transforming-growth-factor-beta and Fish-Diseases

Several studies have looked into the use of basil, Ocimum basilicum (L.) in aquaculture as a dietary additive; however, more research is needed to see the possibility of it's including in nanocarriers in aquafeeds. An experiment was undertaken to highlight the efficacy chitosan-Ocimum basilicum nanocomposite (COBN), for the first time, on Nile tilapia (Oreochromis niloticus) growth, stress and antioxidant status, immune-related parameters, and gene expression. For 60 days, fish (average weight: 23.55 ± 0.08 g) were fed diets provided with different concentrations of COBN (g/kg): 0 g [COBN0], 1 g [COBN1], 2 g [COBN2], and 3 g [COBN3], where COBN0 was kept as control diet. Following the trial, the fish were challenged with pathogenic bacteria (Aeromonas sobria) and yeast (Candida albicans) infection. In comparison to the control (COBN0), a notable increase in growth parameters (weight gain, feed intake, and specific growth rate) and intestinal morphometric indices (average intestinal goblet cells count, villous width, and length) in all COBN groups was observed, where COBN2 and COBN3 groups had the highest values. The COBN diets significantly (p < 0.05) declined levels of serum triglycerides, glucose, cholesterol, and hepatic malondialdehyde. Moreover, the higher levels of serum biochemical biomarkers (growth hormone, total protein, globulin, and albumin), immunological parameters (phagocytic activity%, nitric oxide, and lysozyme), and hepatic antioxidant parameters (superoxide dismutase, total antioxidant capacity, and glutathione peroxidase) were obvious in the COBN2 and COBN3 groups followed by COBN1. The immune-antioxidant genes (TNF-α, IL-10, IL-1β, TGF-β, GPx, and SOD) were found to be considerably up-regulated in all COBN groups (COBN2 and COBN3 followed by COBN1). Fifteen days post-challenge with A. sobria and C. albicans, the highest survival rate was recorded in the COBN2 group (83.33 and 91.67%) followed by the COBN3 group (75 and 83.33%), respectively. The findings showed that a dietary intervention with COBN can promote growth, intestinal architecture, immunity, and antioxidant markers as well as protect O. niloticus against A. sobria and C. albicans infection. As a result, the COBN at a dose of 2 g/kg could be used as a food additive for the sustainable aquaculture industry.

Topics: Albumins; Animal Feed; Animals; Antioxidants; Chitosan; Cichlids; Diet; Dietary Supplements; Fish Diseases; Food Additives; Gene Expression; Glucose; Glutathione Peroxidase; Gram-Negative Bacterial Infections; Growth Hormone; Head Kidney; Interleukin-10; Malondialdehyde; Muramidase; Nanocomposites; Nitric Oxide; Ocimum basilicum; Superoxide Dismutase; Transforming Growth Factor beta; Triglycerides; Tumor Necrosis Factor-alpha

Topics: Animal Feed; Animals; Anti-Bacterial Agents; Bacillus; Bacillus subtilis; Cichlids; Diet; Dietary Supplements; Disease Resistance; Fish Diseases; Interleukin-10; Intestines; Probiotics; Streptococcus iniae; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

To evaluate the effects of dietary short chain fatty acids (SCFAs) on the intestinal health and innate immunity in crucian carp, a six-week feeding trial was carried out with following treatments: basal diet (BD), basal diet supplementation with 1% sodium acetate (BDSA), basal diet supplementation with 1% sodium propionate (BDSP) and basal diet supplementation with 1% sodium butyrate (BDSB). The results showed dietary BDSA, BDSP and BDSB could protect the host against oxidative stress by improving the activity of certain antioxidative enzymes (T-SOD, GSH-Px and CAT). Additionally, dietary SCFAs could enhance mucosal and humoral immune responses by improving certain innate immune parameters in serum and skin mucus productions (IgM, ACH50 and T-SOD). Furthermore, dietary BDSA and BDSP could up-regulate the expression of immune related genes (TNF-α, TGF-β and IL-8) and tight junction protein genes (occludin and ZO-1). Dietary BDSB could also elevate the expression of IL-8, TGF-β, ZO-1 and Occludin in the midgut. Although dietary differences of SCFAs didn't alter the α-diversity of the intestinal flora, they altered the core microbiota. Finally, the challenge trial showed that dietary basal diet supplementation with SCFAs could protect zebrafish against Aeromonas hydrophila. These results suggest that dietary SCFAs could improve innate immunity, modulate gut microbiota and increase disease resistance in the host, which indicated the potential of SCFAs as immunostimulants in aquaculture.

Topics: Aeromonas hydrophila; Animal Feed; Animals; Antioxidants; Diet; Dietary Supplements; Disease Resistance; Fatty Acids, Volatile; Fish Diseases; Gastrointestinal Microbiome; Gram-Negative Bacterial Infections; Interleukin-8; Occludin; Superoxide Dismutase; Transforming Growth Factor beta; Zebrafish

This study aims to highlight the effects (8 weeks) of dietary antimicrobial peptides (AMPs, a compound of 6 kDa and 5 kDa from intestine) on intestinal morphological functions and health status in grass carp (Ctenopharyngodon idellus). Fish were supplemented with various gradient concentrations of AMPs, including M0 (0 mg/kg), M1 (100 mg/kg), M2 (200 mg/kg), M3 (400 mg/kg), M4 (800 mg/kg) and M5 (1600 mg/kg). Our results showed that amylase, lipase, chymotrypsin enzymatic levels, and total antioxidant capacity (T-AOC) were significantly increased (p < 0.05), while malondialdehyde (MDA) content was significantly decreased in the intestines of the AMP treated groups compared to the M0. Histological analysis revealed villus height and crypt depth of foregut and midgut in the M4 group were significantly different (p < 0.05) compared to the M0. In the M3 group, the gene expression levels of IL-1β were significantly up-regulated, while levels of IL10 and TGF-β were significantly down-regulated than other treated and control groups. The abundance of Firmicutes was significantly increased (p < 0.05), while the Planctomycetes abundance was decreased at phylum level in M1-M5 groups. Subsequent to the AMP treatment, fish were injected with Aeromonas. hydrophila to assess disease resistant potential. In A. hydrophila injected M3-group, the gene expressions of IL-1β, IL8, and TNF-α were significantly down-regulated while that of TGF-β was significantly up-regulated, and IL10 showed no significant difference compared to the control. Further, AMPs also increased the abundance of the Acidobacteria, Proteobacteria, and Patescibacteria, and decreased the abundance of the Fusobacteria and Firmicutes. Therefore, dietary AMPs (400-800 mg/kg) boosted intestinal health by promoting intestinal morphology, digestive and antioxidant capacities, immunity, and intestinal microbiota in C. idellus.

Topics: Aeromonas hydrophila; Animal Feed; Animals; Antimicrobial Peptides; Antioxidants; Carps; Diet; Disease Resistance; Fish Diseases; Fish Proteins; Gastrointestinal Microbiome; Gram-Negative Bacterial Infections; Interleukin-10; Intestines; Signal Transduction; Transforming Growth Factor beta

The disease caused by Micropterus salmoides rhabdovirus (MSRV) has brought substantial economic losses to the largemouth bass aquaculture industry in China. Vaccination was considered as a potential way to prevent and control this disease. As a kind of sustained and controlled release system, alginate and chitosan microspheres (SA-CS) are widely used in the development of oral vaccination for fish. Here, we prepared a king of alginate-chitosan composite microsphere to encapsulate the second segment of MSRV glycoprotein (G2 protein) and then evaluated the immune effect of the microsphere vaccine on largemouth bass. Largemouth bass were vaccinated via intragastric immunization by different treatments (PBS, SA-CS, G2 and SA-CS-G2). The results showed that a stronger immune response including serum antibody levels, immune-related physiological indexes (acid phosphatase, alkaline phosphatase, superoxide dismutase and total antioxidant capacity) and the expression of immune-related gene (IgM、IL-8、IL-1β、CD4、TGF-β、TNF-α) can be induced obviously with SA-CS-G2 groups compared with G2 groups when fish were vaccinated. Furthermore, fish were injected with a lethal dose of MSRV after immunization for 28 days, and the highest relative percentage survival (54.8%) was observed in SA-CS-G2 group (40 μg per fish), which is significantly higher than that of G2 group (25.8%). This study showed that alginate-chitosan microspheres as the vaccine carrier can effectively improve the immune effect of oral vaccination and induce better immune protection effect against MSRV infection.

Topics: Acid Phosphatase; Alginates; Alkaline Phosphatase; Animals; Antioxidants; Bass; Chitosan; Delayed-Action Preparations; Fish Diseases; Immunoglobulin M; Interleukin-8; Microspheres; Rhabdoviridae; Superoxide Dismutase; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha; Vaccines, Subunit; Vaccines, Synthetic

Disease problems will seriously restrict the sustainable development of aquaculture, and the environmental-friendly prevention strategies are urgently needed. Probiotics and quorum-quenching enzyme are innovative strategies to control bacterial diseases. Firstly, the bacteriostatic activity of Bacillus subtilis wt55 strain and quenching enzyme AiiO-AIO6 on the growth of Aeromonas veronii were tested in vitro, and the results showed wt55 inhibit the growth of A. veronii, but AiiO-AIO6 did not. Then, the synergistic effects of simple combination of B. subtilis wt55 and AiiO-AIO6 were evaluated next. The results showed this combination could improve the survival rate and significantly reduce the number of invasive A. veronii in gut after challenge compared to the other groups, corresponding to the lower intestinal alkaline phosphatase activity. One of its effect mechanisms is the combination could inhibit the growth of A. veronii in vitro; the other is direct immersion of germ-free zebrafish proved AiiO-AIO6 did not directly regulate the innate immune response of the host, but wt55 did it, and the simple combination group could significantly reduce the expression of nuclear factor kappa-B (NF-κB) and proinflammatory cytokine interleukin-1β (IL-1β), increase the expression of lysozyme gene; and the third is intestinal microbiota also plays a regulatory role: the gut microbiota from combination group could significantly inhibit the expression of IL-1β and NF-κB, and increased the expression of transforming growth factor-β (TGF-β) and lysozyme. Given the effectiveness of this simple combination, a B. subtilis quorum-quenching recombinant expression strain in which AiiO-AIO6 was surface displayed on the spores and secreted by vegetative cells was built. The results showed that the survival rate after challenge was lower than that of the group treated with AiiO-AIO6 or wt55 alone, and the expression of proinflammatory cytokine IL-1β and NF-κB were significantly higher. Our study demonstrated the effectiveness of B. subtilis and AiiO-AIO6 simple combination and established an efficient B. subtilis expression system.

Topics: Aeromonas veronii; Alkaline Phosphatase; Animals; Bacillus subtilis; Fish Diseases; Gram-Negative Bacterial Infections; Interleukin-1beta; Muramidase; NF-kappa B; Transforming Growth Factor beta; Transforming Growth Factors; Zebrafish

Trichodinids are peritrichous ciliated protozoa that affect both wild and cultured fishes. Several Trichodina species have low host specificity and are morphologically distinct, facilitating their identification based primarily on the presence of adhesive discs and the number of attached denticles. A trichodinid species named Trichodina compacta was first reported by Van As and Basson (1989) (Protozoa: Ciliophora: Peritrichia). However, in trichodinid infestations, morphological characteristics are insufficient for identifying the infesting species. Therefore, molecular and phylogenetic analyses are considered to be promising and useful tools for identifying the infesting species. This study aimed to achieve the molecular identification of a trichodinid infestation in Nile tilapia and to construct the phylogenetic relationships between the identified species and other peritrichous parasites. Moreover, we also aimed to study the pathological and immunological impacts of trichodinids on fry tissue to improve our understanding of the immune responses of teleost fish to trichodinae parasitic infestations and develop a better control method. Here, we used molecular techniques to identify the isolated trichodina species as T. compacta and demonstrated that Trichodina infestation in Nile tilapia is associated with remarkable immunogenic and inflammatory responses (increased il-1β expression and decreased il-8 and tgf-β expression). These findings improve our understanding of the responses of teleost fish to trichodinid parasite infestation and will be helpful for the development of novel control strategies that reverse the inflammatory and immunogenic alterations that occur in infested fish.

Topics: Animals; Cichlids; DNA, Protozoan; DNA, Ribosomal; Egypt; Fish Diseases; Gills; Host Specificity; Interleukin-1beta; Interleukin-8; Oligohymenophorea; Phylogeny; RNA, Ribosomal, 18S; Skin; Transforming Growth Factor beta

Disease outbreaks with the salmon louse Lepeophtheirus salmonis cause significant economic losses in mariculture operations worldwide. Variable innate immune responses at the louse-attachment site contribute to differences in susceptibility among species such that members of Salmo spp. are more susceptible to infection than those of some Oncorhynchus spp. Relatively little is known about the mechanisms that contribute to disease resistance or susceptibility to L. salmonis in salmon. Here, we utilize histochemistry and transcriptomics in a comparative infection model with susceptible (Atlantic, sockeye) and resistant (coho) salmon. At least three cell populations (MHIIβ+, IL1β+, TNFα+) were activated in coho salmon skin during L. salmonis infection. Locally elevated expression of several pro-inflammatory mediators (e.g. IL1β, IL8, TNFα, COX2, C/EBPβ), and tissue repair enzymes (MMP9, MMP13) were detected in susceptible and resistant species. However, responses specific to coho salmon (e.g. IL4, IL6, TGFβ) or responses shared among susceptible salmon (e.g. SAP, TRF, Cath in Atlantic and sockeye salmon) provide evidence for species-specific pathways contributing to resistance or susceptibility, respectively. Our results confirm the importance of an early pro-inflammatory TH1-type pathway as an initial host response during infection with Pacific sea lice, and demonstrate subsequent regulatory TH2-type processes as candidate defense mechanisms in the skin of resistant coho salmon.

Topics: Animals; Copepoda; Disease Resistance; Disease Susceptibility; Female; Fish Diseases; Gene Expression Regulation; Histocompatibility Antigens Class II; Host-Parasite Interactions; Interleukin-1beta; Interleukin-4; Interleukin-6; Matrix Metalloproteinase 13; Salmo salar; Skin; Species Specificity; TATA Box Binding Protein-Like Proteins; Th1 Cells; Th2 Cells; Transforming Growth Factor beta; Wound Healing

The present study aimed to investigate the effects of Chlorophytum borivilianum polysaccharide (CBP), as a dietary supplement administered at varying concentrations with feed (basal diet), on various cytokine-related responses in Labeo rohita fingerlings. Immune parameters and immune-related gene expressions were measured at 3rd, 4th, and 5th week after feeding. The results revealed that dietary administration of CBP at 0.2% and 0.4% for 4 weeks significantly upregulated serum lysozyme and phagocytic activity. Complement C3 and respiratory burst activity (RBA) were significantly higher after 4 weeks of CBP feeding. The immune related genes IL-8, IL-1β, TNF-α, and iNOS were downregulated (P < 0.05) in groups with 0.2% and 0.4% CBP supplemented diets at week 4. Expression of anti-inflammatory cytokines (IL-10 and TGF-β) was also downregulated (P < 0.5) after 4 weeks of feeding with 0.2% to 0.8% CBP. However, five weeks of CBP administration had no significant effect on immune gene expression, except TNF-α and IL-8. Fish fed with 0.4% CBP for 4 weeks showed maximum resistance against Aeromonas hydrophila (73.3% survival) compared to control. From these results, we recommend that CBP administration at 0.4% for 4 weeks could effectively improve immune response and disease resistance in L. rohita.

Topics: Aeromonas hydrophila; Animal Feed; Animals; Complement C3; Cyprinidae; Dietary Supplements; Disease Resistance; Fish Diseases; Gene Expression Regulation; Gram-Negative Bacterial Infections; Immunity, Innate; Interleukin-10; Interleukin-1beta; Interleukin-8; Liliaceae; Muramidase; Nitric Oxide Synthase Type II; Phagocytosis; Polysaccharides; Respiratory Burst; Survival Analysis; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

The aim of the present study was to assess the prevalence of the flavobacteria within farmed trout and to quantify their bacterial burden. A total of 61 fish were sampled from seven farms, and were distributed in two groups: (1) visibly diseased fish suffering from the rainbow trout fry syndrome or the bacterial cold water disease caused by the bacteria Flavobacterium psychrophilum and (2) normally appearing fish. F. psychrophilum cells were titered by qPCR, targeting a specific area of the 16S rRNA gene in skin, muscle, gills, liver, spleen and kidney from all fish. The pathogen was detected in these organs whatever the health status, with titers ranging from 10(4) to 6 × 10(7)bacteria/g of tissue in normally appearing fish, thus showing they were bacterial carriers. Two organs allowed differentiation between diseased and normally appearing fish: spleen and kidney, with titers ranging from 10(6) to 10(7)bacteria/g of tissue in normally appearing fish vs 10(11) to 10(12)bacteria/g of tissue in diseased fish. No relationship was found between immunoglobulin M-like titer in plasma and health status. Gene expression analysis in fish organs revealed two genes that were markers of the bacterial infection: mt-a and il-1β genes encoding the metallothionein A and the interleukin1-β, respectively. These genes were both over-expressed in gills, liver, spleen and kidney of diseased fish. Four genes encoding immunity markers were down-regulated in spleen (a key organ implicated in immunity) of diseased fish: tgf-β, cd8-α, mhc2-β and igt, suggesting a weakened immune system in diseased fish.

Topics: Animals; Aquaculture; DNA Primers; Down-Regulation; Female; Fish Diseases; Flavobacteriaceae Infections; Flavobacterium; Gene Expression; Immunoglobulin M; Interleukin-1beta; Kidney; Metallothionein; Oncorhynchus mykiss; Prevalence; RNA, Ribosomal, 16S; Spleen; Transforming Growth Factor beta

Small fish models have been used for decades in carcinogenicity testing. Demonstration of common morphological changes associated with specific mechanisms is a clear avenue by which data can be compared across divergent phyletic levels. Dimethylnitrosamine, used in rats to model human alcoholic cirrhosis and hepatic neoplasia, is also a potent hepatotoxin and carcinogen in fish. We recently reported some striking differences in the mutagenicity of DMN in lambda cII transgenic medaka fish vs. Big Blue(®) rats, but the pre-neoplastic and neoplastic commonalities between the two models are largely unknown. Here, we focus on these commonalities, with special emphasis on the TGF-β pathway and its corresponding role in DMN-induced hepatic neoplasia. Similar to mammals, hepatocellular necrosis, regeneration, and dysplasia; hepatic stellate cell and "spindle cell" proliferation; hepatocellular and biliary carcinomas; and TGF-β1 expression by dysplastic hepatocytes all occurred in DMN-exposed medaka. Positive TGF-β1 staining increased with increasing DMN exposure in bile preductular epithelial cells, intermediate cells, immature hepatocytes and fewer mature hepatocytes. Muscle specific actin identified hepatic stellate cells in DMN-exposed fish. Additional mechanistic comparisons between animal models at different phyletic levels will continue to facilitate the interspecies extrapolations that are so critical to toxicological risk assessments.

Topics: Animals; Animals, Genetically Modified; Biliary Tract Neoplasms; Biomarkers; Carcinogenicity Tests; Carcinogens; Carcinoma, Hepatocellular; Cell Proliferation; Chemical and Drug Induced Liver Injury; Dimethylnitrosamine; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Fish Diseases; Liver; Liver Neoplasms; Male; Mutagenicity Tests; Oryzias; Rats; Signal Transduction; Species Specificity; Transforming Growth Factor beta

The rapid doubling time and genetic relatedness of the fish pathogen Mycobacterium marinum to Mycobacterium tuberculosis has rendered the former an attractive model for investigating mycobacterial host-pathogen interactions. We employed the M. marinum-goldfish infection model to investigate the in vivo immune responses to this pathogen in the context of a natural host. Histological analysis revealed mycobacterial infiltrates in goldfish kidney and spleen tissues, peaking 28 days post infections (dpi). Quantitative gene expression analysis showed significant increases of mRNA levels of pro-inflammatory cytokines (IFNγ, IL-12p40, IL-1β1) and cytokine receptors (IFNGR1-1, TNFR2) at 7 dpi. Conversely, the gene expression levels of key anti-inflammatory cytokines TGFβ and IL-10 were elevated at 14 dpi. Furthermore, M. marinum infections markedly increased the cytokine-primed oxidative burst responses of isolated kidney phagocytes at 7 but not 56 dpi. We believe that the M. marinum-goldfish infection model will be invaluable in furthering the understanding of the mycobacterium host-pathogen interface.

Topics: Animals; Disease Models, Animal; Fish Diseases; Gene Expression; Goldfish; Host-Pathogen Interactions; Interferon gamma Receptor; Interferon-gamma; Interleukin-10; Interleukin-12 Subunit p40; Interleukin-1beta; Kidney; Macrophages; Mycobacterium Infections, Nontuberculous; Mycobacterium marinum; Mycobacterium tuberculosis; Phagocytes; Receptors, Interferon; Receptors, Tumor Necrosis Factor, Type II; Respiratory Burst; RNA, Messenger; Spleen; Transforming Growth Factor beta

Topics: Aeromonas hydrophila; Animals; Diet; Dietary Supplements; Fish Diseases; Gene Expression Regulation; Gram-Negative Bacterial Infections; Interleukin-1beta; Interleukin-8; Lupinus; Mangifera; Oncorhynchus mykiss; Transforming Growth Factor beta; Urtica dioica

This study investigated the early expression of T-cell markers and genes potentially involved in the induction of soybean meal (SBM) enteropathy in the distal intestine (DI) of Atlantic salmon (Salmo salar L.). Quantitative PCR was used to study the expression of CD3, CD8beta, transforming growth factor beta (TGF-beta), interferon-gamma-inducible lysosomal thiol reductase (GILT) and interleukin-1beta (IL-1beta) in salmon fed SBM for 1, 3 and 7 days using fish fed fishmeal as controls. In the same tissue, the morphological development of SBM enteropathy was evaluated by routine histology and the presence of T cells was mapped by immunohistochemistry. TGF-beta was significantly down-regulated on all days of feeding SBM. GILT was significantly down-regulated on days 3 and 7 compared to day 1. A depression in the expression of T-cell markers was observed on day 3 whereas increased densities of T cells were observed at the base of mucosal folds after 7 days of feeding SBM. Down-regulation of GILT and TGF-beta may lead to sensitization of intraepithelial lymphocytes and failure to maintain normal mucosal integrity in the DI. These responses are implicated in the pathogenesis of SBM enteropathy in Atlantic salmon.

Topics: Animal Feed; Animals; CD3 Complex; CD8 Antigens; Cloning, Molecular; DNA Primers; Enteritis; Fish Diseases; Gene Expression Regulation; Glycine max; Immunohistochemistry; Interleukin-1beta; Plasmids; Salmo salar; Transforming Growth Factor beta

The development of soybean meal (SBM) induced enteritis in the hindgut of the omnivorous common carp (Cyprinus carpio L.). The developed condition was assessed when carp, continuously fed on animal protein, were transferred to a diet in which 20% of the protein was replaced by SBM. After week 1, most of the inflammation parameters were already present, but at week 3, a strong aggravation of the condition was observed which included a shortening of the mucosal folds, the disappearance of the supranuclear vacuoles, an increased number of goblet cells, a thickened lamina propria and sub-epithelial mucosa with increased numbers of basophilic granulocytes as well as a decreased uptake capacity of enterocytes (impaired endocytosis and microvilli). Contrary to previous observations made with respect to Atlantic salmon, common carp start to recover from the fourth to the fifth week after switching to SBM feeding. At this stage, the supranuclear vacuoles refill and most of the parameters revert to basal levels. During the enteritis process, a real-time quantitative PCR analysis was conducted to measure the expression of inflammatory and anti-inflammatory cytokine genes in the isolated intraepithelial lymphocytes (IEL). The pro-inflammatory interleukin 1 beta (IL-1 beta) and tumour necrosis factor alpha1 (TNF-alpha1) genes were up-regulated during the inflammation process while the anti-inflammatory interleukin 10 (IL-10) was down-regulated after an initial up-regulation at week 1. Transforming growth factor beta (TGF-beta) expression showed an up-regulation from week 3 onwards despite the high Ct value and the low primer efficiency shown. This study confirms the contribution of IEL (mainly T-like cells) and basophils in the enteritis process. In addition, the results show a clear involvement of up- and down-regulated cytokine genes in both the onset and recovery of the SBM-induced enteritis in the hindgut of carp.

Topics: Animals; Carps; Enteritis; Fish Diseases; Gene Expression; Glycine max; Immunohistochemistry; Interleukin-10; Interleukin-1beta; Intestinal Mucosa; Microscopy, Electron; Random Allocation; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Expression of immune-regulatory genes that code for cyclooxigenase-2 (COX-2), transforming growth factor beta (TGF-beta), and two isoforms of interleukin-1beta (IL-1beta1 and IL-1beta2) was studied in susceptible and non-susceptible rainbow trout strains for 200 days after exposure to Myxobolus cerebralis. Expression of COX-2, IL-1beta1, and IL-1beta2 increased 5 min post exposure (p.e.) and was always more elevated in the susceptible strain than in the non-susceptible strain. In both strains, expression of COX-2 returned to the control level within a few hours p.e. Expression of IL-1beta1 and IL-1beta2 showed two elevated waves in both strains until 4 days p.e. Expression of TGF-beta in the non-susceptible strain was elevated at nearly all sampling points, but was decreased in the susceptible strain until up-regulation between 4 and 20 days p.e.; TGF-beta was the only gene where the expression in the non-susceptible strain was more elevated than in the susceptible strain. Rainbow trout of the non-susceptible strain appeared to resist infection by M. cerebralis with only minor transcriptional regulation of the genes investigated. Increased transcriptions of genes in the susceptible strain may be the result of an inability to antagonize the infection.

Topics: Animals; Cyclooxygenase 2; Disease Susceptibility; Eukaryota; Fish Diseases; Gene Expression Regulation; Interleukin-1beta; Oncorhynchus mykiss; Protein Isoforms; Protozoan Infections, Animal; Transforming Growth Factor beta

During the fall of 2001 and 2002, Atlantic menhaden Brevoortia tyrannus were collected from several creeks in the Pamlico River, North Carolina, to investigate recent fish kills and ulcerative skin lesions. High skin lesion prevalence (>50%) was associated with the Atlantic menhaden kills in fall 2001, whereas there were no fish kills in fall 2002 and skin lesion prevalence was lower (< or =50%). Indicators of tissue damage (histopathological analyses of gills, heart, liver, intestine, and anterior kidney), body condition (liver somatic index), and immune status (transforming growth factor-beta [TGF-beta] messenger RNA [mRNA] production, hematology, plasma chemistry, and splenosomatic index) were compared between Atlantic menhaden with and without ulcerative skin lesions in fall. Atlantic menhaden with ulcerative skin lesions had significantly higher liver somatic indices, neutrophil and monocyte percentages, and splenic mononuclear cell TGF-beta mRNA levels than did fish without lesions. Hematocrit values, plasma protein, and Ca concentrations were significantly lower in fish with ulcerative skin lesions than in those without. The indicators used in this study at multiple levels of biological organization have provided valuable baseline data for understanding the health status of lesioned and nonlesioned Atlantic menhaden in the Pamlico River.

Topics: Actins; Animals; Blood Cell Count; Blood Chemical Analysis; Blood Proteins; Fish Diseases; Fishes; Liver; North Carolina; Prevalence; Rivers; Skin; Skin Diseases; Skin Ulcer; Spleen; Transforming Growth Factor beta

Amoebic gill disease (AGD) is an ectoparasitic disease caused by infection with the protozoan Neoparamoeba sp. and is characterised by epithelial hyperplasia that manifests as gill lesions. In order to examine the nature of the immune response to AGD, the expression of a range of immune-regulatory genes was examined in naïve uninfected rainbow trout, Oncorhynchus mykiss, and naïve rainbow trout subjected to a laboratory-induced AGD infection. The immune-regulatory genes examined were interleukin-1 beta isoform 1 (IL-1beta1), tumour necrosis factor alpha isoforms 1 and 2 (TNF-alpha1, TNF-alpha2), interleukin-8 (IL-8), transforming growth factor beta isoform 1 (TGF-beta1), inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), major histocompatibility complex beta chain (MHC-II beta-chain) and T-cell receptor beta chain (TCR beta-chain). Immune-regulatory genes that were up/down-regulated in AGD-infected trout compared to uninfected controls at 0, 7, and 14 days post-inoculation (p.i.) in gill, liver and anterior kidney tissue were initially identified by means of semi-quantitative RT-PCR. Up/down-regulated immune-regulatory genes were subsequently quantitated and validated by real-time RT-PCR (qRT-PCR). The extent of AGD-associated pathology was consistent amongst all AGD-infected trout at 7 days p.i. and increased considerably by 14 days p.i. At both 7 and 14 days p.i. IL-1beta1 and iNOS gene expression was significantly up-regulated in the gills, and IL-8 was significantly up-regulated in the liver of AGD-infected trout at 7 days p.i. These data demonstrate the involvement of the immune response to AGD at the molecular level, and indicate the importance of this response at the site of infection and the possible involvement of a systemic immune response.

Topics: Animals; DNA Primers; Fish Diseases; Gene Expression Regulation; Gills; Interleukin-1; Interleukin-8; Lobosea; Oncorhynchus mykiss; Protozoan Infections; Protozoan Infections, Animal; Reverse Transcriptase Polymerase Chain Reaction; Sequence Analysis, DNA; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

A quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) assay was developed to measure transforming growth factor-beta (TGF-beta) in Atlantic menhaden (Brevoortia tyrannus), an estuarine-dependent species plagued by ulcerative skin lesions in the estuaries along the eastern United States. Atlantic menhaden were acclimated in a closed system for two weeks prior to initiation of the study. The synthetic glucocorticoid, triamcinolone acetonide (10mg/kg body weight) was administered by intracoelomic injection and its effect on the splenic mononuclear cell TGF-beta mRNA transcription, liver-somatic index, spleno-somatic index, hematology, and plasma chemistry were compared to untreated fish at 48 and 96h post-treatment. Triamcinolone-treated Atlantic menhaden showed suppression of TGF-beta mRNA production, neutrophilia, monocytosis, lymphopenia, and an increase in blood glucose concentrations. The health indices used in this study may help us interpret some of the changes observed during the development of ulcerative skin lesions in wild-caught menhaden.

Topics: Animals; Anti-Inflammatory Agents; Base Sequence; Blood Glucose; Fish Diseases; Fishes; Leukocytes, Mononuclear; Liver; Molecular Sequence Data; Plasma; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Skin Ulcer; Spleen; Transforming Growth Factor beta; Triamcinolone Acetonide

Striped bass (Morone saxatilis) and hybrid tilapia (Oreochromis spp.) were experimentally infected with Mycobacterium marinum. Splenic mononuclear cell transforming growth factor-beta (TGF-beta) mRNA was measured by reverse transcription quantitative-competitive PCR (RT-qcPCR). In histologic sections of liver and anterior kidney, the area of each section that was occupied by granulomas and the total area of each section were measured by computer-assisted image analysis and compared as a proportion (the granuloma proportion). Infected striped bass splenic mononuclear cell TGF-beta mRNA expression was significantly lower than uninfected controls, while for tilapia there was no significant difference between infected and control fish. Mycobacterial granuloma proportion of liver and anterior kidney sections was significantly greater for infected striped bass than tilapia. Three (of 10) infected tilapia with the most pronounced inflammatory response displayed a decrease in TGF-beta mRNA expression, similar to the overall striped bass response to mycobacterium challenge. Downregulation of TGF-beta and failure to modulate the immune response may be related to excessive inflammatory damage to organs observed in mycobacteria-sensitive fish species.

Topics: Animals; Bass; Fish Diseases; Gene Expression Regulation; Genetic Predisposition to Disease; Granuloma; Image Processing, Computer-Assisted; Kidney; Liver; Mycobacterium Infections, Nontuberculous; Mycobacterium marinum; Reverse Transcriptase Polymerase Chain Reaction; RNA; Tilapia; Transforming Growth Factor beta