Immune responses and biofilms on painful polypropylene mesh

  • Research type

    Research Study

  • Full title

    Microbial communities, biofilms, and immune responses in pain-associated and non-pain associated polypropylene meshes

  • IRAS ID

    359769

  • Contact name

    Fiona Reid

  • Contact email

    fiona.reid@mft.nhs.uk

  • Sponsor organisation

    University of Manchester

  • Duration of Study in the UK

    2 years, 0 months, 6 days

  • Research summary

    This study explores why some women develop chronic pain after surgery using a polypropylene mesh mid-urethral sling (PMMUS) to treat stress urinary incontinence (SUI). Although PMMUS is sterilised before use, we have found bacteria growing on mesh removed from women who experienced pain. These bacteria form structures called biofilms, which can be difficult to detect and may trigger long-lasting inflammation—even when standard tests show no clear signs of infection.

    We believe that bacteria from the vagina or urine may contaminate the mesh during surgery and form biofilms that lead to abnormal immune reactions. These immune responses may be responsible for pain in some women.

    To test this, we will recruit 24 women having surgery for SUI and collect urine and vaginal samples before and six months after surgery to analyse changes in their microbiome (the community of bacteria living in the body).

    We will also analyse the body’s immune response to the mesh-biofilm combinations of 24 women having their PMMUS removed due to pain. We will do this using a range of laboratory techniques, such as microscopy, immune cell profiling, and single cell RNA sequencing, which tells us what different immune cells are doing. We will compare the findings with mesh removed from 24 women who did not experience pain, but instead due to mechanical failure.

    All recruitment will take place in St Mary's Hospital (MFT), over 2 years. All laboratory work will take place in Stopford Building, UoM, over 3 years.

    Our aim is to find patterns in the bacteria and immune responses linked to pain. This could help predict which patients might develop pain, improve mesh design or surgical techniques, and potentially lead to non-surgical treatments to relieve pain.

    This research could ultimately help make mesh surgery safer and improve outcomes for women with SUI and other conditions treated using surgical mesh implants.

  • REC name

    North West - Preston Research Ethics Committee

  • REC reference

    25/NW/0322

  • Date of REC Opinion

    4 Dec 2025

  • REC opinion

    Further Information Favourable Opinion