20148
To examine the interaction between macrophages and airway epithelial cells after exposure to crotonaldehyde , BEAS - 2B and A549 cells were treated with conditioned media from a human monocytic leukemia cell line ( THP - 1 ) cells stimulated with crotonaldehyde .
 Chemical: crotonaldehyde; Chemical: crotonaldehyde
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: crotonaldehyde; Chemical: crotonaldehyde