Table 5 Manual evaluation of major histocompatibility complex class I antigen expression on the surface of muscle fibres, and membranolytic attack complex deposits in capillaries and in necrotic muscle fibres, and on the surface of non‐necrotic fibres.

Patients/diagnosis	MHC class I antigen			MAC
	Fibres			Capillaries			Fibres
	B.T.	After 24–48 h	After third inf	B.T.	After 24–48 h	After third inf	B.T.	After 24–48 h	After third inf
1/PM	+	–	+	+	+	++	+	–	–
2/PM	++++	+	++	+	+	+	++	++	+
3/PM	+	+	+	++	++	+	+++	+++	+
4/PM	+++++	+++++	NA	++	+++	NA	+	+	NA
5/PM	++++	++++	NA	++	+	NA	+++	+	NA
6/PM	–	+	+	++	++	+++	–	–	+
7/DM	+	+	+	+	+	+	+++	++	+
8/DM	+++++	++++	NA	+++	++	NA	–	+	NA
9/DM	+++	+++++	NA	++	++	NA	++	+	NA
10/DM	+	NA	+	+	NA	++	–	NA	++
11/JDM	+	NA	+	+	NA	+	–	NA	–
12/IBM	+++++	NA	+++++	+	NA	+	++	NA	++
13/IBM	+	+++	+++++	++	+++	+++	+	–	–

B.T., before treatment; DM, dermatomyositis; IBM, inclusion body myositis; Inf, infusion; JDM, juvenile onset dermatomyositis; NA, not available/assessable; PM, polymyositis.

Grading explanations are described in table 3. Individual changes after the third infusion: in major histocompatibility complex‐I, ⇔ 1–3, 6–7, 10–12 ⇑ 13; in membranolytic attack complex fibres, ⇔ 1–2, 6, 11–13 ⇓ 3, 7 ⇑ 10; in membranolytic attack complex capillaries, ⇔ all patients.