11360
Although CD40 lacks intrinsic tyrosine kinase activity, its ligation induces protein tyrosine phosphorylation , which is necessary for several CD40 -mediated events .
 CD40, CD40
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:
 CD40, CD40