A permanent cure for HIV infection remains elusive due to the virus’s ability to hide away in latent reservoirs. But now, in new research published in the journal Molecular Therapy, scientists at the Lewis Katz School of Medicine (LKSOM)  at Temple University and the University of Pittsburgh show that they can excise HIV DNA from the genomes of living animals to eliminate further infection. They are the first to perform the feat in three different animal models, including a “humanized” model in which mice were transplanted with human immune cells and infected with the virus. The team is the first to demonstrate that HIV-1 replication can be completely shut down and the virus eliminated from infected cells in animals with a powerful gene editing technology known as CRISPR/Cas9. The new work builds on a previous proof-of-concept study that the team published in 2016

“Our new study is more comprehensive,” Dr. Hu said. “We confirmed the data from our previous work and have improved the efficiency of our gene editing strategy. We also show that the strategy is effective in two additional mouse models, one representing acute infection in mouse cells and the other representing chronic, or latent, infection in human cells.”

In the new study, the team genetically inactivated HIV-1 in transgenic mice, reducing the RNA expression of viral genes by roughly 60 to 95 percent, confirming their earlier findings. They then tested their system in mice acutely infected with EcoHIV, the mouse equivalent of human HIV-1.

“During acute infection, HIV actively replicates,” Dr. Khalili explained. “With EcoHIV mice, we were able to investigate the ability of the CRISPR/Cas9 strategy to block viral replication and potentially prevent systemic infection.” The excision efficiency of their strategy reached 96 percent in EcoHIV mice, providing the first evidence for HIV-1 eradication by prophylactic treatment with a CRISPR/Cas9 system.

The work was led by Wenhui Hu, MD, PhD, currently Associate Professor in the Center for Metabolic Disease Research  at LKSOM; Kamel Khalili, PhD, Laura H. Carnell Professor and Chair of the Department of Neuroscience, Director of the Center for Neurovirology, and Won-Bin Young, PhD. Dr. Young was Assistant Professor in the Department of Radiology at the University of Pittsburgh School of Medicine at the time of the research. Dr. Young recently joined LKSOM.

Source: https://medicine.temple.edu/

Scientists are harnessing a new way to turn cancer cells into potent, anti-cancer agents. In the latest work from the lab of Khalid Shah, MS, PhD, at Brigham and Women’s Hospital, a founding member of the Mass General Brigham healthcare system, investigators have developed a new cell therapy approach to eliminate established tumors and induce long-term immunity, training the immune system so that it can prevent cancer from recurring. The team tested their dual-action, cancer-killing vaccine in an advanced mouse model of the deadly brain cancer glioblastoma, with promising results.

“Our team has pursued a simple idea: to take cancer cells and transform them into cancer killers and vaccines,” said corresponding author Khalid Shah, MS, PhD, director of the Center for Stem Cell and Translational Immunotherapy (CSTI) and the vice chair of research in the Department of Neurosurgery at the Brigham and faculty at Harvard Medical School and Harvard Stem Cell Institute (HSCI). “Using gene engineering, we are repurposing cancer cells to develop a therapeutic that kills tumor cells and stimulates the immune system to both destroy primary tumors and prevent cancer.”

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Sanatech Seed, the Japanese start-up behind the launch of the world’s first direct consumption genome-edited tomato, says the variety is the first of several it plans to develop with enhanced nutritional benefits. The company’s Sicilian Rouge High GABA tomato was developed using cutting edge CRISPR/Cas9 gene editing technology. It contains high levels of Gamma-AminoButyric Acid (GABA), an amino acid believed to aid relaxation and help lower blood pressure.

According to Shimpei Takeshita, president of Sanatech Seed and chief innovation officer of Pioneer EcoScience, the exclusive distributor of the tomato, it contains four to five times more GABA than a regular tomato.

“This tomato represents an easy and realistic way in which consumers can improve their daily diet,” he told delegates during a session on how to breed better tomatoes at this year’s Global Tomato Congress.

Takeshita said the reason for choosing both the Sicilian Rouge variety and the GABA trait was their high level of acceptance by consumers. “Sicilian Rouge is a popular tomato, and consumers are already used to buying other products with a high GABA content so we felt it was important to introduce them to the technology in a way that was already familiar to them,” he explained.

Dr Hiroshi Ezura, CTO of Sanatech Seed, told the congress that CRISPR/Cas9 is simpler and easier to handle than other gene editing techniques, making it ideal for developing crops with enhanced nutritional characteristics. Rules in Japan allow products developed using gene editing to be sold providing the necessary approval has been sought from the regulatory agencies. “With GMOs you need to produce a lot of data in order to get regulatory approval by the government, while with gene editing, you still need to notify the government but the amount of data you have to produce is a lot lower,” Ezura explained. There have been widespread marketing campaigns in Japan to educate consumers about the difference between GMOs and gene-edited crops, so there is a higher level of understanding and acceptance of these products than in other parts of the world.

Source: http://www.fruitnet.com

A new gene therapy could eventually provide an alternative treatment for Fuchs’ endothelial corneal dystrophy, a genetic eye disease that affects roughly one in 2,000 people globally. Currently, the only treatment is corneal transplant, a major surgery with associated risks and potential complications.

“When you do a transplant you make a huge difference for that person, but it’s a big deal for the patient with lots of visits, lots of eye drops, lots of co-pays, and if you had a medical treatment that did not require surgery, that would be great,” says Bala Ambati, a research professor at the University of Oregon who led an eight-year study involving the development of the gene therapy. “Not only could it help patients who need a transplant, but it could also help a lot of other people who could have used that (corneal) tissue.”

For the study in the journal eLife, investigators focused on a rare, early-onset version of the disease and carried out the research in mice. They used CRISPR-Cas9, a powerful tool for editing genomes, to knock out a mutant form of a protein that is associated with the disease.

Fuchs’ dystrophy occurs when cells in the corneal layer called the endothelium gradually die off and stressed cells produce structures known as guttae. These cells normally pump fluid from the cornea to keep it clear, but when they die, fluid builds up, the cornea gets swollen, and vision becomes cloudy or hazy.

“We were able to stop this toxic protein expression and study it in a mouse model,” says coauthor Hiro Uehara, a senior research associate in the Ambati lab. “We confirmed that (in mice who received it), our treatment was able to rescue loss of corneal endothelial cells, reduce guttata-like structures, and preserve the corneal endothelial cell pump function.”

Corneal cells are non-reproducing, meaning you’re born with all of the cells you will ever have, Ambati says. One of the challenges of the study involved using CRISPR gene editing technology on such cells, a process that is technically difficult.

Uehara developed an innovative workaround that increases the utility of the CRISPR technology and could eventually lead to treatments for other diseases involving non-reproducing cells, including some neurologic diseases, immune diseases, and certain genetic disorders affecting the joints. The study marks the first time that researchers have applied the technique, called start codon disruption, to non-reproducing cells.

Source: https://accelerate.uoregon.edu/

Biopharmaceutical company CRISPR Therapeutics has entered into a strategic research, development and commercialization partnership with cancer-focused Nkarta. The new collaboration will be geared toward advancing CRISPR/Cas9 gene-edited cell therapies for certain cancers.

In a statement on the collaboration, the companies state “their complementary cell therapy engineering and manufacturing capabilities” will join forces to advance “the development of a novel NK+T product candidate harnessing the synergies of the adaptive and innate immune systems.” Financial details of the agreement were not publicly disclosed.

According to terms of the agreement, both CRISPR Therapeutics and Nkarta plan to jointly develop and commercialize up to two CAR NK cell product candidates. One candidate will target the CD70 tumor antigen, while no specific target has been set for the additional product. Nkarta has obtained a license to CRISPR gene-editing technology under the agreement. This license will allow Nkarta to edit up to five gene targets using “an unlimited number” of the company’s own NK cell therapy products.

Additionally, the two companies will share equally the research and development costs as well as global profits related to the products born from the collaboration. While Nkarta will retain global rights to a product candidate using a CRISPR Therapeutics’ gene editing target but not developed through the collaboration, Nkarta will provide CRISPR Therapeutics milestone payments as well as royalties on all net sales of the non-collaboration product.

There is a three-year exclusivity on the new agreement, according to the announcement of the collaboration. Overall, the exclusivity agreement covers the research, development as well as commercialization of allogeneic, gene-edited, and donor-derived NK cells and NK+T cells. “This collaboration broadens the scope of our efforts in oncology cell therapy, and expands our efforts to discover and develop novel cancer therapies for patients,” according to a statement made by CRISPR Therapeutics’ Chief Executive Officer (CEO), Samarth Kulkarni, Ph.D.

“Uniting the best-in-class gene editing solution and allogeneic T cell therapy expertise of CRISPR with Nkarta’s best-in-class CAR NK cell therapy platform will be a major advantage to advancing the next wave of transformative cancer cell therapies,” said Nkarta’s CEO, Paul J. Hastings, in a statement. Hastings added that the partnership will enable the company to harness CRISPR’s deep knowledge of CD70 biology as well as experience in the clinical development of allogeneic T cell candidates, which may ultimately “deliver innovative treatments to patients that much faster.”

https://www.biospace.com/

A humbling lesson of science is that, even when it comes to many of humanity’s most brilliant inventions, nature got there first. The 2020 selection for the Nobel Prize in Chemistry goes to two scientists who share credit for identifying and developing a revolutionary method of genome editing — one that has allowed researchers to modify and investigate the genomes of microbial, plant and animal cells with an ease, precision and effectiveness that would have been unfathomable even a decade ago. Yet the technology that came out of their work, revolutionary as it is, springs from an innovation that first evolved in bacteria, probably more than a billion years ago, and went unnoticed until recently.

Emmanuelle Charpentier (right) and Jennifer Doudna (left) have been awarded the 2020 Nobel Prize in Chemistry for their development of CRISPR/Cas9 genetic editing.

Emmanuelle Charpentier of the Max Planck Unit for the Science of Pathogens Institute for Infection Biology and Jennifer Doudna of the University of California, Berkeley have been recognized for their work on CRISPR/Cas9 genome editing — a technique routinely called CRISPR for short and often referred to as “genetic scissors.” This award marks the first time that two women have been award a Nobel Prize for science.

In a seminal 2012 paper, Charpentier and Doudna showed that key components of the ancient immune system found in bacteria and archaea could be retooled to edit DNA, to essentially “rewrite the code of life,” as the Nobel committee put it this morning.

In the eight years since, the discovery has transformed the life sciences, making genome editing commonplace in laboratories around the world. It has enabled researchers to probe the functions of genes at will, pushing the field of molecular biology ahead by leaps and bounds; to innovate new methods of plant breeding; and to develop promising new gene therapies, some now in clinical trials, for conditions such as sickle cell disease.

The Nobel committee’s selection will undoubtedly be greeted as controversial because of well-publicized disputes about the intellectual property associated with CRISPR. Virginijus Šikšnys of Vilnius University in Lithuania independently developed the idea of using these genetic features of bacteria as a genome-editing tool at about the same time as Charpentier and Doudna, and he has sometimes been honored alongside them. Two other scientists, Feng Zhang of the Massachusetts Institute of Technology and George Church of Harvard University, are also often credited as early co-discoverers and developers of CRISPR technology, and their exclusion will fuel arguments. However, no one in the scientific community would dispute that Charpentier and Doudna’s work laid the foundation for CRISPR’s prolific and game-changing use today.

Source: https://www.quantamagazine.org/

Using induced pluripotent stem cells produced from the skin of a patient with a rare, genetic form of insulin-dependent diabetes called Wolfram syndrome, researchers transformed the human stem cells into insulin-producing cells and used the gene-editing tool CRISPR-Cas9 to correct a genetic defect that had caused the syndrome. They then implanted the cells into lab mice and cured the unrelenting diabetes in those mice.

The findings, from researchers at Washington University School of Medicine in St. Louis, suggest the CRISPR-Cas9 technique may hold promise as a treatment for diabetes, particularly the forms caused by a single gene mutation, and it also may be useful one day in some patients with the more common forms of diabetes, such as type 1 and type 2.

Wolfram syndrome is caused by mutations to a single gene, providing the researchers an opportunity to determine whether combining stem cell technology with CRISPR to correct the genetic error also might correct the diabetes caused by the mutation. Patients with Wolfram syndrome develop diabetes during childhood or adolescence and quickly require insulin-replacement therapy, requiring insulin injections multiple times each day. Most go on to develop problems with vision and balance, as well as other issues, and in many patients, the syndrome contributes to an early death.

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Researchers at Washington University School of Medicine in St. Louis have transformed stem cells into insulin-producing cells. They used the CRISPR gene-editing tool to correct a defect that caused a form of diabetes, and implanted the cells into mice to reverse diabetes in the animals. Shown is a microscopic image of insulin-secreting beta cells (insulin is green) that were made from stem cells produced from the skin of a patient with Wolfram syndrome.

“This is the first time CRISPR has been used to fix a patient’s diabetes-causing genetic defect and successfully reverse diabetes,” said co-senior investigator Jeffrey R. Millman, PhD, an assistant professor of medicine and of biomedical engineering at Washington University. “For this study, we used cells from a patient with Wolfram syndrome because, conceptually, we knew it would be easier to correct a defect caused by a single gene. But we see this as a stepping stone toward applying gene therapy to a broader population of patients with diabetes.”

The study is published online in the journal Science Translational Medicine.

Source: https://medicine.wustl.edu/

HIV treatment has come a long way over the years, due in large part to antiretroviral drugs that stop the HIV virus from replicating in the body. This gives the immune system a chance to repair itself and stop further damage. Thanks to these amazing advances, HIV is no longer the death sentence that it was in previous decades. However, antiretrovirals only keep HIV at bay for as long as they’re taken. Defaulting on the drugs means that the HIV virus comes back. Even worse, it can cause patients to build up resistance to the antiretrovirals so that they do not work so effectively in the future. In other words, there’s still room for improvement when it comes to treatment. Fortunately, researchers from the University of California — San Diego School of Medicine are poised to provide help, courtesy of a new genetic-sequencing approach that could possibly provide a “kill switch” to clear out dormant HIV reservoirs inside cells.

“The most exciting part of this discovery has not been seen before,” Tariq Rana, professor of pediatrics and genetics at UC San Diego School of Medicine, said in a statement. “By genetically modifying a long non-coding RNA, we prevent HIV recurrence in T cells and microglia upon cessation of antiretroviral treatment, suggesting that we have a potential therapeutic target to eradicate HIV and AIDS.”

The work is based on the discovery of a recently emerged gene that appears to regulate HIV replication in immune cells, including macrophages, microglia, and T cells. The team refers to this as HIV-1 Enchanced LncRNA (HEAL), and it is elevated in people with HIV. By using CRISPR-Cas9 gene editing, their work suggests that it could stop HIV from recurring in the event that antiretroviral treatment is stopped.

“This has the potential for [being a] cure but, [we’ll] have to wait for animal studies,” Rana told Digital Trends. As for the next steps, Rana said that future studies “will determine if turning this regulator HEAL off can remove viral reservoirs, which are the key source for viral rebound when therapies are discontinued.” A paper describing the work was recently published in the journal mBio.

Source: https://mbio.asm.org/
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https://www.digitaltrends.com/

Some viruses, no matter how hard we try, remain resistant to vaccines. Now, researchers are using a different method, gene editing, as a way to make cells immune to mankind’s most difficult viruses. Led by Dr. Justin Taylor, a team at the Fred Hutchinson Cancer Research Center has targeted four infections for which there’s no protective vaccine: HIV, influenza, the Epstein-Barr virus (EBV) and respiratory syncytial virus (RSV).

The researchers used CRISPR/Cas9 technology to modify B cells, a class of white blood cells that produce antibodies to protect us from diseases. By coding the cells with genes that create specific antibodies, the team was able to make them immune without the use of a vaccine.

The researchers tested the method in both human cells in a test tube and in living mice. On average, about 30 percent of the cells produced the desired antibody. Taylor said that the mice remained protected for 83 days following the procedure, an important benchmark given that patients who receive stem cell transplants can have weakened immune systems for three to six months. To be clear, Taylor doesn’t have anything against traditional vaccination. “Vaccines are great,” he said. “I wish we had more of them.”

Instead, Taylor thinks the gene editing method could work one day for diseases where we don’t have a vaccine. It may help patients who are immuno-compromised, meaning their bodies can no longer fight infections, as well as older patients whose bodies aren’t as receptive to vaccines. Gene-edited immunity might also be used to protect people faster than can be done with traditional vaccines, which could be useful during unexpected outbreaks.

Taylor’s team included Fred Hutch researchers and co-authors Howell Moffett, Carson Harms, Kristin Fitzpatrick, Marti Tooley and Jim Boonyaratanakornkit. The results will be published in the journal Science Immunology.

Source: https://www.fredhutch.org/
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Wake Forest Institute for Regenerative Medicine (WFIRM) scientists have figured out a better way to deliver a DNA editing tool to shorten the presence of the editor proteins in the cells in what they describe as a “hit and run” approach.

CRISPR (clustered regularly interspaced short palindromic repeats) technology is used to alter DNA sequences and modify gene function. CRISPR/Cas9 is an enzyme that is used like a pair of scissors to cut two strands of DNA at a specific location to add, remove or repair bits of DNA. But CRISPR/Cas9 is not 100 percent accurate and could potentially cut unexpected locations, causing unwanted results.

“One of the major challenges of CRISPR/Cas9 mRNA technologies is the possibility of off-targets which may cause tumors or mutations,” said Baisong Lu, Ph.D, assistant professor of regenerative medicine at WFIRM and one of the lead authors of the paper. Although other types of lentivirus-like bionanoparticles (LVLPs) have been described for delivering proteins or mRNAs, Lu said, “the LVLP we developed has unique features which will make it a useful tool in the expanding genome editing toolbox.”

To address the inaccuracy issue, WFIRM researchers asked the question: Is there a way to efficiently deliver Cas9 activity but achieve transient expression of genome editing proteins? They tested various strategies and then took the best properties of two widely used delivery vehicles – lentivirus vector and nanoparticles – and combined them, creating a system that efficiently packages Cas9 mRNA into LVLPs, enabling transient expression and highly efficient editing.

Lentiviral vector is a widely used gene delivery vehicle in research labs and is already widely used for delivering the CRISPR/Cas9 mRNA technology for efficient genome editing. Nanoparticles are also being used but they are not as efficient in delivery of CRISPR/Cas9.

“By combining the transient expression feature of nanoparticle-delivery strategies while retaining the transduction efficiency of lentiviral vectors, we have created a system that may be used for packaging various editor protein mRNA for genome editing in a ‘hit and run’ manner,” said Anthony Atala, M.D., director of WFIRM and co-lead author of the paper. “This system will not only improve safety but also avoid possible immune response to the editor proteins, which could improve in vivo gene editing efficiency which will be useful in research and clinical applications.”

The WFIRM team published its findings in a paper published recently in the journal  Nucleic Acids Research.

Source: https://school.wakehealth.edu/