Dual induction of tissue-resident T and B cell immunity for broad influenza protection with a nanofiber-VLP vaccine.

Respiratory pathogens pose significant global health challenges, with current vaccines often failing to prevent viral replication at mucosal entry points. To address this, we developed an adjuvant-free intranasal nanovaccine (NP@HA-VLP-Q11) by integrating SpyTag/SpyCatcher-mediated antigen multimerization on virus-like particles (VLPs) with self-assembling Q11 nanofibers. This vaccine leverages the ability of Q11 to induce both humoral and cellular immunity without requiring supplemental adjuvants or eliciting local inflammation to co-deliver a conserved nucleoprotein (NP) CD8+ T cell epitope and influenza hemagglutinin stem domain (miniHA) VLPs. In mouse models, we show that NP@HA-VLP-Q11 elicits systemic neutralizing antibodies and lung-resident memory T cells (TRMs) and B cells (BRMs) that are maintained for at least 12 weeks after immunization and expand rapidly upon heterologous H9N2 challenge. Importantly, intranasal immunization with NP@HA-VLP-Q11 conferred immunity and cross-protection against heterologous influenza strains that were preserved for at least 12 weeks. The dual induction of TRMs and BRMs offers immediate humoral protection and sustained cellular immunity at the infection site, mimicking natural viral exposure while avoiding replication risks. These findings demonstrate the potential of self-assembling nanomaterials combined with stabilized multimerized antigens in VLPs to create next-generation vaccines for broad, broad and effective protection against respiratory pathogens.