{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T20:09:30Z","timestamp":1770062970370,"version":"3.49.0"},"reference-count":50,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,1,30]],"date-time":"2024-01-30T00:00:00Z","timestamp":1706572800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"College of Pharmacy Internal Grant","award":["CC00355"],"award-info":[{"award-number":["CC00355"]}]},{"name":"College of Pharmacy Internal Grant","award":["225945"],"award-info":[{"award-number":["225945"]}]},{"name":"Mercer University Seed Grant","award":["CC00355"],"award-info":[{"award-number":["CC00355"]}]},{"name":"Mercer University Seed Grant","award":["225945"],"award-info":[{"award-number":["225945"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>The molecule (S)-4,5-dihydroxy-2,3-pentanedione (DPD) is produced by many different species of bacteria and is involved in bacterial communication. DPD is the precursor of signal molecule autoinducer-2 (AI-2) and has high potential to be used as a vaccine adjuvant. Vaccine adjuvants are compounds that enhance the stability and immunogenicity of vaccine antigens, modulate efficacy, and increase the immune response to a particular antigen. Previously, the microparticulate form of (S)-DPD was found to have an adjuvant effect with the gonorrhea vaccine. In this study, we evaluated the immunogenicity and adjuvanticity of several synthetic analogs of the (S)-DPD molecule, including ent\u2014DPD((R)-4,5-dihydroxy-2,3-pentanedione), n-butyl\u2014DPD ((S)-1,2-dihydroxy-3,4-octanedione), isobutyl\u2014DPD ((S)-1,2-dihydroxy-6-methyl-3,4-heptanedione), n-hexyl\u2014DPD ((S)-1,2-dihydroxy-3,4-decanedione), and phenyl\u2014DPD ((S)-3,4-dihydroxy-1-phenyl-1,2-butanedione), in microparticulate formulations. The microparticulate formulations of all analogs of (S)-DPD were found to be noncytotoxic toward dendritic cells. Among these analogs, ent\u2014DPD, n-butyl\u2014DPD, and isobutyl\u2014DPD were found to be immunogenic toward antigens and showed adjuvant efficacy with microparticulate gonorrhea vaccines. It was observed that n-hexyl\u2014DPD and phenyl\u2014DPD did not show any adjuvant effect. This study shows that synthetic analogs of (S)-DPD molecules are capable of eliciting adjuvant effects with vaccines. A future in vivo evaluation will further confirm that these analogs are promising vaccine adjuvants.<\/jats:p>","DOI":"10.3390\/ph17020184","type":"journal-article","created":{"date-parts":[[2024,1,30]],"date-time":"2024-01-30T11:35:34Z","timestamp":1706614534000},"page":"184","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Potential of DPD ((S)-4,5-dihydroxy-2,3-pentanedione) Analogs in Microparticulate Formulation as Vaccine Adjuvants"],"prefix":"10.3390","volume":"17","author":[{"given":"Devyani","family":"Joshi","sequence":"first","affiliation":[{"name":"Center for Drug Delivery Research, Vaccine Nanotechnology Laboratory, College of Pharmacy, Mercer University, Atlanta, GA 30341, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sarthak","family":"Shah","sequence":"additional","affiliation":[{"name":"Center for Drug Delivery Research, Vaccine Nanotechnology Laboratory, College of Pharmacy, Mercer University, Atlanta, GA 30341, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christiane","family":"Chbib","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Larkin University, 18301 N Miami Ave, Miami, FL 33169, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohammad N.","family":"Uddin","sequence":"additional","affiliation":[{"name":"Center for Drug Delivery Research, Vaccine Nanotechnology Laboratory, College of Pharmacy, Mercer University, Atlanta, GA 30341, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3752","DOI":"10.1016\/j.vaccine.2007.01.111","article-title":"Vaccine adjuvants revisited","volume":"25","author":"Aguilar","year":"2007","journal-title":"Vaccine"},{"key":"ref_2","unstructured":"Baba, T.A.M., and Akashi, M. 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