Inflammation and Immune Pathology USMLE Step 1 Practice Question
A 28-year-old woman with systemic sclerosis presents with severe Raynaud's phenomenon, finger ulceration, and progressive skin tightening. Vital signs: BP 142/88, HR 98, RR 16, Temp 37.2°C, SpO2 98%. Serum creatinine is normal. Skin biopsy shows dense dermal fibrosis with adipose tissue replacement and increased collagen deposition. Which cytokine primarily mediates this excessive fibroblast activation and pathologic collagen synthesis in systemic sclerosis?
Answer choices
- ATumor necrosis factor-α
- BInterferon-γ
- CTransforming growth factor-βCorrect answer
- DInterleukin-6 alone
- EInterleukin-2
- FPlatelet-derived growth factor
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