{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T05:16:21Z","timestamp":1783055781838,"version":"3.54.6"},"reference-count":49,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T00:00:00Z","timestamp":1783036800000},"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. Immunol."],"abstract":"<jats:p>\n                    As an essential component of the immune system, antibodies are among the most rigorously studied molecules in the biosciences; they combine antigen recognition with isotype-dependent effector functions. Despite this, allosteric communication within antibodies and the resulting effects on antigen-binding affinities, specifically those conferred by antibody class (isotype) or subclass, remain poorly understood. Using surface plasmon resonance, we performed a comprehensive comparison of IgA\n                    <jats:sub>1<\/jats:sub>\n                    , IgD, IgE, IgG\n                    <jats:sub>1<\/jats:sub>\n                    , IgG\n                    <jats:sub>4<\/jats:sub>\n                    and IgM Fabs across five distinct antibody-antigen systems. While different C\n                    <jats:sub>H<\/jats:sub>\n                    1 domains produced small, medium-range allosteric differences in affinity, we identified much larger, long-range effects transmitted from the Fc region to the Fab region. Full-length antibodies consistently exhibited higher binding affinities than their Fab counterparts, independent of avidity. Thermodynamic analysis indicates these effects are driven by differences in antibody flexibility and pre-organization. Taken together, these findings demonstrate that allosteric modulation of antigen binding - mediated by the C\n                    <jats:sub>H<\/jats:sub>\n                    1 domain, the Fc region, and Fc-ligand interactions - is a critical determinant of antibody function, offering essential insights for the assessment and engineering of diverse therapeutic formats.\n                  <\/jats:p>","DOI":"10.3389\/fimmu.2026.1865402","type":"journal-article","created":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T04:22:51Z","timestamp":1783052571000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Long-range allosteric communication within antibodies affects antigen-binding affinity"],"prefix":"10.3389","volume":"17","author":[{"given":"Susan K.","family":"Vester","sequence":"first","affiliation":[{"name":"Randall Centre for Cell and Molecular Biophysics, King\u2019s College London, New Hunt\u2019s 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