{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T20:18:00Z","timestamp":1788985080480,"version":"build-2803163510"},"reference-count":50,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T00:00:00Z","timestamp":1753315200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NSERC Discovery","award":["RGPIN-2019\u20130724"],"award-info":[{"award-number":["RGPIN-2019\u20130724"]}]},{"name":"Children hospital of Philadelphia Individual Development Fund","award":["RGPIN-2019\u20130724"],"award-info":[{"award-number":["RGPIN-2019\u20130724"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: Chitosan, a family of polysaccharides composed of glucosamine and N-acetyl glucosamine, is a promising adjuvant candidate for eliciting potent immune response. Methods: This study compared the adjuvant effects of chitosan to those of empty lipid nanoparticles (eLNPs) and aluminum hydroxide (alum) following administration of recombinant SARS-CoV-2 spike immunogen in adult mice. Mice received the adjuvanted recombinant protein vaccine in a prime-boost regimen with four weeks interval. Subsequent analyses included serological assessment of antibody responses, evaluation of T cell activity, immune cell recruitment and cytokine profiles at injection site. Results: Compared to alum, chitosan induced a more balanced Th1\/Th2 response, akin to that observed with eLNPs, demonstrating its ability to modulate both the humoral and cellular immune pathways. Chitosan induced a different proinflammatory cytokine (e.g., IL-1\u237a, IL-2, IL-6, and IL-7) and chemokine (e.g., Eotaxin, IP-10, MIP-1a) profile compared to eLNPs and alum at the injection site and in the draining lymph nodes. Moreover, chitosan potentiated the recruitment of innate immune cells, with neutrophils accounting for about 40% of the infiltrating cells in the muscle, representing a ~10-fold increase compared to alum and a comparable level to eLNPs. Conclusions: These findings collectively indicate that chitosan has the potential to serve as an effective adjuvant, offering comparable, and potentially superior, properties to those of currently approved adjuvants.<\/jats:p>","DOI":"10.3390\/vaccines13080788","type":"journal-article","created":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T11:58:53Z","timestamp":1753358333000},"page":"788","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Comparative Analysis of Chitosan, Lipid Nanoparticles, and Alum Adjuvants in Recombinant SARS-CoV-2 Vaccine: An Evaluation of Their Immunogenicity and Serological Efficacy"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9651-5014","authenticated-orcid":false,"given":"Majed","family":"Ghattas","sequence":"first","affiliation":[{"name":"Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC H3T 1J4, Canada"},{"name":"Department of Chemical Engineering, Polytechnique Montreal, Montreal, QC H3T 1J4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Garima","family":"Dwivedi","sequence":"additional","affiliation":[{"name":"Department of Pathology and Lab Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA"},{"name":"Penn Institute for RNA Innovation, University of Pennsylvania, Philadelphia, PA 19104, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anik","family":"Chevrier","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Polytechnique Montreal, Montreal, QC H3T 1J4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Trevor","family":"Scobey","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rakan","family":"El-Mayta","sequence":"additional","affiliation":[{"name":"Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8317-5284","authenticated-orcid":false,"given":"Melissa D.","family":"Mattocks","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dong","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Polytechnique Montreal, Montreal, QC H3T 1J4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2750-3607","authenticated-orcid":false,"given":"Marc","family":"Lavertu","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC H3T 1J4, Canada"},{"name":"Department of Chemical Engineering, Polytechnique Montreal, Montreal, QC H3T 1J4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5672-6930","authenticated-orcid":false,"given":"Mohamad-Gabriel","family":"Alameh","sequence":"additional","affiliation":[{"name":"Department of Pathology and Lab Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA"},{"name":"Penn Institute for RNA Innovation, University of Pennsylvania, Philadelphia, PA 19104, USA"},{"name":"Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children Hospital of Philadelphia Research Institute, Philadelphia, PA 19104, USA"},{"name":"Department of Experimental Pathology, Children Hospital of Philadelphia, Philadelphia, PA 19104, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ghattas, M., Dwivedi, G., Lavertu, M., and Alameh, M.-G. (2021). Vaccine Technologies and Platforms for Infectious Diseases: Current Progress, Challenges, and Opportunities. Vaccines, 9.","DOI":"10.3390\/vaccines9121490"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1597","DOI":"10.1038\/nm.3409","article-title":"Key roles of adjuvants in modern vaccines","volume":"19","author":"Reed","year":"2013","journal-title":"Nat. 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