CCL19 variants mediate chemotactic response via CCR7 in grass carp Ctenopharyngodon idella

Dev Comp Immunol. 2021 Sep:122:104127. doi: 10.1016/j.dci.2021.104127. Epub 2021 May 7.

Abstract

CC chemokine ligand 19 (CCL19) plays a key role in the regulation of immune responses including homeostasis, inflammation, and immune tolerance. In this study, two variants of CCL19 homologues (CCL19a2 and CCL19b) and CCR7 were investigated in grass carp Ctenopharyngodon idella. The three genes were widely expressed in immune tissues and could be modulated by stimulation with LPS, PHA and poly(I:C), and infection with Flavobacterium columnare and grass carp reovirus. In an in vitro chemotaxis assay, the recombinant CCL19a2 and CCL19b were active to promote the migration of HEK293 T cells expressing CCR7 and leucocytes isolated from the gills, head kidney and spleen. Moreover, their chemotactive effects were validated in vivo. We found that the cells recruited by CCL19a2 and CCl19b are mainly monocytes/macrophages expressing high levels of IL-1β, IFN-γ, colony stimulating factor 1 receptor (CSF1R) and MHC II. Our work suggests that CCL19a2 and CCl19b are involved in recruitment of antigen presenting cells in fish.

Keywords: Bacterial and viral infection; Chemokine; Chemokine receptor; Chemotaxis; Gene expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigen Presentation / immunology*
  • Base Sequence
  • Carps / immunology*
  • Carps / microbiology
  • Cell Line
  • Cell Movement / immunology
  • Chemokine CCL19 / genetics
  • Chemokine CCL19 / immunology*
  • Fish Diseases / immunology*
  • Fish Diseases / microbiology
  • Flavobacterium / immunology
  • Gills / cytology
  • Gills / immunology
  • HEK293 Cells
  • Head Kidney / cytology
  • Head Kidney / immunology
  • Humans
  • Interferon-gamma / metabolism
  • Interleukin-1beta / metabolism
  • Leukocytes / immunology*
  • Lipopolysaccharides / pharmacology
  • Macrophages / immunology
  • Monocytes / immunology
  • Phytohemagglutinins / immunology
  • Poly I-C / immunology
  • Receptors, CCR7 / metabolism*
  • Receptors, Granulocyte-Macrophage Colony-Stimulating Factor / metabolism
  • Reoviridae / immunology
  • Sequence Analysis, DNA
  • Spleen / cytology
  • Spleen / immunology

Substances

  • Chemokine CCL19
  • Interleukin-1beta
  • Lipopolysaccharides
  • Phytohemagglutinins
  • Receptors, CCR7
  • Receptors, Granulocyte-Macrophage Colony-Stimulating Factor
  • Interferon-gamma
  • Poly I-C

Supplementary concepts

  • Flavobacterium columnare