Human Helper T Cell Lines Established by Coculture of Normal Human Cord Leukocytes with an HTLV‐Il‐infected Rabbit Leukocyte Cell Line (Ra‐IIA)

Abstract

Three helper T cell lines, designated CR ‐IIA (CR‐IIA‐1, CR‐IIA‐ 2, and CR‐IIA‐3), were established by coculturing nor mal human cord leukocytes with a lethally irradiated HTLV II (human T lymphotropic virus type II)‐ infected rabbit leukocyte cell line (Ra‐IIA). CR IIA had a normal human karyotype and expressed the surface markers CD3(+), CD4(+), CD8(‐), CD19(‐), CD25(+) and HLA‐ DR(+), confirming their helper T cell nature. CR‐ IIA cells were all free of Epstein‐ Barr virus nuclear antigen and were im‐muno reactive with serum samples from HTLV‐ I‐ or HTLV‐Il‐ infected patients and with anti HTLV‐ I, p19 or p24 anti body. The provirus genome of HTLV‐II was detected in these cell lines by the polymerase chain reaction combined with a digoxigenin‐ enzyme‐ linked immunosorbent assay. Electron microscopy of CR‐IIA‐1 cells revealed a few im mature type C virus particles. These results suggest that HTLV‐ II was transmitted from the infected rabbit leukocyte cell line to human cord helper T lymphocytes with the development of immortalized HTLV ‐ II‐ producing T cell lines. Acta Pathol Jpn 42: 347–352, 1992.