A human T cell line with an abnormal trisomy 2 karyotype established by coculture of peripheral lymphocytes with an HTLV-II-infected simian leukocyte cell line.

A new human T cell line with a chromosomal abnormality (47,XY,+2), designated AS-IIA, was established by coculturing peripheral blood leukocytes of a healthy adult male with a lethally irradiated human T lymphotropic virus type II (HTLV-II)-infected simian leukocyte cell line (Si-IIA). A polymerase chain reaction method showed that this interleukin-2 (IL-2)-dependent cell line possessed the HTLV-II provirus genome; the cells also reacted with HTLV-II-positive human sera, anti-HTLV-I/II p24, and anti-HTLV-II gp46 antibodies. AS-IIA cells expressed the suppressor/cytotoxic T cell markers CD3+, CD4-, CD8+, CD25+, and HLA-DR+, with later conversion to CD8-. These cells showed better proliferation than other human HTLV-II-infected cell lines with normal karyotypes, but were not transplantable into severe combined immunodeficiency mice. Virus production from AS-IIA was confirmed not only by electron microscopic examination, which revealed mature and immature type C virus particles, but also by the capacity of the line to immortalize human T cells. These results suggest that HTLV-II shows broad tropism for T cells including CD4+ or CD8+, and that not only Si-IIA, but also AS-IIA, are good sources of HTLV-II. The authors of the present study believe that AS-IIA may be a useful human T cell line for the investigation of HTLV-II in comparison with HTLV-I.