A 43 year old man with chronic hepatitis B develops hepatocellular injury mediated by cytotoxic T lymphocytes. Liver biopsy shows hepatocytes undergoing apoptosis with condensed chromatin and intact membranes. Which of the following molecules released by CD8 positive T cells most directly triggers this process by entering target cells and activating caspases?

  1. A)Elastase
  2. B)Nitric oxide
  3. C)Histamine
  4. D)C5a
  5. E)Granzyme BGABARITO

Explicação

Cytotoxic T cells kill virus infected cells through perforin mediated pore formation and granzyme B entry into the target cell. Granzyme B activates caspases, producing apoptosis with cell shrinkage and limited inflammation, which fits the biopsy description. Ver explicação completa e trilha adaptativa →

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