This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Lens), Subject name: Ophthalmology
[{'content': 'Lens antigen are? \nSelect and explain. \nA. Neoantigen, B. Sequestrated antigen, C. Altered antigen, D. Cross reacting antigen', 'role': 'user'}, {'content': 'Answer: B \nExplanation: ANSWER: (B) Sequestrated antigenREF: Ananthanarayan & Paniker 7th ed page 171, Textbook Of Medical Physiology ByKhurana 2009 ed page 207Hidden antigen or sequestrated antigen:Certain self antigens are present in the close system and never exposed to the immune system during fetal life. These are known as hidden antigen or sequestrated antigens. E.g.Sperm antigen, Lens proteins being enclosed in capsule', 'role': 'assistant'}]