Immunogenicity of monkeypox virus surface proteins and cross-reactive antibody responses in vaccinated and infected individuals: implications for vaccine and therapeutic developmentLiu, Wang, Zhang
et alInfect Dis Poverty (2025) 14 (1), 12
Abstract: The monkeypox virus (MPXV) has raised global health concerns due to its widespread transmission. This study evaluated the MPXV immunogenic antigens and the impact of vaccinia virus (VACV) vaccination and MPXV infection on cross-reactive antibody responses to conserved proteins from representative MPXV strains that reflected the evolutionary trajectory.Phylogenetic analyses were first conducted to reveal the evolutionary trajectory of MPXV from 1970 to 2024. A total of 84 serum samples were collected: 42 from VACV-vaccinated individuals, 12 from MPXV-infected participants in the early stage, 13 from the late stage, and 17 from naive individuals. Demographic data, MPXV and HIV status, as well as other clinical information were collected using standardized forms. Immunogenicity, cross-reactive antibody responses, and amino acid similarity to 15 MPXV surface proteins were assessed using enzyme-linked immunosorbent assays, VACV neutralization tests, and sequence alignment. Data analysis methods included analysis of variance, Mann-Whitney U test, binary logistic regression, Pearson correlation, and linear regression, with a significance threshold of P < 0.05.The 186 complete genome sequences were classified into different clades and lineages, ranging from clade Ia to clade IIb C.1.1. Individuals infected with MPXV demonstrated strong antibody responses to antigens A35R, B6R, H3L, and E8L. VACV-vaccinated individuals exhibited broader cross-reactivity, particularly against A21L (P = 0.0003), A28L (P = 0.0028), A29L (P = 0.0324), G2R (P = 0.0003), and H2R (P = 0.0008), compared to MPXV-infected individuals. Pearson correlation analysis revealed significant associations (P = 0.0049) between antibody responses and the amino acid sequence similarity with other orthopoxviruses. Furthermore, MPXV-infected individuals exhibited greater neutralizing activity against VACV than those VACV-vaccinated individuals (P < 0.0001), while the vaccinated group retained cross-protective immunity even decades post-vaccination.A35R, B6R, H3L, and E8L are the main immunogenic antigens of MPXV. VACV-vaccination triggers a cross-reactive antibody response to MPXV surface proteins. Our findings suggest the need for targeted vaccines and antibody treatments for MPXV, as well as the reintroduction of smallpox vaccinations with booster doses for high-risk groups.© 2025. The Author(s).
A penta-component mpox mRNA vaccine induces protective immunity in nonhuman primatesYe, Zhang, Zhang
et alNat Commun (2024) 15 (1), 10611
Abstract: The recent worldwide outbreaks of mpox prioritize the development of a safe and effective mRNA vaccine. The contemporary mpox virus (MPXV) exhibits changing virological and epidemiological features, notably affecting populations already vulnerable to human immunodeficiency virus (HIV). Herein, we profile the immunogenicity of AR-MPXV5, a penta-component mRNA vaccine targeting five specific proteins (M1R, E8L, A29L, A35R, and B6R) from the representative contemporary MPXV clade II strain, in both naive and simian immunodeficiency virus (SIV)-infected nonhuman primates. Immunization with two doses of AR-MPXV5 to cynomolgus macaques effectively elicits antibody responses and cellular responses. Importantly, based on the challenge model with a contemporary MPXV clade II strain, AR-MPXV5 demonstrates effective efficacy in preventing skin lesions, eliminating viremia and reducing viral loads in multiple tissues after challenge in naive male animals. More importantly, AR-MPXV5 is well-tolerated in stable chronic SIV-infected rhesus monkeys, while eliciting comparable MPXV-specific humoral and cellular responses in both naive and SIV-infected monkeys. Together, these results support further clinical development of the AR-MPXV5 vaccine.© 2024. The Author(s).
Computational identification of monkeypox virus epitopes to generate a novel vaccine antigen against MpoxDülek, Mutlu, Koçkaya
et alBiologicals (2024) 88, 101798
Abstract: Monkeypox virus (MPXV) belonging to poxviridae family causes chronic viral disease in various mammals including human and monkeys. Conventional vaccines developed against smallpox of poxviridae, are not specific against Mpox. Also, they can cause various side effects after vaccination. In this study, we aimed to analyze the A17L, A28L, A37R, A43R, E8L, H3L, B6R, and M1R structural proteins of MPXV and identify epitopes in them which can be used to generate vaccine antigens. Among the proteins analyzed, the M1R protein was predicted to be more appropriate for use in vaccine research due to its high antigenicity value and other physicochemical features. Also, A17L, B6R and E8L had high antigenicity values. E8L protein was more conserved while the A37R, A43R, and B6R proteins had signal peptides. Although a total of eight B cell epitopes were predicted in all proteins analyzed, CNGETK epitope belonging to B6R protein had the highest antigenicity value (1.7083), as well as was non-allergenic, non-toxic, and soluble. Based on T cell epitope analyses performed on all proteins, fourteen MHC-I/II epitopes were predicted that are antigenic, non-allergenic and non-toxic, as well as soluble. Among them, MHC-I related-HEIYDRNVGF epitope in A28L protein had the highest antigenicity value (1.6650) and MHC-II related-IGNIKIVQIDIRDIK epitope in A37R protein had the highest antigenicity value (2.0280). In conclusion, eight structural proteins of MPXV were successfully analyzed and 22 important epitopes were identified that could serve as vaccine antigens or in serological studies to develop diagnostic tools.Copyright © 2024 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.
Mpox global health emergency: Insights into the virus, immune responses, and advancements in vaccines PART II: Insights into the advancements in vaccinesPrompetchara, Ketloy, Khawsang
et alAsian Pac J Allergy Immunol (2024) 42 (3), 191-206
Abstract: Mpox is currently a global health emergency. This review (Part II) aims to provide insights into Mpox vaccines and their advancements, offering easily digestible information for healthcare workers and researchers. Current Mpox vaccines are all live-attenuated, previously approved for smallpox, and are classified into non-replicating (Modified Vaccinia Ankara-Bavarian Nordic or MVA-BN) and replicating vaccines (Lister clone16m8 KM Biologic or LC16m8KMB and Acambis2000 or ACAM2000). Replicating vaccines offer long-lasting immunity but are contraindicated for immunocompromised individuals and those with extensive dermatitis. Replicating vaccines are administered as a single dose via epicutaneous scarification, while the non-replicating vaccine is given as two subcutaneous doses. Regulatory approvals in various countries are based on animal challenge studies, with limited effectiveness data available. Only LC16m8 is approved for children in Japan, while the others are approved for individuals aged 18 and older. Clinical trials are currently investigating the efficacy and safety of MVA-BN, particularly in children and for post-exposure prophylaxis (PEP). Novel Mpox vaccines that provide cross-protection against orthopoxviruses are needed, with DNA, subunit, and mRNA platforms under development. MPXV-neutralizing antibody-inducing target antigens for vaccine development include the outer envelope antigens of extracellular enveloped virus (EEV): A35R and B6R, and the inner membrane antigens of intracellular mature virus (IMV): M1R, A29L, H3L, and E8L. Two mRNA vaccines are currently in early clinical stages. Importantly, the COVID-19 pandemic underscored the importance of addressing vaccine disparities and improving global access. Transformative approaches are being explored to overcome this challenge and to enhance access in low- and middle-income countries.