This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Non professional antigen presenting cell is A/E ? 
Select and explain. 
A. Endothelial cell, B. Epidermal cell, C. Fibroblasts, D. Red blood cells
D: Red blood cells
Answer: D: Red blood cells 
Explanation: Ans. is 'd' i.e., Red blood cells Non-professional antigenpresenting cell A non-professional APC does not constitutively express the Major Histocompatibility Complex class II (MHC class II) proteins required for interaction with naive T cells; these are expressed only upon stimulation of the non? professional APC by ceain cytokines such as IFN-y. All nucleated cells express the Major Histocompatibility Complex class I necessary to be considered a nonprofessional APC. As erythrocytes do not have a nucleus, they are one of the few cells in the body that cannot display antigens.