Neurotoxic snail venom helps researchers better understand the immune system

Slow-moving, seafaring cone snails paralyze their unsuspecting prey using a harpoon-like tooth to deliver a suite of neurotoxic peptides. These conotoxins have an array of biological activity and bind to a variety of receptors in the vertebrate nervous system. Some of these receptors are also in the immune system, but little is known about how conotoxins affect cells outside the nervous system. To fill in this gap, a team of scientists led by James X. Hartmann of Florida Atlantic University and Frank Marí of NIST investigated immune cell responses to ImI, an α-conotoxin that inhibits α7 nicotinic acetylcholine receptors. The researchers cultured immune cells, exposed them to a bacterial toxin to induce inflammation, then added ImI to observe how it altered the inflammatory response. ImI exposure boosted production of two signaling molecules, TNF-α and IL-8, which play a role in launching an immune response (Sci. Rep. 2017, DOI: 10.1038/s41598-017-11586-2). This work identifies “an important overlap between the immune and central nervous systems in humans,” Marí says. Understanding how other conotoxins interact with immune receptors could aid in developing drug therapies to help the immune system target cancer cells or control bacterial infections, he adds.