{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:58:59Z","timestamp":1760147939690,"version":"build-2065373602"},"reference-count":55,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,13]],"date-time":"2023-03-13T00:00:00Z","timestamp":1678665600000},"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":"publisher","award":["AR063910","AI073539"],"award-info":[{"award-number":["AR063910","AI073539"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Vitamin D is known to modulate human immune responses, and vitamin D deficiency is associated with increased susceptibility to infection. However, what constitutes sufficient levels or whether vitamin D is useful as an adjuvant therapeutic is debated, much in part because of inadequate elucidation of mechanisms underlying vitamin D\u2019s immune modulatory function. Cathelicidin antimicrobial peptide (CAMP) has potent broad-spectrum activity, and the CAMP gene is regulated in human innate immune cells by active 1,25(OH)2D3, a product of hydroxylation of inactive 25(OH)D3 by CYP27B1-hydroxylase. We developed a CRISPR\/Cas9-edited human monocyte-macrophage cell line containing the mCherry fluorescent reporter gene at the 3\u2032 end of the endogenous CAMP gene. The High Throughput CAMP Assay (HiTCA) developed here is a novel tool for evaluating CAMP expression in a stable cell line that is scalable for a high-throughput workflow. Application of HiTCA to serum samples from a small number of human donors (n = 10) showed individual differences in CAMP induction that were not fully accounted for by the serum vitamin D metabolite status of the host. As such, HiTCA may be a useful tool that can advance our understanding of the human vitamin D-dependent antimicrobial response, which is being increasingly appreciated for its complexity.<\/jats:p>","DOI":"10.3390\/nu15061380","type":"journal-article","created":{"date-parts":[[2023,3,13]],"date-time":"2023-03-13T02:31:55Z","timestamp":1678674715000},"page":"1380","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["High-Throughput CAMP Assay (HiTCA): A Novel Tool for Evaluating the Vitamin D-Dependent Antimicrobial Response"],"prefix":"10.3390","volume":"15","author":[{"given":"Carter","family":"Gottlieb","sequence":"first","affiliation":[{"name":"Department of Orthopaedic Surgery, University of California, Los Angeles, CA 90095, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2448-2329","authenticated-orcid":false,"given":"Mason","family":"Henrich","sequence":"additional","affiliation":[{"name":"Department of Molecular, Cell & Developmental Biology, University of California, Los Angeles, CA 90095, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Philip T.","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA 90095, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2861-7603","authenticated-orcid":false,"given":"Vahe","family":"Yacoubian","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, University of California, Los Angeles, CA 90095, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeffery","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, University of California, Los Angeles, CA 90095, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0190-0807","authenticated-orcid":false,"given":"Rene","family":"Chun","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, University of California, Los Angeles, CA 90095, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John S.","family":"Adams","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, University of California, Los Angeles, CA 90095, USA"},{"name":"Department of Molecular, Cell & Developmental Biology, University of California, Los Angeles, CA 90095, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1079","DOI":"10.2174\/1381612824666180327113418","article-title":"Tissue-specific regulation of innate immune responses by human cathelicidin LL-37","volume":"24","author":"Chieosilapatham","year":"2018","journal-title":"Curr. 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