{"doi":"10.1155/1992/26251","title":"Thymus Ontogeny in Frogs: T‐Cell Renewal atMetamorphosis","abstract":"<jats:p>Metamorphosis in amphibians presents a unique problem for the developing immune\nsystem. Because tadpoles are free‐living, they need an immune system to protect against\npotential pathogens. However, at metamorphosis, they acquire a variety of new adultspecific\nmolecules to which the tadpole immune system must become tolerant. We\nhypothesized that <jats:italic>Xenopus laevis</jats:italic> tadpoles may avoid potentially destructive antiself\nresponses by largely discarding the larval immune system at metamorphosis and\nacquiring a new one. By implanting triploid (3N) thymuses into diploid (2N) hosts, we\nexamined the influx and expansion of host T‐cell precursors in the donor thymus of\nnormally metamorphosing and metamorphosis‐inhibited frogs. We observed that donor\nthymocytes are replaced by host‐derived cells during metamorphosis, but inhibition of\nmetamorphosis does not prevent this exchange of cells. The implanted thymuses export\nT cells to the spleen. This donor‐derived pool of cells declines after metamorphosis in\nnormally developing frogs but is retained to a greater extent if metamorphosis is\ninhibited. These studies confirm previous observations of a metamorphosis‐associated\nwave of expansion of T cells and demonstrate that it is not dependent on the relatively\nhigh concentrations of thyroid hormones required for metamorphosis. Although some\nlarval T cells persist through metamorphosis, others may be destroyed or the larval\npopulation is significantly diluted by the expanding adult population.</jats:p>","journal":"Journal of Immunology Research","year":1992,"id":39812,"datarank":1.0251751009413335,"base_score":3.258096538021482,"endowment":3.258096538021482,"self_citation_contribution":0.4887144807032224,"citation_network_contribution":0.536460620238111,"self_endowment_contribution":0.4887144807032224,"citer_contribution":0.536460620238111,"corpus_percentile":null,"corpus_rank":null,"citation_count":25,"citer_count":15,"citers_with_citation_signal":14,"citers_with_endowment":14,"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":194651,"name":"Patrick J. Blair","orcid":null,"position":1,"is_corresponding":false},{"id":194652,"name":"A. Tray Davis","orcid":null,"position":2,"is_corresponding":false},{"id":194650,"name":"Louise A. Rollins-Smith","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"base_score":3.258096538021482,"endowment":3.258096538021482,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"1320967","pmcid":"PMC2275863","openalex_id":"https://openalex.org/W2078861830","authors":[],"funders":[{"funder_name":"National Science Foundation","grant_id":"DCB-8710235","title":null},{"funder_name":"National Science Foundation","grant_id":"DCB-9004666","title":null}],"total_grants":2,"fwci":0.2745,"citation_percentile":0.51644317,"influential_citations":0,"citation_trend":[{"year":2016,"count":1},{"year":2019,"count":1},{"year":2021,"count":2},{"year":2022,"count":4},{"year":2023,"count":2}],"oa_status":"gold","license":"cc-by","oa_locations":[{"url":"https://downloads.hindawi.com/journals/jir/1992/026251.pdf","host_type":"journal"},{"url":"https://downloads.hindawi.com/journals/jir/1992/026251.pdf","host_type":"publisher"},{"url":"http://downloads.hindawi.com/journals/jir/1992/026251.pdf","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/pdf/10.1155/1992/26251","host_type":"publisher"},{"url":"https://doi.org/10.1155/1992/26251","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/1320967","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/2275863","host_type":"repository"},{"url":"https://europepmc.org/articles/PMC2275863","host_type":"Europe_PMC"},{"url":"https://europepmc.org/articles/PMC2275863?pdf=render","host_type":"Europe_PMC"}],"fields_of_study":["T-cell and B-cell Immunology","Single-cell and spatial transcriptomics","Viral Infectious Diseases and Gene Expression in Insects","Animals","Cell Division","Cell Movement","Metamorphosis, Biological","Perchlorates","Ploidies","Sodium Compounds","Spleen","T-Lymphocytes","Thymus Gland","Xenopus laevis"],"mesh_terms":["Animals","Cell Division","Cell Movement","Metamorphosis, Biological","Perchlorates","Ploidies","Spleen","T-Lymphocytes","Thymus Gland","Xenopus laevis","Sodium Compounds"],"keywords":["Ontogeny","Biology","Genetics"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Life in Land"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-06-11T22:46:38.298608Z","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":[]}