Langford et al. reported increased P-gp immunoreactivity in glial cells in brain autopsy tissues from patients with HIV-encephalitis (HIVE), [10] whereas, Persidsky et al. reported a decreased P-gp expression in tissues obtained from HIVE patients and from the severe combined immunodeficiency (SCID) mice model of HIVE [11]. This evidence concerns the gene PGP and viral encephalitis.