Neonates,elderly Persons,and Otherwise Immunocompromised Patients Are Particularly Susceptible to Infections

Multiple Choice

Neonates,elderly persons,and otherwise immunocompromised patients are particularly susceptible to infections with Listeria monocytogenes.These patients typically have fever and chills,often progressing to hypotension and septic shock.In healthy individuals,however,such intracellular microbes are usually effectively phagocytosed and killed by macrophages,which become activated via:

A) CD40L-CD40 interactions between activated T helper cells and macrophages
B) CD28-B7 interactions between activated T cells and macrophages
C) Fas ligand-Fas interactions between activated cytotoxic T lymphocytes and macrophages
D) TCR-MHC class II interactions between activated T helper cells and macrophages
E) LFA-1-ICAM-1 interactions between activated T cells and macrophages