4563
Human immunodeficiency virus type 1 Vpr is a virion - associated , regulatory protein that is required for efficient viral replication in monocytes / macrophages .
 Human immunodeficiency virus type 1 Vpr
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 Human immunodeficiency virus type 1 Vpr