ANTIBODIES AGAINST DENGUE VIRUS-E PROTEIN PEPTIDE BIND TO HUMAN PLASMINOGEN AND INHIBIT PLASMIN ACTIVITY

Both mice and rabbits immunized with dengue virus E protein peptide sp anning amino acids 100-119 (D4E) produced antibodies that reacted not only with the D4E peptide itself but also with human plasminogen, as s hown by ELISA and Western blot. Sera from dengue virus-hyperimmunized mice and dengue patients also contained antibodies against D4E and pla sminogen. Furthermore, such sera all contained plasmin inhibitory acti vity. Using affinity-purified anti-D4E antibodies and free D4E peptide for competitive inhibition, we demonstrated that the inhibition of pl asmin activity was due to anti-D4E antibodies rather than other substa nces in the sera. Taken together, these results suggest dengue virus E protein amino acids 100-119 are a cross-reactive immunogenic region, and antibodies against this region may interfere with human fibrinolys is.