Application of Immunofluorescence to the Study of Human Leukemia

Abstract

The concentrated plasma of individuals with leukemia has been shown by several electron microscopists to contain virus-like particles. In the present study, plasmas containing similar particles were used as an antigen in the production of an antiserum in rabbits. After absorption with normal human antigens and labeling with fluorescein isothiocyanate, this serum reacted specifically with various cellular elements of the bone marrow and peripheral blood of a significant number of patients with leukemia, and failed to react with leukocytes of nonleukemic individuals. A similar antibody prepared against a murine leukemia virus (Rauscher) cross-reacted with the bone marrow and peripheral blood cells from some humans with leukemia, and especially with the cells from a patient with erythroleukemia. It is of interest that this murine leukemia resembles human erythroleukemia pathologically. Tissue culture cells of Burkitt's lymphoma reacted strongly with the antihuman leukemia fluorescent antibody, and less strongly with the antimurine. These same preparations of fluorescent antibody did not react with HeLa cells infected with either Herpes simplex or Herpes zoster viruses. These findings are interpreted as supporting the hypothesis of a viral etiology of human leukemia, and as suggesting a strong probability of antigenic similarities among strains of leukemia virus infecting various species.