Production and Immunogenicity of FeLV Gag-Based VLPs Exposing a Stabilized FeLV Envelope Glycoprotein

The envelope glycoprotein (Env) of retroviruses, such as the Feline leukemia virus (FeLV), is the main target of neutralizing humoral response, and therefore, a promising vaccine candidate, despite its reported poor immunogenicity. The incorporation of mutations that stabilize analogous proteins fro...

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Detalles Bibliográficos
Autores: Ortiz, Raquel|||0000-0002-6919-2026, Barajas Vélez, Ana|||0000-0003-1103-9499, Pons-Grífols, Anna|||0000-0002-8402-3941, Trinité, Benjamin|||0000-0003-3809-042X, Tarrés-Freixas, Ferran|||0000-0002-1569-0126, Rovirosa, Carla|||0000-0002-7111-0253, Urrea, Víctor|||0000-0002-2577-856X, Barreiro Vázquez, Antonio|||0000-0001-6095-5077, Gonzalez-Tendero, Anna, Rovira-Rigau, Maria, Cardona, Maria, Ferrer, Laura, Clotet Sala, Bonaventura|||0000-0003-3232-4598, Carrillo, Jorge|||0000-0003-0221-5948, Aguilar-Gurrieri, Carmen|||0000-0002-5701-7650, Blanco, Julià|||0000-0002-2225-0217
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:294992
Acceso en línea:https://ddd.uab.cat/record/294992
https://dx.doi.org/urn:doi:10.3390/v16060987
Access Level:acceso abierto
Palabra clave:Env
Vaccine
Virus-like particle (VLP)
FeLV
SOSIP
Veterinary science
Descripción
Sumario:The envelope glycoprotein (Env) of retroviruses, such as the Feline leukemia virus (FeLV), is the main target of neutralizing humoral response, and therefore, a promising vaccine candidate, despite its reported poor immunogenicity. The incorporation of mutations that stabilize analogous proteins from other viruses in their prefusion conformation (e.g., HIV Env, SARS-CoV-2 S, or RSV F glycoproteins) has improved their capability to induce neutralizing protective immune responses. Therefore, we have stabilized the FeLV Env protein following a strategy based on the incorporation of a disulfide bond and an Ile/Pro mutation (SOSIP) previously used to generate soluble HIV Env trimers. We have characterized this SOSIP-FeLV Env in its soluble form and as a transmembrane protein present at high density on the surface of FeLV Gag-based VLPs. Furthermore, we have tested its immunogenicity in DNA-immunization assays in C57BL/6 mice. Low anti-FeLV Env responses were detected in SOSIP-FeLV soluble protein-immunized animals; however, unexpectedly no responses were detected in the animals immunized with SOSIP-FeLV Gag-based VLPs. In contrast, high humoral response against FeLV Gag was observed in the animals immunized with control Gag VLPs lacking SOSIP-FeLV Env, while this response was significantly impaired when the VLPs incorporated SOSIP-FeLV Env. Our data suggest that FeLV Env can be stabilized as a soluble protein and can be expressed in high-density VLPs. However, when formulated as a DNA vaccine, SOSIP-FeLV Env remains poorly immunogenic, a limitation that must be overcome to develop an effective FeLV vaccine.