Immunomodulation Evidence of Nanostructured Recombinant Proteins in Salmonid Cells.

Recent studies have demonstrated that immune-related recombinant proteins can enhance immune function, increasing host survival against infectious diseases in salmonids. This research evaluated inclusion bodies (IBs) of antimicrobial peptides (CAMPIB and HAMPIB) and a cytokine (IL1ßIB and TNFαIB) as potential immunostimulants in farmed salmonids. For this purpose, we produced five IBs (including iRFPIB as a control), and we evaluated their ability to modulate immune marker gene expression of three IBs in the RTS11 cell line by RT-qPCR. Additionally, we characterized the scale-up of IBs production by comparing two different scale systems. The results showed that CAMPIB can increase the upregulation of tnfα, il1ß, il8, and il10, HAMPIB significantly increases the upregulation of tnfα, inos, and il10, and IL1ßIB significantly upregulated the expression of tnfα, il1ß, and cox2. A comparison of IL1ßIB production showed that the yield was greater in shake flasks than in bioreactors (39 ± 1.15 mg/L and 14.5 ± 4.08 mg/L), and larger nanoparticles were produced in shake flasks (540 ± 129 nm and 427 ± 134 nm, p < 0.0001, respectively). However, compared with its shake flask counterpart, the IL1ßIB produced in a bioreactor has an increased immunomodulatory ability. Further studies are needed to understand the immune response pathways activated by IBs and the optimal production conditions in bioreactors, such as a defined medium, fed-batch production, and mechanical bacterial lysis, to increase yield.

The immunomodulatory and antioxidant effects of ß-glucans in invertebrates.

ß-glucans (ßGs) are carbohydrate polymers linked by ß-1,3, 1,4 or 1,6 bonds, they have been used to protect against potential pathogens and prevent lethal diseases. The immune system possesses several receptors that identify a wide range of structures and trigger cellular and humoral mechanisms. However, the mechanisms by which ßGs activate the immune system of invertebrate organisms have not been fully clarified. This review is focused on evaluating the effect of ßGs on innate immune system in invertebrates. ßGs stimulate different cellular and humoral mechanisms, such as phagocytosis, oxygen species production, extracellular trap formation, proPO system, and antimicrobial peptide synthesis, moreover, ßGs increase survival rate and decrease pathogen load in several species.

Microbiota plasticity in tilapia gut revealed by meta-analysis evaluating the effect of probiotics, prebiotics, and biofloc.

Tilapia species are among the most cultivated fish worldwide due to their biological advantages but face several challenges, including environmental impact and disease outbreaks. Feed additives, such as probiotics, prebiotics, and other microorganisms, have emerged as strategies to protect against pathogens and promote immune system activation and other host responses, with consequent reductions in antibiotic use. Because these additives also influence tilapia's gut microbiota and positively affect the tilapia culture, we assume it is a flexible annex organ capable of being subject to significant modifications without affecting the biological performance of the host. Therefore, we evaluated the effect of probiotics and other additives ingested by tilapia on its gut microbiota through a meta-analysis of several bioprojects studying the tilapia gut microbiota exposed to feed additives (probiotic, prebiotic, biofloc). A total of 221 tilapia gut microbiota samples from 14 bioprojects were evaluated. Alpha and beta diversity metrics showed no differentiation patterns in relation to the control group, either comparing additives as a group or individually. Results also revealed a control group with a wide dispersion pattern even when these fish did not receive additives. After concatenating the information, the tilapia gut core microbiota was represented by four enriched phyla including Proteobacteria (31%), Fusobacteria (23%), Actinobacteria (19%), and Firmicutes (16%), and seven minor phyla Planctomycetes (1%), Chlamydiae (1%), Chloroflexi (1%), Cyanobacteria (1%), Spirochaetes (1%), Deinococcus Thermus (1%), and Verrucomicrobia (1%). Finally, results suggest that the tilapia gut microbiota is a dynamic microbial community that can plastically respond to feed additives exposure with the potential to influence its taxonomic profile allowing a considerable optimal range of variation, probably guaranteeing its physiological function under different circumstances.

Immunostimulants for preventing respiratory tract infection in children: A systematic review and meta-analysis.

Childhood acute respiratory tract infections (ARTIs) are a significant cause of morbidity and mortality, so, immunostimulants have been used as a preventative measure. Despite this, there is no updated evidence regarding the safety and efficacy of immunostimulant drugs for this purpose. This study aimed to determine the effectiveness and safety of immunostimulants in preventing ARTIs in children based on the most recent scientific evidence. Data sources such as PubMed, Cochrane Central Register of Controlled Trials, Embase, Google Scholar, and Scopus were searched from 1965 to 10 January 2022 to identify randomized controlled trials (RCTs) comparing immunostimulants administered by any method, with placebo to prevent ARTIs on children under 18 years of age without immunodeficiencies, anatomical, genetic, or allergic conditions. In order to analyze data from the studies, we used Review Manager 5.4 (The Cochrane Collaboration, 2020), assessed the certainty of the evidence with Grading of Recommendations, Assessment, Development and Evaluations (GRADE), and assessed the quality and risk of bias of the studies using the RoB tool 1.0. Further, outcomes were combined and analyzed using meta-analysis, subgroup analysis, and sensitivity analysis. Throughout the review, we included 72 placebo-controlled clinical trials involving 12,229 children. The meta-analyses, however, included only 38 studies (52.8%) with 4643 children (38% of the total) with data on mean number of ARTIs. These studies demonstrated a reduction in the ARTIs (MD -1.12 [95%CI -1.39 to -0.85]) and ratio of means of ARTIs (0.61 [95%CI 0.54-0.69]), corresponding to a percentage reduction of 39% (95%CI, 46%-31%) with moderate-quality data. Nevertheless, since there was considerable to substantial heterogeneity and bias was unclear in all domains in 32 out of 72 trials, the quality of the evidence for efficacy was deemed low. Only 14 trials reported adverse events. The review indicates that immunostimulants reduce the incidence of ARTIs by 40% on average in susceptible children, despite low-quality evidence, heterogeneity, and the possibility of publication bias. However, further studies are needed to establish immunostimulants' safety and efficacy profiles. This review was conducted without the support of any funding and has no registered number.

Immunomodulatory effects of Yarrowia lipolytica as a food additive in the diet of Nile tilapia.

The use of yeasts as a dietary additive for fish can act as a source of nutrients and as an immunostimulant. This work aimed to evaluate the effects of the fermented biomass of the yeast Yarrowia lipolytica as a food additive on zootechnical and hematological parameters, and on immune response in the plasma and kidney of Nile Tilapia (Oreochromis niloticus). After supplementation with 3, 5, and 7% of the yeast biomass for 35 days, the blood and tissues of the animals of each experimental group were collected for analysis. The addition of this biomass in the feed promoted an improvement of zootechnical parameters in tilapia. There was also a rise in the number of neutrophils (groups with 3, 5, and 7%) and monocytes (group 3, 5, and 7%) compared with the control group. Moreover, there was an increase in the levels of lysozyme, myeloperoxidase, and nitrite/nitrate content in the blood of animals fed with yeast biomass. On the other hand, there were no observed alterations in survival and hematological parameters of animals fed with yeast biomass. In the analysis of the kidney, the addition of biomass in feed promoted an increase in levels of myeloperoxidase (group with 3%) but did not alter the levels of lysozyme and nitrite/nitrate content. In conclusion, this study demonstrated that Y. lipolytica had growth and immunostimulatory effects on Nile tilapia. These findings strongly suggest the potential application of a Y. lipolytica-based immunostimulant for tilapia aquaculture.

Adjuvants: friends in vaccine formulations against infectious diseases.

Infectious diseases represent a major cause of deaths worldwide. No vaccine or effective treatment exists nowadays, especially against intracellular pathogens. The increase in multiple drug and superbug antibiotic resistance strains, excessive medication, or misuse of drugs has prompted the search for other safe and effective alternatives. Consistent with this, adjuvants (Latin word "adjuvare": "help or aid") co-administered (Exo) in vaccines have emerged as a promising alternative to initiate and boost an innate, downstream signal that led to adaptative immune response. Nowadays, a promising model of strong immunogens and adjuvants at mucosal sites are the microbial bacterial toxins. Other adjuvants that are also used and might successfully replace aluminum salts in combination with nanotechnology are CpG-ODN, poly IC, type I IFNs, mRNA platforms. Therefore, in the present review, we focused to revisit the old to the new adjuvants compounds, the properties that make them friends in vaccine formulations against infectious diseases.

Probiotic and Immunomodulatory Activity of Marine Yeast Yarrowia lipolytica Strains and Response Against Vibrio parahaemolyticus in Fish.

Yarrowia lipolytica has been widely used in food industry but scarcely explored as probiotics. Thus, the aims of this study were to characterize in vitro the probiotic potential, antioxidant capacity, and antimicrobial activity of the marine yeast Y. lipolytica D-1 and N-6 strains. Dietary administration effect was evaluated in vivo on immunological parameters in serum, skin-mucus, intestine, and fish leukocytes upon challenge with Vibrio parahaemolyticus. The results showed that Y. lipolytica D-1 and N-6 strains grew with NaCl or bile salts but were sensitive to low pH. Each of the Y. lipolytica strains had a distinctive antioxidant capacity and fatty acid profile, but their antimicrobial activity was similar against fish bacterial pathogens. Fish (Lutjanus peru) supplemented with Y. lipolytica strains showed normal intestinal morphology, high IgM levels, and antioxidant enzyme activities. Immune-related genes were modulated in fish fed Y. lipolytica in a strain-dependent fashion. In addition, leucocytes from fish fed Y. lipolytica challenged with V. parahaemolyticus increased innate immune and antioxidant parameters compared with the control groups. In conclusion, the marine yeast Y. lipolytica D-1 and N-6 strains may be potential probiotics for fish by exerting free-radical scavenging, antimicrobial activity, and improved immune-protective responses against V. parahaemolyticus infection.

Composition, antioxidant capacity, intestinal, and immunobiological effects of oregano (Lippia palmeri Watts) in goats: preliminary in vitro and in vivo studies.

This study investigated Lippia palmeri Watt (oregano) phytochemical compounds, their antioxidant capacity, and immunological effects on goat peripheral blood leukocytes (PBL), and on the presence of intermediate polar compounds in goat feces fed dietary oregano. The polar and nonpolar fractions of L. palmeri W. were characterized and phytochemical contents and antioxidant capacity were determined. Twelve healthy Anglo-Nubian goats were used for the in vivo trials, which were randomly assigned to control fed with basal diet, or oregano group fed with basal diet + 2.6% (DM basis) dried oregano leaves. Goat peripheral blood leukocytes (PBL) were isolated for the in vitro study, and PBL were stimulated with oregano extracts at 100 and 150 µg/mL after 24 h. For the in vivo trial, dietary oregano (2.6% on DM basis) was evaluated in the goats for 90 days. Relatively high abundance of carvacrol and thymol phytochemical compounds was found in oregano. The highest antioxidant capacity of oregano extracts was detected at 100 and 150 µg/mL. Nitric oxide production, phagocytosis, and superoxide dismutase activities increased (p < 0.05) in stimulated PBL with oregano extracts, whereas the pro-inflammatory (TNF-α and IL-1ß) transcription and antioxidant (CAT and GPX-4) genes downregulated. In the in vivo experiment, dietary oregano enabled the detection of nine compounds found in goat feces, from which caproic (C6) was in a high relative quantity compared with the control group. Oregano has phytochemical compounds with strong antioxidant capacity that protect cells against oxidative stress damage and could modulate immune response and feces composition in goats.

Gemini lipopeptides as vaccine adjuvants: a new role for these versatile carriers.

The design of subunit vaccines requires new adjuvant systems. We designed and synthesized new lipopeptides (cysteine-based) of low molecular weight with different hydrophobic chains that dimerize becoming gemini lipopeptides. They were characterized and their adjuvant capacity was tested in mice by the inoculation of a protein antigen formulated with the lipopeptides, with and without the addition of CpG-oligodeoxynucleotides. Formulations were able to induce an immune response and produced no adverse effects. An adjuvant ability is described for the first time for this type of molecules.

Exploitation of Agro-Industrial Waste as Potential Source of Bioactive Compounds for Aquaculture.

The agroindustry generates a large amount of waste. In postharvest, food losses can reach up to 50%. This waste represents a source of contamination of soil, air, and bodies of water. This represents a problem for the environment as well as for public health. However, this waste is an important source of bioactive compounds, such as phenolic compounds, terpenes, and ß-glucans, among others. Several biological activities have been attributed to these compounds; for example, antioxidant, antimicrobial, gut microbiota, and immune system modulators. These properties have been associated with improvements in health. Recently, the approach of using these bioactive compounds as food additives for aquaculture have been addressed, where it is sought that organisms, in addition to growing, preserve their health and become disease resistant. The exploitation of agro-industrial waste as a source of bioactive compounds for aquaculture has a triple objective-to provide added value to production chains, reduce pollution, and improve the well-being of organisms through nutrition. However, to make use of the waste, it is necessary to revalue them, mainly by determining their biological effects in aquaculture organisms. The composition of bioactive compounds of agro-industrial wastes, their biological properties, and their application in aquaculture will be addressed here.

Gold nanoparticles (AuNP) exert immunostimulatory and protective effects in shrimp (Litopenaeus vannamei) against Vibrio parahaemolyticus.

Gold nanoparticles (AuNP) stimulate immune responses in mammals but they have not been tested in species of relevance in aquaculture. In this study the immunostimulant and protective potential of orally administered AuNP against V. parahaemolyticus, the causative agent of Acute Hepatopancreatic Necrosis Disease, was determined in shrimp. Synthetized AuNP (18.57 ±â€¯4.37 nm) were moderately dispersed with a negative ζ potential of -10.3 ±â€¯0.208 mV (pH = 7). AuNP were administered (single dose) at 0.2, 2, and 20 µg/g feed in shrimp. Hemolymph samples were withdrawn daily for 6 days. Hemolymph or hemocytes were used to determine total hemocyte counts, immune-related enzymatic activities, and expression of immune-relevant genes. Hepatopancreas was sampled for the analysis of AuNP biodistribution and histological examination. Survival was recorded daily. No mortality or toxicity signs in hepatopancreas were found. AuNP were detected in hepatopancreas. Early (24-48 h) immunostimulation was mainly related to immune gene up-regulation. Upon a challenge with V. parahaemolyticus, survival was higher (80%) and histopathological damages were lower in shrimp treated with the 2 µg/g dose when compared to the control. Therefore orally administered AuNP are proposed as immunostimulants that protect shrimp against V. parahaemolyticus infection.

Effect of Argemone mexicana active principles on inhibiting viral multiplication and stimulating immune system in Pacific white leg shrimp Litopenaeus vannamei against white spot syndrome virus.

Argemone mexicana called as Mexican prickly poppy is a species of poppy found in Mexico and now widely naturalized in many parts of the world with broad range of bioactivities including anthelmintic, cures lepsory, skin-diseases, inflammations and bilious fevers. Plant parts of A. mexicana were serially extracted with hexane, ethyl acetate, methanol and performed antiviral and immunostimulant screening against WSSV and Vibrio harveyi respectively. The control groups succumbed to death 100% within three days, whereas the mortality was significantly (P < 0.5) reduced to 17.43 and 7.11 in the ethyl acetate extracts of stem and root treated shrimp group respectively. The same trend was reflected in the immunostimulant screening also. Different diets were prepared by the concentrations of 100 (AD-1), 200 (AD-2), 300 (AD-3) and 400 (AD-4) mg kg-1 using A. mexicana stem and root ethyl acetate extracts and fed to Pacific white leg shrimp Litopenaeus vannamei weighed about 9.0 ±â€¯0.5 g for 30 days. The control groups fed with the normal diets devoid of A. mexicana extracts. The antiviral screening results revealed that, the ethyl acetate extract of the stem and root were effectively suppressed the WSSV and it reflected in the lowest cumulative mortality of treated shrimps. After termination of feeding trials, group of shrimps from control and each experimental group were challenged with virulent WSSV by intramuscular (IM) injection and studied cumulative mortality, molecular diagnosis by quantitative real time PCR (qRT-PCR), biochemical, haematological and immunological parameters. Control group succumbed to 100% death within four days, whereas the survival was significantly (P < 0.001) increased to 30, 45, 75 and 79% in AD1, AD-2, AD-4 and AD-5 diets fed shrimp groups respectively. qRT PCR results with positive correlation analysis revealed that, the WSSV copies were gradually decreased when increasing the A. mexicana extracts in the diets. The highest concentrations (300 and 400 mg g-1) of A. mexicana extracts in the diets helped to reduce the protein level significantly (P < 0.05) after WSSV challenge. The diets AD-3 and AD-4 also helped to decrease the coagulation time of maximum 64-67% from control groups and maintained the normal level of total haemocyte, oxyhaemocyanin level after WSSV challenge. The proPO level was significantly increased (Column: F = 35.93; P ≤ 0.001 and Row: F = 37.14; P ≤ 0.001) in the AD1-AD-4 diet fed groups from the control diet fed groups. The lowest intra-agar lysozyme activity of 1.63 mm found in control diet fed group and the activity were significantly (P < 0.05) increased to 4.86, 7.89, 9.12 and 10.45 mm of zone of inhibition respectively in AD1 to AD4 diet fed groups.

Immunomodulatory effects of dietary Beta-glucan in silver catfish (Rhamdia quelen) / Efeito imunomodulador da Beta- glucana usada como aditivo alimentar em jundiás (Rhamdia quelen)

The immunomodulatory effects of dietary Beta-glucan were evaluated in silver catfish. Beta-glucan was added to the diet (0.01%, and 0.1%) and fed to the fish for 21 days, to evaluate effects on blood and some innate immune parameter, or fed for 42 days, to evaluate growth rate and resistance to challenge with pathogenic Aeromonas hydrophila. We found that adding Beta-glucan to the diet had no effect on fish growth and no effect on blood cells, or serum bacterial agglutination and serum myeloperoxidase activity. However, fish that received Beta-glucan in the diet had the natural hemolytic activity of complement significantly higher compared to control fish. Furthermore, fish fed with Beta-glucan and challenged with A. hydrophila had fewer bacteria in blood and presented a significantly higher survival rate compared to control fish. Thus, we concluded that Beta-glucan might be explored as feed additive aiming to improve silver catfish innate immunity and resistance to specific pathogen.(AU)

O uso da Beta-glucana como suplemento alimentar foi avaliado em jundiás. A Beta-glucana foi adicionada à ração na proporção de 0.01%, e 0.1% e fornecida aos peixes por 21, para avaliar dados hematológicos e parâmetros do sistema imune natural, ou 42 dias, para avaliar ganho de peso e resistência ao desafio com Aeromonas hydrophila. A adição da Beta-glucana na dieta não afetou o ganho de peso e não induziu alterações hematológicas nem alterações nos níveis de aglutininas e mieloperoxidase sanguínea. No entanto, a atividade hemolítica natural do sistema do complemento foi significativamente maior nos peixes alimentados com Beta-glucana. Além disso, nos peixes alimentados com Beta-glucana e desafiados com A. hydrophila, o número de bactérias isoladas do sangue foi significativamente menor, e a sobrevivência ao desafio foi significativamente maior do que nos peixes que não receberam Beta-glucana. Consequentemente, concluímos que a Beta-glucana tem potencial imunomodulador quando adicionada à dieta, nas condições experimentais aqui indicadas, e contribui para aumentar imunidade natural e a resistência dos jundiás ao desafio com patógenos específicos.(AU)

Immunomodulatory effects of dietary ß-glucan in silver catfish (Rhamdia quelen) / Efeito imunomodulador da ß-glucana usada como aditivo alimentar em jundiás (Rhamdia quelen)

The immunomodulatory effects of dietary ß-glucan were evaluated in silver catfish. ß-glucan was added to the diet (0.01%, and 0.1%) and fed to the fish for 21 days, to evaluate effects on blood and some innate immune parameter, or fed for 42 days, to evaluate growth rate and resistance to challenge with pathogenic Aeromonas hydrophila. We found that adding ß-glucan to the diet had no effect on fish growth and no effect on blood cells, or serum bacterial agglutination and serum myeloperoxidase activity. However, fish that received ß-glucan in the diet had the natural hemolytic activity of complement significantly higher compared to control fish. Furthermore, fish fed with ß-glucan and challenged with A. hydrophila had fewer bacteria in blood and presented a significantly higher survival rate compared to control fish. Thus, we concluded that ß-glucan might be explored as feed additive aiming to improve silver catfish innate immunity and resistance to specific pathogen.(AU)

O uso da ß-glucana como suplemento alimentar foi avaliado em jundiás. A ß-glucana foi adicionada à ração na proporção de 0.01%, e 0.1% e fornecida aos peixes por 21, para avaliar dados hematológicos e parâmetros do sistema imune natural, ou 42 dias, para avaliar ganho de peso e resistência ao desafio com Aeromonas hydrophila. A adição da ß-glucana na dieta não afetou o ganho de peso e não induziu alterações hematológicas nem alterações nos níveis de aglutininas e mieloperoxidase sanguínea. No entanto, a atividade hemolítica natural do sistema do complemento foi significativamente maior nos peixes alimentados com ß-glucana. Além disso, nos peixes alimentados com ß-glucana e desafiados com A. hydrophila, o número de bactérias isoladas do sangue foi significativamente menor, e a sobrevivência ao desafio foi significativamente maior do que nos peixes que não receberam ß-glucana. Consequentemente, concluímos que a ß-glucana tem potencial imunomodulador quando adicionada à dieta, nas condições experimentais aqui indicadas, e contribui para aumentar imunidade natural e a resistência dos jundiás ao desafio com patógenos específicos.(AU)

Immunomodulatory effects of dietary -glucan in silver catfish (Rhamdia quelen)

ABSTRACT: The immunomodulatory effects of dietary -glucan were evaluated in silver catfish. -glucan was added to the diet (0.01%, and 0.1%) and fed to the fish for 21 days, to evaluate effects on blood and some innate immune parameter, or fed for 42 days, to evaluate growth rate and resistance to challenge with pathogenic Aeromonas hydrophila. We found that adding -glucan to the diet had no effect on fish growth and no effect on blood cells, or serum bacterial agglutination and serum myeloperoxidase activity. However, fish that received -glucan in the diet had the natural hemolytic activity of complement significantly higher compared to control fish. Furthermore, fish fed with -glucan and challenged with A. hydrophila had fewer bacteria in blood and presented a significantly higher survival rate compared to control fish. Thus, we concluded that -glucan might be explored as feed additive aiming to improve silver catfish innate immunity and resistance to specific pathogen.

RESUMO: O uso da -glucana como suplemento alimentar foi avaliado em jundiás. A -glucana foi adicionada à ração na proporção de 0.01%, e 0.1% e fornecida aos peixes por 21, para avaliar dados hematológicos e parâmetros do sistema imune natural, ou 42 dias, para avaliar ganho de peso e resistência ao desafio com Aeromonas hydrophila. A adição da -glucana na dieta não afetou o ganho de peso e não induziu alterações hematológicas nem alterações nos níveis de aglutininas e mieloperoxidase sanguínea. No entanto, a atividade hemolítica natural do sistema do complemento foi significativamente maior nos peixes alimentados com -glucana. Além disso, nos peixes alimentados com -glucana e desafiados com A. hydrophila, o número de bactérias isoladas do sangue foi significativamente menor, e a sobrevivência ao desafio foi significativamente maior do que nos peixes que não receberam -glucana. Consequentemente, concluímos que a -glucana tem potencial imunomodulador quando adicionada à dieta, nas condições experimentais aqui indicadas, e contribui para aumentar imunidade natural e a resistência dos jundiás ao desafio com patógenos específicos.

ß-1,3/1,6-Glucan-supplemented diets antagonize immune inhibitory effects of hypoxia and enhance the immune response to a model vaccine.

The diets of farmed salmon are usually supplemented with immunostimulants to improve health status. Because ß-glucan is one of the most common immunostimulants used in diets, here we examined the effect of two ß-1,3/1,6-glucan-supplemented diets on the expression of immune response genes of Atlantic salmon. The relative abundances of IFN-α1, Mx, IFN-γ, IL-12, TGF-ß1, IL-10, and CD4 transcripts were evaluated in head kidney by qRT-PCR. We assessed the effects of the diets under normoxia and acute hypoxia, as salmon are especially sensitive to changes in the concentration of dissolved oxygen, which can also affect immunity. These effects were also tested on vaccinated fish, as we expected that ß-1,3/1,6-glucan-supplemented diets would enhance the adaptive immune response to the vaccine. We found that administration of the Bg diet (containing ß-1,3/1,6-glucan) under normoxia had no effects on the expression of the analyzed genes in the kidney of the diet-fed fish, but under hypoxia/re-oxygenation (90 min of acute hypoxia), the ßg diet affected the expression of the antiviral genes, IFN-α1 and Mx, preventing their decrease caused by hypoxia. The Bax diet, which in addition to ß-1,3/1,6-glucan, contained astaxanthin, increased IL-12 and IFN-γ in kidneys. With fish exposed to hypoxia/reoxygenation, the diet prevented the decrease of IFN-α1 and Mx levels observed after hypoxia. When fish were vaccinated, only the levels of IL-12 and CD4 transcripts increased, but interestingly if fish were also fed the Bax diet, the vaccination induced a significant increase in all the analyzed transcripts. Finally, when vaccinated fish were exposed to hypoxia, the effect of the Bax diet was greatly reduced for all genes tested and moreover, inducible effects completely disappeared for IL-12, IFN-α, and Mx. Altogether, these results showed that the tested ß-1,3/1,6-glucan diets increased the levels of transcripts of key genes involved in innate and adaptive immune response of salmon, potentiating the response to a model vaccine and also antagonizing the effects of hypoxia.

Probiotics, immunostimulants, plant products and oral vaccines, and their role as feed supplements in the control of bacterial fish diseases.

There is a rapidly increasing literature pointing to the success of probiotics, immunostimulants, plant products and oral vaccines in immunomodulation, namely stimulation of the innate, cellular and/or humoral immune response, and the control of bacterial fish diseases. Probiotics are regarded as live micro-organisms administered orally and leading to health benefits. However, in contrast with the use in terrestrial animals, a diverse range of micro-organisms have been evaluated in aquaculture with the mode of action often reflecting immunomodulation. Moreover, the need for living cells has been questioned. Also, key subcellular components, including lipopolysaccharides, have been attributed to the beneficial effect in fish. Here, there is a link with immunostimulants, which may also be administered orally. Furthermore, numerous plant products have been reported to have health benefits, namely protection against disease for which stimulation of some immune parameters has been reported. Oral vaccines confer protection against some diseases, although the mode of action is usually linked to humoral rather than the innate and cellular immune responses. This review explores the relationship between probiotics, immunostimulants, plant products and oral vaccines.

Production of recombinant immunotherapeutics for anticancer treatment: the role of bioengineering.

Cancer is one of the most important health problems because many cases are difficult to prevent. Cancer still has unknown mechanisms of pathogenesis, and its capacity to produce temporary or permanent damage, besides death, is very high. Although many anticancer therapies are available, finding a cure for cancer continues to be a difficult task. Thus, many efforts have been made to develop more effective treatments, such as immunotherapy based on a new class of tumor-specific products that are produced using recombinant DNA technology. These recombinant products are used with the main objectives of killing the tumor and stimulating immune cells to respond to the cancer cells. The principal recombinant products in anticancer therapy are immunostimulants, vaccines, antibodies, immunotoxins and fusion proteins. This review focuses on the general aspects of these genetically engineered products, their clinical performance, current advances and future prospects for this type of anticancer therapy.