Neutrophils are a type of innate immune cell that play a critical role in the acute inflammatory response by recognizing, phagocytizing and killing pathogens. Although their presence during infection is immensely significant for pathogen clearance, current research suggests that an overly robust neutrophil response may be detrimental to the host. Expression levels of the zebrafish chemokines Cxcl8-l1 and Cxcl8-l2, which are responsible for inducing neutrophil migration to a site of infection, have been shown to increase under inflammatory conditions caused by various PAMPs and infectious stimuli. Cxcl8 expression levels under inflammatory conditions caused by human viral infections, such as Influenza A virus infection, have yet to be studied.
The aim of this study is to utilize the zebrafish as a model to characterize the neutrophil response to IAV infection. Using the MPX-mCherry transgenic zebrafish line (red fluorescence-tagged neutrophils) and IAV-GFP (green fluorescence-tagged Influenza A virus), we hope to quantify neutrophil migration to a localized IAV infection in the swimbladder. Localized infection with IAV-GFP resulted in increased numbers of neutrophils in the swimbladder region and surrounding tissues, suggesting that neutrophils do migrate to a localized IAV infection. Additionally, through the systemic infection of AB zebrafish embryos, we hope to investigate how levels of expression of neutrophil migratory genes: Cxcl8-l1 and Cxcl8-l2, may be altered upon IAV infection. Preliminary data have revealed that the Cxcl8 genes are up-regulated during IAV infection, particularly between 12 and 24 hpi.
Bowman, Alexis Rae, "Characterizing the Neutrophil Response to Influenza A Virus Infection in the Zebrafish Model" (2016). Honors College. 373.