U90

A brief report and discussion on the immunol. data observed in a series of individuals with or without chromosomally integrated human herpes virus 6 (ciHHV6) is given.U54-specific interferon-γ (IFN-γ)⁺ T cells were detectable in at least one sample from 11 out of 12 ciHHV6⁺ subjects.CD62L^- effector memory CD8⁺ T lymphocytes, specific to either U54 or U90, represented the prevalent circulating subsets in the ciHHV6⁺ group.Circulating T cells were able to secrete IL-10 after U54/U90 antigenic stimulation.These findings suggest that in ciHHV6⁺ individuals, HHV6-specific cytotoxic T-cell responses are significantly more reactive (i.e. more pronouncedly expandable) upon specific prolonged stimulation.Clinicoimmunol. monitoring should be set up to assess whether an enhanced cytotoxic immunity against HHV6 antigens is detectable in a significant concomitance with pathol. manifestations associated with ciHHV6.