{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T13:34:54Z","timestamp":1792762494707,"version":"4.5.0"},"reference-count":67,"publisher":"American Society for Microbiology","issue":"13","license":[{"start":{"date-parts":[[2013,7,1]],"date-time":"2013-07-01T00:00:00Z","timestamp":1372636800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["Appl Environ Microbiol"],"published-print":{"date-parts":[[2013,7]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n          <jats:p>\n            Infectious diseases disproportionately affect indigent regions and are the greatest cause of childhood mortality in developing countries. Practical, low-cost vaccines for use in these countries are paramount to reducing disease burdens and concomitant poverty. Algae are a promising low-cost system for producing vaccines that can be orally delivered, thereby avoiding expensive purification and injectable delivery. We engineered the chloroplast of the eukaryotic alga\n            <jats:named-content content-type=\"genus-species\">Chlamydomonas reinhardtii<\/jats:named-content>\n            to produce a chimeric protein consisting of the 25-kDa\n            <jats:named-content content-type=\"genus-species\">Plasmodium falciparum<\/jats:named-content>\n            surface protein (Pfs25) fused to the \u03b2 subunit of the cholera toxin (CtxB) to investigate an alga-based whole-cell oral vaccine. Pfs25 is a promising malaria transmission-blocking vaccine candidate that has been difficult to produce in traditional recombinant systems due to its structurally complex tandem repeats of epidermal growth factor-like domains. The noncatalytic CtxB domain of the cholera holotoxin assembles into a pentameric structure and acts as a mucosal adjuvant by binding GM1 ganglioside receptors on gut epithelial cells. We demonstrate that CtxB-Pfs25 accumulates as a soluble, properly folded and functional protein within algal chloroplasts, and it is stable in freeze-dried alga cells at ambient temperatures. In mice, oral vaccination using freeze-dried algae that produce CtxB-Pfs25 elicited CtxB-specific serum IgG antibodies and both CtxB- and Pfs25-specific secretory IgA antibodies. These data suggest that algae are a promising system for production and oral delivery of vaccine antigens, but as an orally delivered adjuvant, CtxB is best suited for eliciting secretory IgA antibodies for vaccine antigens against pathogens that invade mucosal surfaces using this strategy.\n          <\/jats:p>","DOI":"10.1128\/aem.00714-13","type":"journal-article","created":{"date-parts":[[2013,4,19]],"date-time":"2013-04-19T23:18:42Z","timestamp":1366413522000},"page":"3917-3925","update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":121,"title":["Alga-Produced Cholera Toxin-Pfs25 Fusion Proteins as Oral Vaccines"],"prefix":"10.1128","volume":"79","author":[{"given":"James A.","family":"Gregory","sequence":"first","affiliation":[{"name":"Division of Biological Sciences and the San Diego Center for Algae Biotechnology, University of California, San Diego, La Jolla, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aaron B.","family":"Topol","sequence":"additional","affiliation":[{"name":"Division of Biological Sciences and the San Diego Center for Algae Biotechnology, University of California, San Diego, La Jolla, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David Z.","family":"Doerner","sequence":"additional","affiliation":[{"name":"Division of Biological Sciences and the San Diego Center for Algae Biotechnology, University of California, San Diego, La Jolla, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen","family":"Mayfield","sequence":"additional","affiliation":[{"name":"Division of Biological Sciences and the San Diego Center for Algae Biotechnology, University of California, San Diego, La Jolla, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","reference":[{"key":"e_1_3_3_2_2","volume-title":"Global health observatory data repository, cause-specific mortality","author":"WHO","year":"2008","unstructured":"WHO. 2008. Global health observatory data repository, cause-specific mortality. WHO, Geneva, Switzerland."},{"key":"e_1_3_3_3_2","volume-title":"Estimates of vaccine coverage 1980\u20132011: 2012 update","author":"WHO\/UNICEF","year":"2012","unstructured":"WHO\/UNICEF. 2012. Estimates of vaccine coverage 1980\u20132011: 2012 update. WHO, Geneva, Switzerland."},{"key":"e_1_3_3_4_2","volume-title":"The world health statistics","author":"WHO","year":"2012","unstructured":"WHO. 2012. The world health statistics. WHO, Geneva, Switzerland."},{"key":"e_1_3_3_5_2","doi-asserted-by":"publisher","DOI":"10.1186\/1475-2875-11-15"},{"key":"e_1_3_3_6_2","first-page":"859","article-title":"Model-based estimates of risks of disease transmission and economic costs of seven injection devices in sub-Saharan Africa","volume":"80","author":"Ekwueme DU","year":"2002","unstructured":"EkwuemeDU WenigerBG ChenRT. 2002. Model-based estimates of risks of disease transmission and economic costs of seven injection devices in sub-Saharan Africa. Bull. World Health Organ. 80:859\u2013870.","journal-title":"Bull. World Health Organ"},{"key":"e_1_3_3_7_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.addr.2005.12.003"},{"key":"e_1_3_3_8_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2011.11.090"},{"key":"e_1_3_3_9_2","doi-asserted-by":"publisher","DOI":"10.1038\/nri1728"},{"key":"e_1_3_3_10_2","doi-asserted-by":"publisher","DOI":"10.1053\/j.gastro.2004.01.028"},{"key":"e_1_3_3_11_2","doi-asserted-by":"publisher","DOI":"10.1038\/nri1057"},{"key":"e_1_3_3_12_2","doi-asserted-by":"publisher","DOI":"10.3181\/00379727-61-15294P"},{"key":"e_1_3_3_13_2","doi-asserted-by":"publisher","DOI":"10.1007\/978-0-387-09550-9_1"},{"key":"e_1_3_3_14_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2010.11.091"},{"key":"e_1_3_3_15_2","first-page":"153","article-title":"Cholera toxin\u2014a foe & a friend","volume":"133","author":"Sanchez J","year":"2011","unstructured":"SanchezJ HolmgrenJ. 2011. Cholera toxin\u2014a foe & a friend. Indian J. Med. Res. 133:153\u2013163.","journal-title":"Indian J. Med. Res"},{"key":"e_1_3_3_16_2","doi-asserted-by":"publisher","DOI":"10.1155\/2011\/289597"},{"key":"e_1_3_3_17_2","doi-asserted-by":"publisher","DOI":"10.1038\/35074106"},{"key":"e_1_3_3_18_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2008.09.045"},{"key":"e_1_3_3_19_2","first-page":"103","article-title":"The potential of CpG oligodeoxynucleotides as mucosal adjuvants","volume":"21","author":"McCluskie MJ","year":"2001","unstructured":"McCluskieMJ WeeratnaRD PayettePJ DavisHL. 2001. The potential of CpG oligodeoxynucleotides as mucosal adjuvants. Crit. Rev. Immunol. 21:103\u2013120.","journal-title":"Crit. Rev. Immunol"},{"key":"e_1_3_3_20_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.ppat.1001147"},{"key":"e_1_3_3_21_2","doi-asserted-by":"publisher","DOI":"10.1016\/0923-2508(94)90031-0"},{"key":"e_1_3_3_22_2","unstructured":"U.S. Food and Drug Administration. 2012 posting date. GRAS notice inventory. FDA Silver Spring MD. http:\/\/www.accessdata.fda.gov\/scripts\/fcn\/fcnNavigation.cfm?rpt=graslisting."},{"key":"e_1_3_3_23_2","doi-asserted-by":"publisher","DOI":"10.1038\/nrg1177"},{"key":"e_1_3_3_24_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.7732379"},{"key":"e_1_3_3_25_2","doi-asserted-by":"publisher","DOI":"10.1038\/nbt0802-777"},{"key":"e_1_3_3_26_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0020-7519(03)00052-3"},{"key":"e_1_3_3_27_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.320.5875.473"},{"key":"e_1_3_3_28_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0606631103"},{"key":"e_1_3_3_29_2","doi-asserted-by":"publisher","DOI":"10.1104\/pp.125.4.1543"},{"key":"e_1_3_3_30_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.191617598"},{"key":"e_1_3_3_31_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.copbio.2008.07.008"},{"key":"e_1_3_3_32_2","volume-title":"National algal biofuels technology roadmap","author":"DOE","year":"2010","unstructured":"DOE. 2010. National algal biofuels technology roadmap. Department of Energy, Biomass Program, Washington, DC."},{"key":"e_1_3_3_33_2","doi-asserted-by":"publisher","DOI":"10.1007\/s00253-012-4071-7"},{"key":"e_1_3_3_34_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.biologicals.2009.02.005"},{"key":"e_1_3_3_35_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0043349"},{"key":"e_1_3_3_36_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0237108100"},{"key":"e_1_3_3_37_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1467-7652.2010.00503.x"},{"key":"e_1_3_3_38_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1214638110"},{"key":"e_1_3_3_39_2","doi-asserted-by":"publisher","DOI":"10.1007\/s11120-004-2216-y"},{"key":"e_1_3_3_40_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.278.5345.1954"},{"key":"e_1_3_3_41_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0021-9258(19)36605-0"},{"key":"e_1_3_3_42_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pbio.0050209"},{"key":"e_1_3_3_43_2","doi-asserted-by":"publisher","DOI":"10.1038\/333074a0"},{"key":"e_1_3_3_44_2","doi-asserted-by":"publisher","DOI":"10.1099\/00221287-76-2-417"},{"key":"e_1_3_3_45_2","first-page":"193","article-title":"Structure and mechanism of a transmission blocking vaccine candidate protein Pfs25 from P. falciparum: a molecular modeling and docking study","volume":"8","author":"Sharma B","year":"2008","unstructured":"SharmaB. 2008. Structure and mechanism of a transmission blocking vaccine candidate protein Pfs25 from P. falciparum: a molecular modeling and docking study. In Silico Biol. 8:193\u2013206.","journal-title":"In Silico Biol"},{"key":"e_1_3_3_46_2","doi-asserted-by":"publisher","DOI":"10.1128\/IAI.66.1.59-64.1998"},{"key":"e_1_3_3_47_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0037179"},{"key":"e_1_3_3_48_2","doi-asserted-by":"publisher","DOI":"10.1186\/1745-6150-3-38"},{"key":"e_1_3_3_49_2","doi-asserted-by":"publisher","DOI":"10.1093\/nar\/gkl635"},{"key":"e_1_3_3_50_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.274.30.20745"},{"key":"e_1_3_3_51_2","doi-asserted-by":"publisher","DOI":"10.4161\/bbug.2.1.13423"},{"key":"e_1_3_3_52_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1467-7652.2007.00249.x"},{"key":"e_1_3_3_53_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.2897716"},{"key":"e_1_3_3_54_2","doi-asserted-by":"publisher","DOI":"10.1007\/BF02172529"},{"key":"e_1_3_3_55_2","doi-asserted-by":"publisher","DOI":"10.1128\/iai.60.7.2874-2879.1992"},{"key":"e_1_3_3_56_2","doi-asserted-by":"publisher","DOI":"10.1093\/nar\/15.3.1281"},{"key":"e_1_3_3_57_2","doi-asserted-by":"publisher","DOI":"10.1084\/jem.174.5.1203"},{"key":"e_1_3_3_58_2","doi-asserted-by":"publisher","DOI":"10.1006\/jmbi.1995.0455"},{"key":"e_1_3_3_59_2","doi-asserted-by":"publisher","DOI":"10.1128\/IAI.70.6.3111-3121.2002"},{"key":"e_1_3_3_60_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2011.09.010"},{"key":"e_1_3_3_61_2","doi-asserted-by":"publisher","DOI":"10.1038\/nm1219"},{"key":"e_1_3_3_62_2","doi-asserted-by":"publisher","DOI":"10.1038\/nm0502-518"},{"key":"e_1_3_3_63_2","doi-asserted-by":"publisher","DOI":"10.1002\/bit.21244"},{"key":"e_1_3_3_64_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jbiotec.2009.12.006"},{"key":"e_1_3_3_65_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.coi.2012.03.014"},{"key":"e_1_3_3_66_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.addr.2009.11.012"},{"key":"e_1_3_3_67_2","doi-asserted-by":"publisher","DOI":"10.1186\/1477-3155-9-55"},{"key":"e_1_3_3_68_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.biortech.2011.08.010"}],"container-title":["Applied and Environmental Microbiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/AEM.00714-13","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/AEM.00714-13","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,2,23]],"date-time":"2022-02-23T14:42:49Z","timestamp":1645627369000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/AEM.00714-13"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2013,7]]},"references-count":67,"journal-issue":{"issue":"13","published-print":{"date-parts":[[2013,7]]}},"alternative-id":["10.1128\/AEM.00714-13"],"URL":"https:\/\/doi.org\/10.1128\/aem.00714-13","relation":{},"ISSN":["0099-2240","1098-5336"],"issn-type":[{"value":"0099-2240","type":"print"},{"value":"1098-5336","type":"electronic"}],"subject":[],"published":{"date-parts":[[2013,7]]},"assertion":[{"value":"2013-03-01","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2013-04-02","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2013-06-06","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}