Impact of methotrexate and adalimumab on immune function of patients with psoriasis

Patients with psoriasis are commonly treated with methotrexate or biologics. We examined the immune response in a whole blood assay (TruCulture®) to assess the effect of methotrexate and adalimumab. Twenty patients with psoriasis were included and cytokine levels following stimulation with LPS, R848, HKCA, PolyIC, or a blank were investigated before and after 3-6 months of treatment with methotrexate or adalimumab and in patients who had received adalimumab >5 years. Methotrexate only induced minor changes in the cytokine responses, whereas adalimumab affected a wide range of cytokines important for the immune defense towards microorganisms. In the long-term adalimumab treated group, the cytokine levels were almost equivalent to the short-term adalimumab-treated group. Overall, methotrexate was not associated with cytokine suppression. Short and long-term treatment with adalimumab lowered multiple cytokines involved in the immune defense equally emphasizing the need to continuously be aware of the risk of infections in these patients.