4064
In situ hybridizations of adult murine tissues demonstrate Spi-B mRNA in the medulla of the thymus , the white pulp of the spleen , and the germinal centers of lymph nodes .
 RNA: Spi-B mRNA; protein: Spi-B
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: Spi-B mRNA, Spi-B 
Answer:
 RNA: Spi-B mRNA; protein: Spi-B