{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T00:07:57Z","timestamp":1788826077139,"version":"build-2803163510"},"reference-count":21,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T00:00:00Z","timestamp":1767312000000},"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. Pharmacol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Investigational immunomodulatory drugs are often initially investigated in healthy volunteers, which lack drug-target engagement biomarkers, hampering evaluation of pharmacodynamic effects. A model such as the Keyhole Limpet Hemocyanin (KLH) neoantigen challenge induces a well-controlled adaptive immune response and can be used to study pharmacodynamic effects in healthy volunteers. To increase our understanding of sources of variability in KLH-induced responses, we integrated KLH data from multiple studies executed at our research institute and investigated the contribution of covariates to KLH challenge responses.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We performed a pooled analysis of seven KLH trials with standardized methodology and design. Included trials immunized participants with KLH one, two or three times, with an interval of 2\u00a0weeks, followed by subsequent intradermal KLH administration 2\u20133\u00a0weeks after the final immunization. Differences and correlations were calculated between anti-KLH IgM and IgG and skin perfusion, flare, and erythema. A mixed effects model analysis was performed to estimate variances and determine the effect of the number of immunizations and the systemic and local biomarkers on the sample size. Finally, the effect of covariates age, sex, and body mass index was analyzed.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 68 participants were included: 42 participants were immunized with KLH once, 5 participants twice, and 21 participants three times. Three times immunization resulted in significantly higher antibody levels, cutaneous perfusion, and flare. A study design incorporating three immunizations and skin imaging at 24\u00a0h was found to have the most robust statistical power. Lastly, the systemic KLH response correlated negatively with age and positively with local KLH responses.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>This analysis provides a basis for the design of future clinical studies with KLH challenges. These data provide further insights into the performance of the human KLH challenge, which will facilitate the implementation of this immune challenge model in future clinical pharmacology studies.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphar.2025.1717333","type":"journal-article","created":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T06:28:36Z","timestamp":1767335316000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Neoantigen immune responses in healthy volunteers: insights from multiple integrated keyhole limpet hemocyanin challenge studies on repeated immunization and response covariates"],"prefix":"10.3389","volume":"16","author":[{"given":"Micha N.","family":"Ronner","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marieke L.","family":"De Kam","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silke","family":"Van Reeuwijk","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacobus","family":"Burggraaf","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manon A. A.","family":"Jansen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthijs","family":"Moerland","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,2]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"389","DOI":"10.1007\/S00011-016-0923-4","article-title":"Characterisation of the clinical and activated T cell response to repeat delayed-type hypersensitivity skin challenges in human subjects, with KLH and PPD, as a potential model to test T cell-targeted therapies","volume":"65","author":"Belson","year":"2016","journal-title":"Inflamm. Res."},{"key":"B2","doi-asserted-by":"publisher","first-page":"1879","DOI":"10.1177\/0091270011427908","article-title":"Pharmacodynamic effects of steady-state fingolimod on antibody response in healthy volunteers: a 4-week, randomized, placebo-controlled, parallel-group, multiple-dose study","volume":"52","author":"Boulton","year":"2012","journal-title":"J. Clin Pharmacol"},{"key":"B3","doi-asserted-by":"publisher","first-page":"680","DOI":"10.1111\/BCP.14999","article-title":"Intradermal lipopolysaccharide challenge as an acute in vivo inflammatory model in healthy volunteers","volume":"88","author":"Buters","year":"2022","journal-title":"Br. J. Clin. Pharmacol."},{"key":"B4","doi-asserted-by":"publisher","first-page":"309","DOI":"10.1111\/ACEL.12326","article-title":"How sex and age affect immune responses, susceptibility to infections, and response to vaccination","volume":"14","author":"Giefing-Kr\u00f6ll","year":"2015","journal-title":"Aging Cell"},{"key":"B5","doi-asserted-by":"publisher","first-page":"3981","DOI":"10.4049\/JIMMUNOL.1701728","article-title":"Simultaneous presence of Non- and highly mutated keyhole limpet hemocyanin (KLH)-specific plasmablasts early after primary KLH immunization suggests cross-reactive memory B cell activation","volume":"200","author":"Giesecke","year":"2018","journal-title":"J. Immunology"},{"key":"B6","doi-asserted-by":"publisher","first-page":"1797","DOI":"10.1007\/S00296-022-05134-Z","article-title":"Tuberculin skin test before biologic and targeted therapies: does the same rule apply for all?","volume":"42","author":"\u0130lgen","year":"2022","journal-title":"Rheumatol. International"},{"key":"B7","doi-asserted-by":"publisher","first-page":"2015","DOI":"10.1097\/00002030-200309260-00002","article-title":"Nadir CD4+ T-cell count and numbers of CD28+ CD4+ T-cells predict functional responses to immunizations in chronic HIV-1 infection","volume":"17","author":"Lange","year":"2003","journal-title":"AIDS"},{"key":"B8","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1038\/S41392-023-01451-2","article-title":"Immunosenescence: molecular mechanisms and diseases","volume":"8","author":"Liu","year":"2023","journal-title":"Signal Transduct. Target. Ther."},{"key":"B9","doi-asserted-by":"publisher","first-page":"1364","DOI":"10.4161\/HV.24696","article-title":"The effect of ageing of the immune system on vaccination responses","volume":"9","author":"Lord","year":"2013","journal-title":"Hum. Vaccines Immunotherapeutics"},{"key":"B10","doi-asserted-by":"publisher","first-page":"3","DOI":"10.1016\/J.JID.2019.11.003","article-title":"Research techniques made simple: cutaneous colorimetry: a reliable technique for objective skin color measurement","volume":"140","author":"Ly","year":"2020","journal-title":"J. Investigative Dermatology"},{"key":"B11","doi-asserted-by":"publisher","first-page":"269","DOI":"10.1159\/000328784","article-title":"Response to cutaneous immunization with low-molecular-weight subunit keyhole limpet hemocyanin","volume":"157","author":"Milgrom","year":"2012","journal-title":"Int. Archives Allergy Immunology"},{"key":"B12","doi-asserted-by":"publisher","first-page":"144","DOI":"10.1016\/j.clim.2005.07.005","article-title":"Diminished neo-antigen response to keyhole limpet hemocyanin (KLH) vaccines in patients after treatment with chemotherapy or hematopoietic cell transplantation","volume":"117","author":"Miller","year":"2005","journal-title":"Clin. Immunol."},{"key":"B13","volume-title":"A language and environment for statistical computing","year":"2023"},{"key":"B14","doi-asserted-by":"publisher","first-page":"1132","DOI":"10.1002\/CPT.70007","article-title":"Profiling a neo-antigen-driven immune response in healthy volunteers: a randomized, double-blind, placebo-controlled study of the KLH challenge model","volume":"118","author":"Ronner","year":"2025","journal-title":"Clin. Pharmacology Therapeutics"},{"key":"B15","doi-asserted-by":"publisher","first-page":"1953","DOI":"10.1111\/bcp.14588","article-title":"A randomized controlled trial with a delayed-type hypersensitivity model using keyhole limpet haemocyanin to evaluate adaptive immune responses in man","volume":"87","author":"Saghari","year":"2021","journal-title":"Br. J. Clin. Pharmacol."},{"key":"B16","doi-asserted-by":"publisher","first-page":"992087","DOI":"10.3389\/FDDSV.2022.992087","article-title":"Characterization of KLH-driven immune responses in clinical studies: a systematic review","volume":"2","author":"Saghari","year":"2022","journal-title":"Front. Drug Discov."},{"key":"B17","doi-asserted-by":"publisher","first-page":"999","DOI":"10.1111\/J.1365-2222.2008.03177.X","article-title":"T helper 2 biased de novo immune response to Keyhole Limpet Hemocyanin in humans","volume":"39","author":"Spazierer","year":"2009","journal-title":"Clin. Experimental Allergy"},{"key":"B18","doi-asserted-by":"publisher","first-page":"1135","DOI":"10.1111\/BCP.12422","article-title":"Keyhole limpet haemocyanin - a model antigen for human immunotoxicological studies","volume":"78","author":"Swaminathan","year":"2014","journal-title":"Br. Journal Clinical Pharmacology"},{"key":"B19","doi-asserted-by":"publisher","first-page":"1366","DOI":"10.1007\/S10753-024-02127-X","article-title":"Extending the IMQ model: deep characterization of the human TLR7 response for early drug development","volume":"48","author":"van den Noort","year":"2025","journal-title":"Inflammation"},{"key":"B20","doi-asserted-by":"publisher","first-page":"445","DOI":"10.1016\/S1081-1206(10)62279-X","article-title":"Gender differences in response to the multitest CMI skin test in the general population","volume":"84","author":"Vine","year":"2000","journal-title":"Ann. Allergy, Asthma Immunol."},{"key":"B21","doi-asserted-by":"publisher","first-page":"273","DOI":"10.1093\/BIOSTATISTICS\/KXX069","article-title":"Estimation of clinical trial success rates and related parameters","volume":"20","author":"Wong","year":"2019","journal-title":"Biostatistics"}],"container-title":["Frontiers in Pharmacology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fphar.2025.1717333\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T06:28:37Z","timestamp":1767335317000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fphar.2025.1717333\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,2]]},"references-count":21,"alternative-id":["10.3389\/fphar.2025.1717333"],"URL":"https:\/\/doi.org\/10.3389\/fphar.2025.1717333","relation":{},"ISSN":["1663-9812"],"issn-type":[{"value":"1663-9812","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,2]]},"article-number":"1717333"}}