The press service of the Medical College of Mount Sinai Hospital in the United States for the first time reported the cultivation of bat stem cells that can infect SARS-CoV-2 and are carriers of Covid-19 isotopes.
According to the School of Medicine, experiments with these cell cultures have revealed unique mechanisms that help bats coexist with viruses.
Professor Adolfo Garcia-Sastre said: “Comparison of these stem cells with similar organs of other mammals revealed the unique features of their life. The most unusual feature is the presence inside these cells of large vesicles filled with various viruses, including coronaviruses. … and these viruses in a way that does not prevent bat cells from growing and reproducing, which may indicate a symbiotic nature of their interactions.”
Most scientists still believe that the primary source of the SARS-CoV-2 virus and the causative agent of “Covid-19” are bats that live in the forests of Southeast Asia.
This idea aroused great interest in the study of viruses of bat groups and the nature of the interaction of their immune system with various infectious agents.
Prof. Garcia-Sastre and his colleagues have taken a big step towards obtaining such information in experiments with reprogrammed stem cells of “great horseshoe bats” and “great mouse eared bats”, each of these and other bats carrying a large number of viruses, including including many types of coronaviruses.
A unique feature of bat cells
Scientists have long wondered how these animals can carry viral infections without showing obvious symptoms. To answer this question, biologists took several samples of bats and large horseshoe bats, extracted connective tissue cells from their bodies, and tried to “reprogram” them using a standard procedure. used in stem cell transplantation in humans and mice.
To the researchers’ surprise, this procedure unexpectedly didn’t work, forcing them to select a group of signaling molecules unique to bats needed to trigger the stem cell growth process.
Having solved this problem, biologists have prepared cultures of stem cells of “great horseshoe bats” and “great eared mouse bats” and studied their biological activity in detail.
These experiments showed the presence in the stem cells of both bats of large isolated vesicles containing many viable particles of retroviruses, as well as parts of their genomes.
Among these fragments, the researchers found that the nucleotide sequences are very similar in structure to the genome of the RaTG13 coronavirus, a putative relative of SARS-CoV-2.
The presence of these “viral vesicles” did not prevent stem cells from actively growing and multiplying.
According to the researchers, this is likely due to increased activity of the Col3a1 and Muc1 genes, as well as six other DNA regions.
Professor Garcia-Sastre and his colleagues concluded that further study of these genes will help biologists unravel the molecular mechanisms underlying the coexistence of viruses and bats.