alexa Up-regulation of NK cytotoxic activity via IL-15 induction by different viruses: a comparative study.


Immunome Research

Author(s): Fawaz LM, SharifAskari E, Menezes J, Fawaz LM, SharifAskari E, Menezes J

Abstract Share this page

Abstract IL-15 is a recently identified cytokine that belongs to the four alpha-helix bundle cytokine family and possesses biological activities similar to those of IL-2. Its ability to induce effectors of NK activity suggests its involvement in innate immunity. In this study, we analyzed the effect of different viruses (HSV, EBV, respiratory syncitial virus, vesicular stomatitis virus, influenza virus, reovirus, and Sendai virus) on the up-regulation of NK activity in vitro. Exposure of human PBMC to the these viruses resulted in an immediate up-regulation of NK activity of PBMC via IL-15 induction; this effect was abrogated in the presence of mAbs to IL-15. Results of experiments conducted in parallel using mAbs to IL-15, as well as to other cytokines (IL-2, IL-12, IFN-gamma, and TNF-alpha), clearly indicated that IL-15 was specifically responsible for the observed effect. Furthermore, supernatants of virus-infected PBMC cultures significantly enhanced NK activity of uninfected PBMC in vitro. An increase of IL-15 protein levels 20 h postinfection was also confirmed in a bioassay using the IL-2-dependent cell line CTLL. Kinetic analysis of IL-15 mRNA expression using a semiquantitative RT-PCR revealed that the level of IL-15 messages peaked at different time points (up to 12 h) postinfection, depending on the nature of the virus. Taken together, these results suggest that the IL-15 response of the host to viral infection and the subsequent NK cell activation represent an important effector mechanism of the innate immune surveillance of the host against viral infections.
This article was published in J Immunol and referenced in Immunome Research

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version