1. Loss of HIV candidate vaccine efficacy in male macaques by mucosal nanoparticle immunization rescued by V2-specific response.
- Author
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Rahman MA, Bissa M, Scinto H, Howe SE, Sarkis S, Ma ZM, Gutowska A, Jiang X, Luo CC, Schifanella L, Moles R, Silva de Castro I, Basu S, N'guessan KF, Williams LD, Becerra-Flores M, Doster MN, Hoang T, Choo-Wosoba H, Woode E, Sui Y, Tomaras GD, Paquin-Proulx D, Rao M, Talton JD, Kong XP, Zolla-Pazner S, Cardozo T, Franchini G, and Berzofsky JA
- Subjects
- Animals, Male, Simian Immunodeficiency Virus immunology, Vaccine Efficacy, Macaca mulatta, Simian Acquired Immunodeficiency Syndrome prevention & control, Simian Acquired Immunodeficiency Syndrome immunology, Dendritic Cells immunology, Immunization methods, SAIDS Vaccines immunology, SAIDS Vaccines administration & dosage, HIV Infections prevention & control, HIV Infections immunology, Vaccination methods, Nanoparticles administration & dosage, AIDS Vaccines immunology, AIDS Vaccines administration & dosage, Immunity, Mucosal immunology
- Abstract
Systemic vaccination of macaques with V1-deleted (ΔV1) envelope immunogens reduce the risk of SIV
mac251 acquisition by approximately 60%, with protective roles played by V2-specific ADCC and envelope-specific mucosal IL-17+ NKp44+ innate lymphoid cells (ILCs). We investigated whether increased mucosal responses to V2 benefit vaccine efficacy by delivering oral nanoparticles (NPs) that release V2-scaffolded on Typhoid Toxin B (TTB) to the large intestine. Strikingly, mucosal immunization of male macaques abrogated vaccine efficacy with control TTB or empty NPs, but vaccine efficacy of up to 47.6% was preserved with V2-TTB NPs. The deleterious effects of NPs were linked to preferential recruitment of mucosal plasmacytoid dendritic cells (pDCs), reduction of protective mucosal NKp44+ ILCs, increased non-protective mucosal PMA/Ionomycin-induced IFN-γ+ NKG2A- NKp44- ILCs, and increased levels of mucosal activated Ki67+ CD4+ T cells, a potential target for virus infection. V2-TTB NP mucosal boosting rescued vaccine efficacy, likely via high avidity V2-specific antibodies mediating ADCC, and higher frequencies of mucosal NKp44+ ILCs and of ∆V1gp120 binding antibody-secreting B cells in the rectal mucosa. These findings emphasize the central role of systemic immunization and mucosal V2-specific antibodies in the protection afforded by ΔV1 envelope immunogens and encourage careful evaluation of vaccine delivery platforms to avoid inducing immune responses favorable to HIV transmission., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)- Published
- 2024
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