World Stem Cell Summit 2014 report part 1: research topics

Written by Norio Nakatsuji

Part 1 from the conference scene of the World Stem Cell Summit (WSCS) 2014 held in San Antonio (3—5 December, San Antonio, Texas)

World Stem Cell Summit (WSCS) 2014 was held in San Antonio, Texas, USA from December 3 to 5. Among the many international conferences in the field of stem cells and regenerative medicine, WSCS is distinct in focusing its efforts to serve as the meeting point by multi-sector communities of research, clinics, industry, regulation, policy making and ethics. All are aiming at advancing stem cell innovation and new therapies, under the banner of “connect, collaborate and cure.” As same as past years, presenters and attendees included not only researchers but also clinicians, funding agencies, government officials, industries and patients. Thus, many sessions focused on the clinical translation from basic research. Another important agenda were industrial and social aspects, and problems to be solved before realization of practical and sustainable stem cell-based therapies.

Research topics

Most research topics were directly connected to applications of stem cells. Among a variety of research topics, the most popular one this year was the clinical trial of mesenchymal stem cells (MSCs), which were obtained from variety of tissues and transplanted into a variety of diseased or injured tissues. Atta Behfar (Mayo Clinic) presented CHART (Congestive Heart Failure Cardiopoietic Regenerative Therapy) clinical trial data including population analysis of MSCs from bone marrow to identify lineage specified MSCs for cardiac repair. Joshua Hare (University of Miami) introduced on-going clinical trials and data on enhanced cardiac repair with co-transplantation of autologous MSCs and c-Kit-positive cardiac stem cells for congestive heart failure (CHF). Nathan Staff and Anthony Windebank (Mayo Clinic) showed MSCs transplantation for expressing cytokines and preventing neural cell degradation in Amyotrophic lateral sclerosis (ALS).

For many types of application, novel cell culture technologies need to be developed, including three-dimensional (3D) culture system for mass production, cell carrier devices for cell transplantation, and quality control of the production process. A session showed a few such innovations. The first is the utilization of a polysaccharides polymer which can support small particles such as cell aggregates suspended in the culture medium without gelation or increased viscosity, presented by Taito Nishino (Nissan Chemical Industries). Thus, it may be used for 3D suspension culture without need of physical stirring that easily damages fragile cells such as human pluripotent stem cells (hPSCs). The second is the micro-carrier made of biocompatible and clinically safe materials with the shape of small discs, SIS BioDiscs, presented by Rae Ritchie (Cook Biotech). They can be used for multi-layered cell carrier for efficient transplantation into target organs. The last presentation by Martha Rook (EMD Millipore) showed process innovation for scalable and Current Good Manufacturing Practice (cGMP)-grade bioreactor production system for stem cells such as MSCs. Large scale and high quality stem cell production is a key issue for reliable and affordable cell-based therapy.

There were two major topics in basic research. One was genome editing. George Church (Harvard Medical School and MIT Health Sciences and Technology) shared his results of mutant correction in cardiomyocytes with CRISPER-mediated genome editing, development of smaller Cas9 protein to enhance genome-editing efficiency, and epigenome editing to induce transcription activation. Hiromitsu Nakauchi (Stanford University and University of Tokyo) introduced highly efficient and reversible genome editing in variety of cells and animals with the piggyback system. Gary Smith (University of Michigan) shared his research in disease modeling with mutation-inserted human embryonic stem cells (hESCs), patient-derived and mutation-corrected induced pluripotent stem cells (iPSCs), and their depository. Thomas Zwaka (Icahn School of Medicine at Mt. Sinai) discussed removal of the D4Z4 repeat in Facioscapulohumeral muscular dystrophy (FSHD) by editing the telomere start region. He also showed exploring genes involving cell competition, but not stem cell renewal or differentiation. These genes may enhance survival of transplanted cells by competing against host cells.

Another major topic in basic research was organogenesis. Anthony Atala and Julie Allickson (Wake Forest University Medical Center) reported organogenesis with stem cells and biomaterials, such as decellularized tissue or 3D-printed synthetic scaffolds. They discussed their clinical trials of synthesized bladder and pre-clinical study of generated organs with autologous stem cells. Anthony Atala explained that amniotic and placental stem cells can differentiate into all three germ layer-derived cell types. Doris Taylor (Texas Heart Institute, St. Luke’s Episcopal Hospital) spoke about heart organogenesis with hESC-derived cells and decellularized tissue. Koji Kuchiishi (Cyfuse Biomedical) introduced their cell-spheroid assembling technologies to construct 3D organs. George Church (Harvard Medical School and MIT Health Sciences and Technology) introduced development of organ-on-chip with organoides. Hiromitsu Nakauchi (Stanford University and University of Tokyo) shared his progress of generating human organs in animals by generating chimeric pig embryos lacking key genes for organogenesis with human iPSCs, in which iPSC-derived cells can win the developmental competition.

Authors: Kouichi Hasegawa, Takashi Asada, Shintaro Sengoku and Norio Nakatsuji (Institute for Integrated Cell-Materials Sciences, Kyoto University, Kyoto, Japan)

Disclosure: This work was partially supported by a grant from the New Energy and Industrial Technology Development Organization. N. Nakatsuji is a founder and shareholder of a hESC/iPSC-related company, ReproCELL, Inc.

The full conference scene is scheduled to be published in Volume 10 Issue 4 of Regenerative Medicine.