Dissection of seroreactivity against the tryptophan-rich motif of the feline immunodeficiency virus transmembrane glycoprotein.
Immunogenicity of the tryptophan-rich motif (TrpM) in the membrane-proximal ectodomain of the transmembrane (TM) glycoprotein of feline immunodeficiency virus (FIV) was investigated. Peptide 59, a peptide containing the TrpM of the TM of FIV, was covalently coupled to Qbeta phage virus-like particles (Qbeta-59) in the attempt to induce potent anti-TrpM B cell responses in cats. All Qbeta-59 immunized cats, but not cats that received a mixture of uncoupled Qbeta and peptide 59, developed antibodies that reacted with a same epitope in extensive binding and binding competition assays. The epitope recognized was composed of three amino acids, two of which are adjacent. However, Qbeta-59-immune sera failed to recognize whole FIV in all binding and neutralization assays performed. Furthermore, no reactivity against the TrpM was detected by screening sera from FIV-infected cats that had reacted with TM peptides, confirming that this epitope does not seem to be serologically functional in the FIV virion. The data suggest that TrpM may not be a suitable target for antiviral vaccine design.
Freer
Giulia
G
Department of Experimental Pathology, University of Pisa, I-56127 Pisa, Italy.
Giannecchini
Simone
S
Tissot
Alain
A
Bachmann
Martin F
MF
Rovero
Paolo
P
Serres
Pierre Francoise
PF
Bendinelli
Mauro
M
D020816:Amino Acid Motifs / Q000276:immunology; D000595:Amino Acid Sequence; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D001402:B-Lymphocytes / Q000276:immunology; D002415:Cats; D018604:Epitope Mapping; D018985:Epitopes, B-Lymphocyte / Q000276:immunology; D016181:Feline Acquired Immunodeficiency Syndrome / Q000276:immunology / Q000821:virology; D007114:Immunization; D016089:Immunodeficiency Virus, Feline / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000276:immunology*; D009500:Neutralization Tests; D010455:Peptides / Q000737:chemistry / Q000276:immunology; D014364:Tryptophan; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000276:immunology*; D014771:Virion
D000914:Antibodies, Viral; D018985:Epitopes, B-Lymphocyte; D008562:Membrane Glycoproteins; D010455:Peptides; D014759:Viral Envelope Proteins; D014364:Tryptophan