Are HIV-specific CTL responses salutary or pathogenic?

Recently, HIV has been shown to be highly variable in patients; it is capable of escaping, or even turning off, cytotoxic T-cell responses by mutating T-cell epitopes. New antiviral drugs have revealed the enormous turnover of C4+ T cells in infected patients, but have also shown how efficiently HIV rapidly escapes such treatments. Although HIV is usually considered to be cytopathic, this is not really known. The proposal that AIDS pathogenesis reflects immunopathological consequences of anti-HIV protective CD8+ T cells has to be seriously considered. Such a pathogenesis is illustrated by CD8+ T cell mediated immunosuppression during acute infection of mice with the non-cytopathic lymphocytic choriomeningitis virus.