An antigen in Hodgkin's disease tissue cultures: fluorescent antibody studies

Rabbits were immunized with an antigen of specific gravity, 1.15-1.21 isolated by density gradient sedimentation of the centrifuged medium of long-term monolayer cultures derived from spleens involved by Hodgkin's disease. The globulin fraction of the antiserum was absorbed to reduce reactivity with normal cellular antigens and tissue culture components, and was tested by the indirect fluorescent antibody technique with cells from 18 different Hodgkin's disease cultures, and 16 normal cultures derived from adult spleen and fetal spleen and thymus. With anti-Hodgkin's disease globulin diluted 1:40 and 1:80, positive surface staining was observed in 48% and 41%, respectively, of viable cells from Hodgkin's disease cultures, and in less than 5% of cells cells from normal cultures. Fluorescent staining of the cytoplasm without nuclear staining was observed in 51% of acetone-fixed cells from the Hodgkin's disease cultures and in 4-8% of cells from normal cultures. Reactivity of the antiserum with Hodgkin's disease target cells could be removed by absorption of the antibody with additional antigen of density 1.15-1.21 obtained from other Hodgkin's disease cultures. Antisera to fractionated medium from a normal spleen culture and to noncultured Hodgkin's disease tumor tissue were used as controls: 2-10% of viable and acetone-fixed target cells reacted and no difference was observed between Hodgkin's disease and normal cell cultures. In vitro propagation of tumor cells from patients with Hodgkin's disease is needed for detection of the Hodgkin's disease tissue culture antigen; the antigen could not be demonstrated in noncultured Hodgkin's disease tissue.