7499
However, p38 MAPK is activated strongly and synergistically by either CD3/CD28 coligation or PMA/Ca2+ ionophore stimulation , which mimics TCR - CD3/CD28 -mediated signaling .
 ( protein: CD3/CD28, None) , ( protein: TCR, None) , ( protein: p38 MAPK, None) , ( protein: CD3/CD28, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( protein: CD3/CD28, None) , ( protein: TCR, None) , ( protein: p38 MAPK, None) , ( protein: CD3/CD28, None) 