A monoclonal antibody to an antigen present in cells from a patient with Hodgkin's disease.

A monoclonal antibody-secreting hybridoma cell line, VCD-1, was derived from the fusion of murine myeloma cells with splenocytes from a BALB/c mouse that had been immunised with chronic B-lymphocytic leukaemia cells. The cells came from a patient who had developed the leukaemia approximately 10 years after a course of radiotherapy for nodular sclerosing Hodgkin's disease. The antibody bound to a 30,000-dalton protein that was present in normal and malignant B cells, in monocytes, neutrophils, and interdigitating reticulum cells, and in malignant cells present in Hodgkin's disease lymph nodes. The reactive epitope was not accessible to antibody in viable intact cells; binding to peripheral blood cells could only be seen if the cells were fixed. The antibody recognises a determinant that probably resides on the alpha-chain of HLA class II molecules.