AUTHOR=Gingerich Aaron , Mahoney Lauren , McCormick Anna L. , Miller Rose J. , Mousa Jarrod 

TITLE=Human monoclonal antibodies protect against viral-mediated pneumococcal superinfection

JOURNAL=Frontiers in Immunology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2024.1364622

DOI=10.3389/fimmu.2024.1364622

ISSN=1664-3224

ABSTRACT=<sec><title>Introduction</title><p>Community-acquired pneumonia (CAP) is a global health concern, with 25% of cases attributed to <italic>Streptococcus pneumoniae</italic> (<italic>Spn</italic>). Viral infections like influenza A virus (IAV), respiratory syncytial virus (RSV), and human metapneumovirus (hMPV) increase the risk of <italic>Spn</italic>, leading to severe complications due to compromised host immunity.</p></sec><sec><title>Methods</title><p>We evaluated the efficacy of an anti-PhtD monoclonal antibody (mAb) cocktail therapy (PhtD3 + 7) in improving survival rates in three viral/bacterial coinfection models: IAV/<italic>Spn</italic>, hMPV/<italic>Spn</italic>, and RSV/<italic>Spn</italic>.</p></sec><sec><title>Results</title><p>The PhtD3 + 7 mAb cocktail outperformed antiviral mAbs, resulting in prolonged survival. In the IAV/<italic>Spn</italic> model, it reduced bacterial titers in blood and lungs by 2-4 logs. In the hMPV/<italic>Spn</italic> model, PhtD3 + 7 provided greater protection than the hMPV-neutralizing mAb MPV467, significantly reducing bacterial titers. In the RSV/<italic>Spn</italic> model, PhtD3 + 7 offered slightly better protection than the antiviral mAb D25, uniquely decreasing bacterial titers in blood and lungs.</p></sec><sec><title>Discussion</title><p>Given the threat of antibiotic resistance, our findings highlight the potential of anti-PhtD mAb therapy as an effective option for treating viral and secondary pneumococcal coinfections.</p></sec>