4433
Gel mobility shift and immunoprecipitation analyses revealed that in addition to activating STAT3 ( signal transducer and activator of transcription-3 ) and STAT5 , IL-2 induced tyrosine and serine phosphorylation of STAT1 alpha , which formed IFN-gamma-activated sequence-binding complexes by itself and with STAT3 .
 STAT3, IFN-gamma-activated sequence-binding complexes, signal transducer and activator of transcription-3, STAT1 alpha, STAT3, IL-2, STAT5
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:
 STAT3, IFN-gamma-activated sequence-binding complexes, signal transducer and activator of transcription-3, STAT1 alpha, STAT3, IL-2, STAT5