1853
By contrast, the MAP kinases ERK1 and ERK2 were fully activated by TPA or TCR stimulation and were not affected by Ca2+ , CD28, or CsA .
 ERK1, ERK2, MAP kinases, TCR
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:
 ERK1, ERK2, MAP kinases, TCR