Percent distribution of T-and B-lymphoid cells in spleen and lymph nodes of Moloney virus infected mice.

Malignant lymphomas were induced in BALB/cAnN mice by infection with Moloney virus (MLS-6). During the latent period of lymphoma development T- and B-cell populations were quantitated in spleen and lymph nodes using fluorescein-labelled monospecific antisera. A progressive decrease in percent T- and B-cells was observed in these organs starting eight weeks post virus infection. It apparently precedes slightly the earliest significant pathologic lesions represented primarily by thymic atrophy. Malignant lymphomas which were diagnostic from the 12th week after virus inoculation are composed of immature lymphoid cells which were not shown to contain T-cell markers nor immunoglobulin receptors. It is questioned whether the shift in cell population in lymphoreticular tissues during the latent period of lymphoma development may correlate with functional disturbances of these tissues that may be virus-induced.