UNINTEGRATED 2-LONG TERMINAL REPEAT CIRCULAR HUMAN T-LYMPHOTROPIC VIRUS-DNA ACCUMULATION DURING CHRONIC HTLV INFECTION

Accumulation of unintegrated human T lymphotropic virus (HTLV) DNA was analyzed in long-term T cell lines infected with HTLV type I (HTLV-I) or type II (HTLV-II). By using a polymerase chain reaction-based assa y, amplified products of expected size were obtained in all of the HTL V-I-infected (n = 7) and HTLV-II-infected (n = 8) cell lines. The sign al intensities of the hybridizing band varied greatly among the cell l ines and did not correlate with HTLV p24(gag) antigen production. Furt her analysis of HTLV-I-infected clones demonstrated considerable varia bility in the unintegrated DNA accumulation, suggesting that either th e epigenetic status of the host cell or some environmental factor dete rmines the occurrence of unintegrated DNA. The presence of lower level s of unintegrated DNA in most of the HTLV-infected, long-term cell lin es presumably results in persistent noncytopathic infection.