13786
Consistent with the requirement for PC4 in the reconstituted system , OCA-B was found to interact directly with PC4 .
 PC4, PC4, OCA-B
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 PC4, PC4, OCA-B