EXPRESSION OF COMPLEMENT RECEPTOR-2 (CR-2) ON HTLV-1-INFECTED LYMPHOCYTES AND TRANSFORMED-CELL LINES

The expression of complement receptor 2 (CR2) has been demonstrated in established HTLV-1-transformed cell lines and in 12 studied de novo i nfected peripheral blood lymphocytes cultures, using 2 HTLV-1 sources. The simultaneous detection of CR2 and HTLV-1 antigens in both co-cult ivated and supernatant-infected peripheral blood lymphocytes suggest t hat the increased CR2 expression is in tandem with the increasing HTLV -1 antigen expression. CR2 up-regulation seen during polyclonal activa tion is presumably in response to a viral protein, although a cellular factor has not been ruled out. Increasing CR2 expression during early infection suggests its possible involvement in selection or developme nt of subsequent transformation events. Variable levels of CR2 in immo rtalized cell lines argue against its obligate expression of function in the maintenance of the transformed state. The expression of CR2 in cellular activation of T cells may be stage restricted. This study als o expands the cellular distribution for CR2.