Antibodies protection against harmful forms of fungi in the intestine can be disrupted in some patients with Crohn’s disease, a condition caused by chronic inflammation of the intestine, according to a new study by researchers at Weill Cornell Medicine. ..

Previous studies have shown that the immune system plays an important role in maintaining a healthy balance of gut bacteria.The new study was published on November 22nd Nature microbiology, Senior author Iliyan Iliev, associate professor of immunology in medicine, and his team investigated whether it could also play a role in the management of intestinal fungi.

Unlike bacteria, fungi can change shape depending on environmental conditions, and certain forms are harmful to humans. In particular, a type of fungus called Candida albicans changes from a non-pathogenic yeast type to a type that produces hyphae that can invade tissues and cause damage.

Researchers have found that antibodies secreted in the intestine help control the etiology of candida albicans in healthy people, disabling this protective mechanism in people with Crohn’s disease and harmful overgrowth of pathogenic fungi. I have discovered that it can cause. Candida albicans intestinal excess is associated with inflammatory bowel disease and several other conditions that directly or indirectly affect the gastrointestinal tract.

“Anti-intestinal antibodies are involved in maintaining certain intestinal fungi, such as Candida albicans, in a benign, so-called symbiotic form,” said Iriev, a scientist at the Zil Roberts Institute for Inflammatory Intestines. I found that. ” Weil Cornell Medical illness. “This process is interrupted in patients with Crohn’s disease.”

In their experiments, researchers found that an antibody called secretory immunoglobulin A (slgA) in the feces of healthy mice selectively binds to the form of C. albicans in hyphae and stops its spread. discovered. They also found that these antibodies also bind to the hyphae of healthy human feces.

“These antibodies preferentially bind to the hyphae,” said Itai Delon, a PhD student in the lab. Specifically, they bind to sites on the hyphae and produce the virulence factors that these fungi use to harm host tissues. However, the antibody does not preferentially bind to harmless yeast. This suggests that antibodies may help the body maintain a healthy balance of intestinal fungi by preventing the inheritance of harmful forms of fungi.

Researchers also found that patients with Crohn’s disease, who develop severe inflammation of the colon and small intestine, have higher levels of antifungal antibodies in their blood compared to healthy adults. However, these antibodies do not appear to be secreted at high levels in the intestine to counter Candida albicans hyphae. Samples from the colon of these patients reveal an excess of fungi with hyphae.

“Impairment of this regulatory mechanism in mice and patients with Crohn’s disease can contribute to increased hyphal growth in the intestine,” Iriev said.

When researchers added antifungal antibodies to human cells grown in culture with C. albicans, the fungi produced fewer hyphae.

“These antifungal antibodies appear to have some degree of” disarmament “in the hyphae,” Delon said.

The result is that the therapeutic search for antifungal antibodies can be C. It suggests that it may be a way to help patients who develop overgrowth of albicans. Not all patients with this inflammatory bowel disease have overgrowth of this type of fungus, but some may be an important cause of the disease, Iriev said.

“The intestinal fungi in the gut, especially the Candida albicans community, form our immunity,” Iriev said. “We are developing these antibodies and they appear to play a protective role in certain situations.”

Researchers at the University of Central Florida have developed a device that detects viruses such as SARS-COV-2 in the body more accurately and as quickly as the rapid detection tests commonly used today.

Optical sensors use nanotechnology to accurately identify viruses in seconds. Blood sample..Researchers say the device can tell if someone has it with 95% accuracy virusSignificant improvements to the current rapid testing, which experts warn, may be less accurate. Testing for the virus is important for early treatment and prevention of the spread of the virus.

The results are detailed in a new study in the journal Nano letter..

Researchers tested the device with a sample of dengue virus, a mosquito-borne pathogen that causes dengue fever and poses a threat to people in the tropics. However, this technology can be easily adapted to detect other viruses such as SARS-COV-2, says Debashis Chanda, a professor at UCF’s NanoScience Technology Center, co-author of the study. ..

“High-sensitivity optical sensors, along with the rapid manufacturing approach used in this task, can transform this promising technology with a high degree of specificity and accuracy for detection of any virus, including SARS-COV-2 and its mutations. I promise, “says Chanda. “Here we have demonstrated a reliable technique that combines a genetic code such as PCR with an optical system on a chip to accurately detect the virus directly from the blood.”

This device closely matches the accuracy of gold standard PCR-based tests, but with near-instantaneous results rather than days of reception. Its accuracy is significantly improved over the current rapid antigen test warned by the U.S. Food and Drug Administration and the Centers for Disease Control and Prevention, and is inaccurate if the viral load is low or if the test instructions are not followed correctly. Results may occur.

The device works with a gold nanoscale pattern that reflects the virus’s signature that is set to detect on blood samples. Different viruses can be detected by using different DNA sequences that selectively target a particular virus.

The key to device performance is the ability to detect viruses directly from blood samples without the need for sample preparation or purification. This speeds up testing and improves accuracy.

“Most of the biosensor demonstrations in the literature use buffers as a test matrix to contain targeted analytes,” says Chanda. “But these approaches are not practical in real-world applications. Complex body fluids containing target biomarkers, such as blood, are the main cause of sensing, while at the same time the main cause of protein contamination leading to sensor failure. Because it is the cause. “

Researchers have confirmed the effectiveness of the device in multiple tests using different viral concentration levels and solution environments, including the presence of non-target viral biomarkers.

Abraham Vazquez Guardard, a postdoc at Northwestern University who was the lead author of the study and worked as a postdoctoral student in Chanda’s lab, said he was excited about the possibility.

“There was a previous demonstration of optical biosensing with human serum, but it requires offline complex and dedicated sample preparation by skilled personnel. This is a product not available in regular point of care applications.” Vazquez-Guardado says. “This study demonstrates for the first time an integrated device that separates plasma from blood and detects target viruses without pretreatment, with potential for practical use in the near future.”

According to Chanda, the next step in the study will include adapting the device to detect more viruses.