Using unexposed individuals to establish a positivity cut-off (Figure S1), cytokine release above threshold was observed in 79.1% (IFNγ+), 95.3% (IL-2+), and 86.0% (IFNγ+/IL-2+) of aCD20-MS individuals, compared to 52.9%, 91.2%, and 73.5% in the control cohort. Here, IFNG is linked to myeloid sarcoma.