Inflammation in Fish As Seen from A Morphological Point of View with Special Reference to the Vascular Compartment

Abstract

Modern bony fishes or teleosts are increasingly being used as model organisms for human diseases. Ambitious mapping programmes have revealed parts of or entire genomes of several species. This information suggests that there are several similarities between the mammalian and teleost immune systems, but also important differences. These differences are especially evident in the anatomical and functional constructions. However, compared to mammals, morphological studies of the immune system and in particular the inflammatory responses in fish are scarce, much due to a general lack of good cell markers. This review seeks to give an overview of the current knowledge of the teleost immune system related to inflammation and morphological research. The emphasis is placed on coronary changes which may be observed in salmonids over the size of 10 cm. Here, the immunopathological picture has some resemblance to that observed in similar changes in humans.

In situ localisation of major histocompatibility complex class I and class II and CD8 positive cells in infectious salmon anaemia virus (ISAV)-infected Atlantic salmon

“…ISAV antigen was detected in cells adjacent to melanomacrophages but melanomacrophages did not show labelling for ISAV antigen at this early stage of infection. Melanomacrophages are a leucocyte subpopulation (reviewed by Koppang et al [34]) that contributes to the response of fish to foreign materials including infectious agents. Melanomacrophage accumulations are sites of long term antigen retention [35] and have been shown to be sites of lymphocyte recirculation [36].…”

Identification and characterization of a novel intraepithelial lymphoid tissue in the gills of Atlantic salmon

“…The germinal centres of the tonsils contain both B and T cells, but IgM + cells were not detected in the intraepithelial cell aggregations in this study. Morphological investigations of the teleost immune system are severely hampered by the lack of leukocyte cell markers (Koppang et al 2007). Currently, our laboratory is collaborating with others to establish useful salmonid T-cell markers.…”

Comparative cardiac pathological changes of Atlantic salmon (Salmo salar L.) affected with heart and skeletal muscle inflammation (HSMI), cardiomyopathy syndrome (CMS) and pancreas disease (PD)

“…Atlantic salmon as with other teleosts exhibits both innate and adaptive immune responses (Koppang et al, 2007;Nam et al, 2003;Liu et al, 2008;Moore et al, 2005). Initially, the innate immune system responds to pathogens include the actions of neutrophils, macrophages, mast cells, dendritic cells, and natural killer cells.…”