DNA and RNA Synthesis in Cultures of Peripheral Blood Mononuclear Leucocytes from Normal and Lymphosarcomatous Cows

SUMMARY DNA and RNA synthesis was studied in bovine blood mononuclear leucocytes cultured with and without PHA. Two of seven lymphosarcomatous cows showed a higher rate of spontaneous (i.e. without PHA) DNA and RNA synthesis, but one of these two showed no increase in DNA synthesis and a decrease in RNA synthesis in cultures with PHA. These two cows also had a large number of lymphoblasts in their peripheral blood in contrast to the other lymphosarcomatous cows and which did not show significantly different patterns of DNA and RNA synthesis from normal cows in cultures either with or without PHA, although some of the lymphosarcomatous cows had atypical lymphocytes and increased lymphocyte counts. Only in the two cows which had many lymphoblasts and a higher rate of spontaneous DNA and RNA synthesis, were there many dividing cells with abnormal chromosome complements.