Decreased integrin gene expression in patients with MS responding to interferon-β treatment

Interferon-β (IFN-β) ameliorates disease course in a subset of patients with MS. The reasons for heterogeneity of clinical responses, however, are unclear. We assessed possible effects of IFN-β on the gene expression of the leukocyte adhesion molecules VLA-4 and LFA-1 during the first year of treatment of 50 patients with relapsing–remitting MS who showed differential clinical responses. We observed a significant reduction of VLA-4 ( P=0.002) and LFA-1 ( P=0.03) mRNA expression compared to baseline in first-year clinical responders ( n=22). In contrast, first-year IFN-β non-responders ( n=28) had unchanged levels of VLA-4 and LFA-1. In vitro treatment of PBMC with IFN-β indicated a direct effect on transcription of the integrins' genes. Transcriptional downmodulation of adhesion molecules during IFN-β treatment may contribute to its mode of action in MS.