A patient with a bacterial infection has elevated levels of mannose-binding lectin. Which pathway of the complement system is likely activated in this patient? 

A 45-year-old male presents with lower back pain radiating down his left leg. He reports numbness and weakness in his left foot. MRI reveals a herniated disc at the L4-L5 level.  What is the most likely cause of his symptoms? 

Which glycoprotein on the platelet membrane is crucial for platelet adhesion to the damaged vessel wall? 

What is the impact of immunosenescence on cancer risk in older adults? 

A 76-year-old man with Parkinson disease is evaluated for Pisa syndrome. He leans significantly to one side when walking. What additional symptom is likely to be contributing? 

A patient with an autoimmune disease has a deficiency in Tregs. What is the role of Tregs in the immune system?

A 22-year-old female basketball player presents with knee pain and swelling after landing awkwardly from a jump. She reports hearing a “pop” at the time of injury. Physical examination reveals a positive Lachman test.  What is the most likely diagnosis? 

A patient with an infection has elevated levels of cytokines in their blood. What is the role of these cytokines in acute inflammation? 

A 70-year-old male with a history of chronic inflammatory conditions presents with new-onset fatigue and weight loss. Laboratory tests reveal elevated inflammatory markers and abnormal white blood cell counts.  What is the most likely explanation for his increased cancer risk? 

A 70-year-old female’s cells are found to have entered replicative senescence.  What is the significance of this state?