Serum-derived IgG1-mediated immune exclusion as a mechanism of protection against H. pylori infection.
The induction of protective immunity against Helicobacter challenge in a murine model was found to correlate with the magnitude of IgG (serum and gastric lavage) responsiveness to intra-nasal (i.n.) immunisation. IgG1-secreting hybridoma backpacks in Helicobacter pylori (H. pylori)-infected mice revealed serum transudation into the stomach. A Lpp20-specific monoclonal antibody was associated with significantly reduced H. pylori colonisation. Histology revealed aggregates of the remaining H. pylori in these mice, suggesting a role for IgG1-mediated immune exclusion of the bacteria. In vitro immunogold electron microscopy supported this hypothesis, but also suggested that a threshold of H. pylori-specific antibody needs to be maintained if immune exclusion by the host is to overcome immune evasion by the bacteria.
Keenan
Jacqueline
J
Department of Surgery, Christchurch School of Medicine, P.O. Box 4345, Christchurch, New Zealand. jacqui.keenan@chmeds.ac.nz
Neal
Stephanie
S
Allardyce
Randall
R
Roake
Justin
J
D000281:Administration, Intranasal; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D000942:Antigens, Bacterial; D001428:Bacterial Vaccines / Q000008:administration & dosage; D005260:Female; D016481:Helicobacter Infections / Q000276:immunology* / Q000517:prevention & control*; D016480:Helicobacter pylori / Q000276:immunology*; D006825:Hybridomas / Q000276:immunology; D007116:Immunization, Passive; D007074:Immunoglobulin G / Q000097:blood*; D051379:Mice; D008807:Mice, Inbred BALB C; D016253:Microscopy, Immunoelectron; D013270:Stomach / Q000276:immunology / Q000382:microbiology
D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; D007074:Immunoglobulin G