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Montes Berrueta, D.

Publications and source records attributed to Montes Berrueta, D..

3 recordsLinked to original sources

Predictive Modeling of Immune Escape and Antigenic Grouping of SARS-CoV-2 Variants

The ongoing adaptive evolution of SARS-CoV-2 is characterized by the continued emergence of novel variants that escape from previously acquired infection- and/or vaccination-derived immunity. This continued SARS-CoV-2 variant evolution has necessitated annual vaccine updates to better match circulating viral variants. To optimize protection against emerging variants of interest and concern, a reliable means of predicting the immune escape of novel variants is needed to enable at-risk preparation of new vaccines. Herein, we describe the development and applications of a risk calculator that uses statistical modeling to predict the immune escape of emerging variants. The calculator utilizes previously published spike-antibody epitope and escape profiles and in vitro neutralization assessment of a large panel of pseudotyped SARS-CoV-2 variants evaluated against clinical sera. The calculator enables the grouping of antigenically related SARS-CoV-2 variants to guide strain selection for at-risk vaccine design and preparation, in anticipation of potential future requests by the global public health agencies. Here, we demonstrated the strain selection exercises for the XBB.1.5- and JN.1/KP.2-adapted mRNA-1273 COVID-19 vaccines in the 2023-2024 and 2024-2025 seasons, respectively, which were supported by both the risk calculator and preclinical and clinical immunogenicity data and were later recommended by the global public health agencies.

immunology↗

mRNA-1273 vaccines adapted to JN.1 or KP.2 elicit cross-neutralizing responses against the JN.1 sublineages of SARS-CoV-2 in mice

The continued diversification of SARS-CoV-2 omicron lineage has given rise to the JN.1 variant and descendant strains (KP.2, KP.3, and XEC) that have prolonged the JN.1 infection wave. JN.1 and KP.2 show decreased susceptibility to neutralization sera in recipients of XBB.1.5 vaccine boosters, supporting the recent authorization of JN.1- and KP.2-matched mRNA vaccines in the United States, Europe, and other regions. We evaluated the immunogenicity of two updated monovalent variant-containing formulations of mRNA-1273 vaccines encoding the spike protein of the omicron subvariants JN.1 (mRNA-1273.167) and KP.2 (mRNA-1273.712) as compared with the monovalent XBB.1.5 vaccine (mRNA-1273.815). The vaccines were administered either as a two-dose primary series in naive mice or as a booster (third) dose in mice previously immunized with two-dose primary series of mRNA-1273 (ancestral strain). The neutralizing antibody response elicited by these vaccines against JN.1 subvariants (KP.3 and LA.2) and the recombinant strain (XEC), which achieved dominance in the United States during late 2024, was evaluated. Primary series immunization with either JN.1- or KP.2-matched vaccine elicited robust neutralizing antibody titers against the matched strains and effectively cross-neutralized KP.3, LA.2, and XEC, but not the antigenically distant XBB.1.5. Similarly, JN.1- and KP.2-matched vaccines administered as a booster (third) dose increased titers against the corresponding strains and JN.1-related subvariants, but not against XBB.1.5. These data suggest these strains are antigenically similar with relatively few spike differences between JN.1 and KP.2/JN.1-related subvariants. Our results demonstrate the potency of JN.1- and KP.2-containing mRNA-1273 vaccines in neutralizing the matched variants and their utility in cross-neutralizing JN.1-related subvariants KP.3, LA.2, and XEC. Taken together, these data suggest that the licensed JN.1 and KP.2 mRNA vaccines are likely to continue to protect against the emerging strains as the JN.1 lineage further evolves.

immunology↗

Development of SARS-CoV-2 mRNA vaccines encoding spike N-terminal and receptor binding domains

With the success of mRNA vaccines against coronavirus disease 2019 (COVID-19), strategies can now focus on improving vaccine potency, breadth, and stability. We present the design and preclinical evaluation of domain-based mRNA vaccines encoding the wild-type spike-protein receptor-binding (RBD) and/or N-terminal domains (NTD). An NTD-RBD linked candidate vaccine, mRNA-1283, showed improved antigen expression, antibody responses, and stability at refrigerated temperatures (2-8{degrees}C) compared with the clinically available mRNA-1273, which encodes the full-length spike protein. In mice administered mRNA-1283 as a primary series, booster, or variant-specific booster, similar or greater immune responses and protection from viral challenge were observed against wild-type, beta, delta, or omicron (BA. 1) compared with mRNA-1273 immunized mice, especially at lower vaccine dosages. These results support clinical assessment of mRNA-1283 (NCT05137236). One Sentence SummaryA domain-based mRNA vaccine, mRNA-1283, is immunogenic and protective against SARS-CoV-2 and emerging variants in mice.

immunology↗