Heterogeneity of T Cell Responses to Pandemic pH1N1 Monovalent Vaccine in HIV-Infected Pregnant Women

AIDS Res Hum Retroviruses. 2015 Nov;31(11):1170-7. doi: 10.1089/aid.2015.0151. Epub 2015 Aug 31.


We investigated the Th1 protective and regulatory T and B cell (Treg and Breg) responses to pH1N1 monovalent influenza vaccine (IIV1) in HIV-infected pregnant women on combination antiretroviral therapy (cART). Peripheral blood mononuclear cells (PBMCs) from 52 study participants were cryopreserved before and after vaccination and analyzed by flow cytometry. pH1N1-specific Th1, Treg, and Breg responses were measured in PBMCs after in vitro stimulation with pH1N1 and control antigen. The cohort analysis did not detect changes in pH1N1-Th1, Treg, or Breg subsets postvaccination. However, individual analyses distinguished subjects who mounted vigorous Th1 responses postvaccination from others who did not. Postvaccination, high pH1N1-Th1 correlated with high pH1N1-Treg and Breg responses, suggesting that low influenza effector responses did not result from excessive vaccine-induced immune regulation. High postvaccination pH1N1-Th1 responses correlated with baseline high PHA- and pH1N1-IFN-γ ELISpot and circulating CD4(+)CD39(+)% and CD8(+)CD39(+)% Treg, with low CD8(+) cell numbers and CD19(+)FOXP3(+)% Breg, but not with CD4(+) cell numbers or HIV viral load. These data highlight the heterogeneity of T cell responses to vaccines in HIV-infected individuals on cART. Predictors of robust Th1 responses to IIV include CD8(+) cell numbers, T cell functionality, and circulating Breg and Treg.

Publication types

  • Clinical Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Anti-Retroviral Agents / therapeutic use
  • B-Lymphocytes / immunology
  • Cohort Studies
  • Enzyme-Linked Immunospot Assay
  • Female
  • Flow Cytometry
  • HIV Infections / complications*
  • HIV Infections / drug therapy
  • Humans
  • Influenza A Virus, H1N1 Subtype / immunology*
  • Influenza Vaccines / administration & dosage
  • Influenza Vaccines / immunology*
  • Influenza, Human / prevention & control*
  • Interferon-gamma / metabolism
  • Lymphocyte Subsets / immunology*
  • Pregnancy
  • Pregnancy Complications, Infectious*
  • T-Lymphocytes / immunology*
  • Viral Load
  • Young Adult


  • Anti-Retroviral Agents
  • Influenza Vaccines
  • Interferon-gamma