In addition, positron emission tomography (PET) targeting a second-generation translocator protein TSPO (TSPO-PET), an innovative marker for in vivo imaging of microglial activity states, confirmed a significant attenuation of microglial activation in both primary and secondary progressive MS patients following anti-BCMA CAR-T cell therapy. This evidence concerns the gene TNFRSF17 and myeloid sarcoma.