2082
We have developed a three-layer Percoll density gradient that allows separation of the different granules and vesicles from human neutrophils ; in particular, it allows separation of specific and gelatinase granules .
 ( cell type: human neutrophils, 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:
 ( cell type: human neutrophils, None) 