Characterization of the gilthead seabream (Sparus aurata L.) immune response under a natural lymphocystis disease virus outbreak

Abstract

Lymphocystis or lymphocystis disease virus (LCDV) is distributed worldwide and affects many fresh and marine water fish species. LCDV is commonly found in aquaria fish species but also in farmed fish species, among them the gilthead seabream (Sparus aurata L.). The immune status of gilthead seabream (S. aurata) specimens under a natural outbreak of LCDV was studied. The replication of the virus was demonstrated in infected fish, but not in control fish. The results showed decreased total serum IgM levels and increased innate cellular immune response (peroxidase and respiratory burst activities) of head kidney leucocytes in LCDV-infected fish, compared to the values obtained in uninfected specimens. In addition, transcription of antiviral genes (ifn and irf3) was down-regulated in the skin of LCDV-positive fish as well as genes involved in cellular immunity (csf1r, mhc2a, tcra and ighm) that were down-regulated in skin and head kidney of infected fish. By contrast, the transcription of nccrp1 was up-regulated in head kidney after LCDV infection. These present results show that head kidney leucocytes are activated to encounter the virus at the sites of replication.

Dorso-ventral skin characterization of the farmed fish gilthead seabream (Sparus aurata)

“…To the best of our knowledge, this is the first time that the cell cycle of skin cells has been compared between different corporal regions. However, widening the study to the cell cycle of skin cells opens up new possibilities for analysing cell regulation in common fish skin infections such as lymphocystis [23] or vibriosis [24], a field with potential applications in fish aquaculture. In this sense, the apoptosis of isolated salmon skin cells increased upon in vitro exposure to Vibrio anguillarum [18].…”

Hints on T cell responses in a fish-parasite model: Enteromyxum leei induces differential expression of T cell signature molecules depending on the organ and the infection status

“…In all vertebrates, CTLs and NK cells are known to express several receptors, transcription factors and effector molecules in common [ 63 ]. Nevertheless, our results show that the increased cd8 expression detected is not correlated with changes in expression of nccrp1 , a receptor needed for recognition of target cells expressed in natural cytotoxic cells (NCC), the teleost NK equivalents [ 64 ]. CTLs also express Tbet and IFNγ [ 13 ], thus the increased expression of these molecules can also be attributed to such cell population.…”

Genome Sequencing and Transcriptome Analysis Reveal Recent Species-Specific Gene Duplications in the Plastic Gilthead Sea Bream (Sparus aurata)

“…These eurythermal and euryhaline characteristics, in combination with a notable resilience to aquaculture stressors, make this species a rather unique fish with a high plasticity to farming and challenging environments. This adaptation to varying culture conditions has been assessed in a number of physiological studies with focus on nutrition (Benedito-Palos et al, 2016;Simó-Mirabet et al, 2018;Gil-Solsona et al, 2019), chronobiology (Mata-Sotres et al, 2015;Yúfera et al, 2017), feeding behavior (López-Olmeda et al, 2009;Sánchez et al, 2009), stress (Calduch-Giner et al, 2010;Castanheira et al, 2013;Pérez-Sánchez et al, 2013;Bermejo-Nogales et al, 2014;Magnoni et al, 2017;Martos-Sitcha et al, 2017, 2019, or disease resilience (Cordero et al, 2016;Estensoro et al, 2016;Piazzon et al, 2018;Simó-Mirabet et al, 2018). However, the underlying genetic bases of this adaptive plasticity remain unknown.…”