To address this question, we quantified plasma levels of ADAs, TNF-α, sTNFRI and sTNFRII, examined the functional capacity of PBMCs to respond to lipopolysaccharide (LPS), and characterized the main populations of monocytes in a large cohort of patients with psoriasis treated with different biological drugs (anti-TNF), including responders and non-responders to treatment. Here, TNF is linked to psoriasis.