T cell help for B cells may be perturbed in people living with HIV (PLWH), even when HIV is suppressed, as evidenced by reports of suboptimal responses to influenza vaccination. We investigated cTFH responses to the 2017–18 inactivated quadrivalent influenza vaccine (QIV) in men living with antiretroviral therapy (ART)-suppressed HIV infection who were treated in the early or chronic phase of infection, and control subjects. Here we show that seroprotective antibody responses in serum and oral fluid correlated with cTFH activation and were equivalent in all three groups, irrespective of when ART was started. These responses were attenuated in those reporting immunisation with influenza vaccine in the preceding three years, independent of HIV infection. Measurement of influenza-specific IgG in oral fluid was closely correlated with haemagglutination inhibition titre. T-SNE and two-dimensional analysis revealed a subset of CD4+CXCR3+CXCR5+ cTFH activated at one week after vaccination. This was distinguishable from cTFH not activated by vaccination, and a rare, effector memory CD4+CXCR5hiCD32hi T cell subset. The data support the use of QIV for immunisation of PLWH, reveal distinct circulating CD4+CXCR5+ T cell subsets and demonstrate oral fluid sampling for influenza-specific IgG is an alternative to phlebotomy.
Bibliographical noteFunding Information:
K.M.P. reports grants from the National Institute for Health Research Imperial Biomedical Research Centre during the conduct of the study and grants from Gilead Sciences Europe Ltd. outside the submitted work. All other authors declare no competing interests.
The authors would like to thank the staff and patients of the Clinical Trials Centre, The Wharfside Clinic, Jefferiss Wing, Imperial College Healthcare NHS Trust, London, UK, the HEATHER study, and staff of the Respiratory Virus Unit, Virus Reference Department, Public Health England. In addition we would like to thank the staff of the Molecular Diagnostic Unit, Section of Virology, Imperial College London, UK. We would like to thank Dr John Tregoning for his assistance in shaping and editing the manuscript. K.M.P is a National Institute for Health Research Clinical Lecturer in Genitourinary and HIV medicine. This paper is independent research funded by the National Institute for Health Research (NIHR) Imperial Biomedical Research Centre (BRC). The views expressed in this publication are those of the author(s) and not necessarily those of the NHS, the National Institute for Health Research or the Department of Health.
© 2019, The Author(s).