Comparative production of IL-1 beta and IL-1 alpha by LPS-stimulated human monocytes: ELISAs measurement revisited.
There has always been an apparent discrepancy between the levels of IL-1 alpha and IL-1 beta mRNA and that of their corresponding proteins. Indeed, LPS-stimulated human monocytes produce about 10 times more IL-1 beta mRNA and IL-1 alpha mRNA, while the ratio of the corresponding proteins is the opposite, a difference that has been attributed to less efficient translation of IL-1 beta mRNA. Using a home-made ELISA that recognizes the 31-kDa precursor of IL-1 beta (proIL-1 beta), we found that LPS-stimulated human monocytes produced at least 20 times more IL-1 beta than IL-1 alpha, a ratio in accordance with the corresponding mRNA levels. This difference with previous reports is due to the fact that commercial ELISAs recognize, little if at all, proIL-1 beta. Furthermore, we found that cell lysis with CHAPS released significantly more IL-1 beta than did classical freeze-thawing.
Bailly
S
S
INSERM U294, Faculty X. Bichat, Paris, France.
Fay
M
M
Ferrua
B
B
Gougerot-Pocidalo
M A
MA
D000328:Adult; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D007375:Interleukin-1 / Q000032:analysis / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D046911:Macromolecular Substances; D009000:Monocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D011933:Reagent Kits, Diagnostic; D011994:Recombinant Proteins / Q000032:analysis
D007375:Interleukin-1; D008070:Lipopolysaccharides; D046911:Macromolecular Substances; D012333:RNA, Messenger; D011933:Reagent Kits, Diagnostic; D011994:Recombinant Proteins