When the Mpox virus (MPXV) began spreading globally in 2022, it became critical to evaluate whether residual immunity from smallpox vaccination provided cross-protection. To assess the cross-immune response to MPXV, we collected serum samples (n = 97) and PBMCs (n = 30) from healthy-donors, either born before 1974 and reporting smallpox vaccination during childhood or born after 1975 and not vaccinated with Vaccinia virus (VACV)-based vaccines. We evaluated the levels of anti-MPXV IgG and neutralizing antibodies (Nabs) and the presence of a T cell response against MPXV. We found anti-MPXV IgG and Nabs in 60 (89.6%) and 40 (70.1%) vaccinated individuals, respectively. We observed a T cell response to Orthopoxviruses and MPXV peptide pools in 30% of vaccinated individuals. We thus show that a high proportion of subjects who received the smallpox vaccine 40 to 60 years ago have humoral cross-immunity, while the T-cell-specific response against MPXV was observed in a smaller group (30%) of vaccinated individuals. This study, combined with information on immunity developed during natural infection or the administration of current vaccines, will contribute to a better understanding of humoral and cellular responses against MPXV.
Evaluation of Cross-Immunity to the Mpox Virus Due to Historic Smallpox Vaccination / Matusali, Giulia; Petruccioli, Elisa; Cimini, Eleonora; Colavita, Francesca; Bettini, Aurora; Tartaglia, Eleonora; Sbarra, Settimia; Meschi, Silvia; Lapa, Daniele; Francalancia, Massimo; Bordi, Licia; Mazzotta, Valentina; Coen, Sabrina; Mizzoni, Klizia; Beccacece, Alessia; Nicastri, Emanuele; Pierelli, Luca; Antinori, Andrea; Girardi, Enrico; Vaia, Francesco; Sette, Alessandro; Grifoni, Alba; Goletti, Delia; Puro, Vincenzo; Maggi, Fabrizio. - In: VACCINES. - ISSN 2076-393X. - 11:10(2023). [10.3390/vaccines11101541]
Evaluation of Cross-Immunity to the Mpox Virus Due to Historic Smallpox Vaccination
Pierelli, Luca;Sette, Alessandro;Maggi, Fabrizio
2023
Abstract
When the Mpox virus (MPXV) began spreading globally in 2022, it became critical to evaluate whether residual immunity from smallpox vaccination provided cross-protection. To assess the cross-immune response to MPXV, we collected serum samples (n = 97) and PBMCs (n = 30) from healthy-donors, either born before 1974 and reporting smallpox vaccination during childhood or born after 1975 and not vaccinated with Vaccinia virus (VACV)-based vaccines. We evaluated the levels of anti-MPXV IgG and neutralizing antibodies (Nabs) and the presence of a T cell response against MPXV. We found anti-MPXV IgG and Nabs in 60 (89.6%) and 40 (70.1%) vaccinated individuals, respectively. We observed a T cell response to Orthopoxviruses and MPXV peptide pools in 30% of vaccinated individuals. We thus show that a high proportion of subjects who received the smallpox vaccine 40 to 60 years ago have humoral cross-immunity, while the T-cell-specific response against MPXV was observed in a smaller group (30%) of vaccinated individuals. This study, combined with information on immunity developed during natural infection or the administration of current vaccines, will contribute to a better understanding of humoral and cellular responses against MPXV.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
