UNI-MB - logo
UMNIK - logo
 
E-resources
Full text
Peer reviewed Open access
  • The ARDS microenvironment e...
    Tunstead, Courteney; Volkova, Evelina; Dunbar, Hazel; Hawthorne, Ian J.; Bell, Alison; Crowe, Louise; Masterson, Joanne C.; Dos Santos, Claudia C.; McNicholas, Bairbre; Laffey, John G.; English, Karen

    Molecular therapy, 08/2024
    Journal Article

    Clinical trials investigating the potential of mesenchymal stromal cells (MSCs) for the treatment of inflammatory diseases, such as acute respiratory distress syndrome (ARDS), have been disappointing, with less than 50% of patients responding to treatment. Licensed MSCs show enhanced therapeutic efficacy in response to cytokine-mediated activation signals. There are two distinct sub-phenotypes of ARDS: hypo- and hyper-inflammatory. We hypothesized that pre-licensing MSCs in a hyper-inflammatory ARDS environment would enhance their therapeutic efficacy in acute lung inflammation (ALI). Serum samples from patients with ARDS were segregated into hypo- and hyper-inflammatory categories based on interleukin (IL)-6 levels. MSCs were licensed with pooled serum from patients with hypo- or hyper-inflammatory ARDS or healthy serum controls. Our findings show that hyper-inflammatory ARDS pre-licensed MSC conditioned medium (MSC-CMHyper) led to a significant enrichment in tight junction expression and enhanced barrier integrity in lung epithelial cells in vitro and in vivo in a vascular endothelial growth factor (VEGF)-dependent manner. Importantly, while both MSC-CMHypo and MSC-CMHyper significantly reduced IL-6 and tumor necrosis factor alpha (TNF-α) levels in the bronchoalveolar lavage fluid (BALF) of lipopolysaccharide (LPS)-induced ALI mice, only MSC-CMHyper significantly reduced lung permeability and overall clinical outcomes including weight loss and clinical score. Thus, the hypo- and hyper-inflammatory ARDS environments may differentially influence MSC cytoprotective and immunomodulatory functions. Display omitted English and colleagues investigated the differential impact of the hypo- and hyper-inflammatory ARDS patient microenvironment on human bone marrow-derived mesenchymal stromal cells (MSCs). While both hypo- and hyper-inflammatory ARDS licensing enhanced MSC immunomodulatory function, only the hyper-licensed MSC secretome promoted lung barrier reparation post-endotoxin challenge in a VEGF-dependent manner.