{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T05:47:07Z","timestamp":1782539227186,"version":"3.54.5"},"reference-count":45,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T00:00:00Z","timestamp":1782345600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"crossref","award":["U01 AI148114"],"award-info":[{"award-number":["U01 AI148114"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"crossref","award":["R01 AI187028"],"award-info":[{"award-number":["R01 AI187028"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100000015","name":"Department of Energy","doi-asserted-by":"crossref","award":["GUP-48455"],"award-info":[{"award-number":["GUP-48455"]}],"id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibodies"],"abstract":"<jats:p>Background: The interaction between human immunoglobulin G (IgG)1 Fc and the Fc gamma receptor (Fc\u03b3R) IIIa\/CD16a elicits protective immune responses. Antibody N-glycosylation stabilizes the Fc\u03b3R-binding interface and is thus essential for interaction with wildtype IgG1 Fc. Furthermore, the N-glycan introduces substantial compositional and functional heterogeneity, with distinct glycoforms providing different affinities and discrete responses in vivo. Accordingly, various engineering endeavors to improve antibody binding strive to boost the therapeutic efficacy of monoclonal antibodies but do not directly address compositional heterogeneity. Objective: Here, we describe a previously unexplored approach to engineer IgG1 Fc. We eliminated carbohydrate heterogeneity by removing the N-glycan but stabilizing the Fc\u03b3R-binding interface with disulfide bonds. Conclusions: These newly generated Fc domains served as a starting point for protein engineering through yeast surface display to enhance receptor-binding affinity. We recovered Fc variants from this approach that demonstrated Fc\u03b3RIIIa binding affinities comparable to the starting sequence and thus serve as a proof-of-principle for this strategy.<\/jats:p>","DOI":"10.3390\/antib15040055","type":"journal-article","created":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T08:14:12Z","timestamp":1782375252000},"page":"55","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Aglycosylated Immunoglobulin G1 Fc Stabilized Through Disulfide Bond Addition Exhibits Compositional Homogeneity and Retains Fc \u03b3 Receptor IIIa\/CD16a Binding"],"prefix":"10.3390","volume":"15","author":[{"given":"Anjali","family":"Shenoy","sequence":"first","affiliation":[{"name":"Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel J.","family":"Falconer","sequence":"additional","affiliation":[{"name":"Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3290-8649","authenticated-orcid":false,"given":"Adam W.","family":"Barb","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA"},{"name":"Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA"},{"name":"Department of Chemistry, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zahavi, D., and Weiner, L. (2020). Monoclonal Antibodies in Cancer Therapy. 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