{"doi":"10.4049/jimmunol.162.10.5695","title":"B Lymphocytes as Antigen-Presenting Cells for CD4+ T Cell Priming In Vivo","abstract":"<jats:title>Abstract</jats:title>\n                  <jats:p>The contribution of B lymphocytes as APCs for CD4+ T cell priming remains controversial, based on findings that B cells cannot provide the requisite ligating and costimulatory signals for naive T cells to be activated. In the current study, we have examined Ag-specific T:B cell collaboration under circumstances in which B cells take up Ag through Ig receptors in vivo. This results in their activation and an ability to effectively stimulate naive CD4+ T cells both in vitro and in vivo. The aim of this work was to establish some of the key molecular interactions, as well as kinetics, between Ag-specific T and B cells that enable this priming to take place. Our approach was to amplify the starting pools of both Ag-specific T and B cell populations in vivo to track directly the events during initial T:B cell collaborations. We show that the induction of optimal levels of T cell priming to a protein Ag requires the involvement of Ag-specific B cells. The interaction that results between Ag-specific T and B cells prevents the down-modulation of B7 costimulatory molecules usually observed in the absence of appropriate T cells. Moreover, this prevention in down-modulation is independent of CD40:CD40 ligand contact. Finally, we present data suggesting that once Ag-specific T and B cells interact, there is a rapid (1–2-h) down-regulation of antigenic complexes on the surface of the B lymphocytes, possibly to prevent them from engaging other T cells in the vicinity and therefore focus the initial interaction.</jats:p>","journal":"The Journal of Immunology","year":1999,"id":600684,"datarank":0.7962401546101808,"base_score":5.308267697401205,"endowment":5.308267697401205,"self_citation_contribution":0.7962401546101808,"citation_network_contribution":0.0,"self_endowment_contribution":0.7962401546101808,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":201,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1540039,"name":"Stephanie L Constant","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"B Lymphocytes as Antigen-Presenting Cells for CD4+ T Cell Priming In Vivo","abstract":"<jats:title>Abstract</jats:title>\n                  <jats:p>The contribution of B lymphocytes as APCs for CD4+ T cell priming remains controversial, based on findings that B cells cannot provide the requisite ligating and costimulatory signals for naive T cells to be activated. In the current study, we have examined Ag-specific T:B cell collaboration under circumstances in which B cells take up Ag through Ig receptors in vivo. This results in their activation and an ability to effectively stimulate naive CD4+ T cells both in vitro and in vivo. The aim of this work was to establish some of the key molecular interactions, as well as kinetics, between Ag-specific T and B cells that enable this priming to take place. Our approach was to amplify the starting pools of both Ag-specific T and B cell populations in vivo to track directly the events during initial T:B cell collaborations. We show that the induction of optimal levels of T cell priming to a protein Ag requires the involvement of Ag-specific B cells. The interaction that results between Ag-specific T and B cells prevents the down-modulation of B7 costimulatory molecules usually observed in the absence of appropriate T cells. Moreover, this prevention in down-modulation is independent of CD40:CD40 ligand contact. Finally, we present data suggesting that once Ag-specific T and B cells interact, there is a rapid (1–2-h) down-regulation of antigenic complexes on the surface of the B lymphocytes, possibly to prevent them from engaging other T cells in the vicinity and therefore focus the initial interaction.</jats:p>","is_dataset_classified":null,"base_score":5.308267697401205,"endowment":5.308267697401205,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"10229801","pmcid":null,"openalex_id":"https://openalex.org/W1598354195","authors":[],"funders":[{"funder_name":"NIAID NIH HHS","grant_id":"AI-39158","title":null}],"total_grants":1,"fwci":3.7732,"citation_percentile":0.9433269,"influential_citations":0,"citation_trend":[{"year":2012,"count":2},{"year":2013,"count":7},{"year":2014,"count":5},{"year":2015,"count":6},{"year":2016,"count":9},{"year":2017,"count":10},{"year":2018,"count":2},{"year":2019,"count":6},{"year":2020,"count":8},{"year":2021,"count":8},{"year":2022,"count":1},{"year":2023,"count":7},{"year":2024,"count":2},{"year":2025,"count":1}],"oa_status":"bronze","license":"https://academic.oup.com/pages/standard-publication-reuse-rights","oa_locations":[{"url":"https://journals.aai.org/jimmunol/article-pdf/162/10/5695/1099015/5695.pdf","host_type":"journal"},{"url":"https://journals.aai.org/jimmunol/article-pdf/162/10/5695/1099015/5695.pdf","host_type":"publisher"},{"url":"https://academic.oup.com/jimmunol/article-pdf/162/10/5695/62757112/5695.pdf","host_type":"publisher"},{"url":"https://doi.org/10.4049/jimmunol.162.10.5695","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/10229801","host_type":"repository"}],"fields_of_study":["T-cell and B-cell Immunology","Immunotherapy and Immune Responses","Immune Cell Function and Interaction"],"mesh_terms":["Animals","Antigen-Presenting Cells","B-Lymphocytes","Fluoresceins","Lymphocyte Activation","Membrane Glycoproteins","Mice, Transgenic","Muramidase","Receptors, Antigen, T-Cell","Receptors, Fc","Succinimides","Time Factors","CD4-Positive T-Lymphocytes","Up-Regulation","CD28 Antigens","B7-1 Antigen","CD40 Ligand","Mice"],"keywords":["Priming (agriculture)","CD40","Antigen-presenting cell","Cell biology","T cell","Antigen","In vivo","B cell","Biology","Streptamer","Cytotoxic T cell","In vitro","Immunology","Molecular biology","Immune system","Antibody","Biochemistry","Genetics"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Partnerships for the goals"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-07-29T13:50:38.815492Z","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":[]}