Immunoaffinity purification of native dimer forms of the flavivirus non-structural glycoprotein, NS1

The flavivirus non-structural glycoprotein, NS1 has been shown to elicit an immune response in animals which may confer protection from subsequent virus challenge (Schlesinger et al., 1985 and 1987). While previous reports have outlined methods for obtaining cell-associated NS1 in monomeric form for these studies, we describe here an efficient method for the immunoaffinity purification of both cell-associated and secreted NS1 in their native dimeric configuration. These dimer preparations were shown to be both more antigenic and immunogenic than their monomeric counterparts, a finding which may in part explain the reported failure to obtain solid protection of mice from homologous dengue virus challenge. In moderately sized virus growth experiments, greater than 1 mg quantities of purified NS1 were obtained.