8652
Taken together, substitution of Arg551 does not enhance the IL-4 signal for generation of germline epsilon transcript, whereas the substitution of Ile50 contributes to enhancement of IgE synthesis .
 IL-4, IgE
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:
 IL-4, IgE