A 29-year-old woman presents with recurrent lymphadenopathy and splenomegaly. Vital signs show BP 118/76, HR 88, RR 16, Temp 37.2°C, SpO2 98%. Laboratory evaluation reveals lymphocytosis with elevated LDH at 520 U/L; flow cytometry shows increased double-negative T cells. Genetic testing demonstrates a mutation affecting abnormal signaling through a cell surface death receptor. She denies fever or recent infections. Which receptor-ligand pair involved in lymphocyte apoptosis is most likely affected?
- A)Fas and Fas ligandGABARITO
- B)BCL2 and BAX
- C)CD28 and B7
- D)IL 2 receptor and IL 2
- E)Integrin and ICAM 1
Explicação
The extrinsic apoptotic pathway is mediated by death receptors such as Fas on target cells binding Fas ligand on activated immune cells. Failure of this pathway impairs deletion of autoreactive lymphocytes and can cause autoimmune lymphoproliferative syndromes... Ver explicação completa e trilha adaptativa →