Immune complexes (ICs) have been detected in patients’ sera with JIA utilizing a variety of methods, including the anti-human IgM affinity column, C1q solid-phase assay, polyethylene glycol precipitation, Staphylococcal Protein A separation method, anti-C1q/C3 affinity columns, and FcγRIII affinity method. The gene discussed is CD40LG; the disease is juvenile idiopathic arthritis.