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.
Department of Microbiology, Chosun University Medical School, Dong-Gu, Kwangju, South Korea. ylim@mail.chosun.ac.kr
Y
Y
Lim
S H
SH
Shin
I Y
IY
Jang
J H
JH
Rhee
I S
IS
Kim
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