific, public, and patient engagement scientific event. Meeting organised by the Retinitis Pigmentosa Association of Apulia, Italy for patients and the clinical community to provide a update on scientific research on this disease, particularly on therapy news. The 1 day meeting with international speakers was attended by ophthalmologists, geneticists and families. Professor Sowden was an invited speaker. The conference was highlighted in local television news.
Year(s) Of Engagement Activity 2017
 
Description 3 page article in Pioneer magazine: All eyes on cell therapy. Summer 2018 Edition of Pioneer 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact 3 page article in Pioneer magazine: All eyes on cell therapy focussing on how our research on cell therapy could restore a child's sight
Pioneer magazine which is full of exclusive hospital news and is sent out twice a year to some of the supporters.
ttps://www.gosh.org/get-involved/philanthropy/impact-philanthropy/pioneer-online/pioneer-magazine
Year(s) Of Engagement Activity 2018
URL https://www.gosh.org/get-involved/philanthropy/impact-philanthropy/pioneer-online/pioneer-magazine
 
Description Article in the Breakthroughs in children's medicine (Great Ormond Street Hospital Charity magazine): Setting sights on curing childhood blindness 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Article in the Breakthroughs in children's medicine (Great Ormond Street Hospital Charity magazine on online) from the Sowden lab: Setting sights on curing childhood blindness.

The breakthrough magazine presents the unique achievements that have made Great Ormond Street Hospital one of the world's leading centres for treating childhood disease.
The sight and sound breakthrough guide focuses on some of the hospital's biggest advances in treating children with sight and hearing impairments.
Year(s) Of Engagement Activity 2018
URL https://www.gosh.org/what-we-do/research/breakthroughs-childrens-medicine
 
Description Biomedical Research Centre (BRC) iPSC Symposium to inaugurate the cell culture facility, chaired and organised by Professor Sowden 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Other audiences
Results and Impact A symposium to inaugurate the GOSHCC funded BRC iPSC cell culture facility for research on childhood disease with internal and external speakers. It was conducted to share research, meet potential collaborators, to engage with other institutions.

Chaired by Professor Sowden and an oral presentation was delivered by one member of our research group.
Year(s) Of Engagement Activity 2017
URL https://www.eventbrite.co.uk/e/gos-ich-ipsc-research-symposium-using-human-pluripotent-stem-cells-to...
 
Description CRISPR Genome Editing Congress Europe 2016. Berlin 24-26th October 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Facilitated networking with relevant Biotech companies open to future collaborations
http://crispr-europe.com/
Year(s) Of Engagement Activity 2016
URL http://crispr-europe.com/
 
Description Contributor to Grays Anatomy. Gray's Anatomy Chapter 'Development of the eye', 41st Edition of Gray's Anatomy Elsevier 2015. 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Contributor to Grays Anatomy. Gray's Anatomy Chapter 'Development of the eye', 41st Edition of Gray's Anatomy Elsevier 2015.

Contributor to Kaufman's Atlas of Mouse Development Supplement by Matthew Kaufman (original 1989), Elsevier, Editors, Richard Baldock, Jonathan Bard, Duncan Davidson, Gillian Morriss-Kay (In press)


TBC
Year(s) Of Engagement Activity 2015
 
Description Eye Patient Engagement Event; Speaker and Panel Member 5 September 2017, Edinburgh. MRC Genetics Unit 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Patients, carers and/or patient groups
Results and Impact As part of the MRC Human Genetics Unit's international scientific meeting, Eye Development & Degeneration Eye: From Genes to Therapy, a patient event was hosted, welcoming 40 patients suffering from vision-impairing conditions, as well as their family members and 4 guide dogs. Researchers and clinicians provided brief presentations about their current research on macular degeneration, eye abnormalities and retinal disease therapy using genome editing and stem cells. The talks were followed by a Question and Answer session with a panel of leading researchers and clinicians with an expertise in eye disorders. Professor Jane Sowden was a panel member and presenter.

The gratitude expressed by these visitors and the respect they had for the scientists championing their cause was humbling and rewarding. Such events allow scientists to take a step back and remind themselves why they chose to undertake their research in the first place - in order to discover the causes of, and ultimately, find treatments and cures for, conditions that affect the vision of many people worldwide.
Year(s) Of Engagement Activity 2017
URL https://www.ed.ac.uk/mrc-human-genetics-unit/news-and-events/news-2017/eye-engagement-2017
 
Description GOSH Research Trail 2016 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Patients, carers and/or patient groups
Results and Impact Organised a stand at the GOSH research trail, aimed at engaging GOSH patients and their families in research. The stand ran under the topic "Super Vision: How do we see?", and was aimed at younger children and included a big eye model for the children to take apart.
Year(s) Of Engagement Activity 2016
URL http://www.gosh.nhs.uk/research-and-innovation/nihr-great-ormond-street-brc/brc-events/spotlight-res...
 
Description Great Ormond Street Hospital (GOSH) Biomedical Research Centre (BRC) article about the BRC iPSC facility 
Form Of Engagement Activity A magazine, newsletter or online publication
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact An article was written for the GOSH magazine "Roundabout" about the opening of the new induced pluripotent stem cell (iPSC) facility in the Institute of Child Health (ICH). The article was also displayed on the GOSH website and will soon be on the BRC website.
Year(s) Of Engagement Activity 2017
URL http://www.gosh.nhs.uk/research-and-innovation/boost-stem-cell-research-gos
 
Description Hosted Portuguese delegation form the H2020 initiative "The Discoveries Centre for Regenerative and Precision Medicine" showcasing cell therapy and tissue engineering work at GOSICH to identify opportunities for interaction. 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Hosted Portuguese delegation form the H2020 initiative "The Discoveries Centre for Regenerative and Precision Medicine" showcasing cell therapy and tissue engineering work at GOSICH to identify opportunities for interaction.
Year(s) Of Engagement Activity 2018
 
Description Invited Speaker at Vision UK 2016 conference Expanding Horizons 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Patients, carers and/or patient groups
Results and Impact Vision UK is the leading annual conference for the eye health and sight loss sectors. Expanding Horizons pushes the boundaries for implementing the UK Vision Strategy nationally and ensuring engagement with organisations and influencers across the wider health and social care sectors.
I presented on The future in sight through stem cell research, in the stream Science and technology: saving sight and social inclusion, what next?
Presentations were followed by a Q&A for delegates to discuss the issues with the experts. The workshops were led by experts to facilitate engaging discussions and shape tangible actions for delegates to take away from the day.
Year(s) Of Engagement Activity 2016
URL http://www.ukvisionstrategy.org.uk/stream-4-science-and-technology
 
Description JS invited member of BBSRC Working Group 2018 : BBSRC Regenerative Biology and Stem Cell Working Group 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Other audiences
Results and Impact Member of BBSRC Regenerative Biology and Stem Cell Working Group (2018- ongoing)
Terms of Reference
The Regenerative Biology Working Group is undertaking the following activities:
o review BBSRC's current research and training portfolio in regenerative biology and stem cells
o advise on what portfolio analysis is required and should be conducted by BBSRC
o advise on the breadth and depth of the portfolio covered
o identify the strengths, gaps and opportunities within the portfolio
o identify potential challenges and barriers
Year(s) Of Engagement Activity 2018
 
Description London Stem Cell Network 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Professional Practitioners
Results and Impact Invited presentation at Workshop on Organoids and 3D Tissue Models on 24th January 2019 afternoon (14:00-19:00) organised by Discoveries Centre for Regenerative and Precision Medicine (https://thediscoveriesctr.eu) and the London Stem Cell Network (LSCN; https://lscn.crick.ac.uk).
Year(s) Of Engagement Activity 2018
 
Description MRC Developmental Cell Atlas Kick-off Meeting 28-29 Jan 2019 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Meeting to launch new projects funded by the MRC as part of the International Human Cell Atlas Consortium

https://mrc.ukri.org/news/browse/funding-boost-for-initiative-mapping-entire-human-body/

Presentation of our new collaborative project scEye-Map: Developmental trajectories of progenitor cell populations in the human eye at single cell resolution
Year(s) Of Engagement Activity 2019
URL https://mrc.ukri.org/news/browse/funding-boost-for-initiative-mapping-entire-human-body/
 
Description NIHR Great Ormond Street Hospital Biomedical Research Centre Family Fun Day 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact An open day where the general public could take part in fun hands on activities, meet researchers and discover how medical research at the NIHR Great Ormond Street Hospital Biomedical Research Centre is helping find treatments and cures for complex childhood conditions.
Year(s) Of Engagement Activity 2017
URL http://www.gosh.nhs.uk/research-and-innovation/nihr-gosh-brc/brc-events/nihr-great-ormond-street-hos...
 
Description Nature Research Round Table: Challenges in Ensuring hPSC Quality reservation (invited participant) 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Other audiences
Results and Impact Nature Research Round Table: Challenges in Ensuring hPSC Quality
Organised by Springer Nature and Stem Cell Technologies and academic leaders to discuss issues around IPSC quality for research and standards for ensuring publication integrity and quality.
Year(s) Of Engagement Activity 2018
 
Description Online BRC Newsletter Latest news September 2015 
Form Of Engagement Activity A magazine, newsletter or online publication
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact Work recently published in Stem Cells has shown that photoreceptor cells can be grown and purified in the lab before being transplanted into a mature host retina. This research, led by BRC-supported Professor Jane Sowden, suggests that cell replacement therapy involving the transplantation of new photoreceptor cells, isolated from retina grown in a dish, may be a possible treatment for blindness.

Raised profile of research
http://www.gosh.nhs.uk/research-and-innovation/gosh-biomedical-research-centre/brc-news
Year(s) Of Engagement Activity 2015
URL http://www.gosh.nhs.uk/how-purify-photoreceptors-retina-grown-dish
 
Description Participation in the Great Ormond Street Hospital (GOSH) Research Trail 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Patients, carers and/or patient groups
Results and Impact Public engagement event at GOSH to communicate research to patients and families. Activity on how the eye works and conditions affecting sight.
Year(s) Of Engagement Activity 2017
 
Description Participation in the Great Ormond Street Hospital (GOSH) Research Trail - Super stem cells 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Patients, carers and/or patient groups
Results and Impact Public engagement event at GOSH to communicate research to patients and families. Activity "Super stem cells - Find out where stem cells are found in your body and build a model of DNA from sweets"
Year(s) Of Engagement Activity 2007,2018
URL https://www.gosh.nhs.uk/our-research/our-research-infrastructure/nihr-gosh-brc/brc-events/research-t...
 
Description Public Engagement, YPAG meeting 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Patients, carers and/or patient groups
Results and Impact Young persons' advisory Group (YPAG) at Great Ormond Street Hospital: session to communicate research to YPAG and for them to advise on consent and patient information documents and study participation.
YPAG members are aged 8-21 and are interested in research, medicine and science.
Year(s) Of Engagement Activity 2018
 
Description Publication in press Restoring Vision using Stem Cells and Transplantation 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact Publication in press "Restoring Vision using Stem Cells and Transplantation"

Poster presentation at the XVIIIth International Retinal Degeneration Symposium (September 03-08, 2018 Killarney, Ireland) and submission of article for the proceedings volume of the RD2018 meeting. The volume, edited by the meeting organizers has an anticipated publication date in 2019. The book will be published in Springer's series, Advances in Experimental Medicine and Biology and will be indexed in PubMed.
Year(s) Of Engagement Activity 2018
URL http://www.rdmeeting.net