Compound in marine sponges boost immune response to COVID-19 vaccine: Study
Beijing: Scientists have identified a compound in marine sponges that boosted the immune response to an experimental COVID-19 shot in mice by 25 times, compared to injection with the vaccine alone.
The ingredient can act as an adjuvant which can be added to vaccines to help elicit a more robust immune response, better training the body to fight infection.
The researchers from Huazhong Agricultural University, China noted that the tried-and-true strategy of using proteins from the pathogen can produce vaccines that are less expensive to make and easier to store.
However, many currently available inoculations against other diseases depend on proteins or pieces of them, and these shots contain adjuvants to boost their effectiveness.
The latest study, published on Wednesday in the journal ACS Infectious Diseases, found that molecules derived from a-galactosylceramide (aGC), a compound from marine sponges, can act as adjuvants.
These compounds work by stimulating a small population of immune cells that are important for defending the body against viral infections.
The researchers wanted to see if they could devise a version of aGC to significantly enhance the immune response elicited by a protein-based COVID-19 vaccine.
They added four analogs of aGC separately to an experimental vaccine containing a piece of SARS-CoV-2’s spike protein, which the virus uses to enter and infect cells. Mice were given three injections over 29 days and the researchers tracked their immune response up to 35 days.
To measure the effects of the adjuvants, the scientists scrutinised various aspects of immune function.
This included two ways the immune system eliminates pathogens: through T cells, which kill diseased cells, and antibodies, which are immune proteins that latch onto an invader.
None of the four meaningfully boosted the T cell response, but all of them produced antibodies with a much greater capacity for interfering with the virus.
The analog called aGC-CPOEt led to the production of antibodies with the greatest neutralising capacity — 25 times greater than what the vaccine could elicit without an adjuvant.
According to the researchers, these results suggest aGC-CPOEt merits further investigation as a potential adjuvant to fight COVID-19 and other infectious diseases.