{"doi":"10.1371/journal.pntd.0010882","title":"Expansion of CD8+ T cell population in Lassa virus survivors with low T cell precursor frequency reveals durable immune response in most survivors","abstract":"INTRODUCTION: Lassa virus is a priority pathogen for vaccine research and development, however the duration of cellular immunity and protection in Lassa fever (LF) survivors remains unclear. METHODS: We investigated Lassa virus specific CD8+ T cell responses in 93 LF survivors. Peripheral blood mononuclear cells from these individuals were infected with recombinant vesicular stomatitis virus encoding Lassa virus antigens and virus specific T cell responses were measured after 18-hour incubation. Participants who had undetectable CD8+ T cell response underwent further analysis using a 10-day T cell proliferation assays to evaluate for low T cell precursor frequency. RESULTS: Forty-five of the 93 LF survivors did not have a Lassa virus specific CD8+ T cell response. Of those with responses and a known date of onset of LF (N = 11), 9 had LF within the last ten years. Most participants without a measurable CD8+ T cell response were more than 10 years removed from a clinical history of LF (N = 14/16). Fourteen of 21 patients (67%) with undetectable CD8+ T cell response had a measurable Lassa virus specific CD8+ T cell response with the 10-day assay. DISCUSSION: Despite reports of strong CD8+ T cell responses during acute Lassa virus infection, circulating Lassa virus-specific CD8+ T cells declined to undetectable levels in most Lassa fever survivors after ten years when evaluated with an 18-hour T cell stimulation. However, when Lassa virus-specific T cells were expanded prior to restimulation, a Lassa virus-specific CD8+ T cell response could be detected in many if the samples that were negative in the 18-hour stimulation assay, suggesting that prolonged cellular immunity does exist in Lassa fever survivors at low frequencies.","journal":"PLoS neglected tropical diseases","year":2022,"id":260441,"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":16,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9605,"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":362008,"name":"Saori Sakabe","orcid":"0000-0002-1619-8678","position":1,"is_corresponding":false},{"id":251089,"name":"Mambu Momoh","orcid":"0000-0001-7091-1027","position":2,"is_corresponding":false},{"id":62139,"name":"Lansana Kanneh","orcid":null,"position":3,"is_corresponding":false},{"id":360924,"name":"Nell G. Bond","orcid":"0000-0002-4996-4025","position":4,"is_corresponding":false},{"id":62204,"name":"Robert F. Garry","orcid":"0000-0002-5683-3250","position":5,"is_corresponding":false},{"id":251097,"name":"Donald S. Grant","orcid":"0000-0002-4329-0795","position":6,"is_corresponding":false},{"id":227994,"name":"Juan Carlos de la Torre","orcid":"0000-0002-8171-8115","position":7,"is_corresponding":false},{"id":362009,"name":"Michael B. A. Oldstone","orcid":"0000-0003-0804-0501","position":8,"is_corresponding":false},{"id":62205,"name":"John S. Schieffelin","orcid":"0000-0001-6642-5739","position":9,"is_corresponding":false},{"id":251093,"name":"Brian M. Sullivan","orcid":"0000-0003-4277-6037","position":10,"is_corresponding":false},{"id":362007,"name":"Stephanie M. LaVergne","orcid":"0000-0001-5902-1154","position":0,"is_corresponding":true}],"reference_count":37,"raw_metadata":null,"created_at":"2026-07-19T00:26:07.666421Z","pmid":"36441765","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":[]}