Surface antibodies of human myelogenous leukaemia leukocytes reactive with specific type-C viral reverse transcriptases. 
Purified immunoglobin G (IgG) from patients with chronic myelogenous leukaemia specifically neutralised RT from feline leukaemia virus while purified IgG from other types of leukaemias and from normal blood cells were less reactive and in some cases preferentially reacted with RT from horizontally transmitted primate type-C viruses (simian sarcoma virus-gibbon ape leukaemia virus group).  This indicates the presence of a heterogeneous immune response to RT or to an RT-like molecule in humans.