{"doi":"10.1101/2022.01.10.475620","title":"Strong SARS-CoV-2 N-specific CD8 <sup>+</sup> T immunity induced by engineered extracellular vesicles associates with protection from lethal infection in mice","abstract":"ABSTRACT SARS-CoV-2-specific CD8 + T cell immunity is expected to counteract viral variants in both efficient and durable ways. We recently described a way to induce a potent SARS-CoV-2 CD8 + T immune response through the generation of engineered extracellular vesicles (EVs) emerging from muscle cells. This method relies on intramuscular injection of DNA vectors expressing different SARS-CoV-2 antigens fused at their N-terminus with Nef mut protein, i.e., a very efficient EV-anchoring protein. However, quality, tissue distribution, and efficacy of these SARS-CoV-2-specific CD8 + T cells remained uninvestigated. To fill the gaps, antigen-specific CD8 + T lymphocytes induced by the immunization through the Nef mut -based method were characterized in terms of their polyfunctionality and localization at lung airways, i.e., the primary targets of SARS-CoV-2 infection. We found that injection of vectors expressing Nef mut /S1 and Nef mut /N generated polyfunctional CD8 + T lymphocytes in both spleens and bronchoalveolar lavage fluids (BALFs). When immunized mice were infected with 4.4 lethal doses 50% of SARS-CoV-2, all S1-immunized mice succumbed, whereas those developing the highest percentages of N-specific CD8 + T lymphocytes resisted the lethal challenge. We also provide evidence that the N-specific immunization coupled with the development of antigen-specific CD8 + T-resident memory cells in lungs, supporting the idea that the Nef mut - based immunization can confer a long-lasting, lung-specific immune memory. In view of the limitations of current anti-SARS-CoV-2 vaccines in terms of antibody waning and efficiency against variants, our CD8 + T cell-based platform could be considered for a new combination prophylactic strategy.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2022,"id":297849,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":7,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9534,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":370923,"name":"Chiara Chiozzini","orcid":"0000-0002-4153-0927","position":1,"is_corresponding":false},{"id":706241,"name":"Francesco Manfredi","orcid":"0000-0002-1746-1546","position":2,"is_corresponding":false},{"id":706242,"name":"Patrizia Leone","orcid":"0000-0002-5281-4917","position":3,"is_corresponding":false},{"id":986403,"name":"Massimo Spada","orcid":"0000-0003-0751-1893","position":4,"is_corresponding":false},{"id":412783,"name":"Antonio Di Virgilio","orcid":null,"position":5,"is_corresponding":false},{"id":706989,"name":"Andrea Giovannelli","orcid":null,"position":6,"is_corresponding":false},{"id":986404,"name":"Massimo Sanchez","orcid":"0000-0003-3696-7582","position":7,"is_corresponding":false},{"id":407465,"name":"Andrea Cara","orcid":"0000-0003-4967-1895","position":8,"is_corresponding":false},{"id":411718,"name":"Zuleika Michelini","orcid":"0000-0001-6841-7396","position":9,"is_corresponding":false},{"id":706243,"name":"Maurizio Federico","orcid":"0000-0003-4154-1025","position":10,"is_corresponding":false},{"id":706240,"name":"Flavia Ferrantelli","orcid":"0000-0002-0768-1078","position":0,"is_corresponding":true}],"reference_count":36,"raw_metadata":null,"created_at":"2026-07-19T00:31:31.270564Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}