15366
To address this deficit , we examined the effects of Pb on MHC - II surface expression , secondary T - cell activation markers ( CD80 , CD86 , CD40 ) , cell viability , cellular metabolic activity , and beta - hexosaminidase activity in RAW 267 . 4 macrophage cell lines , with changes in cell ultrastructure evaluated by electron and confocal microscopy .
 Chemical: Pb
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: Pb