Hc. Wu et al., Identification of B-cell epitope of dengue virus type 1 and its application in diagnosis of patients, J CLIN MICR, 39(3), 2001, pp. 977-982
Using a serotype-specific monoclonal antibody (MAb) of dengue virus type 1
(DEN-1), 15F3-1, we identified the B-cell epitope of DEN-1 from a random pe
ptide library displayed on phage, Fourteen immunopositive phage clones that
bound specifically to MAb 15F3-1 were selected, These phage-borne peptides
had a consensus motif of HxYaWb (a = S/T, b = K/H/R) that mimicked the seq
uence HKYSWK, which corresponded to amino acid residues 111 to 116 of the n
onstructural protein 1 (NS1) of DEN-1, Among the four synthetic peptides co
rresponding to amino acid residues 110 to 117 of the NS1 of DEN-1, -2, -3,
and -4, only one peptide, EHKYSWKS (P14M) of DEN-1, was found to bind to 15
F3-1 specifically. Furthermore, P14M was shown to inhibit the binding of ph
age particles to 15F3-1 in a competitive inhibition assay. Histidine(111) (
His(111)) was crucial to the binding of P14M to 15F3-1, since its binding a
ctivity dramatically reduced when it changed to leucine(111) (Leu(111)). Th
is epitope-based peptide demonstrated its clinical diagnostic potential whe
n it reacted with a high degree of specificity with serum samples obtained
from both DEN-l-infected rabbits and patients. Based on these observations,
our DEN-1 epitope-based serologic test could be useful in laboratory viral
diagnosis and in understanding the pathogenesis of DEN-1.