20984
Type II collagen , IGF - 1 , and MMP - 13 mRNA abundance and protein expression levels were determined by real - time polymerase chain reaction ( real - time PCR ) and western blot , respectively .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None