Figure 2 (A) Major histocompatibility complex class I antigen expression on the muscle fibre membrane and sarcoplasma of the muscle fibres (brown staining) before intravenous immunoglobulin (IVIG) treatment remained unchanged in the repeat biopsies (patient 12, inclusion body myositis). (B) Membranolytic attack complex (MAC) deposits in the capillaries (arrows, brown staining) before IVIG treatment remained unchanged in the repeat biopsies (patient 6, polymyositis). (C) Intercellular adhesion molecule‐1 (ICAM‐1) expression in capillaries (arrow, red staining) and inflammatory cells remained unchanged in the repeat biopsies (patient 9, dermatomyositis). Scale bar = 50 μm (original magnification ×250).