Oral immunization with an attenuated vaccine strain of Salmonella typhimurium expressing the serine-rich Entamoeba histolytica protein induces an antiamebic immune response and protects gerbils from amebic liver abscess.
Attenuated salmonellae represent attractive candidates for the delivery of foreign antigens by oral vaccination. In this report, we describe the high-level expression of a recombinant fusion protein containing the serine-rich Entamoeba histolytica protein (SREHP), a protective antigen derived from virulent amebae, and a bacterially derived maltose-binding protein (MBP) in an attenuated strain of Salmonella typhimurium. Mice and gerbils immunized with S. typhimurium expressing SREHP-MBP produced mucosal immunoglobulin A antiamebic antibodies and serum immunoglobulin G antiamebic antibodies. Gerbils vaccinated with S typhimurium SREHP-MBP were protected against amebic liver abscess, the most common extraintestinal complication of amebiasis. Our findings indicate that the induction of mucosal and immune responses to the amebic SREHP antigen is dependent on the level of SREHP-MBP expression in S. typhimurium and establish that oral vaccination with SREHP can produce protective immunity to invasive amebiasis.
Zhang
T
T
Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Stanley
S L
SL
D000284:Administration, Oral; D000818:Animals; D000913:Antibodies, Protozoan / Q000096:biosynthesis / Q000097:blood; D000953:Antigens, Protozoan / Q000008:administration & dosage / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology; D002352:Carrier Proteins / Q000235:genetics / Q000276:immunology; D004748:Entamoeba histolytica / Q000235:genetics* / Q000276:immunology*; D005260:Female; D005849:Gerbillinae; D007070:Immunoglobulin A / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000097:blood; D008101:Liver Abscess, Amebic / Q000276:immunology / Q000517:prevention & control*; D058619:Maltose-Binding Proteins; D008565:Membrane Proteins / Q000235:genetics* / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009092:Mucous Membrane / Q000276:immunology; D015800:Protozoan Proteins / Q000235:genetics* / Q000276:immunology*; D016052:Protozoan Vaccines / Q000008:administration & dosage*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D012486:Salmonella typhimurium / Q000235:genetics* / Q000276:immunology*; D014613:Vaccines, Attenuated / Q000008:administration & dosage; D014614:Vaccines, Synthetic / Q000008:administration & dosage*
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D001426:Bacterial Proteins; D002352:Carrier Proteins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D058619:Maltose-Binding Proteins; D008565:Membrane Proteins; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D011993:Recombinant Fusion Proteins; D014613:Vaccines, Attenuated; D014614:Vaccines, Synthetic; C073020:serine-rich protein, Entamoeba histolytica