TOP MEDICAL NEWS 08/AUGUST/2022

For the first time, scientists have designed a phage combination therapy that can precisely target and suppress gut bacteria associated with inflammatory bowel diseases (IBD).

Elinav et. al compared the gut microbiota compositions of 537 IBD patients to healthy controls enrolled in cohort studies in France, Israel, the U.S., and Germany. The team found IBD patients, despite their differences in geography, ethnicity, and diet, tend to have a group of Klebsiella pneumonia (Kp) strains enriched in their gut, especially in those who are experiencing disease flare-ups. When transplanting the Kp into mice, the team found that mice developed severe intestinal inflammation and tissue damage, suggesting that these Kp strains may contribute to the worsening of IBD.

Next, Elinav and his team scanned and isolated thousands of bacteriophages from environmental samples. Bacteriophages are viruses that can target and infect bacteria. They identified some 40 phages that appear to be effective against the IBD-contributing Kp strains, including strains that have already developed phage resistance.

Ref:

Eran Elinav et. al, Targeted suppression of human IBD-associated gut microbiota commensals by phage consortia for treatment of intestinal inflammation, Cell, 4-Aug-2022, 10.1016/j.cell.2022.07.003

2. A new and easy rapid test to easily diagnose Cancers and heart disease

Imperial researchers have built a new easy-to-use test that could diagnose non-infectious diseases like heart attacks and cancers more quickly.

The new test works by detecting molecular signals in the body called biomarkers, which are already used in things like COVID-19 testing where the presence of SARS-CoV-2 genes indicates COVID-19. There are also biomarkers for non-infectious diseases: for example, prostate-specific antigen (PSA) in the blood can sometimes act as a biomarker to indicate the presence of prostate cancer.

The new test, called CrisprZyme, has been developed by a team of researchers led by Imperial College London, MIT, and Max Delbrück Center for Molecular Medicine in Berlin.

CrisprZyme builds on CRISPR diagnostic tests, which use RNA to detect biomarkers in biological fluids like blood or urine. In their current form, these tests detect RNA and then amplify this RNA by creating many copies so that the signal is easier to read.

Ref:

Dr. Marta Broto et. al, 'Nanozyme-catalysed CRISPR assay for preamplification-free detection of non-coding RNAs, Nature Nanotechnology, 4-Aug-2022, DOI: 10.1038/s41565-022-01179-0

3. Distinct genomic characteristics of breast cancer in women with PTEN hamartoma tumor syndrome

Cleveland Clinic researchers have uncovered genomic characteristics of breast cancers associated with PTEN hamartoma tumor syndrome (PHTS) that differentiate them from sporadic breast cancers. The findings, published in the American Journal of Human Genetics, have important implications for the personalized management of PHTS-related breast cancers.

"PHTS-associated breast cancers often develop at a younger age and may progress more aggressively than their sporadic counterparts, but they are treated similarly, which underscores the need to better understand any underlining genomic differences between PHTS-associated and sporadic breast cancers."

To address this need, the researchers performed exome sequencing on samples from 44 women with germline PTEN mutations who developed breast cancer and compared the data to samples from women with sporadic breast cancers.

Ref:

Charis Eng et. al, Exome Sequencing Reveals a Distinct Somatic Genomic Landscape in Breast Cancer from Women with Germline PTEN Variants, American Journal of Human Genetics, 4-Aug-2022, DOI: 10.1016/j.ajhg.2022.07.005

4. Hyaluronic acid, a naturally occurring compound, which awakens stem cells to repair damaged muscle

A new study published in the journal Science reveals a unique form of cell communication that controls muscle repair.

Scientists have now shown that a natural substance called hyaluronic acid, which is used in cosmetics and injections for osteoarthritis, is the key molecule that manages this fundamental interaction.

"When muscles get damaged, it is important for immune cells to quickly enter the tissue and remove the damage before stem cells begin the repair," said Dr. Jeffrey Dilworth, senior author of the study. "Our study shows that muscle stem cells are primed to start repair right away, but the immune cells maintain the stem cells in a resting state while they finish the cleanup job. After about 40 hours, once the cleanup job is finished, an internal alarm goes off in the muscle stem cells that allows them to wake up and start repair."

Ref:

Dr. Jeffrey Dilworth et. al, JMJD3 activated hyaluronan synthesis drives muscle regeneration in an inflammatory environment, Science, 4-Aug-2022, DOI: 10.1126/science.abm9735