Stem cell therapy for animals has seen breakthroughs

Stem cell therapy is increasingly becoming a more mainstream form of medicine. Usually applied to humans, the use of this regenerative treatment is now also being extended to animals including cats and dogs. Regenerative medicine, particularly stem cell treatment has seen many advancements in recent years with some groundbreaking studies coming to light.

Taking the cells from bone marrow, umbilical cords, blood or fat, stem cells can grow to become any kind of cell and the treatment has seen many successes in animals. The regenerative therapy has been useful particularly for treatment of spinal cord and bone injuries as well as problems with tendons, ligaments and joints.

Expanded Potential Stem Cells (EPSCs) have been obtained from pig embryos for the first time. The cells offer groundbreaking potential for studying embryonic development and producing transnational research in genomics and regenerative medicine, biotechnology and agriculture.

The cells have been efficiently derived from pig preimplantation embryos and a new culture medium developed in Hong Kong and Cambridge enabled researchers from the FLI to establish permanent embryonic stem cell lines. The cells have been discovered in a collaboration between research groups from the Institute of Farm Animal Genetics at the Friedrich-Loeffler-Institut (FLI) in Mariensee, Germany, the Wellcome Trust Sanger Institute in Cambridge, UK and the University of Hong Kong, Li Ka Shing Faculty of Medicine, School of Biomedical Sciences.

Embryonic stem cells (ESC) are derived from the inner cells of very early embryos, the so-called blastocysts. Embryonic stem cells are all-rounders and can develop into various cell types of the body in the culture dish. This characteristic is called pluripotency. Previous attempts to establish pluripotent embryonic stem cell lines from farm animals such as pigs or cattle have resulted in cell lines that have not really fulfilled all properties of pluripotency and were therefore called ES-like.

Dr Monika Nowak-Imialek of the FLI said: Our porcine EPSCs isolated from pig embryos are the first well-characterized cell lines worldwide. EPSCs great potential to develop into any type of cell provides important implications for developmental biology, regenerative medicine, organ transplantation, disease modelling and screening for drugs.

The stem cells can renew themselves meaning they can be kept in culture indefinitely, and also show the typical morphology and gene expression patterns of embryonic stem cells. Somatic cells have a limited lifespan, so these new stem cells are much better suited for long selection processes. It has been shown that these porcine stem cell lines can easily be modified with new genome editing techniques such as CRISPR/Cas, which is particularly interesting for the generation of porcine disease models.

The EPSCs have a high capacity to develop not only into numerous cell types of the organism, but also into extraembryonic tissue, the trophoblasts, making them very unique and lending them their name. This capacity could prove valuable for the future promising organoid technology, where organ-like small cell aggregations are grown in 3D aggregates that can be used for research into early embryo development, various disease models and testing of new drugs in petri dishes. In addition, the authors were able to show that trophoblast stem cells can be generated from their porcine stem cells, offering a unique possibility to investigate functions or diseases of the placenta in vitro.

A major hurdle to using neural stem cells derived from genetically different donors to replace damaged or destroyed tissues, such as in a spinal cord injury, has been the persistent rejection of the introduced material (cells), necessitating the use of complex drugs and techniques to suppress the hosts immune response.

Earlier this year, an international team led by scientists at University of California San Diego School of Medicine successfully grafted induced pluripotent stem cell (iPSC)-derived neural precursor cells back into the spinal cords of genetically identical adult pigs with no immunosuppression efforts. The grafted cells survived long-term, displayed differentiated functionality and caused no tumours.

The researchers also demonstrated that the same cells showed similar long-term survival in adult pigs with different genetic backgrounds after only short course use of immunosuppressive treatment once injected into injured spinal cord.

Senior author of the paper Martin Marsala, MD, professor in the Department of Anesthesiology at UC San Diego School of Medicine said: The promise of iPSCs is huge, but so too have been the challenges. In this study, weve demonstrated an alternate approach.

We took skin cells from an adult pig, an animal species with strong similarities to humans in spinal cord and central nervous system anatomy and function, reprogrammed them back to stem cells, then induced them to become neural precursor cells (NPCs), destined to become nerve cells. Because they are syngeneic genetically identical with the cell-graft recipient pig they are immunologically compatible. They grow and differentiate with no immunosuppression required.

Co-author Samuel Pfaff, PhD, professor and Howard Hughes Medical Institute Investigator at Salk Institute for Biological Studies, said: Using RNA sequencing and innovative bioinformatic methods to deconvolute the RNAs species-of-origin, the research team demonstrated that pig iPSC-derived neural precursors safely acquire the genetic characteristics of mature CNS tissue even after transplantation into rat brains.

NPCs were grafted into the spinal cords of syngeneic non-injured pigs with no immunosuppression finding that the cells survived and differentiated into neurons and supporting glial cells at all observed time points. The grafted neurons were detected functioning seven months after transplantation.

Then researchers grafted NPCs into genetically dissimilar pigs with chronic spinal cord injuries, followed by a transient four-week regimen of immunosuppression drugs again finding long-term cell survival and maturation.

Marsala continued: Our current experiments are focusing on generation and testing of clinical grade human iPSCs, which is the ultimate source of cells to be used in future clinical trials for treatment of spinal cord and central nervous system injuries in a syngeneic or allogeneic setting.

Because long-term post-grafting periods between one and two years are required to achieve a full grafted cells-induced treatment effect, the elimination of immunosuppressive treatment will substantially increase our chances in achieving more robust functional improvement in spinal trauma patients receiving iPSC-derived NPCs.

In our current clinical cell-replacement trials, immunosuppression is required to achieve the survival of allogeneic cell grafts. The elimination of immunosuppression requirement by using syngeneic cell grafts would represent a major step forward said co-author Joseph Ciacci, MD, a neurosurgeon at UC San Diego Health and professor of surgery at UC San Diego School of Medicine.

Other recent advancements include the advancement toward having a long-lasting repair caulk for blood vessels. A new method has been for generating endothelial cells, which make up the lining of blood vessels, from human induced pluripotent stem cells. When endothelial cells are surrounded by a supportive gel and implanted into mice with damaged blood vessels, they become part of the animals blood vessels, surviving for more than 10 months.

The research was carried out by stem cell researchers at Emory University School of Medicine and could form the basis of a treatment for peripheral artery disease, derived from a patients own cells.

Young-sup Yoon, MD, PhD, who led the team, said: We tried several different gels before finding the best one. This is the part that is my dream come true: the endothelial cells are really contributing to endogenous vessels.

When cells are implanted on their own, many of them die quickly, and the main therapeutic benefits are from growth factors they secrete. When these endothelial cells are delivered in a gel, they are protected. It takes several weeks for most of them to migrate to vessels and incorporate into them.

Other groups had done this type of thing before, but the main point is that all of the culture components we used would be compatible with clinical applications.

This research is particularly successful as previous attempts to achieve the same effect elsewhere had implanted cells lasting only a few days to weeks, using mostly adult stem cells, such as mesenchymal stem cells or endothelial progenitor cells. The scientists also designed a gel to mimic the supportive effects of the extracellular matrix. When encapsulated by the gel, cells could survive oxidative stress inflicted by hydrogen peroxide that killed unprotected cells. The gel is biodegradable, disappearing over the course of several weeks.

The scientists tested the effects of the encapsulated cells by injecting them into mice with hindlimb ischemia (restricted blood flow in the leg), a model of peripheral artery disease.

After 4 weeks, the density of blood vessels was highest in mice implanted with gel-encapsulated endothelial cells. The mice were nude, meaning genetically immunodeficient, facilitating acceptance of human cells.

The scientists found that implanted cells produce pro-angiogenic and vasculogenic growth factors. In addition, protection by the gel augmented and prolonged the cells ability to contribute directly to blood vessels. To visualise the implanted cells, they were labelled beforehand with a red dye, while functioning blood vessels were labelled by infusing a green dye into living animals. Implanted cells incorporated into vessels, with the highest degree of incorporation occurring at 10 months.

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Sixteen months ago, Bob Masterson began a Holy Name Medical Center clinical trial that he hoped would grow more arteries to restore blood flow to his legs sothe wounds on his toeswould heal. If it failed, he risked the possibility of amputation.

Masterson had aa 67% chance of getting the FDA-fast-tracked Pluristem Therapy placenta stem cell injections instead of getting a placebo.

In essence what were injecting is going to recruit the development of blood vessels, cells that are involved in the healing of wounds, said Dr. John Rundback, director of the Interventional Institute at the medical center.

When getting the procedure last year,Mastersonsays he had no idea whether he was getting the placebo or the real thing, but the results from regular visits to the hospital seem to indicate it was the latter.

Doctors want to improve National Institutes of Healthnumbers, whichfind half of all amputees die within five years, with new therapies that could come from the clinical trial of 246 patients at six hospitals.

Masterson says hes grateful for the results but doesnt consider the apparent reversal of his condition a miracle.

But, I see it as a progress in medicine,he said. Cause over my years, Ive seen a lot of people, especially with us who have diabetes, losing their limbs like it was nothing. And this gives them hope.

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LONDON--(BUSINESS WIRE)--Vertex Pharmaceuticals Incorporated (NASDAQ: VRTX) today announced that SYMDEKO (tezacaftor/ivacaftor and ivacaftor) is reimbursed in Australia for people with cystic fibrosis (CF) ages 12 years and older who are homozygous for the F508del mutation or who have one copy of the F508del mutation and another responsive residual function (RF) mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. People with CF who have one copy of the F508del mutation and another responsive RF mutation in the CFTR gene will have access to a medicine for the cause of their CF for the first time. In addition, ORKAMBI (lumacaftor/ivacaftor) is now also reimbursed for the treatment of children with CF ages 2 to 5 who have two copies of the F508del mutation in the CFTR gene. Patients over the age of 6 have already been able to access ORKAMBI in Australia since October 2018.

Following previously received positive recommendations from the Pharmaceutical Benefits Advisory Committee (PBAC), eligible patients in Australia will be able to access both medicines immediately, and the medicines will be listed on the Pharmaceutical Benefits Scheme (PBS) from December 1st.

We are pleased that SYMDEKO and ORKAMBI will be made available immediately to eligible cystic fibrosis patients in Australia. We appreciate that the PBAC has recognized the value of these medicines to patients and thank the Department of Health and the Minister for Health in Australia for their strong engagement and collaboration to finalize the agreement, said Ludovic Fenaux, Senior Vice President, Vertex International.

Vertexs CF medicines are reimbursed in 17 countries around the world including Austria, Denmark, Germany, the Republic of Ireland, Italy, the Netherlands, Sweden and the U.S.

About CFCystic Fibrosis (CF) is a rare, life-shortening genetic disease affecting approximately 75,000 people worldwide. CF is a progressive, multi-system disease that affects the lungs, liver, GI tract, sinuses, sweat glands, pancreas and reproductive tract. CF is caused by a defective and/or missing CFTR protein resulting from certain mutations in the CFTR gene. Children must inherit two defective CFTR genes one from each parent to have CF. While there are many different types of CFTR mutations that can cause the disease, the vast majority of all people with CF have at least one F508del mutation. These mutations, which can be determined by a genetic test, or genotyping test, lead to CF by creating non-working and/or too few CFTR proteins at the cell surface. The defective function and/or absence of CFTR protein results in poor flow of salt and water into and out of the cells in a number of organs. In the lungs, this leads to the buildup of abnormally thick, sticky mucus that can cause chronic lung infections and progressive lung damage in many patients that eventually leads to death. The median age of death is in the early 30s.

About SYMDEKO (tezacaftor/ivacaftor) in combination with ivacaftorSome mutations result in CFTR protein that is not processed or folded normally within the cell, and that generally does not reach the cell surface. Tezacaftor is designed to address the trafficking and processing defect of the CFTR protein to enable it to reach the cell surface and ivacaftor is designed to enhance the function of the CFTR protein once it reaches the cell surface.

Mutations in the CFTR gene, responsive to SYMDEKO, that are currently registered in Australia include F508del/f and P67L, R117C, L206W, R352Q, A455E, D579G, 711+3AG, S945L, S977F, R1070W, D1152H, 2789+5GA, 3272-26AG, 3849+10kbCT, E56K, R74W, D110E, D110H, E193K, E831X, F1052V, K1060T, A1067T, F1074L and D1270N.

About ORKAMBI (lumacaftor/ivacaftor) and the F508del mutationIn people with two copies of the F508del mutation, the CFTR protein is not processed and trafficked normally within the cell, resulting in little-to-no CFTR protein at the cell surface. Patients with two copies of the F508del mutation are easily identified by a simple genetic test. Lumacaftor/ivacaftor is a combination of lumacaftor, which is designed to increase the amount of mature protein at the cell surface by targeting the processing and trafficking defect of the F508del-CFTR protein, and ivacaftor, which is designed to enhance the function of the CFTR protein once it reaches the cell surface.

About VertexVertex is a global biotechnology company that invests in scientific innovation to create transformative medicines for people with serious diseases. The company has three approved medicines that treat the underlying cause of cystic fibrosis (CF) a rare, life-threatening genetic disease and has several ongoing clinical and research programs in CF. Beyond CF, Vertex has a robust pipeline of investigational medicines in other serious diseases where it has deep insight into causal human biology, such as sickle cell disease, beta thalassemia, pain, alpha-1 antitrypsin deficiency, Duchenne muscular dystrophy and APOL1-mediated kidney diseases.

Founded in 1989 in Cambridge, Mass., Vertex's global headquarters is now located in Boston's Innovation District and its international headquarters is in London, UK. Additionally, the company has research and development sites and commercial offices in North America, Europe, Australia and Latin America. Vertex is consistently recognized as one of the industry's top places to work, including nine consecutive years on Science magazine's Top Employers list and top five on the 2019 Best Employers for Diversity list by Forbes.

Special Note Regarding Forward-Looking Statements

This press release contains forward-looking statements as defined in the Private Securities Litigation Reform Act of 1995, including, without limitation, the statements in the second and third paragraphs of the press release. While Vertex believes the forward-looking statements contained in this press release are accurate, these forward-looking statements represent the company's beliefs only as of the date of this press release and there are a number of risks and uncertainties that could cause actual events or results to differ materially from those expressed or implied by such forward-looking statements. Those risks and uncertainties include, among other things, that data from the company's development programs may not support registration or further development of its compounds due to safety, efficacy or other reasons, and other risks listed under Risk Factors in Vertex's annual report and subsequent quarterly reports filed with the Securities and Exchange Commission and available through the company's website at http://www.vrtx.com. Vertex disclaims any obligation to update the information contained in this press release as new information becomes available.

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Vertex Announces Reimbursement of Cystic Fibrosis Medicines SYMDEKO (tezacaftor/ivacaftor and ivacaftor) for Eligible Patients Ages 12 and Older, and...

Oct. 21, 2019 05:00 UTC

SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)-- Genentech, a member of the Roche Group (SIX: RO, ROG; OTCQX: RHHBY), today announced that the Phase III IMbrave150 study, evaluating Tecentriq (atezolizumab) in combination with Avastin (bevacizumab) as a treatment for people with unresectable hepatocellular carcinoma (HCC) who have not received prior systemic therapy, met both of its co-primary endpoints demonstrating statistically significant and clinically meaningful improvements in overall survival (OS) and progression-free survival (PFS) compared with standard-of-care sorafenib.

Safety for the combination of Tecentriq and Avastin was consistent with the known safety profiles of the individual medicines, with no new safety signals identified. Data from the IMbrave150 study will be presented at an upcoming medical meeting.

We are very pleased with the results of our study testing the combination of Tecentriq and Avastin, which marks the first treatment in more than a decade to improve overall survival in people with unresectable hepatocellular carcinoma who have not received prior systemic therapy, said Levi Garraway, M.D., Ph.D., chief medical officer and head of Global Product Development. HCC is a major cause of death globally and particularly in Asia, making this study an important step in our mission of addressing unmet medical needs for patients around the world. We will submit these data to global health authorities as soon as possible. Our hope is to bring a new treatment to people with this aggressive disease who currently have limited options.

In July 2018, the U.S. Food and Drug Administration (FDA) granted Breakthrough Therapy Designation (BTD) for Tecentriq in combination with Avastin in HCC based on data from an ongoing Phase Ib trial.

Genentech has an extensive development program for Tecentriq, including multiple ongoing and planned Phase III studies, across lung, genitourinary, skin, breast, gastrointestinal, gynecological and head and neck cancers. This includes studies evaluating Tecentriq both alone and in combination with other medicines.

About the IMbrave150 study

IMbrave150 is a global Phase III, multicenter, open-label study of 501 people with unresectable HCC who have not received prior systemic therapy. People were randomized 2:1 to receive the combination of Tecentriq and Avastin or sorafenib. Tecentriq was administered intravenously, 1200 mg on day 1 of each 21-day cycle, and Avastin was administered intravenously, 15 mg/kg on day 1 of each 21-day cycle. Sorafenib was administered by mouth, 400 mg twice per day, on days 1-21 of each 21-day cycle. People received the combination or the control arm treatment until unacceptable toxicity or loss of clinical benefit as determined by the investigator. Co-primary endpoints were OS and PFS by independent review facility (IRF) per Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1). Secondary efficacy endpoints included overall response rate (ORR), time to progression (TTP) and duration of response (DoR), as measured by RECIST v1.1 (investigator-assessed [INV] and IRF) and HCC mRECIST (IRF), as well as patient-reported outcomes (PROs), safety and pharmacokinetics.

About hepatocellular carcinoma

According to the American Cancer Society, it is estimated that more than 42,000 Americans will be diagnosed with liver cancer in 2019. Liver cancer incidence has more than tripled since 1980 and HCC accounts for approximately 75% of all liver cancer cases in the United States. HCC develops predominantly in people with cirrhosis due to chronic hepatitis (B and C) or alcohol consumption, and typically presents at an advanced stage where there are limited treatment options.

About the Tecentriq and Avastin combination

There is a strong scientific rationale to support further investigation of Tecentriq plus Avastin in combination. Avastin, in addition to its anti-angiogenic effects, may further enhance Tecentriqs ability to restore anti-cancer immunity by inhibiting vascular endothelial growth factor (VEGF)-related immunosuppression, promoting T-cell tumor infiltration and enabling priming and activation of T-cell responses against tumor antigens.

About Tecentriq (atezolizumab)

Tecentriq is a monoclonal antibody designed to bind with a protein called PD-L1. Tecentriq is designed to bind to PD-L1 expressed on tumor cells and tumor-infiltrating immune cells, blocking its interactions with both PD-1 and B7.1 receptors. By inhibiting PD-L1, Tecentriq may enable the re-activation of T cells. Tecentriq may also affect normal cells.

About Avastin (bevacizumab)

Avastin is a prescription-only medicine that is a solution for intravenous infusion. It is a biologic antibody designed to specifically bind to a protein called VEGF that plays an important role throughout the lifecycle of the tumor to develop and maintain blood vessels, a process known as angiogenesis. Avastin is designed to interfere with the tumor blood supply by directly binding to the VEGF protein to prevent interactions with receptors on blood vessel cells. The tumor blood supply is thought to be critical to a tumors ability to grow and spread in the body (metastasize).

Tecentriq U.S. Indications

Tecentriq is a prescription medicine used to treat adults with:

A type of bladder and urinary tract cancer called urothelial carcinoma. Tecentriq may be used when your bladder cancer:

The approval of Tecentriq in these patients is based on a study that measured response rate and duration of response. Continued approval for this use may depend on the results of an ongoing study to confirm benefit.

A type of lung cancer called non-small cell lung cancer (NSCLC).

A type of breast cancer called triple-negative breast cancer (TNBC).

Tecentriq may be used with the medicine paclitaxel protein-bound when your breast cancer:

The approval of Tecentriq in these patients is based on a study that measured the amount of time until patients disease worsened. Continued approval for this use may depend on results of an ongoing study to confirm benefit.

A type of lung cancer called small cell lung cancer (SCLC).

It is not known if Tecentriq is safe and effective in children.

Important Safety Information

What is the most important information about Tecentriq?

Tecentriq can cause the immune system to attack normal organs and tissues and can affect the way they work. These problems can sometimes become serious or life threatening and can lead to death.

Patients should call or see their healthcare provider right away if they get any symptoms of the following problems or these symptoms get worse.

Tecentriq can cause serious side effects, including:

Getting medical treatment right away may help keep these problems from becoming more serious. A healthcare provider may treat patients with corticosteroid or hormone replacement medicines. A healthcare provider may delay or completely stop treatment with Tecentriq if patients have severe side effects.

Before receiving Tecentriq, patients should tell their healthcare provider about all of their medical conditions, including if they:

Patients should tell their healthcare provider about all the medicines they take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

The most common side effects of Tecentriq when used alone include:

The most common side effects of Tecentriq when used in lung cancer with other anti-cancer medicines include:

The most common side effects of Tecentriq when used in triple-negative breast cancer with paclitaxel protein-bound include:

Tecentriq may cause fertility problems in females, which may affect the ability to have children. Patients should talk to their healthcare provider if they have concerns about fertility.

These are not all the possible side effects of Tecentriq. Patients should ask their healthcare provider or pharmacist for more information. Patients should call their doctor for medical advice about side effects.

Report side effects to the FDA at 1-800-FDA-1088 or http://www.fda.gov/medwatch.

Report side effects to Genentech at 1-888-835-2555.

Please visit http://www.Tecentriq.com for the Tecentriq full Prescribing Information for additional Important Safety Information.

Avastin is approved for:

Avastin in combination with paclitaxel, pegylated liposomal doxorubicin or topotecan, is approved to treat platinum-resistant recurrent epithelial ovarian, fallopian tube or primary peritoneal cancer (prOC) in women who received no more than two prior chemotherapy treatments.

Avastin, either in combination with carboplatin and paclitaxel or with carboplatin and gemcitabine, followed by Avastin alone, is approved for the treatment of patients with platinum-sensitive recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer (psOC)

Possible serious side effects

Everyone reacts differently to Avastin therapy. So, its important to know what the side effects are. Although some people may have a life-threatening side effect, most do not. Their doctor will stop treatment if any serious side effects occur. Patients should contact their health care team if there are any signs of these side effects.

Side effects seen most often

In clinical studies across different types of cancer, some patients experienced the following side effects:

Avastin is not for everyone

Patients should talk to their doctor if they are:

Patients should talk with their doctor if they have any questions about their condition or treatment.

Report side effects to the FDA at 1-800-FDA-1088 or http://www.fda.gov/medwatch.

Report side effects to Genentech at 1-888-835-2555.

For full Prescribing Information and Boxed WARNINGS on Avastin please visit http://www.avastin.com.

About Genentech in personalized cancer immunotherapy

For more than 30 years, Genentech has been developing medicines with the goal to redefine treatment in oncology. Today, were investing more than ever to bring personalized cancer immunotherapy (PCI) to people with cancer. The goal of PCI is to provide each person with a treatment tailored to harness his or her own immune system to fight cancer. Genentech is currently studying more than 10 cancer immunotherapy medicines across 70 clinical trials alone or in combination with other medicines. In every study we are evaluating biomarkers to identify which people may be appropriate candidates for our medicines. For more information visit http://www.gene.com/cancer-immunotherapy.

About Genentech

Founded more than 40 years ago, Genentech is a leading biotechnology company that discovers, develops, manufactures and commercializes medicines to treat patients with serious and life-threatening medical conditions. The company, a member of the Roche Group, has headquarters in South San Francisco, California. For additional information about the company, please visit http://www.gene.com.

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Newswise Bioengineers at the University of California San Diego are a step closer to making CAR T-cell therapy safer, more precise and easy to control. They developed a system that allows them to select where and when CAR T cells get turned on so that they destroy cancer cells without harming normal cells.

The system requires two keysthe drug Tamoxifen and blue lightto activate CAR T cells to bind to their targets. Just one key keeps the cells inactive. Researchers tested their system on live cell cultures as a proof of concept. Their next step is to do tests on tumors in mice.

With our technology, we can have better control over CAR T-cell treatments in patients and potentially avoid non-specific targeting of organs and nonmalignant tissues, said UC San Diego bioengineering professor Peter Yingxiao Wang, a co-senior author of the study. Researchers recently published their work in ACS Synthetic Biology.

Chimeric antigen receptor (CAR) T-cell therapy is a promising new approach to treat cancer. It involves collecting a patients T cells and genetically engineering them to express special receptors on their surface that can recognize an antigen on targeted cancer cells. The engineered T cells are then infused back into the patient to find and attack cells that have the targeted antigen on their surface.

This approach has worked well for some types of blood cancer and lymphoma. But a major problem, Wang explains, is that it can work too well. Many targeted cancer antigens are also expressed on healthy cells, which can lead to attack of essential organs such as the heart, lungs or liver. This risk is known as on-target, off-tumor toxicity and can be life-threatening to patients receiving CAR T-cell therapy.

Traditional CAR T cells are always on, meaning they continuously express an antigen-targeting receptor. Our approach was to engineer T cells that can be selectively turned on to express the receptor at a specific location and time frame, Wang said.

Wang and colleagues engineered T cells that are only activated following a sequence of two inputs: treatment with the small molecule drug Tamoxifen, followed by exposure to short pulses of low intensity blue light. The chance to have accidental activation will be extremely low because you need both inputs at the same time. The drug primes the cells, and the light allows us to precisely guide where they get activated, Wang said.

Initially, the CAR T cells are in standby mode. In order to turn on, two particular proteins (one outside the nucleus and one inside) need to bind together in order to trigger expression of the antigen-targeting receptor. The drug Tamoxifen first binds to one of these proteins and helps it move into the nucleus, where the other protein awaits. Blue light then induces both proteins to combine. Any cells treated with the drug but not exposed to blue light remain in standby mode.

The light cannot penetrate deeply in the body, so Wang envisions that this approach could be useful for treating cancers on the skin, head and neck. He is now looking to collaborate with clinicians to do in vivo testing to treat melanoma.

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Paper title: An AND-gated drug and photoactivatable Cre-loxP system for spatiotemporal control in cell-based therapeutics. Co-authors include Molly E. Allen, Jeyan Thangaraj, Philip Kyriakakis, Yiqian Wu, Ziliang Huang, Phuong Ho, Yijia Pan, Praopim Limsakul and Xiangdong Xu, UC San Diego; and Wei Zhou, Chongqing Cancer Hospital, China.

This work was supported by grants from the National Institutes of Health, the Galvanizing Engineering in Medicine program under the Institute of Engineering in Medicine and Altman Clinical and Translational Research Institute (ACTRI) at UC San Diego, the American Cancer Society, and the National Heart, Lung, and Blood Institute (NHLBI).

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Burn specialists at Massachusetts General Hospital are the first in the world to successfully use live-cell, genetically engineered pig skin to temporarily close a burn wound in a human patient but the breakthrough has drawn opposition from People for the Ethical Treatment of Animals.

The ultimate holy grail is the end to the worlds organ shortage, that would be the holy grail, this has come at a time when genetic editing is really hot and what we could do in years, we can do in weeks, said Dr. Jeremy Goverman of the MGH Sumner Redstone Burn Service.

The pig tissue, known as xenoskin, was transplanted directly onto a human burn wound next to a larger piece of human skin.

Five days later, surgeons removed the human skin and the pig tissue to see that both grafts were stuck to the wound bed and were indistinguishable from each other.

Following the procedure, the burn wound was then treated further with a skin graft taken from the patients thigh. Healing progressed well and the patient will return to work soon.

The goal is to replace skin with xenoskin thats like it enough that it doesnt get rejected, said Goverman. Down the line we hope to ultimately create something thats not temporary.

The biggest push now is actually decreasing your donor site size and decreasing how much skin you have to harvest, said Goverman.

Patients who receive this type of graft typically have severe burns that require more than one operation and about a week of hospitalization.

Weve been using dressing like this in the past, we just havent been able to use anything with live cells. The live cells have all the appropriate factors that could really stimulate and regenerate and close our wounds for us, said Goverman.

MGH worked with Boston-based XenoTherapeutics, which designed the safety protocols for the special live-pig tissue graft.

Paul Holzer, CEO of XenoTherapeutics said, We have taken a small but unprecedented step in bringing xenotransplantation from theory to therapy, one that we hope will advance this promising field of medicine and benefit patients around the world.

Human skin grafts are subject to a national shortage and can be expensive, therefore using the pig skin can serve as a viable alternative, according to MGH.

But Alka Chandna, vice president of laboratory investigations cases at PETA, said, Its categorically unethical to steal organs from another sentient being whos still using them. Pigs are individuals, not warehouses for spare parts, said Chandna.

Chandna said, Tinkering with the genes of these intelligent, sensitive beings to turn them into organ factories is a waste of lives, time and money and the suffering caused is unimaginable.

The advancement of the procedure reaches back decades to genetically modified pigs that were developed in the 1990s at MGH by Dr. David Sachs.

The modifications removed a gene specific to pigs and not present in humans, allowing the pig skin to appear less foreign to the human immune system.

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MGH doctors perform first-ever live-cell pig skin graft to burn patient - Boston Herald

While many people love colorful photos of landscapes, flowers or rainbows, some biomedical researchers treasure vivid images on a much smaller scale as tiny as one-thousandth the width of a human hair.

To study the micro world and help advance medical knowledge and treatments, these scientists use fluorescent nano-sized particles.

Quantum dots are one type of nanoparticle, more commonly known for their use in TV screens. Theyre super tiny crystals that can transport electrons. When UV light hits these semiconducting particles, they can emit light of various colors.

That fluorescence allows scientists to use them to study hidden or otherwise cryptic parts of cells, organs and other structures.

Im part of a group of nanotechnology and neuroscience researchers at the University of Washington investigating how quantum dots behave in the brain.

Common brain diseases are estimated to cost the U.S. nearly US$800 billion annually. These diseases including Alzheimers disease and neurodevelopmental disorders are hard to diagnose or treat.

Nanoscale tools, such as quantum dots, that can capture the nuance in complicated cell activities hold promise as brain-imaging tools or drug delivery carriers for the brain. But because there are many reasons to be concerned about their use in medicine, mainly related to health and safety, its important to figure out more about how they work in biological systems.

Researchers first discovered quantum dots in the 1980s. These tiny particles are different from other crystals in that they can produce different colors depending on their size. They are so small that that they are sometimes called zero-dimensional or artificial atoms.

The most commonly known use of quantum dots nowadays may be TV screens. Samsung launched their QLED TVs in 2015, and a few other companies followed not long after. But scientists have been eyeing quantum dots for almost a decade. Because of their unique optical properties they can produce thousands of bright, sharp fluorescent colors scientists started using them as optical sensors or imaging probes, particularly in medical research.

Scientists have long used various dyes to tag cells, organs and other tissues to view the inner workings of the body, whether that be for diagnosis or for fundamental research.

The most common dyes have some significant problems. For one, their color often cannot survive very long in cells or tissues. They may fade in a matter of seconds or minutes. For some types of research, such as tracking cell behaviors or delivering drugs in the body, these organic dyes simply do not last long enough.

Quantum dots would solve those problems. They are very bright and fade very slowly. Their color can still stand out after a month. Moreover, they are too small to physically affect the movement of cells or molecules.

Those properties make quantum dots popular in medical research. Nowadays quantum dots are mainly used for high resolution 3D imaging of cells or molecules, or real-time tracking probes inside or outside of animal bodies that can last for an extended period.

But their use is still restricted to animal research, because scientists are concerned about their use in human beings. Quantum dots commonly contain cadmium, a heavy metal that is highly poisonous and carcinogenic. They may leak the toxic metal or form an unstable aggregate, causing cell death and inflammation. Some organs may tolerate a small amount of this, but the brain cannot withstand such injury.

My colleagues and I believe an important first step toward wider use of quantum dots in medicine is understanding how they behave in biological environments. That could help scientists design quantum dots suitable for medical research and diagnostics: When theyre injected into the body, they need to stay small particles, be not very toxic and able to target specific types of cells.

We looked at the stability, toxicity and cellular interactions of quantum dots in the developing brains of rats. We wrapped the tiny quantum dots in different chemical coats. Scientists believe these coats, with their various chemical properties, control the way quantum dots interact with the biological environment that surrounds them. Then we evaluated how quantum dots performed in three commonly used brain-related models: cell cultures, rat brain slices and individual live rats.

We found that different chemical coats give quantum dots different behaviors. Quantum dots with a polymer coat of polyethylene glycol (PEG) were the most promising. They are more stable and less toxic in the rat brain, and at a certain dose dont kill cells. It turns out that PEG-coated quantum dots activate a biological pathway that ramps up the production of a molecule that detoxifies metal. Its a protective mechanism embedded in the cells that happens to ward off injury by quantum dots.

Quantum dots are also eaten by microglia, the brains inner immune cells. These cells regulate inflammation in the brain and are involved in multiple brain disorders. Quantum dots are then transported to the microglias lysosomes, the cells garbage cans, for degradation.

But we also discovered that the behaviors of quantum dots vary slightly between cell cultures, brain slices and living animals. The simplified models may demonstrate how a part of the brain responds, but they are not a substitute for the entire organ.

For example, cell cultures contain brain cells but lack the connected cellular networks that tissues have. Brain slices have more structure than cell cultures, but they also lack the full organs blood-brain barrier its Great Wall that prevents foreign objects from entering.

Our results offer a warning: Nanomedicine research in the brain makes no sense without carefully considering the organs complexity.

That said, we think our findings can help researchers design quantum dots that are more suitable for use in living brains. For example, our research shows that PEG-coated quantum dots remain stable and relatively nontoxic in living brain tissue while having great imaging performance. We imagine they could be used to track real-time movements of viruses or cells in the brain.

In the future, along with MRI or CT scans, quantum dots may become vital imaging tools. They might also be used as traceable carriers that deliver drugs to specific cells. Ultimately, though, for quantum dots to realize their biomedical potential beyond research, scientists must address health and safety concerns.

Although theres a long way to go, my colleagues and I hope the future for quantum dots may be as bright and colorful as the artificial atoms themselves.

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Quantum dots that light up TVs could be used for brain research - The Conversation US