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How mRNA vaccines work

Nutritional supplements potentially beneficial in COVID-19

Hospital Healthcare Europe 7 December, 2020   During the COVID-19 pandemic, sales of nutritional supplements known to have an important role in immune function such as vitamins C, D and the mineral, zinc, increased substantially. However, to date, no trials have shown evidence for a beneficial role of these supplements in COVID-19.

Major Depression Linked to Insulin Resistance

individuals experiencing a current episode of major depressive disorder (MDD) are significantly more likely to have insulin resistance (IR), new research shows. Investigators found patients with MDD were 51% more likely to have IR compared with their counterparts without the depressive disorder. In addition, in individuals experiencing current depression, IR was also associated with depression…

Inactivated vaccines Inactivated vaccines have been in use since the 1880s. The viruses in these vaccines have been rendered inactive by chemical treatment, as with SARS-CoV-2 candidate vaccines, or by physical treatment. With this type of vaccine, the immune system encounters the virus in its entirety. It can mount a defence when it detects the viral spike protein (also called spicule or S-protein), envelope and nucleoprotein. Currently, seven inactivated vaccine candidates are being tested in humans. Of these, three are in Phase 3 clinical trials. Unlike Phase 1 and Phase 2, which are used to evaluate a vaccine’s tolerability, safety and ability to induce an immune response, a Phase 3 clinical trial allows scientists to test its efficacy. Recombinant proteins Recombinant protein vaccines fall into two categories: subunit and virus-like particle vaccines. For subunit protein vaccines, a viral protein is produced in large quantities in a living “factory,” such as a bacterium, plant, mammalian or insect cell. When the viral protein is presented to the immune system, it triggers a reaction. The 13 subunit vaccine candidates currently in Phase 1, 2 or 3 clinical trials are composed of either the entire spike protein or a specific portion of the spike protein called the ‘receptor binding domain’. Virus-like particle vaccines are composed of a set of viral proteins that mimic the shape of the virus. This particle “pseudo-virus” is an empty shell, devoid of genetic material and non-infectious, but this does not prevent the immune system from recognizing it. Viral vector vaccines This approach is based on using a virus that is non-pathogenic or of little danger to humans. In the case of the 12 vaccine candidates of this type currently being studied in humans, the viral vectors are mostly adenoviruses. They represent a large group of viruses that can cause colds and conjunctivitis, among other symptoms. Used as Trojan horses, these viruses are modified to express the SARS-CoV-2 spike protein following vaccination. Viral vector vaccines are a recent strategy, but were used in the development of the Ebola virus vaccine. RNA and DNA vaccines Despite differences in their composition, DNA and mRNA (messenger RNA) both contain genetic information for protein production. While an RNA molecule can directly produce that information, DNA requires an intermediate transcription step. RNA or DNA vaccine candidates differ from other strategies in two ways. First, it is a novel strategy: there is no RNA or DNA vaccine on the market. Second, they are the only vaccine candidates composed solely of genetic material. In the case of RNA vaccines, messenger RNA molecules are wrapped in lipid nanoparticles. Once the vaccine is injected, the RNA serves as a template for the body’s cells to produce a viral protein — the spike protein, to be precise. DNA vaccines, on the other hand, are made up of a circular DNA (called a plasmid). This DNA will be transcribed into RNA, which will again serve as a template. Six RNA vaccine candidates are currently being tested in humans, two of which are in Phase 3. The five DNA vaccine candidates are in Phase 1 and 2 clinical trials

Genetic material encoding the spike protein, which enables to infect human cells, is inserted into a modified cold virus from chimps. This combination is the Oxford-AstraZeneca vaccine that was then injected into volunteers. The vaccine allows the muscle cells in the arm to manufacture the spike protein, which gives the body a preview of the virus and allows it to develop an immune response should the real virus strike

HOW SOME OF THE COVID-19 VACCINES COMPARE

Metformin Improves Most Outcomes for T2D During Pregnancy

Women with type 2 diabetes who take metformin during pregnancy to control their blood glucose levels experience a range of benefits, including reduced weight gain, reduced insulin doses, and fewer large for gestational age babies, suggest the results of a randomized controlled trial.

Rapid COVID-19 breath test can help differentiate between other infections

With the onset of influenza season and the potential overlap of influenza and COVID-19 symptoms, there is a need to be able to quickly differentiate between the two viruses to ensure that patients are appropriately managed.

First SGLT1/2 Inhibitor Shows ‘Spectacular’ Phase 3 Safety and Efficacy in T2D

Sotagliflozin, a novel type of sodium-glucose cotransporter inhibitor, showed the diverse benefits this drug class provides along with some new twists in a pair of international pivotal trials that together enrolled nearly 12,000 patients with type 2 diabetes

Can Autoimmune Antibodies Explain Blood Clots in COVID-19?

Caption: Illustration showing a blood vessel with a platelet clot (yellow). Red blood cells (red), neutrophils (purple), and Y-shaped antibodies called aPL (white) circulate through the vessel. Credit: Stephanie King/Michigan Medicine For people with severe COVID-19, one of the most troubling complications is abnormal blood clotting that puts them at risk of having a debilitating…