12/4/2023 0 Comments Spike protein heartMoreover, cleaved Spike (S) protein molecules could be released into the bloodstream from the leaking pulmonary epithelial-endothelial barrier in patients with severe COVID-19, opening to the possibility of non-infective diseases in organs distant from the primary site of infection. To date, the mechanism by which the virus infects and disrupts the heart vascular cells was not identified yet. Emerging reports indicate CD147/Basigin (BSG), highly expressed in endothelial cells (EC), is an alternative SARS-CoV-2 receptor. The multifunctional spike protein being the key determinant in these phenomena.Background: Human cardiac pericytes (PC) were proposed as the main cellular target for SARS-CoV-2 in the heart due to high transcriptional levels of the angiotensin-converting enzyme 2 (ACE2) receptor. If confirmed, this may indicate a dissociation between infectivity and capacity of SARS-CoV-2 to cause cardiac cell damage. "However, in the case of the current Omicron wave, experts say there haven't been any cardiac symptoms reported so far although it is still very early to say for sure. "The Omicron variant has multiple mutations to its spike protein, which helps the virus to enter and infect human cells, resulting in higher transmissibility and stronger binding with human cells." In addition, cleaved spike protein particles could amplify the damage induced by the engagement of the full virion with vascular cells." "Our findings newly suggest that SARS-CoV-2 can damage vascular cells without infecting them. Furthermore, people with pre-existing cardiovascular diseases are more likely to die of COVID-19." Professor Paolo Madeddu, cardiologist and the study lead from the University's Bristol Medical School, added that "microvascular complications are frequent and harmful in patients with COVID-19, with up to 11 percent of those hospitalized in intensive care units having myocardial damage or having suffered a heart attack. Hopefully, CD147 blocking antibodies could represent a new treatment to alleviate cardiovascular complications in COVID-19 patients." This new study shows that the spike protein jeopardizes this interaction and transforms pericytes into inflammatory cells. Our ongoing research on human cardiac pericytes indicates these cells co-operate with coronary endothelial cells during healing from a heart attack. Elisa Avolio, the study's first author from the University's Bristol Medical School, said that "pericytes are essential cells of the heart, although their role in maintaining the structural integrity of the coronary vascular tree has emerged only recently. Interestingly, the team found that antibodies blocking CD147-a receptor for the spike protein-protected heart pericytes from damage.įinally, the team identified the presence of the SARS-CoV-2 spike protein in blood samples obtained from COVID-19 patients, which opens the possibility that spike protein particles traveling through the circulation can reach a site distant from the respiratory system and cause systemic damage.ĭr. The spike protein made pericytes unable to interact with their companion endothelial cells and induced them to secrete inflammatory cytokines, suggesting the spike protein is harmful to human cardiac cells. Intrigued by this finding, in a second test-tube experiment, the researchers challenged the cardiac pericytes with the spike protein alone, without the virus. Surprisingly, they found the heart pericytes were not infected. The team also sought to investigate whether heart cells contribute to producing excess cytokines.Ī research team led by Bristol's Professor Paolo Madeddu exposed human heart pericytes, which are cells that wrap small blood vessels in the heart, to SARS-CoV-2 Alpha and Delta variants, along with the original Wuhan virus. This response, also known as 'the cytokine storm', comes from our immune cells, whereby cytotoxic cells attack and kill the infected cells by releasing proteins, called cytokines. Until now, it remained unclear whether heart cells are infected by the virus or damaged because of an excess cytotoxic defense response. In this new study, a multidisciplinary research team from the University's Bristol Heart Institute sought to investigate how SARS-CoV-2 interacts with heart cells causing the myocardial damage seen in COVID-19 patients.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |