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 .
 human neutrophils
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:
 human neutrophils