A 61-year-old man arrives at the emergency room after experiencing fever, chills, and a productive cough with thick, blood-tinged sputum for several days. His temperature is 38.8 degrees Celsius (102 degrees Fahrenheit), his blood pressure is 90/60 mm Hg, and his pulse rate is 110 beats per minute. On examination, the patient appears lethargic and ill. The right lung has bronchial breath sounds and crackles. Klebsiella pneumoniae grows in blood and sputum cultures. The bacteria are found to express a lipopolysaccharide on their outer membrane surface, which stimulates toll-like receptors in inflammatory cells. This, in turn, causes the IB inhibitor protein to degrade, which normally binds to a latent transcription factor found in the cytoplasm. Which of the following factors is most likely to be directly activated by the removal of this inhibitor protein?

Question

Quizplus · Accepted Answer

Eductional Objective: The transcription factor nuclear factor-kappa B (NF-B) plays an important role in the immune response to infection. NF-B is normally found in the cytoplasm in an inactive, latent state, bound to its inhibitor protein, IB. Extracellular substances, such as lipopolysaccharide, can set off a signal cascade that leads to the destruction of IB and the translocation of free NF-B to the nucleus.

A 61-Year-Old Man Arrives at the Emergency Room After Experiencing