Hemolytic Antibodies for Sheep and Ox Erythrocytes

Paul and Bunnell (1932) observed very high concentrations of agglutinins and hemolysins for sheep cells in the sera of patients during the acute stages of infectious mononucleosis, and this observation was found by these investigators to be of much value in the diagnosis of the disease. This finding has been confirmed and extended by Rosenthal and Wenkebach (1933), Boveri (1933), Bunnell (1933) and Bernstein (1934). In addition to the practical application in diagnosis, theoretical interest centers about the fact that antibodies for sheep cells are produced or enhanced in a disease of unknown etiology. Paul and Bunnell offered two explanations for their findings: (1) that the unknown agent responsible for infectious mononucleosis contains the heterophile or Forssman antigen; (2) that they were dealing with an example of isoagglutinin production elicited by abnormal cells, which are present either in the blood, or elsewhere, during active stages of the disease. In studies of infectious mononucleosis by different investigators, a probable bacterial origin has often been suggested, with special mention of the streptococcus group, diphtheroid bacilli, and Vincent's organisms, all of which have been found in nose, mouth or throat lesions during the disease. Nyfeldt (1929) has reported the isolation of a small V-shaped or curved gram positive organism from the blood, which he called Bacterium monocytogenes hominis, and with which he produced the cellular blood picture of infectious mononucleosis in rabbits. Agglutination of this organism in 1 to 250 dilution by the serum of the patient was observed, but only five days after the temperature had become normal. Gorham, Smith and Hunt (1929) claimed to have produced the typical blood picture of the disease in guinea pigs by inoculation of membrane from the pharynx of