Different Interferon Beta Preparations Induce the Same Qualitative Immune Response in Human Skin.

Interferon beta (IFN beta) is used as a first-line treatment for multiple sclerosis (MS) and is injected intramuscularly or subcutaneously (s.c.). The subcutaneous route is considered more immunogenic as it is associated with increased antidrug antibody-positive patients. The skin contains dendritic cells (DCs) and it is unclear whether these contribute to immunogenicity. To assess the effect of IFN beta on skin-resident cells, IFN beta was injected intradermally (i.d.) ex vivo using a human skin explant model or s.c. in vivo in MS patients. Ex vivo, intradermal IFN beta injections reduced migration and enhanced surface CD86 expression of dermal DCs, and an increased expression of HLA-DR+ was observed in skin biopsies taken after subcutaneous IFN beta injection (in vivo). In both models, IFN beta elevated the expression of several inflammatory cytokines when compared to the control biopsies. Our results show that 3 different IFN beta preparations, normalized in dose and injection site, induce similar immune responses, suggesting that the differences in immunogenicity are likely due to the route and frequency of administration.