{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T12:09:59Z","timestamp":1776427799155,"version":"3.51.2"},"reference-count":43,"publisher":"FapUNIFESP (SciELO)","license":[{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"am","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Secretaria de Ciencia, Humanidades, Tecnologia e Innovacion","award":["CB2017-2018 A1-S-21831"],"award-info":[{"award-number":["CB2017-2018 A1-S-21831"]}]},{"name":"Secretaria de Ciencia, Humanidades, Tecnologia e Innovacion","award":["CBF-2025-I-4042"],"award-info":[{"award-number":["CBF-2025-I-4042"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Mem. Inst. Oswaldo Cruz"],"abstract":"<jats:p>BACKGROUND Giardia lamblia is a parasite that infects humans. To date, there is no vaccine available for human giardiasis. Thus, discovering new immunogenic antigens is crucial for the rational design of a vaccine.  OBJECTIVES This study aimed to identify the main immunogenic antigens of G. lamblia from its entire proteome using immunoinformatic and data science techniques. To our knowledge, this is the first study to systematically identify immunogenic antigens of G. lamblia across its complete proteome, providing a comprehensive map of potential immunogenic antigens.  METHODS Briefly, FASTA sequences of G. lamblia isolates WB and GS were submitted to the NetMHCII 2.3 predictor. The analysis was conducted for five murine major histocompatibility complex (MHC)-II molecules: I-Ab, I-Ad, I-Ed, I-Ak, and I-Ek. Python 3.9 was used to develop custom code for data processing and analysis.  FINDINGS We identified 414 potential immunogenic polypeptides for isolate WB and 350 for isolate GS. For both isolates, most polypeptides contained peptides with high affinity for I-Ab and I-Ek. Notably, no polypeptides with high affinity for I-Ak were detected. Homologous potential immunogenic antigens (129 polypeptides) were identified in both isolates. The analysis revealed that 12 potential immunogenic polypeptides from isolate WB and 10 from isolate GS are part of the Giardia secretome. Additionally, promiscuous polypeptides that bind to at least two different MHC-II molecules were found in both isolates.  MAIN CONCLUSIONS These findings lay a valuable foundation for the rational development of a vaccine against human giardiasis and show a computational strategy that can be applied to the study of other pathogens.<\/jats:p>","DOI":"10.1590\/0074-02760250216","type":"journal-article","created":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T11:36:01Z","timestamp":1776425761000},"source":"Crossref","is-referenced-by-count":0,"title":["Immunoinformatic analysis for identifying immunogenic antigens from the complete proteome of Giardia lamblia"],"prefix":"10.1590","volume":"121","author":[{"given":"David","family":"Ortega-Tirado","sequence":"first","affiliation":[{"name":"Universidad de Sonora,  Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carlos A","family":"Velazquez-Valdez","sequence":"additional","affiliation":[{"name":"Universidad de Sonora,  Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thania","family":"Garzon","sequence":"additional","affiliation":[{"name":"Universidad de Sonora,  Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leslie","family":"Bracamontes-Picos","sequence":"additional","affiliation":[{"name":"Universidad de Sonora,  Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gloria","family":"Lopez-Romero","sequence":"additional","affiliation":[{"name":"Universidad de Sonora,  Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3728-7848","authenticated-orcid":false,"given":"Carlos","family":"Velazquez","sequence":"additional","affiliation":[{"name":"Universidad de Sonora,  Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"530","published-online":{"date-parts":[[2026]]},"reference":[{"issue":"9","key":"ref1","doi-asserted-by":"crossref","first-page":"e1007250","DOI":"10.1371\/journal.ppat.1007250","article-title":"Five facts about Giardia lamblia","volume":"14","author":"Cernikova L","year":"2018","journal-title":"PLoS Pathog"},{"issue":"4","key":"ref2","doi-asserted-by":"crossref","first-page":"e00024-19","DOI":"10.1128\/CMR.00024-19","article-title":"Giardia duodenalis: biology and pathogenesis","volume":"34","author":"Adam RD","year":"2021","journal-title":"Clin Microbiol Rev"},{"issue":"11","key":"ref3","doi-asserted-by":"crossref","first-page":"901","DOI":"10.1016\/j.pt.2017.08.001","article-title":"The intersection of immune responses, microbiota, and pathogenesis in giardiasis","volume":"33","author":"Fink MY","year":"2017","journal-title":"Trends Parasitol"},{"issue":"8","key":"ref4","doi-asserted-by":"crossref","first-page":"394","DOI":"10.1111\/pim.12210","article-title":"Host defences against Giardia lamblia","volume":"37","author":"Lopez-Romero G","year":"2015","journal-title":"Parasite Immunol"},{"key":"ref5","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1016\/j.rvsc.2020.09.034","article-title":"Giardia duodenalis in humans and animals - Transmission and disease","volume":"135","author":"Dixon BR","year":"2021","journal-title":"Res Vet Sci"},{"key":"ref6","doi-asserted-by":"crossref","first-page":"769446","DOI":"10.3389\/fcimb.2021.769446","article-title":"Immunoinformatic identification of T-Cell and B-Cell epitopes from Giardia lamblia immunogenic proteins as candidates to develop peptide-based vaccines against giardiasis","volume":"11","author":"Garzon T","year":"2021","journal-title":"Front Cell Infect Microbiol"},{"issue":"4","key":"ref7","doi-asserted-by":"crossref","first-page":"e0010323","DOI":"10.1371\/journal.pntd.0010323","article-title":"Conserved metabolic enzymes as vaccine antigens for giardiasis","volume":"16","author":"Iharag S","year":"2022","journal-title":"PLoS Negl Trop Dis"},{"issue":"1","key":"ref8","doi-asserted-by":"crossref","first-page":"2537","DOI":"10.1038\/s41467-023-38317-8","article-title":"Antibodies to variable surface antigens induce antigenic variation in the intestinal parasite Giardia lamblia","volume":"14","author":"Tenaglia AH","year":"2023","journal-title":"Nat Commun"},{"issue":"12","key":"ref9","doi-asserted-by":"crossref","first-page":"e0006120","DOI":"10.1371\/journal.pntd.0006120","article-title":"Characterization of the Giardia intestinalis secretome during interaction with human intestinal epithelial cells: the impact on host cells","volume":"11","author":"Ma\u2019ayeh SY","year":"2017","journal-title":"PLoS Negl Trop Dis"},{"issue":"1","key":"ref10","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1128\/IAI.68.1.170-175.2000","article-title":"T-Cell-dependent control of acute Giardia lamblia infections in mice","volume":"68","author":"Singer SM","year":"2000","journal-title":"Infect Immun"},{"issue":"2","key":"ref11","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1093\/tropej\/fmz048","article-title":"Intestinal parasites infections among HIV infected children under antiretrovirals treatment in Yaounde, Cameroon","volume":"66","author":"Abange WB","year":"2020","journal-title":"J Trop Pediatr"},{"key":"ref12","first-page":"505","article-title":"Prevalence and predisposing factors of intestinal parasitic infections among HIV positive patients visiting Nekemte specialized hospital, western Ethiopia","volume":"13","author":"Miressa R","year":"2021","journal-title":"HIV AIDS (Auckl)"},{"key":"ref13","first-page":"5652637","article-title":"Intestinal parasitic infection and associated risk factors among HIV-infected patients seeking healthcare in a rural Hospital in Ghana","volume":"2022","author":"Deku JG","year":"2022","journal-title":"J Pathog"},{"issue":"4","key":"ref14","doi-asserted-by":"crossref","first-page":"362","DOI":"10.1016\/j.arcmed.2021.01.004","article-title":"Immunoinformatics approach for the identification and characterization of T Cell and B Cell epitopes towards the Peptide-Based vaccine against SARS-CoV-2","volume":"52","author":"Chakraborty C","year":"2021","journal-title":"Arch Med Res"},{"issue":"2","key":"ref15","doi-asserted-by":"crossref","first-page":"1155","DOI":"10.1007\/s10989-019-09918-z","article-title":"Epitope prediction by novel immunoinformatics approach: a state-of-the-art review","volume":"26","author":"Raoufi E","year":"2020","journal-title":"Int J Pept Res Ther"},{"key":"ref16","doi-asserted-by":"crossref","first-page":"526","DOI":"10.1093\/nar\/gkn631","article-title":"GiardiaDB and TrichDB: integrated genomic resources for the eukaryotic protist pathogens Giardia lamblia and Trichomonas vaginalis","volume":"37","author":"Aurrecoechea C","year":"2009","journal-title":"Nucleic Acids Res"},{"issue":"D1","key":"ref17","doi-asserted-by":"crossref","first-page":"808","DOI":"10.1093\/nar\/gkad1003","article-title":"VEuPathDB: the eukaryotic pathogen, vector and host bioinformatics resource center in 2023","volume":"52","author":"Alvarez-Jarreta J","year":"2024","journal-title":"Nucleic Acids Res"},{"issue":"D1","key":"ref18","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1093\/nar\/gky1006","article-title":"The immune epitope database (IEDB): 2018 update","volume":"47","author":"Vita R","year":"2019","journal-title":"Nucleic Acids Res"},{"issue":"3","key":"ref19","doi-asserted-by":"crossref","first-page":"394","DOI":"10.1111\/imm.12889","article-title":"Improved methods for predicting peptide binding affinity to MHC class II molecules","volume":"154","author":"Jensen KK","year":"2018","journal-title":"Immunology"},{"key":"ref20","doi-asserted-by":"crossref","first-page":"1001","DOI":"10.1126\/science.272.5264.1001","article-title":"Structures of an MHC Class II molecule with covalently bound single peptides","volume":"272","author":"Fremont D","year":"1996","journal-title":"Science"},{"issue":"3","key":"ref21","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1016\/S1074-7613(00)80536-1","article-title":"Crystal structure of I-Ak in complex with a dominant epitope of lysozyme","volume":"8","author":"Fremont DH","year":"1998","journal-title":"Immunity"},{"issue":"3","key":"ref22","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1016\/S1074-7613(00)80537-3","article-title":"Crystal structures of two I-Ad-peptide complexes reveal that high affinity can be achieved without large anchor residues","volume":"8","author":"Scott C","year":"1998","journal-title":"Immunity"},{"issue":"157","key":"ref23","doi-asserted-by":"crossref","first-page":"755","DOI":"10.4049\/jimmunol.157.2.755","article-title":"A negatively charged anchor residue promotes high affinity binding to the MHC Class II molecule I-Ak","volume":"2","author":"Nelson CA","year":"1996","journal-title":"J Immunol"},{"issue":"12","key":"ref24","doi-asserted-by":"crossref","first-page":"1957","DOI":"10.1093\/intimm\/7.12.1957","article-title":"Natural ligand motifs of H-2E molecules are allele specific and illustrate homology to HLA-DR molecules","volume":"7","author":"Schil H","year":"1995","journal-title":"Int Immunol"},{"issue":"2","key":"ref25","doi-asserted-by":"crossref","first-page":"347","DOI":"10.4049\/jimmunol.148.2.347","article-title":"Complete dissection of the Hb(64-76) determinant using T helper 1, T helper 2 clones, and T cell hybridomas","volume":"148","author":"Evavold BD","year":"1992","journal-title":"J Immunol"},{"issue":"6","key":"ref26","doi-asserted-by":"crossref","first-page":"2173","DOI":"10.1084\/jem.178.6.2173","article-title":"Comparison of peptides bound to spleen and thymus class II","volume":"178","author":"Philippa Marrack B","year":"1993","journal-title":"J Exp Med"},{"issue":"1","key":"ref27","doi-asserted-by":"crossref","first-page":"879","DOI":"10.1080\/21505594.2018.1451284","article-title":"Secreted Giardia intestinalis cysteine proteases disrupt intestinal epithelial cell junctional complexes and degrade chemokines","volume":"9","author":"Liua J","year":"2018","journal-title":"Virulence"},{"issue":"2","key":"ref28","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1111\/imm.12624","article-title":"Comparative genomics of the human, macaque and mouse major histocompatibility complex","volume":"150","author":"Shiina T","year":"2017","journal-title":"Immunology"},{"issue":"2","key":"ref29","first-page":"5513","article-title":"Influence of human leukocyte antigen HLA-DRB1 on susceptibility to Giardia lamblia infection of Iraqi patients","volume":"20","author":"Mohammad I","year":"2020","journal-title":"Biochem Cell Arch"},{"issue":"2","key":"ref30","doi-asserted-by":"crossref","first-page":"56","DOI":"10.4103\/1995-7645.275413","article-title":"Human leukocyte antigen class-II DRB1 alleles and Giardia lamblia infection in children: a case-control study","volume":"13","author":"El-Beshbishi S","year":"2020","journal-title":"Asian Pac J Trop Med"},{"issue":"4","key":"ref31","doi-asserted-by":"crossref","first-page":"804","DOI":"10.1016\/j.exppara.2011.01.006","article-title":"Elongation factor 1-alpha is released into the culture medium during growth of Giardia intestinalis trophozoites","volume":"127","author":"Skarin H","year":"2011","journal-title":"Exp Parasitol"},{"key":"ref32","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1016\/bs.apar.2019.11.003","article-title":"Drug resistance in Giardia: mechanisms and alternative treatments for giardiasis","volume":"107","author":"Arg\u00fcello-Garc\u00eda R","year":"2020","journal-title":"Adv Parasitol"},{"key":"ref33","doi-asserted-by":"crossref","first-page":"913","DOI":"10.3389\/fgene.2020.00913","article-title":"High cysteine membrane proteins (HCMPs) are up-regulated during Giardia-host cell interactions","volume":"11","author":"Peirasmaki D","year":"2020","journal-title":"Front Genet"},{"key":"ref34","doi-asserted-by":"crossref","first-page":"928687","DOI":"10.3389\/fcimb.2022.928687","article-title":"Giardia duodenalis enolase is secreted as monomer during trophozoite-epithelial cell interactions, activates plasminogen and induces necroptotic damage","volume":"12","author":"Barroeta-Echegaray E","year":"2022","journal-title":"Front Cell Infect Microbiol"},{"issue":"1","key":"ref35","doi-asserted-by":"crossref","first-page":"17645","DOI":"10.1038\/s41598-024-67553-1","article-title":"Multi-epitope peptide vaccines targeting dengue virus serotype 2 created via immunoinformatic analysis","volume":"14","author":"Morgan RN","year":"2024","journal-title":"Sci Rep"},{"issue":"1","key":"ref36","doi-asserted-by":"crossref","first-page":"276","DOI":"10.1186\/s12864-023-09330-4","article-title":"Employing computational tools to design a multi-epitope vaccine targeting human immunodeficiency virus-1 (HIV-1)","volume":"24","author":"Sher H","year":"2023","journal-title":"BMC Genomics"},{"issue":"12","key":"ref37","doi-asserted-by":"crossref","first-page":"e0012757","DOI":"10.1371\/journal.pntd.0012757","article-title":"Efficacy of vaccines based on chimeric or multiepitope antigens for protection against visceral leishmaniasis: a systematic review","volume":"18","author":"Lopes KF","year":"2024","journal-title":"PLoS Negl Trop Dis"},{"issue":"10","key":"ref38","doi-asserted-by":"crossref","first-page":"e2303531","DOI":"10.1002\/adhm.202303531","article-title":"Self-Assembled multiepitope nanovaccine provides long-lasting cross-protection against influenza virus","volume":"13","author":"Nie J","year":"2024","journal-title":"Adv Healthc Mater"},{"issue":"10","key":"ref39","doi-asserted-by":"crossref","first-page":"e12767","DOI":"10.1111\/pim.12767","article-title":"Differential antibody responses to Giardia lamblia strain variants expressing dissimilar levels of an immunogenic protein","volume":"42","author":"Garzon T","year":"2020","journal-title":"Parasite Immunol"},{"issue":"8-9","key":"ref40","doi-asserted-by":"crossref","first-page":"884","DOI":"10.1016\/j.imbio.2017.05.008","article-title":"Characterization of BIP protein of G. lamblia as a potential immunogen in a mouse infection model","volume":"222","author":"Lopez-Romero G","year":"2017","journal-title":"Immunobiology"},{"issue":"9","key":"ref41","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1111\/j.1365-3024.2005.00793.x","article-title":"Giardia lamblia infection induces different secretory and systemic antibody responses in mice","volume":"27","author":"Velazquez C","year":"2005","journal-title":"Parasite Immunol"},{"key":"ref42","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1016\/j.coi.2014.12.005","article-title":"Determinants of immunodominance for CD4 T cells","volume":"34","author":"Kim AR","year":"2015","journal-title":"Curr Opin Immunol"},{"issue":"5-6","key":"ref43","first-page":"411","article-title":"Antigen-presenting cells and the selection of immunodominant epitopes","volume":"17","author":"Blum JS","year":"1997","journal-title":"Crit Rev Immunol"}],"container-title":["Mem\u00f3rias do Instituto Oswaldo Cruz"],"original-title":[],"link":[{"URL":"http:\/\/www.scielo.br\/scielo.php?script=sci_pdf&pid=S0074-02762026000105027&tlng=en","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T11:36:07Z","timestamp":1776425767000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.scielo.br\/scielo.php?script=sci_arttext&pid=S0074-02762026000105027&tlng=en"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026]]},"references-count":43,"alternative-id":["S0074-02762026000105027"],"URL":"https:\/\/doi.org\/10.1590\/0074-02760250216","relation":{},"ISSN":["1678-8060","0074-0276"],"issn-type":[{"value":"1678-8060","type":"electronic"},{"value":"0074-0276","type":"print"}],"subject":[],"published":{"date-parts":[[2026]]},"article-number":"e250216"}}