Ultrastructural insights into the replication cycle of salmon pancreas disease virus (SPDV) using salmon cardiac primary cultures (SCPCs)

Abstract

The genus Alphavirus (Togaviridae) encompasses a diverse group of viruses infecting a wide range of invertebrate and vertebrate hosts worldwide (Coffey et al., 2016). Alphaviruses are predominantly arboviruses, with mosquito species being the most common invertebrate host along with ticks, biting fly and lice (Forrester et al., 2012;Powers et al., 2001). The wide range of vertebrate hosts include humans and non-human primates, equids, pigs, rodents, birds, reptiles, amphibians and fish. The majority of alphavirus species are therefore capable of replicating both in insect and in vertebrate cell lines (Strauss & Strauss, 1994). Several members of the genus are responsible for

Perspective Chapter: In Vitro Contracting Cardiomyogenic Models from Whole Fish Embryos and Larvae – Method, Properties, and Applications

“…Analysis of SCCs, larval heart, and adult fish heart suggested that the embryonic progenitors of heart tissue are able to differentiate in vitro in fully developed adult-like cardiomyocytes while the heart from larval stage revealed immature and unorganized sarcomere structures within the cells, so that heart cells of larvae are not fully differentiated. These kinds of observations were verified by electron microscopic analysis for SCCs generated from salmonids [29,32]. Additional confirmation of the theory was performed with zebrafish Tg (cmlc2:eGFP) larvae whose fluorescence indicates the expression of eGFP attached to cmcl2 in the heart [34].…”

“…Researchers have highlighted significant differences between murine and human cardiac electrophysiology, while noting the remarkable similarity between fish and human cardiac electrophysiology in terms of action potential properties and thus ion channels [24,25]. Compared to the human models, 3D spontaneously beating cardiomyogenic cultures from fishes are not dependent on clinical samples, and several experimental analyses confirmed the presence of fully developed cardiomyocytes organized in adult tissue phenotype and owning many biological characteristics in common with human cardiomyocytes [27][28][29][30][31][32][33][34]. The establishment of in vitro model systems with fish cells is therefore important not only for basic research in fish biology and virology but also for research in human medicine and pharmacology.…”

“…At this point, it is significant to use larvae that are at least at eye point stage and still within the yolk sac phase so that they are not actively feeding. Larvae of several salmonid species like rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta), maraena whitefish (Coregonus maraena), Atlantic salmon (Salmo salar), but also zebrafish (Danio rerio) or sturgeon species like Acipenser oxyrinchus were used to produce these cardiomyogenic in vitro systems [27][28][29][30][31][32][33][34].…”

“…The cell anatomy of SCC, which includes various cell types of the heart, has been extensively characterized using advanced imaging techniques such as confocal microscopy and electron microscopy, providing detailed information about the ultrastructure and spatial organization of cells [27][28][29][30][31][32][33][34].…”

“…Perspective Chapter: In Vitro Contracting Cardiomyogenic Models from Whole Fish Embryos… DOI: http://dx.doi.org/10.5772/intechopen.113858 and/or ventricular tissue of adult animals of the same species [31]. Studies on SCCs generated from larvae of zebrafish, rainbow trout, and Atlantic salmon have demonstrated important aspects of cell morphology within SCCs [27][28][29][30][31][32][33][34]. In fact, it has been shown that in vitro heart aggregates exhibit a syncytium-like structure with a high number of mitochondria, cell contact, and myofilaments, reflecting their contractile capacity, active metabolism, and long-term stability [27][28][29][30][31][32][33][34].…”