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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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CD4 lymphocytes (helper cells) recognize -
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The correct answer is  Class II MHC antigens have single locus as HLA-D. - these antigens have fuher 3 loci: DR, DQ, and DP. Class II MHC is identified by B cells and CD4+ cells.( T helper cells). ReReference:arsh mohan textbook pathology, 7th edition, pg no:49 <\p>