Lymphadenopathy driven by TCR-Vγ8Vδ1 T-cell expansion in FAS-related autoimmune lymphoproliferative syndrome

FAS-dependent apoptosis in Vδ1 T cells makes the latter possible culprits for the lymphadenopathy observed in patients with FAS mutations.Rapamycin and methylprednisolone resistance should prompt clinicians to look for Vδ1 T cell proliferation in ALPS-FAS patients.