9281
Furthermore , synergistic activation of ERK2 occurred in the absence of changes in intracellular Ca2 + , and was not blocked by inhibition of protein kinase C activity and represents a separate pathway by which CD19 regulates B cell function .
 ERK2, protein kinase C, CD19
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 ERK2, protein kinase C, CD19