AN EXPRESSION OF ANAPLASTIC LARGE-CELL LYMPHOMA-ASSOCIATED ANTIGENS ON HTLV-I-INFECTED CD4(-CELLS() T)

We investigated tumor-associated antigens induced by infection with hu man T-lymphotropic virus type I(HTLV-I). Anaplastic large cell lymphom a (APLL) antigens were found to be expressed on interleukin 2 (IL-2)-d ependent, HTLV-I-infected CD4(+) T-cell lines established from patient s with adult T-cell leukemia and HTLV-I-associated myelopathy/tropical spastic paraparesis. However, APLL antigens were not detected on unst imulated lymphocytes, mitogen-activated T lymphocytes, or Epstein-Barr virus-infected B cells. Furthermore, APLL antigens were not found on IL-2-independent HTLV-I-transformed cells such as MT-1 or MT-2. When n aive CD4(+) T cells were infected with HTLV-I in vitro in the presence of IL-2, the APLL antigens were detected on them 4 weeks after infect ion. The expression level increased in a time-dependent fashion. These results indicate that HTLV-I infection induces a unique category of t umor-associated antigens on CD4(+) T cells.