Acute immune responses in zebrafish and evasive behavior of a parasite – who is winning?

Frontiers in Cellular and Infection Microbiology

Cellular and Infection Microbiology

Sebastian Kjeldgaard-Nintemann¹  Carlota Marola Fernandez Gonzalez²  Moonika Haahr Marana³  Heidi Mathiessen³  Cyril Henard³  Louise von Gersdorff Jørgensen³  Sara Vebæk Gelskov³  Julie Algreen Reimer³ 

[1] Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark;Department of Science and Environment, Roskilde University, Roskilde, Denmark;Experimental Fish Models (ExFiMo), Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark;

关键词: zebrafish;    innate immunity;    imaging;    inflammation;    neutrophils;    macrophages;    Ichthyophthirius multifiliis;   

DOI  :  10.3389/fcimb.2023.1190931

 received in 2023-03-21, accepted in 2023-05-26,  发布年份 2023

来源: Frontiers

【 摘 要 】

The protozoan parasite Ichthyophthirius multifiliis is an economically important parasite for the aquaculture- and ornamental fish industry. The parasite is abundant worldwide and infects the skin, gills and fins of freshwater fish species. For approximately the last fifty years the innate and protective immune mechanisms induced by I. multifiliis have been in focus in different fish hosts. By utilizing transgenic zebrafish, new tools to investigate this have emerged. The aim of this study was therefore to elucidate early immune responses in zebrafish larvae by using gene expression and in vivo imaging of neutrophil and macrophage behavior during infection. For the first time, zebrafish larvae were infected with the parasite and infection dynamics, parasite size and host-parasite interactions were investigated. Results showed that the larvae responded with mild inflammation and that the 12 compared to 5 days post fertilization larvae were significantly less susceptible. It was furthermore observed that neutrophils and macrophages were attracted to the parasites and that neutrophils reacted with neutrophil extracellular traps (NETs) when fighting the parasite. The parasite was rotating vigorously, presumably to impede the neutrophils and macrophages from attaching to it but on rare occasions, neutrophils and macrophages were able to kill the parasite. Based on these observations, we concluded that the parasite uses the rotation as an immune evasive strategy and that the zebrafish larvae respond with high activity from neutrophils and macrophages locally but systemically only with mild inflammation.

【 授权许可】

Unknown   
Copyright © 2023 Mathiessen, Kjeldgaard-Nintemann, Gonzalez, Henard, Reimer, Gelskov, Marana and Jørgensen