Synthetic antimicrobial Nkl and Dic peptides are immunomodulatory but only Dic peptide can be therapeutic against nodavirus infection.

Aquaculture is a prosperous economic sector threatened by viral infections. Among the viruses threatening fish culture, Betanodavirus (NNV) is extremely important in the Mediterranean Sea affecting to highly traded species as European sea bass. In this context, application of antimicrobial peptides (AMPs) has arisen as a potential biotechnological tool. The aim of this work was to evaluate the therapeutic application of two European sea bass-derived AMPs, NK-lysin (Nkl) and dicentracin (Dic), against NNV infections. Synthetic Dic peptide was able to significantly reduce NNV-induced mortalities while Nkl failed to do so. Although neither Dic nor Nkl peptides were able to alter the transcriptional levels of NNV and the number of infected cells, Nkl seemed to increase the viral load per cell. Interestingly, both Nkl and Dic peptides showed immunomodulatory roles. For instance, our data revealed an interplay among different AMPs, at both gene and protein levels. Otherwise, Nkl and Dic peptides provoked an anti-inflammatory balance upon NNV infection, as well as the recruitment of macrophages and B cells to the target site of the infection, the brain. In conclusion, Dic can be proposed as a therapeutic candidate to combat NNV.

Fish HERC7: Phylogeny, Characterization, and Potential Implications for Antiviral Immunity in European Sea Bass.

E3 ubiquitin ligases, key components of the ubiquitin proteasome system, orchestrate protein degradation through ubiquitylation and profoundly impact cellular biology. Small HERC E3 ligases (HERC3-6) have diverse functions in mammals, including roles in spermatogenesis, protein degradation, and immunity. Until now, only mammals' HERC3, HERC5, and HERC6 are known to participate in immune responses, with major involvement in the antiviral response. Interestingly, an exclusive HERC7 has been characterized in fish showing great molecular conservation and antiviral roles. Thus, this study identifies and characterizes the herc7 gene in the European sea bass teleost. The European sea bass herc7 gene and the putative protein show good conservation of the promoter binding sites for interferons and the RCC1 and HECT domains characteristic of HERC proteins, respectively. The phylogenetic analysis shows a unique cluster with the fish-exclusive HERC7 orthologues. During ontogeny, the herc7 gene is expressed from 3 days post-fertilization onwards, being constitutively and widely distributed in adult tissues. In vitro, stimulated leucocytes up-regulate the herc7 gene in response to mitogens and viruses, pointing to a role in the immune response. Furthermore, sea bass herc7 expression is related to the interferon response intensity and viral load in different tissues upon in vivo infection with red-grouper betanodavirus (RGNNV), suggesting the potential involvement of fish HERC7 in ISGylation-based antiviral activity, similarly to mammalian HERC5. This study broadens the understanding of small HERC proteins in fish species and highlights HERC7 as a potential contributor to the immune response in European sea bass, with implications for antiviral defense mechanisms. Future research is needed to unravel the precise actions and functions of HERC7 in teleost fish immunity, providing insights into direct antiviral activity and viral evasion.

The susceptibility of shi drum juveniles to betanodavirus increases with rearing densities in a process mediated by neuroactive ligand-receptor interaction.

Nervous necrosis virus (NNV) is one of the greatest threats to Mediterranean aquaculture, infecting more than 170 fish species and causing mortalities up to 100% in larvae and juveniles of susceptible species. Intensive aquaculture implies stressed conditions that affect the welfare of fish and their ability to fight against infections. In fact, a higher susceptibility to NNV has been related to poor welfare conditions. In order to analyze the physiological link between stressed conditions and increased susceptibility to NNV, as well as its possible role in the pathogenesis of this disease, we reared shi drum (Umbrina cirrosa) juveniles (30.7 ± 3.10 g body weight), which are expected to be asymptomatic upon NNV infection, at three stocking densities (2, 15, and 30 kg/m3) for 27 days and subsequently challenged them with NNV. We firstly characterized the stressed conditions of the specimens before and after infection and recorded the mortalities, demonstrating that stressed specimens reared at 30 kg/m3 suffered mortalities. However, the viral loads in different tissues were similar in all experimental groups, allowing horizontal and vertical transmission of the virus from asymptomatic specimens. All of these data suggest that shi drum tolerates wide ranges of culture densities, although high densities might be a setback for controlling NNV outbreaks in this species. In an attempt to understand the molecular pathways orchestrating this susceptibility change in stressed conditions, we performed a transcriptomic analysis of four tissues under mock- and NNV-infected conditions. In addition to the modification of the exceptive pathways such as cell adhesion, leukocyte migration, cytokine interaction, cell proliferation and survival, and autophagy, we also observed a heavy alteration of the neuroactive ligand-receptor pathway in three of the four tissues analyzed. Our data also point to some of the receptors of this pathway as potential candidates for future pharmacological treatment to avoid the exacerbated immune response that could trigger fish mortalities upon NNV infection.

Synthetic Antimicrobial Peptides Fail to Induce Leucocyte Innate Immune Functions but Elicit Opposing Transcriptomic Profiles in European Sea Bass and Gilthead Seabream.

Antimicrobial peptides (AMPs) are promising molecules in diverse fields, including aquaculture. AMPs possess lytic effects on a wide range of pathogens, resulting in a potential replacement for traditional antimicrobials in aquaculture. In addition, they also have modulatory effects on host immune responses. Thus, the objective of this work was to evaluate the immunomodulatory capability of three known synthetic AMPs derived from European sea bass, NK-lysin (Nkl), hepcidin (Hamp), and dicentracin (Dic), in head-kidney cell suspensions from European sea bass and gilthead seabream. The tested peptides were neither cytotoxic for European sea bass nor gilthead seabream cells and failed to modulate the respiratory burst and phagocytosis activities. However, they modified the pattern of transcription of immune-related genes differently in both species. Peptides were able to promote the expression of marker genes for anti-inflammatory (il10), antiviral (mx, irf3), cell-mediated cytotoxicity (nccrp1, gzmb), and antibody responses (ighm) in European sea bass, with the Nkl peptide being the most effective. Contrary to this, the effects of those peptides on gilthead seabream mainly resulted in the suppression of immune responses. To conclude, European sea bass-derived peptides can be postulated as potential tools for immunostimulation in European sea bass fish farms, but more efforts are required for their universal use in other species.

Long-term complications according to silicone oil type. A single center cohort study.

PURPOSE: To study the incidence of macular edema (ME), ocular hypertension (OHT), emulsification and migration to the anterior chamber (AC) of silicone oil (SO) in patients after complex retina surgery, stratified by SO type. METHODS: Retrospective, cohort study. Patients who underwent retina surgery with SO injection and extraction in our center were included. We compared the complication rates of ME, OHT, emulsification and migration to the AS according to SO type (1300cSt, 5700cSt and heavy SO). Data on age, sex, emulsification time, duration of the tamponade, previous retina surgeries and diagnosis were also gathered and included in a multivariate analysis. RESULTS: We included 163 patients (mean age of 64.8 years; mean duration of the tamponade: 11 months). Rates of emulsification, ME, OHT and SO migration to the AC were similar in all groups (p = 0.998, 0.668, 0.915 and 0.360). ME was the most frequent complication (33.3-47.8%), which resolved after SO extraction in 77.6% of cases. The majority of cases with OHT persisted (61.7%). Emulsification was related to younger age (OR 0.94) and longer duration of the tamponade (OR 1.04). The odds of SO migration to the AC increased with emulsification (OR 2.78), recurrent retinal detachment (OR 0.99) and aphakia (OR 4.05). CONCLUSIONS: We propose SO extraction as the preferred treatment for ME during SO tamponade. SO extraction should be performed sooner in younger patients to avoid emulsification. In selected patients, we suggest a longer duration of the tamponade up to 11 months with a reasonable safety profile, regardless of the SO type.

Regulation and distribution of European sea bass perforins point to their role in the adaptive cytotoxic response against NNV.

Cell-mediated cytotoxicity is a complex immune mechanism that involves the release of several killing molecules, being perforin (PRF) one of the most important effector players. Perforin is synthesized by T lymphocytes and natural killer cells in mammals and responsible for the formation of pores on the target cell membrane during the killing process. Although perforin has been extensively studied in higher vertebrates, this knowledge is very limited in fish. Therefore, in this study we have identified four prf genes in European sea bass (Dicentrarchus labrax) and evaluated their mRNA levels. All sea bass prf genes showed the typical and conserved domains of its human orthologue and were closely clustered by the phylogenetic analysis. In addition, all genes showed constitutive and ubiquitous tissular expression, being prf1.9 gene the most highly expressed in immune tissues. Subsequently, in vitro stimulation of head-kidney (HK) cells with phytohemagglutinin, a T-cell activator, showed an increase of all prf gene levels, except for prf1.3 gene. European sea bass HK cells increased the transcription of prf1.2 and prf1.9 during the innate cell-mediated cytotoxic activity against xenogeneic target cells. In addition, sea bass infected with nodavirus (NNV) showed a similar expression pattern of all prf in HK and brain at 15 days post-infection, except for prf1.3 gene and in the gonad. Finally, the use of a polyclonal antibody against PRF1.9 showed an increase of positive cells in HK, brain and gonad from NNV-infected fish. Taken together, the data seem to indicate that all prf genes, except prf1.3, appear to be involved in the European sea bass immunity, and probably in the cell-mediated cytotoxic response, with PRF1.9 playing the most important role against nodavirus. The involvement of the PRFs and the CMC activity in the vertical transmission success of the virus is also discussed.

Cytotoxic activity and gene expression during in vitro adaptive cell-mediated cytotoxicity of head-kidney cells from betanodavirus-infected European sea bass.

Cell-mediated cytotoxicity (CMC) is essential in eradicating virus-infected cells, involving CD8+ T lymphocytes (CTLs) and natural killer (NK) cells, through the activation of different pathways. This immune response is well-studied in mammals but scarcely in teleost fish. Our aim was to investigate the adaptive CMC using head-kidney (HK) cells from European sea bass infected at different times with nodavirus (NNV), as effector cells, and the European sea bass brain cell line (DLB-1) infected with different NNV genotypes, as target cells. Results showed low and unaltered innate cytotoxic activity through the infection time. However, adaptive CMC against RGNNV and SJNNV/RGNNV-infected target cells increased from 7 to 30 days post-infection, peaking at 15 days, demonstrating the specificity of the cytotoxic activity and suggesting the involvement of CTLs. At transcriptomic level, we observed up-regulation of genes related to T cell activation, perforin/granzyme and Fas/FasL effector pathways as well as apoptotic cell death. Further studies are necessary to understand the adaptive role of European sea bass CTLs in the elimination of NNV-infected cells.

Interactive effects of palladium (Pd) and microplastics (MPs) on metal bioaccumulation and biological responses in the Mediterranean mussel, Mytilus galloprovincialis.

This study investigates the potential of MPs as carriers of pollutants as they can strengthen bioaccumulation of toxic metals on marine organisms. For the first time, the interaction of the metal palladium (Pd) with the widespread MPs, both with increasing concentrations in water environments from anthropogenic sources, was tested. Mytilus galloprovincialis, an important seafood product, was exposed to Pd (24 h) in two ways: water-dissolved and MPs-adsorbed, with depuration followed for 144 h. Quantification of Pd in tissues shown an accumulation 2-3 times higher (59 % of initial Pd) for mussels exposed to MPs-adsorbed Pd and higher in digestive gland than when exposed to water-dissolved Pd (25 %; higher in gills). Additionally, it was demonstrated that Pd induced oxidative stress and altered the feeding behavior of mussels. Therefore, this work support MPs as being vectors of metals (i.e. Pd) to enhance their bioaccumulation on marine organisms which highlights ecological risk of these emerging pollutants.

Updating Our Knowledge on Fish Immunology.

Fish is the first group of vertebrates to appear during animal evolution [...].

Medición de resultados en reimplantes en el Hospital Universitario Central de Asturias (España): estudio retrospectivo / Measurement of replantation outcomes at Central University Hospital of Asturias (Spain): a retrospective study

Introducción y objetivo: Los reimplantes, salvo excepciones, son mejor solución para las amputaciones que la revisión del muñón, especialmente en miembro superior. En un contexto de optimización de resultados, es esencial la autoevaluación. Por ello, el objetivo del presente estudio es recoger los resultados funcionales (incluyendo variables objetivas y subjetivas) de los reimplantes realizados en nuestro Servicio de Cirugía Plástica del Hospital Universitario Central de Asturias (España) en la última década. Material y método: Evaluamos los resultados de los reimplantes realizados en nuestro servicio desde 2010 usando una sistemática similar a la empleada para una serie de casos analizada entre 2000 y 2009. Así, presentamos los resultados funcionales objetivos en rango articular, fuerza de prensión y discriminación sensitiva usando la Tabla de Mayo Modificada para amputaciones distales a muñeca y los Criterios de Chen para las proximales. Evaluamos los resultados subjetivos con el Cuestionario de Russell. Resultados: Desde enero de 2010 se realizaron 37 intentos de reimplante de miembro superior, 6 de ellos en 2021 (excluidos del análisis global). El 83.87% fueron distales a muñeca (la mayoría con afectación del 1er dedo) y el 48.39% accidentes laborales. La mayoría de las lesiones fueron por maquinaria cortante. La supervivencia global de los fragmentos reimplantados fue del 75%, con necrosis parciales y rigideces como principales complicaciones. El resultado medio fue aceptable, con algunos buenos resultados (la mayoría pulgares). Tuvimos 2 casos proximales con buenos resultados. La satisfacción de los pacientes fue mayor que en aquellos amputados. Todos menos 1 recomendarían el procedimiento. (AU)

Background and objective: Replantation rather than stump revision, is, with some exceptions, the best solution for amputations, specially in the upper limb. In order to optimize results, self-evaluation is essential. Therefore, the objective of the current study is to collect and analyze the functional outcomes (including objective and subjective variables) of replantation surgeries performed at our Department of Plastic Surgery at the University Central Hospital of Asturias (Spain) in the last decade. Methods: We evaluate the outcomes of replatations performed at our department from 2010, using a similar system of a previous case series from 2000 to 2009. Thus, objective functional outcomes include articular range of motion, prehension strength and sensitive discrimination regarding to Mayo Modified Table score for distal to wrist amputations and Chen Criteria for proximal ones. Subjective results were evaluated according to Russell Questionnaire. Results: From January 2010, 37 attempts of upper limb replantation were performed, 6 of them in 2021 (excluded from global analysis). 83.87% were distal to wrist (most of them affecting the thumb) and 48.39% work accidents. Most of the lesions were caused by cutting machinery. Global survival of the replanted fragments was 75%, with partial necrosis and stiffness as main complications. Mean result was acceptable, with some good results (most of them thumbs). We had 2 proximal cases with good results. Satisfaction among patients was bigger than in amputated ones. All of them but 1 would recommend the surgery. (AU)

Antimicrobial Peptides from Photosynthetic Marine Organisms with Potential Application in Aquaculture.

Aquaculture production is at a record level and is estimated to increase in the coming years. However, this production can be negatively affected by infectious diseases produced by viruses, bacteria, and parasites, causing fish mortality and economic losses. Antimicrobial peptides (AMPs) are small peptides that may be promising candidates to replace antibiotics because they are the first line of defense in animals against a wide variety of pathogens and have no negative effects; they also show additional activities such as antioxidant or immunoregulatory functions, which makes them powerful alternatives for use in aquaculture. Moreover, AMPs are highly available in natural sources and have already been used in the livestock farming and food industries. Photosynthetic marine organisms can survive under all kinds of environmental conditions and under extremely competitive environments thanks to their flexible metabolism. For this reason, these organisms represent a powerful source of bioactive molecules as nutraceuticals and pharmaceuticals, including AMPs. Therefore, in this study we reviewed the present knowledge about AMPs from photosynthetic marine organism sources and analyzed whether they could be suitable for use in aquaculture.

Priming European Sea Bass Female Broodstock Improves the Antimicrobial Immunity of Their Offspring.

Acquiring immunocompetence is essential in the development of fish embryos, as they are exposed to environmental pathogens even before they are fertilized. Despite the importance of the antimicrobial function as the first line of defense against foreign microorganisms, little knowledge is available about its role in larval development. In vertebrates, transgenerational immune priming influences the acquisition of immunocompetence of specimens, regulating the selective allocation of nongenetic resources to their progeny and modulating their development. In this work, we primed teleost European sea bass broodstock females with a viral protein expression vector in order to evaluate the innate immunity development of their offspring. Several antimicrobial functions, the pattern of expression of gene coding for different antimicrobial peptides (AMPs), and their protein levels, were evaluated in eggs and larvae during development. Our data determined the presence of antimicrobial proteins of maternal origin in eggs, and that female vaccination increases antimicrobial activities and the transcription and synthesis of AMPs during larval development.

Long-Term Effects of a Short Juvenile Feeding Period with Diets Enriched with the Microalgae Nannochloropsis gaditana on the Subsequent Body and Muscle Growth of Gilthead Seabream, Sparus aurata L.

Currently, microalgae are used in fish diets, but their long-term growth effect is unknown. In this experiment, juvenile seabream specimens were fed with microalgae-enriched diets for three months, and then transferred to a microalgae-free diet for 10 months to assess long-term effects up to commercial size (≈27 cm and ≈300 g). The juvenile diets contained Nannochloropsis gaditana at 2.5 or 5% inclusion levels, either raw (R2.5 and R5 groups) or cellulose-hydrolyzed (H2.5 and H5 groups). The body length and weight were measured in 75 fish group-1 at commercial stage. The size, number, and fibrillar density of white muscle fibers and the white muscle transverse area were measured in nine fish group-1 at commercial stage. The results showed the highest body weight in H5 at commercial stage. The white muscle transverse area and the white fibres hyperplasia and density also showed the highest values in H5, followed by H2.5. In contrast, the highest hypertrophy was observed in C and R2.5, being associated with the lowest muscle growth in both groups. These results showed a microalgae concentration-dependent effect in hydrolyzed diets as well as an advantageous effect of the hydrolyzed versus raw diets on the long-term growth of Sparus aurata.

ADVANTAGES OF OPTICAL COHERENCE TOMOGRAPHY AS A HIGH DYNAMIC RANGE IMAGING MODALITY IN SUBRETINAL HYPERREFLECTIVE MATERIAL.

PURPOSE: To describe the utility of high dynamic range optical coherence tomography imaging to study subretinal hyperreflective material (SHRM) in patients with age-related macular degeneration. METHODS: Clinical information including visual acuity and optical coherence tomography images (Heidelberg Engineering GmbH, Heidelberg, Germany) of patients undergoing antiangiogenic treatment for neovascular age-related macular degeneration and showing SHRM at baseline were retrospectively reviewed. Contrast between strong signal structures (high dynamic range image) reclassifying SHRM as hyperreflective (HyperR), isoreflective, and hyporeflective was increased. The patients at baseline, 3, 6, and 12-months follow-up were evaluated. RESULTS: Forty-four eyes were classified as 15 HyperR (34.1%), 21 as isoreflective (47.7%), and eight as hyporeflective (18.2%). During follow-up, hyporeflective SHRM disappeared in all cases, isoreflective SHRM faded in 16 cases (76.2%); HyperR SHRM remained in all cases. Hyporreflective SHRM showed a greater visual acuity improvement than HyperR SHRM group ( P = 0.033). After 12-month follow-up, only the hyporeflective and isoreflective groups significantly reduced the presence of fluid in 37.5% ( P = 0.250) and 46.62% ( P = 0.006) of the patients, respectively; outer retinal layers were disrupted more frequently in the presence of HyperR SHRM (ellipsoid zone, P = 0.16; external limiting membrane, P = 0.007). CONCLUSION: Contrast-enhanced optical coherence tomography images enabled us to classify SHRM according to its reflectivity, showing groups with different disappearance rates, visual acuity improvement, and outer retinal layer disruption. This easy-to-access tool may be helpful as a prognostic factor in neovascular age-related macular degeneration cases.

Immunity elicited by AMP-encoding plasmids fails to increase the protection of European sea bass against nodavirus.

Antimicrobial peptides (AMPs) are a potent arm of the innate immune system that can directly kill pathogens and induce immunomodulation. In the marine aquaculture, European sea bass (Dicentrarchus labrax L.) is one of the most prosperous species but is highly susceptible to nodavirus (NNV), which produces high rates of mortality in larvae and juvenile stages. Thus, we aimed to evaluate whether AMPs exert immunomodulatory and/or NNV-preventive actions in sea bass. To do this, plasmids encoding the sea bass AMPs dicentracin (pDIC), beta-defensin (pDB1), hepcidin (pHAMP2) or NK-lysin (pNKL) were generated and intramuscularly injected into sea bass juveniles to evaluate their immunomodulatory and anti-NNV roles. Sea bass muscle transcribes the AMPs and produces an increase in their circulating levels, along with an increase of the antibacterial activity. Immune-related gene analysis revealed a great activation of the inflammatory response and the recruitment of neutrophilic granulocytes at the site of injection. However, AMP-encoding plasmids, namely pHAMP2, negatively affected to NNV disease by increasing fish mortality. In conclusion, plasmids encoding AMPs show immunostimulatory effects on European sea bass but do not improve the resistance to NNV.

Vulvar dermatoses: a cross-sectional 5-year study. Experience in a specialized vulvar unit

Abstract Background: Vulvar diseases are common in the general population and have a negative impact on the quality of life. Objectives: To describe our experience as dermatologists in the management of vulvar dermatosis consultations. Methods: A retrospective observational study was conducted with patients who attended monographic vulvar consultations over a 5-year period. Clinical information was obtained from the patient's charts. Results: 148 women were studied. Their mean age was 43.24 years (standard deviation: 15.15 years), with ages ranging from 4 months to 80 years. 53.4% of patients took between 2 and 5 years to seek medical attention for the first time. The most frequent diagnosis was lichen sclerosus (41.9%), irritative eczema of the vulva (14.9%), and lichen simplex chronicus (10.1%). 83.8% reported anogenital itching, 66.2% pain, and 45.9% dyspareunia. The most frequently prescribed treatment was ultra-potent topical corticosteroids (clobetasol propionate; 41.2%). Patients with lichen sclerosus were significantly older than those who presented with any of the other diseases. No differences were found in terms of either the time of disease evolution or in symptom presentation. Study limitations: Retrospective study. Vulvar diseases with an infectious cause are usually managed in primary care, therefore, were not included. All patients were recruited from a single private hospital which limits the comparisons with the public health system. Conclusions: Vulvar diseases frequently occur and are associated with high morbidity. It is essential to promote the development of specific vulvar consultations in hospitals. Specialties such as dermatology, gynecology, urology, or physiotherapy must be part of these units.

Vulvar dermatoses: a cross-sectional 5-year study. Experience in a specialized vulvar unit.

BACKGROUND: Vulvar diseases are common in the general population and have a negative impact on the quality of life. OBJECTIVES: To describe our experience as dermatologists in the management of vulvar dermatosis consultations. METHODS: A retrospective observational study was conducted with patients who attended monographic vulvar consultations over a 5-year period. Clinical information was obtained from the patient's charts. RESULTS: 148 women were studied. Their mean age was 43.24 years (standard deviation: 15.15 years), with ages ranging from 4 months to 80 years. 53.4% of patients took between 2 and 5 years to seek medical attention for the first time. The most frequent diagnosis was lichen sclerosus (41.9%), irritative eczema of the vulva (14.9%), and lichen simplex chronicus (10.1%). 83.8% reported anogenital itching, 66.2% pain, and 45.9% dyspareunia. The most frequently prescribed treatment was ultra-potent topical corticosteroids (clobetasol propionate; 41.2%). Patients with lichen sclerosus were significantly older than those who presented with any of the other diseases. No differences were found in terms of either the time of disease evolution or in symptom presentation. STUDY LIMITATIONS: Retrospective study. Vulvar diseases with an infectious cause are usually managed in primary care, therefore, were not included. All patients were recruited from a single private hospital which limits the comparisons with the public health system. CONCLUSIONS: Vulvar diseases frequently occur and are associated with high morbidity. It is essential to promote the development of specific vulvar consultations in hospitals. Specialties such as dermatology, gynecology, urology, or physiotherapy must be part of these units.

Antigen Presentation and Autophagy in Teleost Adaptive Immunity.

Infectious diseases are a burden for aquaculture. Antigen processing and presentation (APP) to the immune effector cells that fight pathogens is key in the adaptive immune response. At the core of the adaptive immunity that appeared in lower vertebrates during evolution are the variable genes encoding the major histocompatibility complex (MHC). MHC class I molecules mainly present peptides processed in the cytosol by the proteasome and transported to the cell surface of all cells through secretory compartments. Professional antigen-presenting cells (pAPC) also express MHC class II molecules, which normally present peptides processed from exogenous antigens through lysosomal pathways. Autophagy is an intracellular self-degradation process that is conserved in all eukaryotes and is induced by starvation to contribute to cellular homeostasis. Self-digestion during autophagy mainly occurs by the fusion of autophagosomes, which engulf portions of cytosol and fuse with lysosomes (macroautophagy) or assisted by chaperones (chaperone-mediated autophagy, CMA) that deliver proteins to lysosomes. Thus, during self-degradation, antigens can be processed to be presented by the MHC to immune effector cells, thus, linking autophagy to APP. This review is focused on the essential components of the APP that are conserved in teleost fish and the increasing evidence related to the modulation of APP and autophagy during pathogen infection.

Profile of Innate Immunity in Gilthead Seabream Larvae Reflects Mortality upon Betanodavirus Reassortant Infection and Replication.

Historically, gilthead seabream (Sparus aurata) has been considered a fish species resistant to nervous necrosis virus (NNV) disease. Nevertheless, mortality in seabream hatcheries, associated with typical clinical signs of the viral encephalopathy and retinopathy (VER) disease has been confirmed to be caused by RGNNV/SJNNV reassortants. Because of this, seabream larvae at 37 and 86 days post-hatching (dph) were infected by immersion with RGNNV/SJNNV and SJNNV/RGNNV reassortants under laboratory conditions, and mortality, viral replication and immunity were evaluated. Our results show that gilthead seabream larvae, mainly those at 37 dph, are susceptible to infection with both NNV reassortant genotypes, with the highest impact from the RGNNV/SJNNV reassortant. In addition, viral replication occurs at both ages (37 and 86 dph) but the recovery of infective particles was only confirmed in 37 dph larvae,; this value was also highest with the RGNNV/SJNNV reassortant. Larvae immunity, including the expression of antiviral, inflammatory and cell-mediated cytotoxicity genes, was affected by NNV infection. Levels of the natural killer lysin (Nkl) peptide were increased in SJNNV/RGNNV-infected larvae of 37 dph, though hepcidin was not. Our results demonstrate that the seabream larvae are susceptible to both NNV reassortants, though mainly to RGNNV/SJNNV, in an age-dependent manner.