Table 4.

MS drugs potentially effecting HERV expression.

Drug	Example	Drug's principal mode of action	Action against HERVs
Immunomodulatory agents	Interferon-β	Decreases leukocyte transmigration; antiviral;	Reduces HERV-W env RNA load, anti-HERV-W and HERV-H antibodies in sera; regulates syncytin promoter
Anti-psychotics			Reduction in intensity, density and compound value of HERV-W gag interneurons in alveus of patients with schizophrenia (Weiss et al., 2007)
Antiviral	Foscarnet	Inhibits reverse transcriptase	Blocks endogenous retrovirus (Sundquist and Oberg, 1979)