TRAIL, CXCL10 and CCL2 plasma levels during long-term Interferon-β treatment of patients with multiple sclerosis correlate with flu-like adverse effects but do not predict therapeutic response

High serum levels of soluble TRAIL (sTRAIL) before or during the first year of Interferon-β (IFN-β) therapy were shown to predict an individual therapeutic response of patients with relapsing–remitting multiple sclerosis (RRMS). Here, we investigated whether sTRAIL plasma levels during long-term IFN-β treatment correlate with future therapeutic response or adverse effects of treatment. Postinjection short-time bursts of sTRAIL were associated with flu-like symptoms and IP-10/CXCL10 as well as MCP-1/CCL2 induction, and were detected after up to 6 years of continuous IFN-β therapy. However, neither sTRAIL nor chemokine levels allowed prediction of one- and two-year clinical treatment response in 30 RRMS patients, prospectively followed by blinded investigators.