Researchers tested a special extract from the Agaricus brasiliensis mushroom (rich in a compound called ergosterol) to treat severe sepsis, a life-threatening blood infection, in mice. When mice were given this mushroom extract alone, 67% survived, and when combined with antibiotics, 100% survived compared to none with saline alone. The extract reduced inflammation, protected the liver, fought bacteria, and reduced harmful free radicals in the body, suggesting it could be a valuable addition to antibiotic treatment for sepsis.