A human transferrin-binding protein of Staphylococcus aureus is immunogenic in vivo and has an epitope in common with human transferrin receptor.
To understand human immune responses against the human transferrin-binding protein of Staphylococcus aureus (SA-tbp), we examined cell wall proteins from S. aureus ATCC 6538 using human convalescent sera, and a monoclonal antibody specific for human transferrin receptor (McAb-HTR). The SA-tbp, detected by immunoblot assay, was iron-repressible, reacted with the convalescent sera, and cross-reacted with McAb-HTR. Immunoelectron microscopy probed with McAb-HTR showed a reaction zone around the test strain from the deferrated BHI. After being preincubated with an S. aureus-bacteremic serum, the electroblot of the SA-tbp still reacted with McAb-HTR, but not with human transferrin-horseradish peroxidase conjugate. We conclude, there are at least two kinds of epitopes in the SA-tbp; one able to bind to human transferrin is immunogenic in humans, but the other sharing epitopes common with human transferrin receptor is not immunogenic in humans.
Lim
Y
Y
Department of Microbiology, Chosun University Medical School, Dong-Gu, Kwangju, South Korea. ylim@mail.chosun.ac.kr
Shin
S H
SH
Jang
I Y
IY
Rhee
J H
JH
Kim
I S
IS
D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D000942:Antigens, Bacterial / Q000276:immunology*; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology* / Q000378:metabolism; D002352:Carrier Proteins / Q000276:immunology* / Q000378:metabolism; D002473:Cell Wall / Q000276:immunology; D003429:Cross Reactions; D000939:Epitopes; D006801:Humans; D015151:Immunoblotting; D033862:Iron-Binding Proteins; D016253:Microscopy, Immunoelectron; D011990:Receptors, Transferrin / Q000276:immunology*; D013203:Staphylococcal Infections / Q000276:immunology; D013211:Staphylococcus aureus / Q000235:genetics / Q000276:immunology*; D014168:Transferrin / Q000378:metabolism*; D033863:Transferrin-Binding Proteins
D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; D000939:Epitopes; D033862:Iron-Binding Proteins; D011990:Receptors, Transferrin; D014168:Transferrin; D033863:Transferrin-Binding Proteins