708
The response to antigen proceeds at the T helper cell level through two independent forms of cellular collaboration , contact and lymphokine .
 protein: lymphokine; cell type: T helper cell
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 protein: lymphokine; cell type: T helper cell