In this study, researchers have found ways to improve our body’s immune response to a bacterial infection, without the need for antibiotics. Using the anti-histamine drug clemastine activates immune cells called macrophages to kill bacteria. This identifies a possible new treatment approach for certain infections, as an alternative to antibiotics, crucial as antibiotic-resistant bacteria is increasing worldwide. Antibiotics revolutionised the treatment of bacterial infections in the 1940s. Unfortunately, bacterial infections are becoming harder to treat using antibiotics because of the increase in antibiotic-resistant bacteria worldwide.A new approach, which aims at improving our own body’s immune response to infection, could be a useful addition or alternative to conventional antibiotics. However, due to the complexity of the immune response, it has been difficult to identify which elements to study as targets for potential treatments.In this study, researchers used a strategy that looked into which elements of the human immune response, harmful bacteria have managed to adapt and become resistant to. This would suggest that these elements might be particularly important in normally providing protection from harmful bacteria.They focused on an immune cell called a macrophage, which can engulf and kill bacteria. They found three new ways that macrophages kill the bacteria Streptococcus pneumoniae. These involved the genes:ACOD1 which produces an acid which directly killed bacteriaNAMPT which helps macrophages generate energyP2RX7 which regulates killing of bacteria via digestion after they have been engulfed.Following these findings, the researchers studied the anti-histamine drug clemastine, which has a ‘side effect’ unrelated to its anti-histamine effect, where it activates bacterial killing via the P2RX7 gene. They found that this drug could increase the ability of mice and zebrafish larvae to kill bacteria without a need for antibiotics. Bacteria are becoming resistant to antibiotics quicker than new antibiotics can be developed. Here, we’ve identified specific elements of the immune response that can be targeted with drugs to promote bacterial killing, without relying on antibiotics. Dr Clark Russell NES/CSO Postdoctoral Clinical Lecturer and paper’s first author Next, the researchers are applying this strategy to study other bacterial infections and will be investigating ways clemastine could be studied in humans as an alternative or addition to conventional antibiotics.This work was funded by Wellcome Trust, UK Research and Innovation Medical Research Council, Chief Scientist Office Scotland, European Crohn’s Colitis Organisation, National Science Centre of Poland and UK Biotechnology and Biological Sciences Research Council.Read the full paper in Science Advances Related linksRelated paper: The search for immune-based treatments for Staphylococcus aureus infectionsClark Russell University of Edinburgh Research ExplorerDockrell research groupSHIELD consortiumBaillie-Gifford Pandemic Science HubRoslin Institute Tags CIR Publication date 19 Feb, 2026
