517
Recently, the defective gene in group II type II MHC CID has been isolated and termed CIITA .
 MHC, defective gene, CIITA
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 MHC, defective gene, CIITA