Dengue is a serious cause of morbidity and mortality in tropical areas worldwide. We cloned and expressed recombinant polypeptides spanning the entire genome of a Brazilian dengue virus type 2 (DENV-2) strain in contiguous segments to generate antigens for dengue diagnosis and evaluation of the human humoral immune response. When analyzed by Western blot and an enzyme-linked immunosorbent assay (ELISA) using human sera, the most reactive polypeptide (pD2-3(E)) was located in the N-terminal portion of the envelope protein. The sensitivity of an IgG-ELISA using pD2-3(E) versus mouse brain antigen was 100% with convalescent sera and 79% with acute sera, with a specificity of 100%. Sera from patients infected with other DENV serotypes recognized pD2-3(E) equally well, whereas sera positive for yellow fever, rubella, and measles showed little or no reactivity. Using this novel approach, we identified a candidate antigen to facilitate diagnosis of DENV infections and observed a surprising variability in antibody patterns in the clinical response to DENV infections.
dos Santos FB, Miagostovich MP, Nogueira RM, Schatzmayr HG, Riley LW, Harris E. (2004). Analysis of recombinant dengue virus polypeptides for dengue diagnosis and evaluation of the humoral immune response. The American journal of tropical medicine and hygiene, 71(2)