3816
Products of immune cells such as transfer factor and lymphokines form the third and possibly most important group of immune - stimulating agents .
 GENE: transfer factor
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
 Entities: transfer factor 
Answer:
 GENE: transfer factor