This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Inflammation & Repair, Subject name: Pathology
The principle cell in granuloma 
Select and explain. 
A. Fibroblast, B. Epithelioid cell, C. Giant cell, D. Plasma cell
B: Epithelioid cell
Answer: B: Epithelioid cell 
Explanation: Ans. (b) Epithelioid cell(Ref: Anderson 10th ed pg 583)Macrophages (also known as histiocytes) are the cells that define a granulomaThe macrophages in granulomas are often referred to as "epithelioid"Epithelioid macrophages differ from ordinary macrophages in that they have elongated nuclei that often resemble the sole of a slipper or shoe.These changes are thought to be a consequence of "activation" of the macrophage by the offending antigen.