Fig. 5.

Macrophage-rich infiltrates with B cell/plasma cell clusters are characteristic for ASyS-associated myositis. Representative immunohistochemical stains of muscle biopsies from anti-Jo-1⁺ (n = 10), PL-7⁺ (n = 6) and PL-12⁺ (n = 8) patients for CD68, CD8, CD20 and CD138 (a). Scale bar 100 µm. Prominent invasion by CD68⁺ macrophages and T cells into the perimysium and the adjacent endomysial areas was observed. Muscle morphology was quantified and compared between subgroups by semi-quantitative score. Representative muscle biopsies are displayed (d) for C5b-9, MHC-cl. I and MHC-cl. II for serological subgroups. Scale bar 100 µm. Differences between groups were analyzed using the Kruskal–Wallis test followed by Bonferroni-Dunn correction for multiple comparisons. The level of significance was set to p < 0.05. *p < 0.05. ASyS Anti-synthetase syndrome, NDC non-diseased control