AUTHOR=Nyazika Tinashe K. , Sibale Lusako , Phiri Joseph , De Ste Croix Megan , Jasiunaite Zydrune , Mkandawire Christopher , Malamba Rose , Kankwatira Anstead , Manduwa Miriam , Ferreira Daniela M. , Nyirenda Tonney S. , Oggioni Marco R. , Mwandumba Henry C. , Jambo Kondwani C. 

TITLE=Intracellular survival of Streptococcus pneumoniae in human alveolar macrophages is augmented with HIV infection

JOURNAL=Frontiers in Immunology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2022.992659

DOI=10.3389/fimmu.2022.992659

ISSN=1664-3224

ABSTRACT=<p>People Living with HIV (PLHIV) are at an increased risk of pneumococcal pneumonia than HIV-uninfected adults, but the reasons for this are still not well understood. We investigated whether alveolar macrophages (AM) mediated control of pneumococcal infection is impaired in PLHIV compared to HIV-uninfected adults. We assessed anti-bactericidal activity against <italic>Streptococcus pneumoniae</italic> of primary human AM obtained from PLHIV and HIV-uninfected adults. We found that pneumococcus survived intracellularly in AMs at least 24 hours post <italic>ex vivo</italic> infection, and this was more frequent in PLHIV than HIV-uninfected adults. Corroborating these findings, <italic>in vivo</italic> evidence showed that PLHIV had a higher propensity for harboring <italic>S. pneumoniae</italic> within their AMs than HIV-uninfected adults. Moreover, bacterial intracellular survival in AMs was associated with extracellular propagation of pneumococcal infection. Our data suggest that failure of AMs to eliminate <italic>S. pneumoniae</italic> intracellularly could contribute to the increased risk of pneumococcal pneumonia in PLHIV.</p>