5876
The B cell-associated surface molecule CD40 plays a key role in T cell-dependent B cell maturation , as individuals with defects in either CD40 or its ligand are impaired in immunoglobulin isotype class switching and germinal center formation .
 protein: CD40; protein: B cell-associated surface molecule; protein: CD40; protein: immunoglobulin
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
 Entities: CD40, B cell-associated surface molecule, CD40, immunoglobulin 
Answer:
 protein: CD40; protein: B cell-associated surface molecule; protein: CD40; protein: immunoglobulin