title: Immunization with a tetramer derivative of an anti-inflammatory pentapeptide produced by Entamoeba histolytica protects gerbils (Meriones unguiculatus) against experimental amoebic abscess of the liver.
abstract: Axenically grown Entamoeba histolytica produces a pentapeptide (Met-Gln-Cys-Asn-Ser) with several anti-inflammatory properties, including the inhibition of human monocyte locomotion (Monocyte Locomotion Inhibitory Factor (MLIF)). A construct displays the same effects as the native material. It remains to be seen if MLIF is used, or even produced in vivo by the tissue-invading parasite. If MLIF were to be relevant in invasive amoebiasis, immunizing against it could diminish this parasite advantage and prevent lesions. KLH-linked MLIF mixed with Freund's adjuvant was too aggressive an immunizing material to answer this question. However, immunization with a tetramer of MLIF (but not a scrambled version of MLIF) around a lysine core (MLIF-MAPS), that displays increased antigenicity, yet lacks excessive innate immunity activation, completely protects gerbils against amoebic abscess of the liver caused by the intraportal injection of virulent E. histolytica. Liver abscesses caused by Listeria monocytogenes were not prevented. Invasive E. histolytica may produce the parent protein of MLIF in vivo, and if appropriately cleaved, it may play a role in invasive amoebiasis. MLIF may join new vaccination strategies against amoebiasis.
authors.affiliation: Unidad de Investigación Médica en Inmunología, Hospital de Pediatría, Coordinacion de Investigacion en Salud, Centro Medico Nacional, Siglo XXI, IMSS. Mexico, D.F., Mexico.
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: Giménez-Scherer
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Cárdenas
authors.forename: Martha
authors.initials: M
authors.lastname: López-Osuna
authors.forename: Juan Raymundo
authors.initials: JR
authors.lastname: Velázquez
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Rico
authors.forename: Armando
authors.initials: A
authors.lastname: Isibasi
authors.forename: María del Carmen
authors.initials: Mdel C
authors.lastname: Maldonado
authors.forename: María Esther
authors.initials: ME
authors.lastname: Morales
authors.forename: Jorge
authors.initials: J
authors.lastname: Fernández-Diez
authors.forename: Roberto R
authors.initials: RR
authors.lastname: Kretschmer
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000276:immunology* / Q000494:pharmacology; D004748:Entamoeba histolytica / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005849:Gerbillinae; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007114:Immunization / Q000379:methods*; D007074:Immunoglobulin G / Q000097:blood; D008101:Liver Abscess, Amebic / Q000276:immunology* / Q000517:prevention & control*; D008213:Lymphocyte Activation / Q000276:immunology; D008214:Lymphocytes / Q000166:cytology / Q000276:immunology; D008297:Male; D009842:Oligopeptides / Q000276:immunology* / Q000494:pharmacology; D010455:Peptides / Q000276:immunology; D011897:Random Allocation
chemical_list: D000893:Anti-Inflammatory Agents; D007074:Immunoglobulin G; D009842:Oligopeptides; D010455:Peptides; C430647:monocyte locomotion inhibitory factor