PPD-induced viral antibody production in human blood lymphocytes

The ability of purified protein derivative of tuberculin (PPD) to induce polyclonal antibody production in cultures of human blood lymphocytes was studied. IgG and IgM were determined by the enzyme-linked immunosorbent assay (Elisa). PPD induced both IgM and IgG production, with a predominance of IgM. PPD usually stimulated a stronger IgM response but a weaker IgG response than did pokeweed mitogen (PWM). Supernatants of PPD- or PWM-stimulated lymphocyte cultures were tested for antibodies to morbilli, rubella and herpes simplex by Elisa. PPD as well as PWM induced viral antibody production in lymphocytes of donors who had serum antibodies to the corresponding viral antigens. Production of viral antibodies of IgG class but not of IgM class was demonstrated. The PPD-induced antibody response was T cell-dependent.