Authors: Martha Powell, Future Science Group
New studies on Xenopus laevis have suggested that altering transmembrane potential in host cells may improve resistance to infections. This reveals a novel aspect of the innate immune system, and the researchers hope it could present a new approach for fighting infections in a clinical setting.
The researchers, from Tufts University (MA, USA), discovered that in tadpoles administering compounds, or inducing ion channels, to depolarize cells strengthened their response to Escherichia coli infection.
Transmembrane potential is known to play critical functions in many cell types, causing the researchers to hypothesize it may also have a function in immunity. The study, published recently in npj Regenerative Medicine, therefore investigated the effects of depolarizing or hyperpolarizing compounds on embryonic, E. coli-infected Xenopus laevis.
The team observed that depolarization, with the compound ivermectin, increased the embryo’s ability to resist bacterial infection by an average of 32% compared with controls. The researchers then confirmed this by injected the tadpoles with mRNA encoding ion channels that would depolarize their cells, validating the drug results.
In contrast, the team discovered that hyperpolarizing ion channels, or compounds, reduced the ratio of embryos that survived by approximately 20%.
Author Michael Levin, Tufts University, concluded: “All cells, not just nerve cells, naturally generate and receive electrical signals. Being able to regulate such non-neural bioelectricity with the many ion channel and neurotransmitter drugs that are already human-approved gives us an amazing new toolkit to augment the immune system’s ability to resist infections.”
Source: Pare JF, Martyniuk CJ, Levin M. Bioelectric regulation of innate immune system function in regenerating and intact Xenopus laevis. npj Regenerative Medicine. doi:10.1038/s41536-017-0019-y (2017) (Epub ahead of print); www.eurekalert.org/emb_releases/2017-05/tu-bnw051917.php