https://openworks.mdanderson.org/sumexp22/1127/thumbnail.jp

Clowers, Michael J

Garcia, Samantha Rose

Lu, Emily

Moghaddam, Seyed Javad

Ramesh, Ashwin Kumar

Sharma, Atul

Sharma, Jyotika

English

OpenWorks @ MD Anderson

• Polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) are a subset of pathologically activated neutrophils with immunosuppressive activity.• The pro-tumorigenic activity of PMN-MDSCs may be enhanced by the formation of neutrophil extracellular traps (NETs) –weblike structures of DNA-histone complexes extruded by activated neutrophils.• NET formation, or NETosis, has also been implicated in the recruitment of cancer cells to the tumor microenvironment (TME) and in promoting tumor metastasis.• While stimulatory factors released from the TME – such as neutrophil chemoattractant complement C5a – have been characterized as major triggers of NETosis, little is known about the effect of TME-associated inflammation in NET formation.In this preliminary study, we predict that COPD-like inflammation promotes NETosis in the lung tissue via a C5a-dependent mechanism.012345NETosis (%)Figure 3. NTHi exposure upregulates transcription of C5a pathway receptors. Quantitative polymerase chain reaction (qPCR) of C5a markers; normalization gene in parentheses; dotted line indicates baseline expression (n=3-5).Figure 2. COPD-like inflammation induces NETosis. (A) BALF from wild type (left) and NTHi-exposed (right) mice were stained with Sytox Green Nucleic Acid Stain forNETs (Data were pooled from two experimental replicates). (B) Quantification of NETosis, calculated as a ratio of NETs to total neutrophils.Figure 1. COPD-like inflammation promotes immune cell invasion and neutrophilic influx. (A) Representative compiled photomicrographs of whole lung and zoomed insections stained with hematoxylin and eosin (H&E); scale bar is 100 µm. (B) Quantification of immune cells in bronchoalveolar lavage fluid (BALF) by Wright-Giemsastaining (n=3-5). Data represent mean ±SEM.Our next steps include:• Validating our qPCR results on the protein level• Expanding the number of treatment groups to examine NTHiexposure and NETosis inhibition with DNase in a lung cancermouse model (CC-LR).We hypothesize that NTHi exposure promotes NETosis, tumor cellinvasion, and metastases in lung cancer through the upregulation ofdownstream C5a signaling present on tumor-associated PMN-MDSCs, and that treatment with NETosis inhibitor DNase willsignificantly reduce these pro-tumorigenic effects.Confirmation of these results may reveal the potential of NETosisinhibition by DNase as a targeted therapy in the treatment of lungcancer.Title of the Poster Presentation Goes HereAuthors of the Poster Presentation Goes HereInstitutional and/or Graduate School of Biomedical Sciences Affiliation Goes Here To examine the effect of COPD-like inflammation on NETosis and myeloid cell infiltration in the lung environment.Mouse ModelC57BL/6 mice were treated once weekly with 2.5 mg/mL of aerosolized NontypeableHaemophilus influenzae (NTHi) lysate from 6-to-14 weeks of age to induce a COPD-like phenotype.MethodsFrozen tissue, bronchoalveolar lavage fluid (BALF), and whole lung samples were collected to quantify myeloid cell infiltration, NETosis, and other changes to the lung environment.NTHi exposure increased neutrophil invasion and NETosis in the airways while also upregulating the transcription of c5aR1, TLR4, and RAGE receptors.IntroductionAimsMethodologyConclusionsFuture DirectionsFundingCreated with BioRenderResultsNTHiControl NTHiControlA BA BEL was supported by the CPRIT training award.COPD-like Inflammation Induces Neutrophil Invasion and NETosis via the C5a Pathway1 – Department of Pulmonary Medicine, University of Texas MD Anderson Cancer Center (MDACC), Houston, TX. 2 – MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX. 3 – Department of Critical Care, MDACC. Emily Lu1, Michael J. Clowers1,2, Atul Sharma3, Ashwin K. Ramesh3, Samantha R. Garcia3, Jyotika Sharma3, Seyed Javad Moghaddam1,2ControlNTHiControlNTHiCreated with BioRender

COPD-like Inflammation Induces Neutrophil Invasion and NETosis via the C5a Pathway

https://openworks.mdanderson.org/cgi/viewcontent.cgi?article=1127&context=sumexp22

COPD-like Inflammation Induces Neutrophil Invasion and NETosis via the C5a Pathway

Abstract

Similar works

Full text

Available Versions

OpenWorks @ MD Anderson