{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T14:14:55Z","timestamp":1788963295249,"version":"build-2803163510"},"reference-count":58,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T00:00:00Z","timestamp":1788912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:p>\n                    Feline obesity is common, and in other species it has been linked to immune dysregulation; yet its immunological consequences in cats, and their modulation by age and sex, remain poorly defined. Whole blood from 78 neutered client-owned cats (37 males, 41 females; 1\u201316 years) was analyzed by flow cytometry using a panel characterizing T cells (including CD5\n                    <jats:sup>+<\/jats:sup>\n                    CD4\n                    <jats:sup>+<\/jats:sup>\n                    and CD5\n                    <jats:sup>+<\/jats:sup>\n                    CD8\n                    <jats:sup>+<\/jats:sup>\n                    subsets), B cells (CD21\n                    <jats:sup>+<\/jats:sup>\n                    ) and natural killer (CD56\n                    <jats:sup>+<\/jats:sup>\n                    ) cells with their activation (CD80) and proliferation (Ki67) status. Cats were grouped by body condition score into normal-weight (4\u20135) and overweight (6\u20139); lymphocyte proliferation was assessed in a subset by a carboxyfluorescein succinimidyl ester assay after concanavalin A stimulation, and serum amyloid A, triglycerides and adiponectin were measured in overweight cats. Across the cohort, overweight cats displayed higher frequencies of proliferating CD21\n                    <jats:sup>+<\/jats:sup>\n                    Ki67\n                    <jats:sup>+<\/jats:sup>\n                    B cells than normal-weight cats, while the proliferation assay was descriptively consistent with enhanced T-cell proliferation in both sexes. Increasing age was associated with a decline in CD5\n                    <jats:sup>+<\/jats:sup>\n                    CD4\n                    <jats:sup>+<\/jats:sup>\n                    T cells in both sexes and, in females, additionally in CD5\n                    <jats:sup>+<\/jats:sup>\n                    CD21\n                    <jats:sup>+<\/jats:sup>\n                    cells alongside rising CD80 expression. Sex differences shifted across life, from B-cell activation in young adults to T-cell subsets in adults (higher CD5\n                    <jats:sup>+<\/jats:sup>\n                    CD8\n                    <jats:sup>+<\/jats:sup>\n                    in males, higher Ki67\n                    <jats:sup>+<\/jats:sup>\n                    fractions in females) and CD56\n                    <jats:sup>+<\/jats:sup>\n                    NK cells in the oldest cats. Body-condition effects were largely age- and sex-specific and emerged only after stratification: adult overweight males showed higher proliferating CD4\n                    <jats:sup>+<\/jats:sup>\n                    Ki67\n                    <jats:sup>+<\/jats:sup>\n                    and CD8\n                    <jats:sup>+<\/jats:sup>\n                    Ki67\n                    <jats:sup>+<\/jats:sup>\n                    T cells, young-adult overweight females higher CD5\n                    <jats:sup>+<\/jats:sup>\n                    and activated CD5\n                    <jats:sup>+<\/jats:sup>\n                    CD21\n                    <jats:sup>+<\/jats:sup>\n                    CD80\n                    <jats:sup>+<\/jats:sup>\n                    cells, and aged overweight females fewer proliferating CD5\n                    <jats:sup>+<\/jats:sup>\n                    CD21\n                    <jats:sup>+<\/jats:sup>\n                    Ki67\n                    <jats:sup>+<\/jats:sup>\n                    B cells. Among overweight cats, higher adiponectin was associated with fewer CD5\n                    <jats:sup>+<\/jats:sup>\n                    lymphocytes, with no associations for serum amyloid A or triglycerides. Overall, feline obesity was associated with subtle changes in immune-cell composition but more pronounced effects on lymphocyte proliferative responsiveness, both strongly modulated by age and sex.\n                  <\/jats:p>","DOI":"10.3389\/fvets.2026.1943507","type":"journal-article","created":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T13:48:40Z","timestamp":1788961720000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Body condition, age, and sex as modulators of peripheral blood immune-cell populations and lymphocyte proliferation in cats"],"prefix":"10.3389","volume":"13","author":[{"given":"Hanna","family":"Kr\u00fcger","sequence":"first","affiliation":[{"name":"Institute of Veterinary Medicine, Georg-August University G\u00f6ttingen","place":["G\u00f6ttingen, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Moritz","sequence":"additional","affiliation":[{"name":"Clinic of Small Animals-Internal Medicine, Faculty of Veterinary Medicine, Justus-Liebig-University Giessen","place":["Giessen, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Berit","family":"Roshani","sequence":"additional","affiliation":[{"name":"Unit of Infection Models, German Primate Centre, Leibniz-Institute for Primate Research G\u00f6ttingen","place":["G\u00f6ttingen, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephan","family":"Neumann","sequence":"additional","affiliation":[{"name":"Institute of Veterinary Medicine, Georg-August University G\u00f6ttingen","place":["G\u00f6ttingen, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,9]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1940S","DOI":"10.1093\/jn\/136.7.1940S","article-title":"The growing problem of obesity in dogs and cats","volume":"136","author":"German","year":"2006","journal-title":"J Nut."},{"key":"B2","doi-asserted-by":"publisher","first-page":"91","DOI":"10.1053\/jfms.2000.0078","article-title":"How fat is the cat?","volume":"2","author":"Butterwick","year":"2000","journal-title":"J Feline Med Surg."},{"key":"B3","unstructured":"European\n              Pet Food Industry Federation (FEDIAF)\n            \n          \n          Statistics."},{"key":"B4","doi-asserted-by":"publisher","first-page":"295","DOI":"10.17221\/145\/2015-VETMED","article-title":"Feline obesity - prevalence, risk factors, pathogenesis, associated conditions and assessment: a review","volume":"61","author":"Tarkosova","year":"2016","journal-title":"Vet Med."},{"key":"B5","first-page":"4","article-title":"Prevalence and risk factors for obesity in adult cats from private US veterinary practices","volume":"3","author":"Lund","year":"2005","journal-title":"Int J Appl Res Vet Med."},{"key":"B6","doi-asserted-by":"publisher","first-page":"235","DOI":"10.1016\/j.prevetmed.2024.106398","article-title":"Overweight and obese body condition in ~ 4. 9 million dogs and ~ 1. 3 million cats seen at primary practices across the USA : Prevalences by life stage from early growth to senior","author":"Montoya","year":"2025","journal-title":"Prev Vet Med."},{"key":"B7","doi-asserted-by":"publisher","first-page":"25","DOI":"10.1177\/1098612X231155016","article-title":"Commonly diagnosed disorders in domestic cats in the UK and their associations with sex and age","author":"Neill","year":"2023","journal-title":"J Feline Med Surg."},{"key":"B8","doi-asserted-by":"publisher","first-page":"1110","DOI":"10.1177\/1098612X17752198","article-title":"Strong associations of nine-point body condition scoring with survival and lifespan in cats","volume":"20","author":"Teng","year":"2018","journal-title":"J Feline Med Surg."},{"key":"B9","doi-asserted-by":"publisher","first-page":"603","DOI":"10.1111\/jsap.12905","article-title":"Associations of body condition score with health conditions related to overweight and obesity in cats","volume":"59","author":"Teng","year":"2018","journal-title":"J Small Anim Pract."},{"key":"B10","doi-asserted-by":"publisher","first-page":"20","DOI":"10.1186\/s12917-024-04011-0","article-title":"The effect of obesity and subsequent weight reduction on cardiac morphology and function in cats","author":"Partington","year":"2024","journal-title":"BMC Vet Res."},{"key":"B11","doi-asserted-by":"publisher","first-page":"25","DOI":"10.1111\/imr.13354","article-title":"T cells in obesity- associated inflammation : the devil is in the details","volume":"324","author":"Valentine","year":"2024","journal-title":"Immunol Rev."},{"key":"B12","doi-asserted-by":"publisher","first-page":"914","DOI":"10.1038\/nm.1964","article-title":"CD8 + effector T cells contribute to macrophage recruitment and adipose tissue inflammation in obesity","volume":"15","author":"Nishimura","year":"2009","journal-title":"Nat Med."},{"key":"B13","doi-asserted-by":"publisher","first-page":"921","DOI":"10.1038\/nm.2001","article-title":"Normalization of obesity-associated insulin resistance through immunotherapy","volume":"15","author":"Winer","year":"2009","journal-title":"Nat Publ Gr."},{"key":"B14","doi-asserted-by":"publisher","first-page":"1839","DOI":"10.3390\/ijms22041839","article-title":"Cells with a senescent-associated secretory phenotype accumulate in the adipose tissue of individuals with obesity","volume":"22","author":"Frasca","year":"2021","journal-title":"Int J Mol Sci."},{"key":"B15","doi-asserted-by":"publisher","first-page":"263","DOI":"10.1093\/cei\/uxac079","article-title":"Review B cell contribution to immunometabolic dysfunction and impaired immune responses in obesity","volume":"210","author":"Oleinika","year":"2022","journal-title":"Clin Exp Immunol."},{"key":"B16","doi-asserted-by":"publisher","first-page":"25555","DOI":"10.3389\/fimmu.2019.02555","article-title":"Adiponectin limits IFN- \u03b3 and IL-17 producing CD4 T cells in obesity by restraining cell intrinsic glycolysis","volume":"10","author":"Surendar","year":"2019","journal-title":"Front Immunol."},{"key":"B17","doi-asserted-by":"publisher","first-page":"2323","DOI":"10.1002\/eji.201041349","article-title":"Adiponectin is a negative regulator of antigen-activated T cells","volume":"41","author":"Wilk","year":"2011","journal-title":"Eur J Immunol."},{"key":"B18","doi-asserted-by":"publisher","first-page":"1","DOI":"10.3389\/fvets.2019.00284","article-title":"Diagnostic criteria for obesity disease in cats","volume":"6","author":"Okada","year":"2019","journal-title":"Front Vet Sci."},{"key":"B19","doi-asserted-by":"publisher","first-page":"567","DOI":"10.2460\/ajvr.2001.62.567","article-title":"Evaluation of a nonradioactive colorimetric assay for analysis of lymphocyte proliferation in healthy cats","volume":"62","author":"Saker","year":"2001","journal-title":"Am J Vet Res."},{"key":"B20","doi-asserted-by":"publisher","first-page":"146","DOI":"10.1016\/j.vetimm.2007.10.015","article-title":"The effects of obesity and fatty acids on the feline immune system","volume":"122","author":"Jaso-Friedmann","year":"2008","journal-title":"Vet Immunol Immunopathol."},{"key":"B21","doi-asserted-by":"publisher","first-page":"73","DOI":"10.1016\/j.vetimm.2004.03.002","article-title":"Age-related differences in parameters of feline immune status","volume":"100","author":"Campbell","year":"2004","journal-title":"Vet Immunol Immunopathol."},{"key":"B22","doi-asserted-by":"publisher","first-page":"S60","DOI":"10.1016\/j.jcpa.2009.10.011","article-title":"Aging, Immunosenescence and inflammageing in the dog and cat","volume":"142","author":"Day","year":"2010","journal-title":"J Comp Pathol."},{"key":"B23","doi-asserted-by":"publisher","first-page":"4","DOI":"10.1093\/gerona\/glu057","article-title":"Chronic inflammation (inflammaging) and its potential contribution to age-associated diseases","volume":"69","author":"Franceschi","year":"2014","journal-title":"J Gerontol."},{"key":"B24","doi-asserted-by":"publisher","first-page":"e70159","DOI":"10.1111\/jvim.70159","article-title":"Immunosenescence and inflammaging in dogs and cats : a narrative review","volume":"39","author":"Mckenzie","year":"2025","journal-title":"J Vet Intern Med."},{"key":"B25","doi-asserted-by":"publisher","first-page":"626","DOI":"10.1038\/nri.2016.90","article-title":"Sex differences in immune responses","volume":"16","author":"Klein","year":"2016","journal-title":"Nat Publ Gr."},{"key":"B26","doi-asserted-by":"publisher","first-page":"487","DOI":"10.1038\/s41577-024-00996-9","article-title":"The conneXion between sex and immune responses","volume":"24","author":"Forsyth","year":"2024","journal-title":"Nat Rev Immunol."},{"key":"B27","doi-asserted-by":"publisher","first-page":"883","DOI":"10.1093\/gerona\/glab330","article-title":"Age-related sexual dimorphism on the longitudinal progression of blood immune cells in BALB \/ cByJ Mice","volume":"77","author":"Serre-Miranda","year":"2022","journal-title":"Biol Sci Med Sci."},{"key":"B28","first-page":"13","article-title":"Development and validation of a body condition score system for cats: a clinical tool","volume":"25","author":"Laflamme","year":"1997","journal-title":"Feline Pract."},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.3389\/fvets.2026.1778256","article-title":"Flow cytometric evaluation of monoclonal antibodies for cross-reactivity with feline leukocytes","author":"Kr\u00fcger","year":"2026","journal-title":"Front Vet Sci."},{"key":"B30","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1093\/biomet\/93.3.491","article-title":"Adaptive linear step-up procedures that control the false discovery rate","volume":"93","author":"Benjamini","year":"2006","journal-title":"Biometrika."},{"key":"B31","doi-asserted-by":"publisher","first-page":"175","DOI":"10.3758\/BF03193146","article-title":"G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences","volume":"39","author":"Faul","year":"2007","journal-title":"Behav Reserach Methods."},{"key":"B32","doi-asserted-by":"publisher","first-page":"1","DOI":"10.3389\/fimmu.2021.616650","article-title":"Phenotypic and functional characterization of double negative b cells in the blood of individuals with obesity","volume":"12","author":"Frasca","year":"2021","journal-title":"Front Immunol."},{"key":"B33","doi-asserted-by":"publisher","first-page":"81","DOI":"10.1016\/j.jim.2007.09.015","article-title":"In vivo depletion of CD4+CD25+ regulatory T cells in cats","volume":"329","author":"Smithberg","year":"2008","journal-title":"J Immunol Methods."},{"key":"B34","doi-asserted-by":"publisher","first-page":"92","DOI":"10.1016\/j.mad.2006.11.016","article-title":"Inflammaging and anti-inflammaging : a systemic perspective on aging and longevity emerged from studies in humans","volume":"128","author":"Franceschi","year":"2007","journal-title":"Mech Ageing Dev."},{"key":"B35","doi-asserted-by":"publisher","first-page":"101755","DOI":"10.1016\/j.molmet.2023.101755","article-title":"Chronic inflammation and the hallmarks of aging","volume":"74","author":"Baechle","year":"2023","journal-title":"Mol Metab."},{"key":"B36","doi-asserted-by":"publisher","first-page":"543","DOI":"10.1002\/cyto.a.22855","article-title":"Age and gender leucocytes variances and references values generated using the standardized ONE-study protocol","volume":"89","author":"Kverneland","year":"2016","journal-title":"Cytom Part A."},{"key":"B37","doi-asserted-by":"publisher","first-page":"e20221346","DOI":"10.1084\/jem.20221346","article-title":"Age-associated B cells are heterogeneous and dynamic drivers of autoimmunity in mice","volume":"220","author":"Nickerson","year":"2023","journal-title":"J Exp Med."},{"key":"B38","doi-asserted-by":"publisher","first-page":"330","DOI":"10.1016\/j.arr.2010.08.004","article-title":"Age effects on B cells and humoral immunity in humans","volume":"10","author":"Frasca","year":"2011","journal-title":"Ageing Res Rev."},{"key":"B39","doi-asserted-by":"publisher","first-page":"1625","DOI":"10.1172\/JCI14873","article-title":"Estrogen alters thresholds for B cell apoptosis and activation","volume":"109","author":"Grimaldi","year":"2002","journal-title":"J Clin Invest."},{"key":"B40","doi-asserted-by":"publisher","first-page":"1385501","DOI":"10.3389\/fimmu.2024.1385501","article-title":"Hormones and B-cell development in health and autoimmunity","volume":"15","author":"Santana-S\u00e1nchez","year":"2024","journal-title":"Front Immunol."},{"key":"B41","doi-asserted-by":"publisher","first-page":"780","DOI":"10.1038\/s41590-023-01463-8","article-title":"The X-linked epigenetic regulator UTX controls NK cell-intrinsic sex differences","volume":"24","author":"Cheng","year":"2026","journal-title":"Nat Immunol."},{"key":"B42","doi-asserted-by":"publisher","first-page":"25","DOI":"10.1016\/j.mad.2016.04.001","article-title":"The effect of sex on immune cells in healthy aging : elderly women have more robust natural killer lymphocytes than do elderly men","volume":"156","author":"Al-attar","year":"2016","journal-title":"Mech Ageing Dev."},{"key":"B43","doi-asserted-by":"publisher","first-page":"270","DOI":"10.1002\/cyto.b.21234","article-title":"Reference intervals for leukocyte subsets in adults: results from a population-based study using 10-color flow cytometry","volume":"88","author":"Melzer","year":"2015","journal-title":"Clin Cytom."},{"key":"B44","doi-asserted-by":"publisher","first-page":"401","DOI":"10.2337\/db11-1065","article-title":"Morbidly obese human subjects have increased peripheral blood CD4 + T cells with skewing toward a treg- and Th2-dominated phenotype","volume":"61","author":"Van der Weerd","year":"2012","journal-title":"Diabetes."},{"key":"B45","doi-asserted-by":"publisher","first-page":"1523","DOI":"10.3390\/medicina60091523","article-title":"Characterizing human peripheral blood lymphocyte phenotypes and their correlations with body composition in normal-weight, overweight, and obese healthy young adults","volume":"60","author":"Kosovski","year":"2024","journal-title":"Medicina."},{"key":"B46","doi-asserted-by":"publisher","first-page":"1110","DOI":"10.1161\/ATVBAHA.119.312467","article-title":"B lymphocytes and adipose tissue inflammation","volume":"40","author":"Srikakulapu","year":"2020","journal-title":"Arterioscler Thromb Vasc Biol."},{"key":"B47","doi-asserted-by":"publisher","first-page":"2762","DOI":"10.2337\/db12-1404","article-title":"Adipose tissue macrophages function as antigen-presenting cells and regulate adipose tissue CD4 + T cells in mice","volume":"62","author":"Morris","year":"2013","journal-title":"Diabetes."},{"key":"B48","doi-asserted-by":"publisher","first-page":"8666","DOI":"10.3390\/ijms22168666","article-title":"Adipose tissue dendritic cells: critical regulators of obesity-induced inflammation and insulin resistance","volume":"22","author":"Soedono","year":"2021","journal-title":"Int J Mol Sci."},{"key":"B49","doi-asserted-by":"publisher","first-page":"91","DOI":"10.1016\/j.mad.2017.01.004","article-title":"Obesity induces pro-inflammatory B cells and impairs B cell function in old mice","volume":"162","author":"Frasca","year":"2017","journal-title":"Mech Ageing Dev."},{"key":"B50","doi-asserted-by":"publisher","first-page":"1121","DOI":"10.1016\/j.cmet.2022.07.002","article-title":"T-bet + B cells accumulate in adipose tissue and exacerbate metabolic disorder during obesity","volume":"34","author":"H\u00e4ggl\u00f6f","year":"2022","journal-title":"Cell Metab."},{"key":"B51","doi-asserted-by":"publisher","first-page":"2637","DOI":"10.1161\/ATVBAHA.114.304636","article-title":"T-cell profile in adipose tissue is associated with insulin resistance and systemic inflammation in humans","volume":"34","author":"Mclaughlin","year":"2014","journal-title":"Arterioscler Thromb Vasc Biol."},{"key":"B52","doi-asserted-by":"publisher","first-page":"219","DOI":"10.3390\/biom14020219","article-title":"Bariatric surgery induces alterations in the immune profile of peripheral blood T cells","volume":"14","author":"Barbosa","year":"2024","journal-title":"Biomolecules."},{"key":"B53","doi-asserted-by":"publisher","first-page":"35","DOI":"10.1186\/s12979-023-00361-9","article-title":"Obesity accelerates age defects in B cells, and weight loss improves B cell function","volume":"20","author":"Frasca","year":"2023","journal-title":"Immun Ageing."},{"key":"B54","doi-asserted-by":"publisher","first-page":"2060","DOI":"10.3389\/fimmu.2020.02060","article-title":"Obesity accelerates age defects in mouse and human B cells","volume":"11","author":"Frasca","year":"2020","journal-title":"Front Immunol."},{"key":"B55","doi-asserted-by":"publisher","first-page":"1","DOI":"10.3389\/fendo.2022.917402","article-title":"Changes of peripheral Th17 cells subset in overweight and obese children after body weight reduction","volume":"13","author":"Artemniak-Wojtowicz","year":"2022","journal-title":"Front Endocrinol."},{"key":"B56","doi-asserted-by":"publisher","first-page":"1044737","DOI":"10.3389\/fimmu.2022.1044737","article-title":"Drastic transformation of visceral adipose tissue and peripheral CD4 T cells in obesity","volume":"13","author":"Shirakawa","year":"2023","journal-title":"Front Immunol."},{"key":"B57","doi-asserted-by":"publisher","first-page":"2319","DOI":"10.1007\/s00125-012-2598-x","article-title":"Adiponectin : mechanistic insights and clinical implications","volume":"55","author":"Turer","year":"2012","journal-title":"Diabetologica."},{"key":"B58","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1210\/endrev\/bnaa004","article-title":"Metabolically healthy obesity","volume":"41","author":"Bl\u00fcher","year":"2020","journal-title":"Endocr Rev."}],"container-title":["Frontiers in Veterinary Science"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fvets.2026.1943507\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T13:48:44Z","timestamp":1788961724000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fvets.2026.1943507\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,9]]},"references-count":58,"alternative-id":["10.3389\/fvets.2026.1943507"],"URL":"https:\/\/doi.org\/10.3389\/fvets.2026.1943507","relation":{},"ISSN":["2297-1769"],"issn-type":[{"value":"2297-1769","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,9]]},"article-number":"1943507"}}