first_imgEvery person has a different repertoire of the trillions of T cell receptors, known as TCRs. But at least some of those TCRs are identical to those in other people. “We call those public T cell receptor sequences, because, theoretically, many people across the population will elicit those responses,” Dr. Baldo said.When the pandemic started, Adaptive Technologies had already been working with Microsoft to design a TCR-based diagnostic test for Lyme disease, a project made possible by the advent of fast and inexpensive sequencing technologies.Pivoting to the coronavirus, the team identified 135,000 public TCRs that recognize 545 fragments of the virus. About 11 of these 545 antigens elicit the largest immune response, the researchers reported in September. (Only one of these antigens, the spike protein, is being used to develop vaccines.)In the new work, the team analyzed samples from 2,200 people in Vo, Italy, which tested all 2,900 of its residents for presence of the coronavirus in March, when cases were soaring there. Their test, called the T-Detect, correctly identified 97 percent of those who had a confirmed diagnosis, compared with 77 percent from a commercial antibody test called DiaSorin. The results are freely available in a database called ImmuneCode.The company is creating a point-of-care test for the general public that can diagnose prior infection, as well as a sophisticated version for vaccine companies interested in tracking T cell responses to their candidates. Each of the trillions of T cells present at birth carries a unique receptor on its surface that can spot a different molecule, or antigen, from potential invaders. This enormous diversity among T-cell receptors enables the human body to recognize virtually any new pathogen that it may encounter (although a vast majority may never meet their match.) But it also makes it painfully onerous for scientists to identify the 20 or 30 T cells among the trillions that can recognize fragments of a specific pathogen like the coronavirus.“One of the brutal things about immunology is that all white blood cells look the same,” said Shane Crotty, a virologist at the La Jolla Institute for Immunology. “You can’t even tell B cells from T cells, let alone T cells specific to a virus.” To find the T cells specific to a virus, researchers must first separate the bulk of immune cells from a few milliliters of blood, which takes time. Then they wash and count the cells, and stimulate them with pieces of the virus to identify the tiny pool of T cells that respond. The cells that are activated release a molecule called gamma interferon that serves as a signal of their activity.“The better the assay, the more complicated it is,” Dr. Crotty said. “You get more and more information, but it becomes more and more complicated.”A single researcher can process no more than five blood samples over the course of a day and a half.“That’s pretty much why every single paper that is done on T cells, the number of subjects that are studied is never higher than 100,” said Dr. Antonio Bertoletti, a virologist at Duke NUS Medical School in Singapore. “There has also never been great demand for wading into the intricacies of T cell tests.” The Coronavirus Outbreak ›Words to Know About TestingConfused by the terms about coronavirus testing? Let us help: – Advertisement – Experts not involved in the work praised the company’s innovative approach but said that they wanted to see evidence that the test was specific to the coronavirus.“There isn’t a consensus out there now that you can take TCRs from one person that are specific for a given person and tell that another person is infected with the virus in a consistent way,” Dr. Crotty said. “If they’ve figured out a way to do that that’s awesome, but it’s pretty novel.”A commercial test also would not offer people information beyond evidence of past infection, cautioned Akiko Iwasaki, an immunologist at Yale University. But if the test is specific to the new coronavirus, she said, “it will give us a much more sensitive way of measuring whether a person has been exposed.”The test may also offer insights into Covid-19. And about 5 percent of patients who are severely ill show a “tremendous drop” in their T cell response, Dr. Baldo said. But in a vast majority of people, the T cell response seems to peak around Day 10 and persists for many months, he said, adding: “We’re seeing an earlier, a more robust and even a more durable T cell response as opposed to the antibody response.” “What we’re developing is essentially a way to look at that cellular part of immunity,” said Dr. Lance Baldo, chief medical officer of Adaptive Biotechnologies.Antibodies have so far hogged much of the attention — mostly because testing for them is quick and easy. But levels of antibodies tend to wane after the active illness is resolved and may be undetectable within a few months.Several studies have suggested that T cells that remember the virus persist for at least six months. “There’s a growing realization that T cells are important and may even be a better indicator of clinical outcome” than antibodies, said Alessandro Sette, an immunologist at the La Jolla Institute for Immunology in California.- Advertisement – But isolating T cells is an elaborate and onerous process, which has severely limited information about their role.center_img A new type of test can detect a person’s immune response to the coronavirus better than a widely used antibody test, according to research released on Tuesday.The test, if authorized by the Food and Drug Administration, would be the first commercial product to detect the response of a T cell — a type of immune cell — to the virus. Antibodies have dominated the conversation on immunity since the start of the pandemic, but scientists believe that T cells may be just as important in preventing reinfection.- Advertisement – Adaptive Biotechnologies has a completely different approach: Instead of looking at the cells, the company focused on sequencing the proteins on the cells’ surface. Exposure to a pathogen rouses multiple arms of the immune system: antibodies, but also immune cells that can marshal the fight against the intruder.- Advertisement – The test was developed by Adaptive Biotechnologies, a company based in Seattle. The company used small blood samples from 1,000 people across 25 metropolitan areas in the United States as well as another 3,500 participants from Europe to create the test, which can detect a recent or past infection of the coronavirus.The company’s data has not yet been reviewed for publication in a scientific journal, but experts say the work is promising for assessing T cells’ role in the illness caused by the coronavirus. Antibody: A protein produced by the immune system that can recognize and attach precisely to specific kinds of viruses, bacteria, or other invaders.Antibody test/serology test: A test that detects antibodies specific to the coronavirus. Antibodies begin to appear in the blood about a week after the coronavirus has infected the body. Because antibodies take so long to develop, an antibody test can’t reliably diagnose an ongoing infection. But it can identify people who have been exposed to the coronavirus in the past.Antigen test: This test detects bits of coronavirus proteins called antigens. Antigen tests are fast, taking as little as five minutes, but are less accurate than tests that detect genetic material from the virus.Coronavirus: Any virus that belongs to the Orthocoronavirinae family of viruses. The coronavirus that causes Covid-19 is known as SARS-CoV-2. Covid-19: The disease caused by the new coronavirus. The name is short for coronavirus disease 2019.Isolation and quarantine: Isolation is the separation of people who know they are sick with a contagious disease from those who are not sick. Quarantine refers to restricting the movement of people who have been exposed to a virus.Nasopharyngeal swab: A long, flexible stick, tipped with a soft swab, that is inserted deep into the nose to get samples from the space where the nasal cavity meets the throat. Samples for coronavirus tests can also be collected with swabs that do not go as deep into the nose — sometimes called nasal swabs — or oral or throat swabs.Polymerase Chain Reaction (PCR): Scientists use PCR to make millions of copies of genetic material in a sample. Tests that use PCR enable researchers to detect the coronavirus even when it is scarce.Viral load: The amount of virus in a person’s body. In people infected by the coronavirus, the viral load may peak before they start to show symptoms, if symptoms appear at all.last_img read more

first_img But Peter Crouch levelled three minutes before half-time, and five minutes after the break Stephen Ireland put the hosts ahead. Schurrle quickly equalised with another fine finish and it looked like both sides would have to settle for a point until Assaidi’s brilliant intervention earned victory. Stoke’s last win over Chelsea came in the League Cup in 1995 when Potters manager Mark Hughes was in the Blues side, while their most recent league victory was in 1975. The result ended Chelsea’s three-match winning run and saw them drop below Liverpool into third, while leaders Arsenal now have the chance to open up a seven-point gap on Sunday. Schurrle was one of two changes to the Chelsea side from Wednesday’s win over Sunderland and he was soon into the action, pulling the ball back for Ramires, who shot well over the bar from 10 yards out. The Brazilian should have done much better, but the visitors only had to wait until the 10th minute to take the lead. This time Schurrle did it all himself, picking the ball up in midfield, holding off Ryan Shawcross and Glenn Whelan before shooting across Asmir Begovic and into the bottom corner. It was Schurrle’s second Premier League goal, and Chelsea had plenty of chances to add to their lead. Juan Mata shot straight at Begovic in the 16th minute after a free-kick fell to him on the edge of the box, while the Spain international then failed to pick out Fernando Torres in the centre after Jonathan Walters had given the ball away. Ramires was the man most culpable, the midfielder having three further efforts during the first half but failing to really test Begovic. Stoke had been forced into a change in the 18th minute when Charlie Adam, their main creative force, limped off and was replaced by Ireland. The Potters were showing some decent play in midfield but their final ball was lacking and front man Crouch was isolated. They had their first chance in the 38th minute when Steven N’Zonzi found Marko Arnautovic on the left and his cross picked out Walters at the back post, but the Republic of Ireland man, who last season scored two own goals and missed a penalty in the same fixture, could only nod wide. The equaliser came from a break instigated by Geoff Cameron, who found Walters down the right. His cross was just out of the reach of a diving Ireland but Arnautovic won a corner and his delivery was turned in by Crouch. Chelsea had only themselves to blame, with Mikel leaving Crouch unmarked and Petr Cech opting to come off his line but getting nowhere near the ball. Stoke carried the momentum into the second half and stunned Chelsea by taking the lead in the 50th minute. Walters broke down the right and squared the ball for Ireland, who took one touch to control before curling a precision shot in off the far post. The Britannia roared its approval but Stoke were ahead for just three minutes, and it was Schurrle again. A Mata free-kick was half cleared by Crouch to the German on the edge of the box, who once again produced a clinical finish into the far corner. Schurrle almost completed his hat-trick in the 57th minute but although he beat Begovic again his curling shot bounced off the bar. Both teams were committing men forward, and 10 minutes later it was Stoke’s turn to go close. N’Zonzi crossed for Crouch, who set up Ireland in space eight yards out but this time he could only curl his shot high and wide. Schurrle’s hat-trick hopes were ended as Mourinho sent on Frank Lampard and Samuel Eto’o, and the latter swiftly had a sight of goal but poked his shot just wide. Marc Muniesa gave away a free-kick on the edge of the box for a foul on Demba Ba, but Begovic was safely behind Lampard’s shot, which found its way through a 10-man wall. Walters was booked for shoving John Terry in the chest and was swiftly replaced by Assaidi and his strike handed Mourinho his first ever Premier League defeat in December. Oussama Assaidi stunned Chelsea with a superb 90th-minute winner as Stoke won 3-2 to claim their first league victory over the Blues in 38 years. Press Association The on-loan Liverpool winger came on as a substitute six minutes from time and his first real contribution was to pick the ball up on the left, cut inside and unleash a ferocious shot into the top corner. Jose Mourinho’s first trip to the Britannia Stadium began well as Andre Schurrle gave Chelsea a 10th-minute lead. last_img read more

first_imgA successful Bosnian alpinist, 29-year-old Armin Gazic, was killed in an accident that happened downstream from the Buna Canals in the Neretva River today, it has been confirmed for Klix.ba. In the last few months, Gazic has been in love with kayaking in addition to mountaineering, and he often drove from Jablanica to Mostar, and today’s event ended tragically.Namely, as Klix.ba finds out, Armin and two colleagues planned to go downstream, but at one point there was an accident. Two people who were with Armin managed to reach the shore, and his body was found a few hours later.Armin Gazic was an experienced alpinist, and in his career so far, he has reached peaks up to 5,600 meters, as is Mount Elbrus in Russia. He was practicing mountaineering for 19 years, and four years ago he acquired the title of mountaineering instructor. In the team with Haris Kalajdzisalihovic, he became the first alpinist from Bosnia and Herzegovina to climb the northern rock of the Matterhorn. Mr. Gazic was also a three-time national champion in sport climbing, and the winner of the recognition of the Sports Federation of BiH for his contribution and development of the sport.Mr. Gazic, was seriously injured on February 28thin 2014, falling from a height of 50 meters from mountain Prenj near Konjic, and he has started  a “new life” in 2015.last_img read more