Lymph nodes in our bodies are sites of activation of cells involved in disease-fighting antibodies. Antigens are molecules that trigger antibody response—a sort of siren for soldiers to come out and fight the invaders. You can develop antigens that can prod the immune system into producing antibodies. But how to take the antigens to the lymph nodes?
Researchers at the Indian Institute of Science, Bengaluru, have developed an antigen that can hitch-hike on a natural protein called serum albumin in blood and ride all the way to the nearest lymph node.
This development opens up a new way to bring out cancer vaccines, says a write-up put up on IISc website.
Cancer cells are very clever—they shut down the production of antibodies that target and eliminate them. Developing a cancer vaccine, therefore, “involves modifying or creating a mimic of an antigen found on the surface of cancer cells to turn up or turn on this antibody production,” says the article. In recent years, scientists have turned to carbohydrates found on cancer cell surfaces to develop these antigens.
“Carbohydrate-based antigens have enormous importance and relevance in cancer vaccine development,” explains N Jayaraman, Professor at the Department of Organic Chemistry and senior author of the study published in Advanced Healthcare Materials. “One major reason is that both normal and abnormal [cancer] cells have large amounts of carbohydrates coating their surfaces. But the abnormal cells carry carbohydrates that are very heavily truncated.”
Scientists have earlier tried ferrying such antigens into the body using an artificial protein or virus particle as the carrier. But these carriers can be bulky, lead to side-effects, and sometimes reduce antibody production against cancer cells. The IISc team, instead, decided to exploit the carrying ability of a natural protein called serum albumin, the most abundant protein in blood plasma.
To design the compound, Jayaraman and his PhD student, Keerthana TV, zeroed in on a truncated carbohydrate called Tn found on the surface of a variety of cancer cells, and synthesised it in the lab. Then, they combined it with a long-chain, oil-loving chemical – unlike carbohydrates which are water-loving – to form bubble-like micelles. They found that the combination is able to bind strongly to human serum albumin.
“The moment it latches on to albumin, the micelle breaks, and all the individual [antigen] molecules bind to the available albumin,” Jayaraman explains. “This opens up the idea that one doesn’t necessarily need to search for a virus or a protein or other types of carriers. Serum albumin is sufficient to carry it forward.”
Powering the future of sodium-ion batteries
In a lithium-ion battery, a compound of lithium is the cathode (electron donor) and graphite is the anode (electron acceptor). Sodium-ion batteries are considered among the alternatives for lithium-ion based ones—sodium, unlike lithium, is available everywhere. But the sodium-ion is bigger than lithium-ion, it does not easily go and embed itself within the graphene-layered structure of graphite-based electrodes.
A group of Italian scientists have suggested that biomass-derived biochar (BC) might be a good alternative to graphite. BC has “highly disordered and microporous carbons, known as ‘hard carbons’ and are considered the anode material of choice for sodium-ion batteries,” they say in a paper published in Renewable and Sustainable Reviews.