5973
Receptors for leukocyte chemoattractants , including chemokines , are traditionally considered to be responsible for the activation of special leukocyte functions such as chemotaxis , degranulation , and the release of superoxide anions .
 ( protein: leukocyte chemoattractants, None) , ( protein: chemokines, 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: leukocyte chemoattractants, None) , ( protein: chemokines, None) 