1 Department of Virus Diseases, Walter Reed Army Institute of Research and Department of Pediatrics, Georgetown University Medical Center, Washington, D.C.
Studies of antibody function in three patients with ataxia-telangiectasia are presented. Absence of serum
A-immunoglobulins was found in two of the patients; the third had normal amounts of this immunoglobulin. Nasal secretions of all three possessed
G- and
M-immunoglobulins; in 2 of 3 patients a variant immunoglobulin, not clearly
A, was detected in nasal secretions. Following fractionation of their sera by gel filtration with Sephadex G-200, neutralizing antibody to poliovirus 1, influenza A2/63, parainfluenza 3, and echovirus 28 were found in association with the
M- and
G-immunoglobulins in two patients and with all three immunoglobulins in the third. The pattern of neutralizing antibody in nasal secretions paralleled that of serum. Since the nasal secretions lacked or were markedly deficient in
A-immunoglobulins, the specific viral antibody detected therein was attributed to the increased concentrations of
M- and
G-immunoglobulins found. The data suggest that although patients with ataxiatelangiectasia lack the normal complement of
A-immunoglobulins in nasal secretions, they do contain antiviral antibody, but in association with other immunoglobulins.