8223
Histological slides of one biopsy of each patient ( formalin - fixed and paraffin - embedded ) were stained with a Modified Giemsa ( MG ) , the Warthin - Starry ( WS ) , and an immunohistochemical method ( IMM ) using purified polyclonal H . pylori antiserum ( DAKO B471 ) .
 None
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 None