Characterization of Virus Neutralizing Antibodies in Human Serum and Nasal Secretions

Summary The virus neutralizing activity of human serum and nasal secretions was characterized by gel filtration with Sephadex G-200 and sucrose density gradient ultracentrifugation. The predominant antibody activity in serum was found in association with the 7 S γG-immunoglobulins and, to a lesser extent, with the γA-immunoglobulins. Neutralizing activity to some viruses was found also in the 19 S regions. The antiviral activity in normal nasal secretions was associated with the γA-immunoglobulins, the predominant immunoglobulin in these secretions. In some normals, and during respiratory infections, nasal secretions contained γA- and γG-immunoglobulins, both of which showed antiviral activity. It is concluded that γA-immunoglobulins carry significant antiviral activity in serum and in nasal secretions.