Influenza-specific antibody-dependent phagocytosis

Fernanda Ana-Sosa-Batiz, Hillary Vanderven, S Jegaskanda, Angus Johnston, Steve Rockman, Karen L Laurie, Ian G Barr, Patrick C Reading, Marit Lichtfuss, Stephen J Kent

Research output: Contribution to journalArticleResearchpeer-review

49 Citations (Scopus)


Background: Immunity to human influenza A virus (IAV) infection is only partially understood. Broadly non-neutralizing antibodies may assist in reducing disease but have not been well characterized.

Methods: We measured internalization of opsonized, influenza protein-coated fluorescent beads and live IAV into a monocytic cell line to study antibody-dependent phagocytosis (ADP) against multiple influenza hemagglutinin (HA) subtypes. We analyzed influenza HA-specific ADP in healthy human donors, in preparations of intravenous immunoglobulin (IVIG), and following IAV infection of humans and macaques.

Results: We found that both sera from healthy adults and IVIG preparations had broad ADP to multiple seasonal HA proteins and weak cross-reactive ADP to non-circulating HA proteins. The ADP in experimentally influenza-infected macaque plasma and naturally influenza-infected human sera mediated phagocytosis of both homologous and heterologous IAVs. Further, the IAV phagocytosed in an antibody-mediated manner had reduced infectivity in vitro.

Conclusion: We conclude that IAV infections in humans and macaques leads to the development of influenza-specific ADP that can clear IAV infection in vitro. Repeated exposure of humans to multiple IAV infections likely leads to the development of ADP that is cross-reactive to strains not previously encountered. Further analyses of the protective capacity of broadly reactive influenza-specific ADP is warranted.
Original languageEnglish
Article numbere0154461
Pages (from-to)1 - 18
Number of pages18
JournalPLoS ONE
Issue number4
Publication statusPublished - 2016

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