Early in the COVID-19 pandemic, doctors recognized that patients who developed a "cytokine storm"—a surge of pro-inflammatory immune proteins—were often the sickest and at highest risk of dying. But a cytokine storm can also occur in other illnesses, such as influenza.
At the spring meeting of the American Chemical Society (ACS), scientists report preliminary results on a sweat sensor that acts as an early warning system for an impending cytokine storm, which could help doctors more effectively treat patients.
For their new cytokine sensor (called the SWEATSENSER Dx), the researchers made sensor strips with antibodies against seven pro-inflammatory proteins: interleukin-6 (IL-6), IL-8, tumor necrosis factor-α (TNF-α), TNF-related apoptosis-inducing ligand, IL-10, interferon-γ-induced protein-10 and C-reactive protein. They inserted the strips into their device and, in a small observational study, they tested them on six healthy people and five people with influenza. Two of the sick people showed elevated cytokine levels, and in all participants, cytokines in passive sweat correlated with levels of the same proteins in serum.
The SWEATSENSER Dx was even sensitive enough to measure cytokines in patients taking anti-inflammatory drugs, who excrete cytokines in the low-picogram-per-milliliter concentration range. The device tracked cytokine levels for up to 168 hours before the sensor strip needed to be replaced.
EnLiSense, in partnership with the researchers, is now planning clinical trials of the cytokine sensor in people with respiratory infections.
"Access to COVID-19 patients has been a challenge because healthcare workers are overwhelmed and don't have time to test investigational devices," says Shalini Prasad, the project's principal investigator "But we're going to continue to test it for all respiratory infections because the disease trigger itself doesn't matter—it's what's happening with the cytokines that we're interested in monitoring."
Photo: A wristwatch-like device measures cytokine levels in passive sweat. Credit: Kai-Chun Lin