Author : Amber Leigh Ortiz
Publisher :
ISBN 13 : 9780355601480
Total Pages : 149 pages
Book Rating : 4.6/5 (14 download)
Book Synopsis Use of a Listeria Monocytogenes Protein to Stimulate Immune Responses and Anti-tumor Effects by : Amber Leigh Ortiz
Download or read book Use of a Listeria Monocytogenes Protein to Stimulate Immune Responses and Anti-tumor Effects written by Amber Leigh Ortiz and published by . This book was released on 2017 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: Natural killer (NK) cells are a type of innate immune cell that secrete IFN when activated. IFN has pro-inflammatory effects and can act on tumor cells to kill them or inhibit their proliferation. NK cells can also exert direct anti-tumor cytolytic activity. Previous work showed that the Listeria monocytogenes (Lm) p60 protein indirectly promotes activation of NK cells to mediate cytokine production. The p60 protein contains two divergent LysM domains and one SH3 domain. The LysM1 domain is responsible for the immune stimulatory activity of the p60 protein and is present with the SH3 domain in a fragment of p60 termed "L1S." Like p60, recombinant L1S binds dendritic cells (DC) to stimulate their secretion of cytokines such as interleukin-18 (IL-18) and license them to promote activation of NK cells. The studies in this thesis investigated the nature of immune cell activation by L1S in vitro and in vivo through direct lung instillation. I found that instillation with wildtype L1S induced recruitment of inflammatory neutrophils and promoted accumulation of activated, IFN-producing, NK cells with increased cytolytic activity. I further showed that instillation of tumor-bearing mice with wildtype L1S protein significantly reduced burdens of established tumors. IFN and NK cells were required for these therapeutic effects. Further studies utilized simulated structure analysis and site-directed mutagenesis to explore the effects of specific amino acids in the LysM1 domain on the function of recombinant L1S protein. Specific amino acids in the LysM1 region were identified as critical for eliciting NK cell activity. Thus, my studies have improved our understanding of L1S immunostimulatory function and demonstrated its potential in vivo use for stimulation of NK cell anti-tumor responses.