Effect of granulocyte/macrophage colony-stimulating factor on human monocytes infected with influenza a virus. Enhancement of virus replication, cytokine release, and cytotoxicity
Bender, A.; Amann, U.; Jäger, R.; Nain, M.; Gemsa, D.
Journal of Immunology 151(10): 5416-5424
1993
ISSN/ISBN: 0022-1767 PMID: 8228234 Document Number: 419781
The activating properties of granulocyte/macrophage (GM)-CSF were studied in vitro with human monocytes infected by influenza A virus. When monocytes were pretreated for 8 h with GM-CSF (100 U/ml) and then exposed to influenza A virus, de novo virus protein synthesis was enhanced, more virus particles were released, and cells were killed at a higher rate. In virus-infected monocytes, GM-CSF induced a more rapid IFN-alpha release and potentiated production of TNF-alpha, IL-1 beta, and IL-6. Although GM-CSF or influenza A virus were each capable of independently activating TNF-alpha, IL-1 beta, and IL-6 gene transcription, a combination of both induced a massive cytokine mRNA accumulation which was readily translated into bioactive protein. Thus, GM-CSF may display a Janus-like action by accelerating virus infection but also by priming monocytes for elevated cytokine production. Whether the facilitated influenza A virus replication caused by GM-CSF may be counterbalanced by an improved cytokine response remains to be studied under more complex in vivo conditions.