Following further dimensionality reduction of isolated T-cell populations, five distinct T-cell subsets were identified (Figure S9C) with their representative marker genes for each subset shown in Figure S9D. Compared to the HC group, the MMD group exhibited a significant increase in CD4+ T-cell subsets and a significant decrease in CD8+ T-cell subsets, with no significant differences observed in the proportions of the remaining subsets (Figure S9E). Here, CD4 is linked to multiminicore myopathy.