‘Drug Factory’ Implants Could Eliminate Specific Lung Cancer

Rice University and Baylor College of Medicine researchers have shown they can seradicate advanced-stage mesothelioma tumor in mice in just a few days with a treatment combining Rice’s cytokinedrug factoryimplants and a checkpoint inhibitor drug.

The researchers administered the drug-producing beads, which are no larger than the head of a pin, next to tumors where they could produce continuous, high doses of interleukin-2 (IL-2), a natural compound that activates white blood cells to fight cancer. The study, published online today in Clinical Cancer Research, is the latest in a string of successes for the drug-factory technology invented in the lab of Rice bioengineer Omid Veiseh, including Food and Drug Administration (FDAapproval to begin clinical trials of the technology this fall in ovarian cancer patients.

From the beginning, our objective was to develop a platform therapy that can be used for multiple different types of immune system disorders or different types of cancers,” said Rice graduate student Amanda Nash, who spent several years developing the implant technology with study co-lead author Samira Aghlara-Fotovat, a fellow student in Veiseh’s lab.

The cytokine factories consist of alginate beads loaded with tens of thousands of cells that are genetically engineered to produce natural IL-2, one of two cytokines the FDA has approved for treatment of cancer. The factories are just 1.5 millimeters wide and can be implanted with minimally invasive surgery to deliver high doses of IL-2 directly to tumors. In the mesothelioma study, the beads were placed beside tumors and inside the thin layer of tissue known as the pleura, which covers the lungs and lines the interior wall of the chest.

I take care of patients who have malignant pleural mesothelioma,” said Dr. Bryan Burt, professor and chief of Baylor’s Division of Thoracic Surgery in the Michael E. DeBakey Department of Surgery. “This is a very aggressive malignancy of the lining of the lungs. And it’s very hard to treat completely by surgical resection. In other words, there is often residual disease that is left behind. The treatment of this residual disease with local immunotherapy — the local delivery of relatively high doses of immunotherapy to that pleural space — is a very attractive way to treat this disease.”

Veiseh said the mesothelioma study began when Burt and Baylor surgeon and associate professor Dr. Ravi Ghanta heard about the early results of ovarian cancer animal tests Veiseh’s team was conducting with collaborators at the University of Texas MD Anderson Cancer Center. In March, Veiseh and MD Anderson collaborators published a study showing IL-2-producing beads could eradicate advanced-stage ovarian and colorectal tumors in mice in less than a week.

They were really impressed by the preclinical data we had in ovarian cancer,” Veiseh said of Burt and Ghanta. “And they asked the question, ‘Could we actually leverage the same system for mesothelioma?’

Source: https://blogs.bcm.edu/

New Bandage Could Seal Hole in the Heart

A Band-Aid® adhesive bandage is an effective treatment for stopping external bleeding from skin wounds, but an equally viable option for internal bleeding does not yet exist. Surgical glues are often used inside the body instead of traditional wound closure techniques like stitches, staples, and clips because they reduce the patient’s time in the hospital and lower the risk of secondary injury/damage at the wound site. An effective surgical glue needs to be strong, flexible, non-toxic, and able to accommodate movement, yet there are no adhesives currently available that have all of those properties. Researchers at the Wyss Institute (Harvard University) have developed a new super-strong hydrogel adhesive inspired by the glue secreted by a common slug that is biocompatible, flexible, and can stick to dynamically moving tissues even in the presence of blood.

The hydrogel itself is a hybrid of two different types of polymers: a seaweed extract called alginate that is used to thicken food, and polyacrylamide, which is the main material in soft contact lenses. When these relatively weak polymers become entangled with each other, they create a molecular network that demonstrates unprecedented toughness and resilience for hydrogel materials – on par with the body’s natural cartilage. When combined with an adhesive layer containing positively-charged polymer molecules (chitosan), the resulting hybrid material is able to bind to tissues stronger than any other available adhesive, stretch up to 20 times its initial length, and attach to wet tissue surfaces undergoing dynamic movement (e.g., a beating heart).

Studies of the hydrogel adhesive demonstrated that it is capable of withstanding three times the amount of tension that disrupts the best current medical adhesives, maintaining its stability and adhesion when implanted into rats for two weeks, and sealing a hole in a pig heart that was subjected to tens of thousands of cycles of pumping. Additionally, it caused no tissue damage or adhesions to surrounding tissues when applied to a liver hemorrhage in mice.

The hydrogel adhesive has numerous potential applications in the medical field, either as a patch that can be cut to desired sizes and applied to many tissues including bone, cartilage, tendon, or pleura, or as an injectable solution for deeper injuries. It can also be used to attach medical devices to their target structures, such as an actuator to support heart function. While the current iteration is designed to be a permanent structure, it could be made to biodegrade over time as the body heals from injury.

Source: https://wyss.harvard.edu/

Injectable Electroactive “Microbots” Heal Broken Bones

Inspired by the growth of bones in the skeleton, researchers at the universities of Linköping in Sweden and Okayama in Japan have developed a combination of materials that can morph into various shapes before hardening. The material is initially soft, but later hardens through a bone development process that uses the same materials found in the skeleton…

When we are born, we have gaps in our skulls that are covered by pieces of soft connective tissue called fontanelles. It is thanks to fontanelles that our skulls can be deformed during birth and pass successfully through the birth canal. Post-birth, the fontanelle tissue gradually changes to hard bone. Now, researchers have combined materials which together resemble this natural process.

We want to use this for applications where materials need to have different properties at different points in time. Firstly, the material is soft and flexible, and it is then locked into place when it hardens. This material could be used in, for example, complicated bone fractures. It could also be used in microrobots – these soft microrobots could be injected into the body through a thin syringe, and then they would unfold and develop their own rigid bones”, says Edwin Jager, associate professor at the Department of Physics, Chemistry and Biology (IFM) at Linköping University.

The idea was hatched during a research visit in Japan when materials scientist Edwin Jager met Hiroshi Kamioka and Emilio Hara, who conduct research into bones. The Japanese researchers had discovered a kind of biomolecule that could stimulate bone growth under a short period of time. Would it be possible to combine this biomolecule with Jager’s materials research, to develop new materials with variable stiffness?

In the study published in Advanced Materials, the researchers constructed a kind of simple “microrobot”, one which can assume different shapes and change stiffness. The researchers began with a gel material called alginate. On one side of the gel, a polymer material is grown. This material is electroactive, and it changes its volume when a low voltage is applied, causing the microrobot to bend in a specified direction. On the other side of the gel, the researchers attached biomolecules that allow the soft gel material to harden. These biomolecules are extracted from the cell membrane of a kind of cell that is important for bone development. When the material is immersed in a cell culture medium – an environment that resembles the body and contains calcium and phosphor – the biomolecules make the gel mineralise and harden like bone.

One potential application of interest to the researchers is bone healing. The idea is that the soft material, powered by the electroactive polymer, will be able to manoeuvre itself into spaces in complicated bone fractures and expand. When the material has then hardened, it can form the foundation for the construction of new bone. In their study, the researchers demonstrate that the material can wrap itself around chicken bones, and the artificial bone that subsequently develops grows together with the chicken bone.

Source: https://liu.se/