Showing posts with label immunity. Show all posts
Showing posts with label immunity. Show all posts

Saturday, 25 April 2020

CHINESE COVID-19 VACCINE EFFECTIVE IN MONKEYS

https://drive.google.com/uc?export=view&id=16enXXX0h13Od9b_Ved_l_KJ363pvNYmgResearchers at Beijing pharmaceutical company Sinovac Biotech have developed an experimental COVID-19 vaccine that it says protected macaques from infection, ScienceMagazine reports.

The vaccine was based on a tried-and-true formulation that included an inactivated version of the virus SARS-CoV-2, as detailed in a preprint uploaded to the server bioRxiv on April 19.

“These data support the rapid clinical development of SARS-CoV-2 vaccines for humans,” reads the paper.

The team at Sinovac injected eight macaque monkeys with two different doses. Three weeks after injection, they introduced the coronavirus straight into the money’s lungs. There were reportedly no side effects.

None of the monkeys developed an infection beyond a small “viral blip.” A less fortunate control group of monkeys developed severe pneumonia after being infected by the virus.

“This is old school but it might work,” Florian Krammer, a virologist at the Icahn School of Medicine at Mount Sinai, who co-authored a status report on COVID vaccine candidates, told Science Mag. “What I like most is that many vaccine producers, also in lower–middle-income countries, could make such a vaccine.”

Critics say, though, that the sample size in Sinovac’s trial was too small to produce generalizable results. Questions also remain about the viability of the vaccine candidate for use in humans — especially considering that monkeys don’t experience the same severe symptoms of COVID as humans.

In a separate Sinovac experiment, the researchers mixed a cocktail of antibodies from patients in China, Italy, Switzerland, Spain, and the United Kingdom with the virus.

According to the team, the antibodies “potently neutralized 10 representative SARS-CoV-2 strains, indicative of a possible broader neutralizing ability.”

And that’d be good news.

“This provides strong evidence that the virus is not mutating in a way that would make it resistant to a #COVID19 vaccine,” tweeted of Oregon Health & Science University immunologist Mark Slifka on Wednesday.

Sinovac Biotech is now planning trials on thousands of human subjects.

Wednesday, 22 January 2020

SCIENTISTS DISCOVER IMMUNE CELL THAT KILLS MOST CANCERS

A newly discovered immune cell could lead to the creation of a universal oncology treatment — a system that would work for all cancers, in all people.https://drive.google.com/uc?export=view&id=1i1bAOOH3r8oVOqKKXVae4xWI-PTr13Wo

The treatment leverages T-cells, a type of white blood cell that helps our bodies’ immune systems by scanning for and killing abnormal cells. For background, scientists have recently started harnessing that ability in the fight against cancer through CAR-T, which involves removing T-cells from a patient’s blood and genetically engineering them to seek out and destroy cancer cells.

While promising, CAR-T has limitations. It’s patient-specific, works against only a small number of cancers, and isn’t effective against solid tumors, which comprise the majority of cancers.

On Monday, researchers from Cardiff University published a new study in the journal Nature Immunology detailing their discovery of a T-Cell equipped with a new type of T-cell receptor (TCR) that recognizes a molecule called MR1.

This molecule appears on the surface of many types of cancer cells as well as healthy cells, but T-cells equipped with this TCR know to kill only cancer cells.

And not just the kind linked to a single type of cancer, either. When the Cardiff researchers equipped T-cells in lab tests with this new TCR, the cells killed lung, skin, blood, colon, breast, bone, prostate, ovarian, kidney and cervical cancer cells — all while ignoring healthy cells.

In another lab test, the team modified the T-cells of melanoma patients to express the newly discovered TCR and found that the cells could then target and destroy both that patient’s own cancer cells and the cancer cells of other patients.

The team has yet to test the modified T-cells in actual cancer patients, but when tested in mice injected with human cancers, the cells recognized the MR1 molecule and exhibited “encouraging” cancer-killing abilities, according to a Cardiff press release.

The Cardiff scientists now plan to conduct additional tests. If those goes as hoped, the treatment could be ready for patients within a few years, researcher Andrew Sewell said in the press release.

“Cancer-targeting via MR1-restricted T-cells is an exciting new frontier,” he added. “It raises the prospect of a ‘one-size-fits-all’ cancer treatment; a single type of T-cell that could be capable of destroying many different types of cancers across the population. Previously nobody believed this could be possible.”