View article

Cytokines, chemokines and soluble adhesion molecules interact in a complex network within the immune system. Fingerprinting of these proteins may allow the use of these proteins as biomarkers for identification of disease, disease subtyping and monitoring therapeutic interventions. We developed a multiplex immunoassay (MIA) for the detection of 30 proteins in a variety of human body fluids such as plasma and synovial fuid (SF). The measurement of these proteins is hampered by the presence of human (auto-) antibodies, which can cause non-specific binding. We have validated a novel approach for the removal of interfering immunoglobulins using pre-absorption with protein-L. Interfering (auto-) antibodies, such as rheumatoid factor (RF), were removed using three methods; polyethylene glycol (PEG) precipitation, pre-absorption with human γ-globulin or pre-absorption with protein-L. A significant decrease …