A modified porous silicon microparticle promotes mucosal delivery of SARS-CoV-2 antigen and induction of potent and durable systemic and mucosal T helper 1 skewed protective immunity

Adam, A.; Shi, Q.; Wang, B.; Zou, J.; Mai, J.; Osman, S. R.; Wu, W.; Xie, X.; Aguilar, P. V.; Bao, X.; Shi, P.-Y.; Shen, H.; Wang, T.

doi:10.1101/2021.11.22.469576

bioRxiv · 10.1101/2021.11.22.469576

A modified porous silicon microparticle promotes mucosal delivery of SARS-CoV-2 antigen and induction of potent and durable systemic and mucosal T helper 1 skewed protective immunity

Adam, A.·Shi, Q.·Wang, B.·Zou, J.·Mai, J.·Osman, S. R.·Wu, W.·Xie, X.·Aguilar, P. V.·Bao, X.·Shi, P.-Y.·Shen, H.·Wang, T.

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Abstract

Development of optimal SARS-CoV-2 vaccines to induce potent, long-lasting immunity and provide cross-reactive protection against emerging variants remains a high priority. Here, we report that a modified porous silicon microparticle (mPSM)-adjuvanted SARS-CoV-2 receptor-binding domain (RBD) vaccine activated dendritic cells and generated more potent and durable SARS-CoV-2-specific systemic humoral and type 1 helper T (Th) cell-mediated immune responses than alum-formulated RBD following parenteral vaccination, and protected mice from SARS-CoV-2 and Beta variant infection. mPSM facilitated the uptake of SARS-CoV-2 RBD antigens by nasal and airway epithelial cells. Parenteral and intranasal prime and boost vaccinations with mPSM-RBD elicited potent systemic and lung resident memory T and B cells and SARS-CoV-2 specific IgA responses, and markedly diminished viral loads and inflammation in the lung following SARS-CoV-2 Delta variant infection. Our results suggest that mPSM can serve as potent adjuvant for SARS-CoV-2 subunit vaccine which is effective for systemic and mucosal vaccination.

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Adam, A., Shi, Q., Wang, B., Zou, J., Mai, J., Osman, S. R., Wu, W., Xie, X., Aguilar, P. V., Bao, X., Shi, P.-Y., Shen, H., Wang, T.. 2021-11-24. A modified porous silicon microparticle promotes mucosal delivery of SARS-CoV-2 antigen and induction of potent and durable systemic and mucosal T helper 1 skewed protective immunity. https://doi.org/10.1101/2021.11.22.469576

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