Studies in healthy human T‐cell‐leukemia lymphoma virus (HTLV‐I) carriers from the Caribbean

Abstract

Six healthy relatives of 3 adult T‐cell leukemia lymphoma (ATLL) patients and 6 members of a Caribbean family immigrant to the UK have been investigated for the presence of HTLV‐I and expression of interleukin 2 (IL‐2) receptors. Serum antibodies to HTLV‐I were detected in all but 4 samples. Four to 10% of circulating cells from 3/4 seropositive donors studied displayed IL‐2 receptors (anti‐Tac+) and were shown to be convoluted lymphocytes by light microscopy morphology and immunoelectronmicroscopy. After 5 to 28 days in culture, cells from 4 seropositive donors reacted with monoclonal antibodies (MAbs) against the HTLV‐I core proteins, p19 and p24, and released retrovirus particles. Similar experiments with blood from 3 seronegative donors from the same families and 4 normal controls proved negative. Our findings indicate that seropositive individuals harbour the virus in a population of T‐lymphocytes which may then acquire receptors for IL‐2. These individuals are at risk of developing ATLL.