Fibroblasts Express Immune Relevant Genes and Are Important Sentinel Cells during Tissue Damage in Rainbow Trout (Oncorhynchus mykiss) (original) (raw)

Collagen regulates the activation of professional phagocytes of the teleost fish gilthead seabream

Molecular Immunology, 2009

The innate immune system mediates the initial inflammatory response that follows infection or injury. Although the innate immune response of fish to infection has been relatively well characterized during recent years at both cellular and molecular levels, no studies have examined the role of extracellular matrix (ECM) in the regulation of innate immunity and inflammation. We report here that collagen and gelatin in vitro were able to prime the respiratory burst of phagocytes from the bony fish gilthead seabream. In addition, collagen and gelatin induced a specific set of immune-related and ECM remodelling enzymes that substantially differed from that induced by pathogen-associated molecular patterns. Notably, both collagen and gelatin induced the expression of interleukin-1 , chemokine (C-C motif) ligand 4 and matrix metalopeptidases (MMP) 9 and 13 in acidophilic granulocytes and macrophages but were unable to significantly increase the expression of other pro-inflammatory genes. Furthermore, it was found that the MMP2/MMP9 inhibitor V had a dose-dependent inhibitory effect on seabream phagocyte activation by either collagen or gelatin. In contrast, pre-treatment of collagen and gelatin by collagenase resulted in a higher stimulatory capacity compared to non-digested proteins.

Main Components of Fish Immunity: An Overview of the Fish Immune System

Fishes

Cellular immune responses consist of innate and adaptive cell-mediated immune mechanisms, where all leukocyte subpopulations are included. Among these are vital processes such as cell-mediated cytotoxicity and phagocytosis. The main cellular constituents of the fish immune system are macrophages, granulocytes, dendritic cells, NK cells, and cytotoxic T cells. This review provides the latest information on cellular defense mechanisms of fish and provides an overview of the function of the mucosal immune system in maintaining the general health of fish. Here, we discuss the fundamental ideas that underpin mucosal immune responses in teleosts, as well as the innate and adaptive immune cells and the molecules that play a role in these immune responses. Moreover, cytokine molecules and pathways in teleosts have been reported to focus on several kinds of associated immunity. Importantly, we also review antigen processing and presentation. The knowledge reported here will enable better und...

Chronic inflammatory cells with epithelial cell characteristics in teleost fishes

Veterinary pathology, 1989

Certain cells that participate in the chronic inflammatory response of teleost fishes have many features typical of epithelioid cells of mammals. Such features include high metabolic activity, frequent phagolysosomes, and cytoplasmic interdigitations between adjacent cells; however, the epithelioid granulomas formed in response to certain diseases in teleost fishes also have several features associated with epithelial cells. Cases of ulcerative mycosis or acid-fast bacterial infection in Atlantic menhaden (Brevoortia tyrannus), fungal infection in silver perch (Bairdiella chrysoura), and mycobacteriosis in Mozambique tilapia (Oreochromis mossambicus) had epithelioid cells that were joined together by well-formed desmosomes with tonofilaments. "Mature granulomas" of the ulcerative mycosis-infected menhaden stained positively for cytokeratin, a cytoskeletal protein that is considered to be highly specific for epithelial cells. The consistent presence of these heretofore unre...

Fish skeletal muscle tissue is an important focus of immune reactions during pathogen infection

Developmental & Comparative Immunology, 2017

Skeletal muscle in mammals can express and secrete immune-related molecules during pathogen infection. Despite in fish is known that classical immune tissues participate in innate immunity, the role of skeletal muscle in this function is poorly understood. To determine the immunocompetence of fish skeletal muscle, juvenile fine flounder (Paralichthys adpersus) were challenged with Vibrio ordalii. Different Toll-like receptors, pro-inflammatory cytokines (TNFa, Il-1b, and IL-8), and immune-effector molecules (NKEF and the antimicrobial peptides hepcidin and LEAP-2) were analyzed. Infection initially triggered IL-1b upregulation and P38-MAPK/AP-1 pathway activation. Next, the NFkB pathway was activated, together with an upregulation of intracellular Toll-like receptor expressions (tlr3, tlr8a tlr9, and tlr21), TNFa production, and leap-2 expression. Finally, transcriptions of il-1b, il-8, tnfa, nkef-a, and hepcidin were also upregulated. These results suggest that fish skeletal muscle is an immunologically active organ that could play an important role against pathogens.

Fish cell cultures as in vitro models of pro-inflammatory responses elicited by immunostimulants

Fish & Shellfish Immunology, 2012

We have tested the elicitation of innate defence-related responses in two stromal cell lines derived from the spleen (trout splenic stroma, TSS) and the pronephros (trout pronephric stroma-2, TPS-2) of rainbow trout (Oncorhynchus mykiss) after they were exposed to different concentrations of lipopolysaccharide (LPS), levamisole, or polyinosinic polycytidylic acid (poly-I:C). For comparison, cultures of rainbow trout head kidney macrophages were also included in the study, and the effect of the immunostimulants on the phagocytic activity, the intracellular and extracellular reactive oxygen species and nitric oxide production were assayed. Although the responses varied depending upon the concentration of the immunostimulants and the particular cell line, our results demonstrate that those activities were enhanced in the TSS and TPS-2 cell lines after exposure to any of the immunostimulants. These results indicate that the stromal cells of the main lympho-haemopoietic organs of O. mykiss develop innate defence responses, which are enhanced by well-known immunostimulants. In addition, such enhancement of the defence responses in the TSS and TPS-2 cell lines could be also elicited when they were exposed to conditioned supernatants from levamisole-or poly I:C-stimulated HK macrophage cultures, thus demonstrating that the haemopoietic stromal cells respond to macrophage-derived factors. Moreover, we demonstrate that the stromal cell lines constitutively expressed the Toll-like receptors TLR3, TLR5 and TLR9 genes. The results are discussed considering the role of the lympho-haemopoietic stromal cells in the innate immune responses, and the possibility of using histiotypic cell cultures of nonleucocyte cells of the haemopoietic organs to develop in vitro methods to select new immunostimulant candidates for aquaculture.

Major components of fish immunity: a review

2016

Fish are fascinating creatures with a certain degree of immunity comparable to those of mammals. The fish's immune system consists of two major components, innate and adaptive immunities. Innate immunity is non-specific and acts as the primary line of protection against pathogen invasion while adaptive immunity is more specific to a certain pathogen/following adaptation. Innate immunity consists of the non-specific cellular and the non-specific humoral components. The non-specific cellular component consists of toll-like receptors (TLRs), macrophages, neutrophils, eosinophils and non-specific cytotoxic cell while the non-specific humoral component involves lysozyme, the complement, interferons, C-reactive proteins, transferrins and lectins. They work together at the initial stage to prevent pathogen invasion. On the other hand, the adaptive immune system consists of highly specilised systemic cells and processes that are separated into two main components: the humoral and cellul...

The innate and adaptive immune system of fish

Infectious Disease in Aquaculture, 2012

This chapter describes what is known about the main components and responses of the innate and adaptive immune system of fi sh. The chapter fi rst reviews the organs, cells and molecules of the immune system known in a few economically important or model fi sh species. Molecular evidence suggests a similar immune system exists throughout the jawed vertebrates yet marked differences are also apparent. The innate parameters are at the forefront of fi sh immune defence and are a crucial factor in disease resistance. The adaptive response of fi sh is commonly delayed but is essential for long lasting immunity and a key factor in successful vaccination.