2375
The presence of androgen receptors in peripheral mononuclear leukocytes provides for the first time the experimental basis for an hypothesis of direct, receptor-mediated effects of androgens on mature immunocompetent cells .
 ( cell type: peripheral mononuclear leukocytes, None) , ( cell type: mature immunocompetent cells, None) , ( protein: androgen receptors, 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: peripheral mononuclear leukocytes, None) , ( cell type: mature immunocompetent cells, None) , ( protein: androgen receptors, None) 