Characterisation of the native lipid moiety of Echinococcus granulosus antigen B.
Antigen B (EgAgB) is the most abundant and immunogenic antigen produced by the larval stage (metacestode) of Echinococcus granulosus. It is a lipoprotein, the structure and function of which have not been completely elucidated. EgAgB apolipoprotein components have been well characterised; they share...
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ftdoajarticles:oai:doaj.org/article:18a9ceeaf1a14b3b94101f292940b95b 2023-05-15T15:14:13+02:00 Characterisation of the native lipid moiety of Echinococcus granulosus antigen B. Gonzalo Obal Ana Lía Ramos Valeria Silva Analía Lima Carlos Batthyany María Inés Bessio Fernando Ferreira Gustavo Salinas Ana María Ferreira 2012-01-01T00:00:00Z https://doi.org/10.1371/journal.pntd.0001642 https://doaj.org/article/18a9ceeaf1a14b3b94101f292940b95b EN eng Public Library of Science (PLoS) http://europepmc.org/articles/PMC3352830?pdf=render https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 doi:10.1371/journal.pntd.0001642 1935-2727 1935-2735 https://doaj.org/article/18a9ceeaf1a14b3b94101f292940b95b PLoS Neglected Tropical Diseases, Vol 6, Iss 5, p e1642 (2012) Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 article 2012 ftdoajarticles https://doi.org/10.1371/journal.pntd.0001642 2022-12-31T03:39:41Z Antigen B (EgAgB) is the most abundant and immunogenic antigen produced by the larval stage (metacestode) of Echinococcus granulosus. It is a lipoprotein, the structure and function of which have not been completely elucidated. EgAgB apolipoprotein components have been well characterised; they share homology with a group of hydrophobic ligand binding proteins (HLBPs) present exclusively in cestode organisms, and consist of different isoforms of 8-kDa proteins encoded by a polymorphic multigene family comprising five subfamilies (EgAgB1 to EgAgB5). In vitro studies have shown that EgAgB apolipoproteins are capable of binding fatty acids. However, the identity of the native lipid components of EgAgB remains unknown. The present work was aimed at characterising the lipid ligands bound to EgAgB in vivo. EgAgB was purified to homogeneity from hydatid cyst fluid and its lipid fraction was extracted using chloroform∶methanol mixtures. This fraction constituted approximately 40-50% of EgAgB total mass. High-performance thin layer chromatography revealed that the native lipid moiety of EgAgB consists of a variety of neutral (mainly triacylglycerides, sterols and sterol esters) and polar (mainly phosphatidylcholine) lipids. Gas-liquid chromatography analysis showed that 16∶0, 18∶0 and 18∶1(n-9) are the most abundant fatty acids in EgAgB. Furthermore, size exclusion chromatography coupled to light scattering demonstrated that EgAgB comprises a population of particles heterogeneous in size, with an average molecular mass of 229 kDa. Our results provide the first direct evidence of the nature of the hydrophobic ligands bound to EgAgB in vivo and indicate that the structure and composition of EgAgB lipoprotein particles are more complex than previously thought, resembling high density plasma lipoproteins. Results are discussed considering what is known on lipid metabolism in cestodes, and taken into account the Echinococcus spp. genomic information regarding both lipid metabolism and the EgAgB gene family. Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic PLoS Neglected Tropical Diseases 6 5 e1642 |
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Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
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language |
English |
topic |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
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Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 Gonzalo Obal Ana Lía Ramos Valeria Silva Analía Lima Carlos Batthyany María Inés Bessio Fernando Ferreira Gustavo Salinas Ana María Ferreira Characterisation of the native lipid moiety of Echinococcus granulosus antigen B. |
topic_facet |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
description |
Antigen B (EgAgB) is the most abundant and immunogenic antigen produced by the larval stage (metacestode) of Echinococcus granulosus. It is a lipoprotein, the structure and function of which have not been completely elucidated. EgAgB apolipoprotein components have been well characterised; they share homology with a group of hydrophobic ligand binding proteins (HLBPs) present exclusively in cestode organisms, and consist of different isoforms of 8-kDa proteins encoded by a polymorphic multigene family comprising five subfamilies (EgAgB1 to EgAgB5). In vitro studies have shown that EgAgB apolipoproteins are capable of binding fatty acids. However, the identity of the native lipid components of EgAgB remains unknown. The present work was aimed at characterising the lipid ligands bound to EgAgB in vivo. EgAgB was purified to homogeneity from hydatid cyst fluid and its lipid fraction was extracted using chloroform∶methanol mixtures. This fraction constituted approximately 40-50% of EgAgB total mass. High-performance thin layer chromatography revealed that the native lipid moiety of EgAgB consists of a variety of neutral (mainly triacylglycerides, sterols and sterol esters) and polar (mainly phosphatidylcholine) lipids. Gas-liquid chromatography analysis showed that 16∶0, 18∶0 and 18∶1(n-9) are the most abundant fatty acids in EgAgB. Furthermore, size exclusion chromatography coupled to light scattering demonstrated that EgAgB comprises a population of particles heterogeneous in size, with an average molecular mass of 229 kDa. Our results provide the first direct evidence of the nature of the hydrophobic ligands bound to EgAgB in vivo and indicate that the structure and composition of EgAgB lipoprotein particles are more complex than previously thought, resembling high density plasma lipoproteins. Results are discussed considering what is known on lipid metabolism in cestodes, and taken into account the Echinococcus spp. genomic information regarding both lipid metabolism and the EgAgB gene family. |
format |
Article in Journal/Newspaper |
author |
Gonzalo Obal Ana Lía Ramos Valeria Silva Analía Lima Carlos Batthyany María Inés Bessio Fernando Ferreira Gustavo Salinas Ana María Ferreira |
author_facet |
Gonzalo Obal Ana Lía Ramos Valeria Silva Analía Lima Carlos Batthyany María Inés Bessio Fernando Ferreira Gustavo Salinas Ana María Ferreira |
author_sort |
Gonzalo Obal |
title |
Characterisation of the native lipid moiety of Echinococcus granulosus antigen B. |
title_short |
Characterisation of the native lipid moiety of Echinococcus granulosus antigen B. |
title_full |
Characterisation of the native lipid moiety of Echinococcus granulosus antigen B. |
title_fullStr |
Characterisation of the native lipid moiety of Echinococcus granulosus antigen B. |
title_full_unstemmed |
Characterisation of the native lipid moiety of Echinococcus granulosus antigen B. |
title_sort |
characterisation of the native lipid moiety of echinococcus granulosus antigen b. |
publisher |
Public Library of Science (PLoS) |
publishDate |
2012 |
url |
https://doi.org/10.1371/journal.pntd.0001642 https://doaj.org/article/18a9ceeaf1a14b3b94101f292940b95b |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
PLoS Neglected Tropical Diseases, Vol 6, Iss 5, p e1642 (2012) |
op_relation |
http://europepmc.org/articles/PMC3352830?pdf=render https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 doi:10.1371/journal.pntd.0001642 1935-2727 1935-2735 https://doaj.org/article/18a9ceeaf1a14b3b94101f292940b95b |
op_doi |
https://doi.org/10.1371/journal.pntd.0001642 |
container_title |
PLoS Neglected Tropical Diseases |
container_volume |
6 |
container_issue |
5 |
container_start_page |
e1642 |
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1766344691395067904 |