A method for treating multiple sclerosis comprises applying peripheral blood from a patient or subject to an apheresis column loaded with a solid support comprising one or more binding reagents capable of specifically binding to a chemokine receptor, optionally the chemokine receptor CCR2, CCR6, CCR3, CCR5, CCR1, CXCR3 and/or CCR9 immobilized directly or indirectly on the support thus removing one or more chemokine receptor, optionally CCR2, CCR6, CCR3, CCR5, CCR1, CXCR3 and/or CCR9 expressing cells from the peripheral blood of the patient or subject. Various companion diagnostic methods and useful binding reagents are also described.