15466
The activation of the complement cascade , a cornerstone of the innate immune response , produces a number of small ( 74 - 77 amino acid ) fragments , originally termed anaphylatoxins , that are potent chemoattractants and secretagogues that act on a wide variety of cell types .
 amino acid
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 amino acid