The News of Us
  • Home
  • Business
  • Politics
  • Science and Technology
  • Health
  • Subscribe Us
No Result
View All Result
The News of Us
  • Home
  • Business
  • Politics
  • Science and Technology
  • Health
  • Subscribe Us
No Result
View All Result
The News of Us
No Result
View All Result

Human Lung and Brain Organoids Respond Differently to SARS-CoV-2 Infection in Lab Tests

admin by admin
February 28, 2021
in Science and Technology

COVID-19, the disease caused by the pandemic coronavirus SARS-CoV-2, is primarily regarded as a respiratory infection. Yet the virus has also become known for affecting other parts of the body in ways not as well understood, sometimes with longer-term consequences, such as heart arrhythmia, fatigue and “brain fog.”

Researchers at University of California San Diego School of Medicine are using stem cell-derived organoids — small balls of human cells that look and act like mini-organs in a laboratory dish — to study how the virus interacts with various organ systems and to develop therapies to block infection.

“We’re finding that SARS-CoV-2 doesn’t infect the entire body in the same way,” said Tariq Rana, PhD, professor and chief of the Division of Genetics in the Department of Pediatrics at UC San Diego School of Medicine and Moores Cancer Center. “In different cell types, the virus triggers the expression of different genes, and we see different outcomes.”

Rana’s team published their findings in Stem Cell Reports.

Like many organs, the team’s lung and brain organoids produce the molecules ACE2 and TMPRSS2, which sit like doorknobs on the outer surfaces of cells. SARS-CoV-2 grabs these doorknobs with its spike protein as a means to enter cells and establish infection.

Rana and team developed a pseudovirus — a noninfectious version of SARS-CoV-2 — and labeled it with green fluorescent protein, or GFP, a bright molecule derived from jellyfish that helps researchers visualize the inner workings of cells. The fluorescent label allowed them to quantify the binding of the virus’ spike protein to ACE2 receptors in human lung and brain organoids, and evaluate the cells’ responses.

The team was surprised to see approximately 10-fold more ACE2 and TMPRSS2 receptors and correspondingly much higher viral infection in lung organoids, as compared to brain organoids. Treatment with viral spike protein or TMPRSS2 inhibitors reduced infection levels in both organoids.

“We saw dots of fluorescence in the brain organoids, but it was the lung organoids that really lit up,” Rana said.

Besides differences in infectivity levels, the lung and brain organoids also differed in their responses to the virus. SARS-CoV-2-infected lung organoids pumped out molecules intended to summon help from the immune system — interferons, cytokines and chemokines. Infected brain organoids, on the other hand, upped their production of other molecules, such as TLR3, a member of the toll-like receptor family that plays a fundamental role in pathogen recognition and activation of innate immunity.

Rana explained that, while it might seem at first like the brain organoid reaction is just another form of immune response, those molecules can also aid in programmed cell death. Rana’s team previously saw a similar brain cell response to Zika virus, an infection known to stunt neonatal brain development.

“The way we are seeing brain cells react to the virus may help explain some of the neurological effects reported by patients with COVID-19,” Rana said.

Of course, organoids aren’t exact replicas of human organs. They lack blood vessels and immune cells, for example. But they provide an important tool for studying diseases and testing potential therapies. According to Rana, organoids mimic the real-world human condition more accurately than cell lines or animal models that have been engineered to over-express human ACE2 and TMPRSS2.

“In animals over-expressing ACE2 receptors, you see everything light up with infection, even the brain, so everyone thinks this is the real situation,” Rana said. “But we found that’s likely not the case.”

In addition to their work with the pseudovirus, the team validated their findings by applying live, infectious SARS-CoV-2 to lung and brain organoids in a Biosafety Level-3 laboratory — a facility specially designed and certified to safely study high-risk microbes.

Source: UC San Diego

[Read More…]

Previous Post

Comet Makes a Pit Stop Near Jupiter’s Asteroids

Next Post

Nuclear physicists on the hunt for squeezed protons

Related Posts

Science and Technology

Bubble with titanium triggers titanic explosions

Science and Technology

Black hole is closest to Earth, among the smallest ever discovered

Science and Technology

Tesla drives on Autopilot through a regulatory grey zone

Science and Technology

Does Big Tech Hurt U.S. National Security?

Science and Technology

Data Is Power

Science and Technology

Hubble watches cosmic light bend

Next Post

Nuclear physicists on the hunt for squeezed protons

Follow us for latest Business News | Political News | Science & Technology News | Health News.

Subscribe Us

By clicking subscribe, I authorize: (1) The News Of Us to use and share my information in accordance with its Terms of Service and Privacy Policy, and (2) The News Of Us or third-party companies, including The News Of Us’s business partners, to contact me by email with offers for goods and services at the email address provided. Please note that the information you have provided to us may be supplemented with additional information obtained from other sources.

© 2021 The News of Us, - All Rights Reserved.

  • Subscribe Us
  • Contact Us
  • Unsubscribe
  • Privacy Policy
No Result
View All Result
  • Home
  • Business
  • Politics
  • Science and Technology
  • Health
  • Subscribe Us

© 2021 The News of Us, - All Rights Reserved.