Volume 5, Issue 2: March 2016
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Inside This Issue

  1. Break Through
  2. Pressing Matters
  3. Meeting Center
  4. Awards Spotlight
  5. Molecular Link
  6. On the Horizon
  7. InSite
  8. Get Involved

President's Message


Michel Sadelain, MD, PhD

Mary Dean, JD, CAE

Dear ASGCT Members,

On behalf of the ASGCT Executive Committee, we are pleased to introduce several new Members to the Editorial leadership of The Vector: Dr. Guohua Yi will serve as Associate Editor of The Vector and Dr. Phillip Doerfler will serve as Junior Associate Editor. Both ASGCT Members were selected from a competitive group of highly qualified ASGCT Members and will be serving a one-year term. Along with the Editor of The Vector, Dr. Zhongya Wang, these newly elected members will strive to bring the most cutting-edge and timely scientific content to our newsletter.  If you have any suggestions for Vector topics and content, I encourage you to send them to ASGCT’s Project Manager, Emily Hutmacher.

The Society’s 19th Annual Meeting is just around the corner and we hope you will be joining us in Washington, DC, for what will undoubtedly be a week filled with spectacular science, memorable presentations, and plenty of opportunities for networking. Please check out the ASGCT Annual Meeting website for the latest program updates and logistical information.

The ASGCT Board of Directors, under the recommendations of the Advisory Council, has selected the 2016 Award Recipients. Please join us in congratulating these stellar ASGCT Members.

The Outstanding New Investigator Award (ONI) recognizes ASGCT Members who are newly independent researchers. The 2016 Award recipients are:

The Outstanding Achievement Award (OAA) recognizes an ASGCT Member who has achieved a pioneering research success, a specific high impact accomplishment, or a lifetime of significant scientific contributions to the fields of gene and/or cell therapy. The 2016 recipient is Seppo Yla-Herttuala, MD, PhD, FESC, of the University of Eastern Finland.

The Sonia Skarlatos Public Service Award (PSA) recognizes a person or group that has consistently fostered and enhanced the field of genetic and/or cellular therapy. This year, the award is presented to Katherine P. Ponder, MD, of the Washington University School of Medicine.

The ONI and OAA winners will deliver plenary lectures at the ASGCT 19th Annual Meeting in Washington, DC. The PSA will be given prior to the OAA plenary lecture during the Annual Meeting. Please be sure to join us in acknowledging and celebrating these outstanding ASGCT Members!

As a closing reminder, don’t forget to register for the Annual Meeting and pre-meeting programs! We are looking forward to another record breaking year Washington, DC!

We look forward to seeing you in Washington, DC this May!

Sincerely,

Michel Sadelain, MD, PhD
ASGCT President

Mary Dean, JD, CAE
ASGCT Executive Director

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Letter From the Editor

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Breaking Through

A dual AAV system enables the Cas9-mediated correction of a metabolic liver disease in newborn mice

Nat Biotechnol. 34:334-8, (March 2016)
doi: 10.1038/nbt.3469
http://www.nature.com/nbt/journal/v34/n3/full/nbt.3469.html

Yang Yang                      Lili Wang
Peter Bell                       Deirdre McMenamin
Zhenning He                 John White
Hongwei Yu                   Chenyu Xu
Hiroki Morizono             Kiran Musunuru
Mark L. Batshaw           James M. Wilson

Summary written by:
Lili Wang, PhD
University of Pennsylvania, Perelman School of Medicine

Many genetic liver diseases, including ornithine transcarbamylase (OTC) deficiency, present in newborns with repeated, often lethal, metabolic crises. Adeno-associated virus (AAV) neonatal gene therapy in this setting would require multiple vector administrations to maintain the therapeutic effects because the non-integrating genome is lost as developing hepatocytes proliferate. Correcting the defective gene by genome editing in the young mice could solve this problem. Therefore, newborn liver may be an ideal setting for gene correction using CRISPR/Cas9, a powerful genome editing tool consisting of the Cas9 nuclease and a single guide RNA (sgRNA). A key challenge in using the CRISPR-Cas9 system to correct a mutation in vivo is delivering the three components of the system (Cas9, sgRNA and donor DNA) into the same cell in a way that is safe and efficient.

Yang et. al describe in “A dual AAV system enables the Cas9-mediated correction of a metabolic liver disease in newborn mice”  a strategy using an AAV vector with high liver tropism (AAV8) to correct the point mutation in newborn spfash mice using Cas9 enzyme from Staphylococcus aureus (SaCas9). An animal model of OTC deficiency, the male sparse fur ash (spfash) mouse, has a G-to-A point mutation at the donor splice site at the end of exon 4 of the OTC gene, which leads to abnormal splicing and a 20-fold reduction in OTC mRNA and protein. In this work, the authors developed a two-vector approach to incorporate all 3 components of CRISPR/Cas9 into AAV. Vector 1 expresses the SaCas9 gene from a liver-specific TBG promoter, while vector 2 contains the sgRNA1 sequence expressed from the U6 promoter and the 1.8 kb donor OTC DNA sequence. Spfash pups were injected intravenously on postnatal day 2 with mixtures of vector 1 and vector 2 and subsequently evaluated for indel (insertion and deletion) formation and functional correction of the spfash mutation. Following genome editing (3 and 8 weeks), indels were detected by deep sequencing in 31% of OTC alleles, and homology directed repair (HDR)-based correction of the G-to-A mutation was observed in 10% of OTC alleles. Liver sections were analyzed by immunohistochemistry for OTC expression showing 15% OTC-positive cells at 3 weeks and 13% at 8 weeks. Direct measurements of OTC enzyme activity from liver homogenates and OTC mRNA from total cellular RNA from liver revealed similarly high levels of correction in treated animals. The authors further assess the impact of gene correction on the clinical manifestations of OTC deficiency by evaluating the tolerance of spfash mice to a one-week course of high-protein diet. Spfash mice treated with the genome editing vectors had significantly lower plasma ammonia levels and showed a survival improvement as compared to untreated spfash mice.

Encouraged by the results in newborn spfash mice, Yang et. al conducted similar studies in adult spfash mice at two vector doses. Surprisingly, between 3 to 4 weeks after treatment with low-dose vectors, the animals became sick and by week 5 all had to be euthanized. This toxicity was more severe in the high-dose animals, requiring euthanasia at 2 weeks. Further analyses showed dose-dependent diminished ureagenesis compared to control animals. Deep sequencing of the targeted region of OTC revealed remarkably high frequencies of indels (34 - 50%) but low levels of gene correction. Among the indels, the adult-treated animals had higher frequencies of large deletions, with 6.5% extending into the adjacent exon, which could ablate the residual function in the hypomorphic OTC gene in spfash mice. The authors speculate that different non-homologous end joining (NHEJ) and/or HDR mechanisms may exist in nondividing adult hepatocytes versus dividing newborn hepatocytes that affects the quality of the DNA repair response.

In summary, this study provides convincing evidence for efficacy in an authentic animal model of a lethal human metabolic disease following in vivo genome editing using CRISPR-Cas9 system.

Directed evolution of a recombinase that excises the provirus of most HIV-1 primary isolates with high specificity

Nat. Biotechnol. 2016 Feb 22.
doi: 10.1038/nbt.3467
http://www.nature.com/nbt/journal/vaop/ncurrent/full/nbt.3467.html

Janet Karpinski                             Karl Hackmann
Ilona Hauber                                 Evelin Schrock
Jan Chemnitz                                Josephine Abi-Ghanem
Carola Schafer                              M. Teresa Pisabarro
Maciei Paszkowski-Rogacz        Vineeth Surendranath
Deboyoti Chakraborty                  Axel Schambach
Niklas Beschorner                       Christoph Lindner
Helga Hofmann-Sieber               Jan van Lunzen
Ulrike C. Lange                             Joachim Hauber
Adam Grundhoff                            Frank Buchholz

Summary written by:
Phillip A. Doerfler, PhD
St. Jude Children's Research Hospital

AIDS remains a global health problem. Efforts on preventing the transmission of HIV have been improving through the years but the rate of infection is largely unchanged. Anti-retroviral therapies (ART) have gone through many iterations and the latest generation of ART effectively controls the viremia associated with HIV infection. However, latent viral genomes in CD4+ quiescent memory T-cells can be reactivated and generate new viral particles capable of spreading the infection. It is therefore imperative for HIV+ individuals to be on lifelong ART to diminish the risk of shedding replication-competent HIV. Despite the positive outlook HIV+ patients have on ART, it is by no means a cure, as ART does not eliminate the integrated HIV genome and thus, interruption of therapy will lead to rapid rebound of viremia from latent reservoirs. To excise the provirus of HIV+ cells is therefore the ultimate goal of developing a treatment for AIDS. Genome editing using targeted nucleases is one possible manner of treatment but carries the risk of off-target effects. The laboratory of Frank Buchholz has been evaluating recombinases to efficiently remove HIV provirus, and in their latest paper published in Nature Biotechnology they used a directed evolution approach to develop a Cre-type recombinase capable of removing the provirus that results from infection with HIV from multiple clades. ART, gene and cell therapies for HIV infection continue to improve, and with the addition of recombinases the next generation of successful HIV therapies may be on the horizon.

Karpinski and colleagues first identified a target sequence, named Brec target region, that has 90% conservation across clades A, B, and C of HIV-1, which may be a viable region to design recombinases to target. Due to the conservation of the target sequence, the authors speculate the region is less likely to mutate than other regions of the HIV genome. The broad-range recombinase (Brec1) target region (loxBTR) does differ substantially from the standard Cre/loxP site (23 out of 34 bases). The authors developed a recombinase library and identified greater than 100 clones that had recombination properties capable of recombining loxBTR but not loxP. It is possible that an HIV isolate does mutate the loxBTR site, but four common mutations that occur in the LTR of HIV isolates were evaluated and it was found that Brec1 effectively recombines these mutations.

In HeLa and human PM1 T-lymphocyte cell lines that possess a stably integrated HIV genome, the Brec1 recombinase was effective in eliminating the HIV provirus. Circular excision product was observed exclusively in cell cultures that were transduced with a lentiviral or retroviral vector encoding Brec1 compared to a control vector that did not contain Brec1. These are encouraging results for a potential ex vivo approach to treat HIV infection, and in anticipation of clinical translation, the authors evaluated the safety of using Brec1 in model systems. First, the authors evaluated the safety in cell lines, primary CD4+ T cells as well as CD34+ stem cells. They constitutively expressed Brec1 in Jurkat cells by lentiviral gene transfer and found that  cell growth and cell cycle progression were not affected by Brec1 expression. Similarly, the authors demonstrated that constitutive expression in primary CD4+ T-cells is likewise unaffected in immune activation, function, and apoptosis. Further, the potential of  the CD34+ hematopoietic cells to develop into expected multiple lineages was also not affected. Secondly, the human genome was scanned for possible endogenous loxBTR sequences. Six such regions were identified, but in an E. coli system, no recombination occurred. Lastly, Brec1 was constitutively expressed in a mouse model for more than a year and no apparent toxicity resulted from long-term expression of the recombinase. These data on the safety of the Brec1 system are very promising for a clinical product.

The strongest evidence for the feasibility of a recombinase-based approach in excising HIV provirus has been shown in the experiment of humanized mice xenotransplantation. Irradiated NSG mice received a transplant of CD34+ hematopoietic cells transduced with a lentiviral vector containing Brec1. Human cell engraftment was evaluated after 16 weeks. Mice with >10% human lymphocytes were then challenged with HIV. Twenty weeks after challenge, the viremia of mice that received Brec1 lentivirus- transduced CD34+ cells were barely above the level of PCR detection. Similarly, immunohistochemistry of spleen sections revealed a lack of HIV p24+ cells. In total, Brec1 demonstrated a profound capacity to eliminate HIV provirus.

The work by Karpinski et al. is a thorough demonstration on the effectiveness of recombinases to treat HIV infection. In cell lines, primary cells, CD34+ cells, animal models and xenotransplants, the authors show safety and efficacy of Brec1 to excise the HIV provirus and give hope for more effective treatments to combat HIV.

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Pressing Matters

  Read highlights from the latest issue of Molecular Therapy, the official journal of
  ASGCT.

  Also, explore the open access, online-only companion journals to Molecular Therapy:

   Click here to visit the Molecular Therapy page on Nature Publishing Group's
   website.

                                                 

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Meeting Center

19th Annual Meeting Housing and Registration
Register for the Annual Meeting, Pre-Meeting Workshops, and the special Genome Editing Symposium by visiting the Annual Meeting website.

There are a limited number of rooms still available at the Marriott Wardman Park Hotel or the Omni Shoreham Hotel. Book your room today by visiting the Annual Meeting housing website.

19th Annual Meeting Evening Reception and Washington, DC Attractions
ASGCT will host a closing night reception at the Newseum, on Friday, May 6, 2016, from 8:00pm to 10:00pm. The reception will feature live music, drinks, and passed hors d'oeuvres. Free shuttles will be provided between the Marriott Wardman Park Hotel and the Newseum. The reception is a ticketed event costing $25/person and tickets can be purchased when registering for the Annual Meeting here.

While in Washington, DC, discover inspiring museums, powerful monuments and memorials. A diverse, cosmopolitan world capital, DC invites visitors to explore its charming neighborhoods, sample its hip shops and restaurants and experience its vibrant nightlife. For information on attractions, dining, and tours, please visit the ASGCT Annual Meeting website.

Genome Editing Special Symposium - May 4, 2016
New this year, ASGCT is excited to present a special symposium focusing on the concepts and clinical applications of genome editing. This symposium will take place during the 19th Annual Meeting on Wednesday, May 4, 2016, from 8:00am to 12:15pm. Anyone attending the Annual Meeting may attend this symposium at no additional cost. Please note that if you are NOT attending the Annual Meeting and would just like to attend this symposium, you must register via the ASGCT website.

For more details, view the program schedule for the Genome Editing Special Symposium.

Commercialization Workshop - May 3, 2016
Subjects that have been covered in previous Commercialization Workshops include payer perspectives on clinical benefit and cost-effectiveness, pricing and reimbursement strategies, manufacturing requirements, intellectual property, venture capital investments, pharma partnering, case studies, and much more.  In 2016 some of  these topics will be developed further in addition to new subjects such as differences in US and European regulatory pathways, strategies for successfully turning a TTP into a product label, and the role of patients and patient advocacy groups within the commercialization and regulatory environment.

For more details, visit the program schedule for the Commercialization Workshop.

Grant Writing Workshop - May 3, 2016
The Grant Writing Workshop will provide new investigator, post-doctoral fellow, and graduate student attendees with a solid foundation on writing their first RO1 grants; the review process, including common questions reviewers ask; and examples of grants from gene and cell therapy that have been successful or unsuccessful during the review process with commentary on why the grants were or were not successful at obtaining funding.

View the program schedule for the Grant Writing Workshop and register here.

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Awards Spotlight

2016 ASGCT Award Winners

ASGCT is honored to recognize Dr. Seppo Yla-Herttuala of the University of Eastern Finland as the recipient of the 2016 Outstanding Achievement Award. Dr. Yla-Herttuala has made a lifetime of significant contributions to the gene and cell therapy field including notable work in the areas of vascular disease and glioblastoma. Dr. Yla-Herttuala will give a plenary lecture at ASGCT’s 19th Annual Meeting on Friday, May 6, 2016 from 10:45 am to 11:45 am.

Dr. Katherine Ponder is the recipient of this year’s Sonia Skarlatos, PhD, Public Service Award. Dr. Ponder is acknowledged for her longtime service and contributions to ASGCT, along with her mentorship of new investigators. Dr. Ponder will be presented with her award at the ASGCT 19th Annual Meeting immediately preceding the Outstanding Achievement Award symposium on Friday, May 6, 2016, at 10:45 am.

The Outstanding New Investigator Awards are given as recognition for scientists conducting original research in basic science, technology development or clinical translation. Each of the following recipients was recommended by at least two Society Members who provided written justification for each researcher to be considered. The Outstanding New Investigator award recipients will deliver a plenary lecture at ASGCT’s 19th Annual Meeting on Thursday, May 5, 2016, from 1:30 pm to 3:30 pm.

Recipients of the 2016 ASGCT Outstanding New Investigators Award include:

ASGCT congratulates each of its award winners, and is appreciative for their continued contributions to the field of gene and cell therapy.

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Molecular Link

ASGCT Job Bank
As a student or postdoctoral fellow, the ASGCT Job Bank allows you to search for gene and cell therapy positions and post your resume so employers can search for you. Members can post positions and view resumes at a reduced rate. Take advantage of this area to grow your professional development. Below are three recent job postings to the ASGCT online job bank, your link to the latest career opportunities within gene and cell therapy.

Click here to visit the ASGCT Job Bank, and view the complete list of current career opportunities.

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On the Horizon

Save the Date for the ASGCT 19th Annual Meeting!
The 19th Annual Meeting will be held at the Marriott Wardman Park Hotel in Washington, DC, May 4 -7, 2016. ASGCT is proud to present plenary speakers David R. Liu, PhD, Alain Fischer, MD, and Theodore Friedmann, MD. Read more about the 19th Annual Meeting plenary speakers here.

19th Annual Meeting Important Dates

Upcoming ASGCT Joint Events
ASGCT is proud to partner with the following organizations for joint programming:

ASGCT will participate in a guest symposium at the AAI 2016 Immunology meeting, held from May 13 - 17, 2016, in Seattle, WA. Details for the symposium are as follows:

Genetic Engineering of T Cells
Monday, May 16, 2016
10:15 AM – 12:15 PM
Seattle, WA, USA
Click here for more information.

Additionally, ASGCT is co-organizing a Workshop on Clinical Translation with the ISSCR, held the day before the ISSCR 2016 Annual Meeting on June 21, 2016. This full-day Workshop will feature international experts on cellular  therapy with real-life experience moving translational projects into the clinic. Details for the Workshop are as follows:

ASGCT and ISSCR Workshop on Clinical Translation
Tuesday, June 21, 2016
San Francisco, CA, USA
Click here for more information.

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InSITE

Industry News

Follow Us
Follow ASGCT on Twitter and like our Facebook page for up-to-date publications, news in the field of gene and cell therapy, and updates on the 19th Annual Meeting.

Join ASGCT's Official LinkedIn group to connect with the best in the field, discuss key issues, grow your personal network, and post open jobs.

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Get Involved

Become a Member
Renew your Membership for 2016 through the ASGCT website and join us for another exciting year in the growing field of gene and cell therapy! Do you have colleagues interested in joining ASGCT? Send them information on becoming a member and encourage your colleagues to turn their interest into involvement.

Volunteer to Serve on an ASGCT Committee
ASGCT is excited to offer its Active Members the ability to self-nominate or submit recommendations of individuals to serve on committees within ASGCT. To submit a recommendation or to volunteer to serve on an ASGCT Committee, please complete this form.

Submit Your Press Release
In order to increase publicity for gene and cell therapy, ASGCT would like to issue press releases for clinical trials results as they emerge in the field. Our hope is that by increasing exposure of the positive results in the field, we can grow public awareness of gene and cell therapy. ASGCT welcomes written communications from partnering institutions and ASGCT  Member researchers sharing the commitment to advancing the treatment of human diseases. Please visit the ASGCT website to submit your press release.

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