Antineoplastic treatment class modulates COVID-19 mRNA-BNT162b2 vaccine immunogenicity in cancer patients: a secondary analysis of the prospective Vax-On study.

BACKGROUND: Preliminary analysis from the Vax-On study did not find a correlation between cancer treatment type and antibody response to COVID-19 vaccination. We carried out a secondary subgroup analysis to verify the effects of comprehensive cancer treatment classification on vaccine immunogenicity. METHODS: The Vax-On study prospectively enrolled patients who started a two-dose messenger RNA-BNT162b2 vaccine schedule from 9 March 2021 to 12 April 2021 (timepoint-1). Those on active treatment within the previous 28 days accounted for the exposed cases. Patients who had discontinued such treatment by at least 28 days or received intravesical therapy represented the control cases. Quantification of immunoglobulin G (IgG) antibodies against the receptor binding domain of the S1 subunit of the SARS-CoV-2 spike protein was carried out before the second dose (timepoint-2) and 8 weeks thereafter (timepoint-3). Seroconversion response was defined at ≥50 arbitrary units/ml IgG titer. Classification of antineoplastic agents was based on their pharmacodynamic properties. RESULTS: Three hundred and sixty-six patients were enrolled (86 and 260 as control and exposed cases, respectively). Univariate analysis revealed a significantly lower IgG titer after both doses of vaccine in subgroups treated with tyrosine kinase inhibitors (TKIs), multiple cytotoxic agents, alkylating agents, and topoisomerase inhibitors. At timepoint-3, seroconversion response was significantly impaired in the topoisomerase inhibitors and mechanistic target of rapamycin (mTOR) inhibitors subgroups. After multivariate testing, treatment with alkylating agents and TKIs was significantly associated with a reduced change in IgG titer at timepoint-2. Treatment with mTOR inhibitors resulted in a similar interaction at each timepoint. Cyclin-dependent kinase 4/6 inhibitor treatment was independently correlated with an incremental variation in IgG titer at timepoint-3. Specific subgroups (TKIs, antimetabolites, alkylating agents, and multiple-agent chemotherapy) predicted lack of seroconversion at timepoint-2, but their effect was not retained at timepoint-3. Eastern Cooperative Oncology Group performance status 2, immunosuppressive corticosteroid dosing, and granulocyte colony-stimulating factor use were independently linked to lower IgG titer after either dose of vaccine. CONCLUSIONS: Drugs interfering with DNA synthesis, multiple-agent cytotoxic chemotherapy, TKIs, mTOR and cyclin-dependent kinase 4/6 inhibitors differentially modulate humoral response to messenger RNA-BNT162b2 vaccine.

Pattern-Recognition Receptor Agonist-Containing Immunopotentiator CVC1302 Boosts High-Affinity Long-Lasting Humoral Immunity.

Ideally, a vaccine should provide life-long protection following a single administered dose. In our previous study, the immunopotentiator CVC1302, which contains pattern- recognition receptor (PRR) agonists, was demonstrated to prolong the lifetime of the humoral immune response induced by killed foot-and-mouth disease virus (FMDV) vaccine. To elucidate the mechanism by which CVC1302 induces long-term humoral immunity, we used 4-hydroxy-3-nitrophenylacetyl (NP)-OVA as a pattern antigen and administered it to mice along with CVC1302, emulsified together with Marcol 52 mineral oil (NP-CVC1302). From the results of NP-specific antibody levels, we found that CVC1302 could induce not only higher levels of NP-specific antibodies but also high-affinity NP-specific antibody levels. To detect the resulting NP-specific immune cells, samples were taken from the injection sites, draining lymph nodes (LNs), and bone marrow of mice injected with NP-CVC1302. The results of these experiments show that, compared with mice injected with NP alone, those injected with NP-CVC1302 had higher percentages of NP+ antigen-presenting cells (APCs) at the injection sites and draining LNs, higher percentages of follicular helper T cells (TFH), germinal center (GC) B cells, and NP+ plasma-blasts in the draining LNs, as well as higher percentages of NP+ long-lived plasma cells (LLPCs) in the bone marrow. Additionally, we observed that the inclusion of CVC1302 in the immunization prolonged the lifetime of LLPCs in the bone marrow by improving the transcription expression of anti-apoptotic transcription factors such as Mcl-1, Bcl-2, BAFF, BCMA, Bax, and IRF-4. This research provides a blueprint for designing new generations of immunopotentiators.

Effect of methanolic extract of Citrus limetta peel on cellular and humoral immune response in mice.

Citrus limetta is well known for its anti-inflammatory, antimicrobial, antifungal, antidiabetic and antioxidant properties. Methanolic extract of Citrus limetta (MECL) was used to assess cellular and humoral immune responses in mice by carrying out cyclophosphamide-induced neutropenia, delayed-type hypersensitivity (DTH), carbon clearance assay, haemagglutination assay (HA) and mice lethality assay. Methanolic extract of Citrus limetta peel was administered orally to mice in two doses 200mg/kg and 400mg/kg.The extract treated groups showed improvement in neutropenia induced by cyclophosphamide and improvement in the WBC profile. Skin thickness was significantly (P<0.05) higher in 200mg/kg and 400mg/kg groups in comparison to control in DTH. The phagocytic index was significantly (P<0.05) more in 400mg/kg group in carbon clearance assay. Mice were vaccinated with hemorrhagic septicemia vaccine before challenge with Pasteurella multocida for mice lethality test. Percentage mortality was decreased in 400mg/kg treated group in comparison to negative control Antibody titre response to sheep red blood cells was significantly (P<0.05) higher with dose 400mg/kg in HA. Results suggested the effectiveness of the methanolic extract of Citrus limetta as an immunostimulating agent.

Small-molecule polymerase inhibitor protects non-human primates from measles and reduces shedding.

Measles virus (MeV) is a highly contagious pathogen that enters the human host via the respiratory route. Besides acute pathologies including fever, cough and the characteristic measles rash, the infection of lymphocytes leads to substantial immunosuppression that can exacerbate the outcome of infections with additional pathogens. Despite the availability of effective vaccine prophylaxis, measles outbreaks continue to occur worldwide. We demonstrate that prophylactic and post-exposure therapeutic treatment with an orally bioavailable small-molecule polymerase inhibitor, ERDRP-0519, prevents measles disease in squirrel monkeys (Saimiri sciureus). Treatment initiation at the onset of clinical signs reduced virus shedding, which may support outbreak control. Results show that this clinical candidate has the potential to alleviate clinical measles and augment measles virus eradication.

GAS1: A New ß-Glucan Immunostimulant Candidate to Increase Rainbow Trout (Oncorhynchus mykiss) Resistance to Bacterial Infections With Aeromonas salmonicida achromogenes.

ß-glucans are prebiotic and/or food additives used by the aquaculture industry to enhance the immune response of fish. Their efficiency may vary according to their origin and structure. In this study, the immunostimulant effects of two ß-glucan types extracted from wild-type baker's yeast (Saccharomyces cerevisiae) and its null-mutant Gas1 were investigated. Gas1 has a beta-1,3-glucanosyltransferase activity necessary for cell wall assembly. Using a positive (commercial product MacroGard®) and a negative control (a diet without glucans), we evaluated the immune responses and disease resistance of rainbow trout juveniles (mean weight, ~44 g) fed control, low (0.2%) and high (0.5%) doses of Macrogard®, Gas1, and Wild type-ß-glucan after a short-term (15 days, D15) or mid-term (36 days, D36) feeding periods. We found that ß-glucan supplemented diets did not affect growth performance, mortality, splenic index, or leukocyte respiratory burst activity on D15 nor D36. However, each ß-glucan triggered different immune effectors, depending of the doses or length of exposure compared to others and/or the negative control. Indeed, high dose of MacroGard® significantly increased lysozyme activities at D15 compared with the control and other diets (p<0.05). At D36, MacroGard ß-glucan enhanced the production of lymphocytes in comparison with the control diet (p<0.05). Regarding WT ß-glucan, at D36, WT-ß-glucan, especially the high dose, provided the highest enzymatic activities (lysozyme and ACH50) and Ig level (p<0.01). Furthermore, on D36, Gas1 also increased lysozyme activity, Ig proportion, and some immune genes (mcsfra, hepcidin) compared with MacroGard® (p<0.05). Besides, both doses of Gas1-ß-glucans increased the resistance of juveniles to bacterial infection highlighted by a higher survival rate at 14 days post-challenge compared with the control and other types and doses of ß-glucans (p<0.05). In conclusion, our results suggest that Gas1-ß-glucan could represent a promising immunostimulant that would help to prevent diseases in aquaculture even more efficiently than other ß-glucans already in use. Mode of action and particular efficiency of this new Gas1 mutant are debated.

Evaluation of Th1 and Th2 mediated cellular and humoral immunity in patients with COVID-19 following the use of melatonin as an adjunctive treatment.

Coronavirus (SARS-CoV-2) is spreading rapidly in the world and is still taking a heavy toll. Studies show that cytokine storms and imbalances in T-helper (Th)1/Th2 play a significant role in most acute cases of the disease. A number of medications have been suggested to treat or control the disease but have been discontinued due to their side effects. Melatonin, as an intrinsic molecule, possesses pharmacological anti-inflammatory and antioxidant properties that decreases in concentration with age; as a result, older people are more prone to various diseases. In this study, patients who were hospitalized with a diagnosis of coronavirus disease 2019 (COVID-19) were given a melatonin adjuvant (9 mg daily, orally) for fourteen days. In order to measure markers of Th1 and Th2 inflammatory cytokines (such as interleukin (IL)-2, IL-4, and interferon (IFN)-γ) as well as the expression of Th1 and Th2 regulatory genes (signal transducer and activator of transcription (STAT)4, STAT6, GATA binding protein 3 (GATA3), and T-box expressed in T cell (T-bet)), blood samples were taken from patients at the beginning and end of the treatment. Adjuvant therapy with melatonin controlled and reduced inflammatory cytokines in patients with COVID-19. Melatonin also controlled and modulated the dysregulated genes that regulate the humoral and cellular immune systems mediated by Th1 and Th2. In this study, it was shown for the first time that melatonin can be used as a medicinal adjuvant with anti-inflammatory mechanism to reduce and control inflammatory cytokines by regulating the expression of Th1 and Th2 regulatory genes in patients with COVID-19.

Immunization with recombinant protein Ag43::UpaH with alum and 1,25(OH)2D3 adjuvants significantly protects Balb/C mice against urinary tract infection caused by uropathogenic Escherichia coli.

The majority of urinary tract infections (UTIs) are caused by uropathogenic Escherichia coli (UPEC). Designing a vaccine will certainly reduce the occurrence of infection and antibiotic resistance of the isolates. Antigen 43 (Ag43) and autotransporter H (UpaH) have been associated with the virulence of UPEC. In the present study, the efficacy of different formulations of a hybrid protein composed of Ag43 and UpaH with and without alum and 1,25(OH)2D3 (Vitamin D3) adjuvants were evaluated in mice model. A significant increase in IgG and cellular responses was developed against Ag43::UpaH as compared to the control mice. The addition of alum or a mixture of alum and Vitamin D3 to the protein significantly enhanced the serum IgG responses and tended to remain in a steady state until 6 months. In addition, the mentioned formulations produced significant amounts of IgG1, IL-4, and IL-17 as compared to the fusion protein alone. In addition to the mentioned formulations, the combination of protein with Vitamin D3 also resulted in significantly higher serum IgA and IFN-γ levels as compared to the fusion protein alone. Mice immunized with fusion plus alum and formulation protein admixed with both alum and Vitamin D3 significantly reduced the bacterial load in the bladders and kidneys of mice as compared to the control. In this study, for the first time, the ability of a novel hybrid protein in combination with adjuvants alum and Vitamin D3 was evaluated against UPEC. Our results indicated that fusion Ag43::UpaH admixed with alum and Vitamin D3 could be a promising candidate against UTIs.

A purified acidic polysaccharide from Sarcandra glabra as vaccine adjuvant to enhance anti-tumor effect of cancer vaccine.

Immunological adjuvants are an important part of tumor vaccines and are critical for stimulating anti-tumor immune responses. However, the clinical needs of strong adjuvants have not been met. In this work, we found that the purified acidic polysaccharide from Sarcandra glabra, named p-SGP, is an ideal adjuvant for tumor vaccines. Cancer vaccines could induce stronger humoral and cellular immune responses when they are adjuvanted with p-SGP. Compared with CpG, a well-studied adjuvant, p-SGP significantly augmented the anti-tumor immunity of various cancer vaccines, which is leading to noticeable inhibition of tumor growth and metastasis in tumor-bearing mice. Moreover, p-SGP promoted dendritic cells (DCs) maturation and Th1-polarized immune response. Toll-like receptor 4 (TLR4) inhibitor TAK-242 could significantly inhibit the expression of mature molecules on the surface of DCs stimulated by p-SGP, suggesting that p-SGP could play the role of activating DCs through the TLR4 receptor. Results of RNA-seq showed that the Delta-like ligand 4 (DLL4) gene in the pathway Th1 and Th2 cell differentiation was significantly up-regulated in the DCs treated with p-SGP, suggesting that p-SGP has a unique mechanism of enhancing anti-tumor immunity.

Immunosuppressive activity of daphnetin on the humoral immune responses in ovalbumin-sensitized BALB/c mice.

INTRODUCTION: Most of the immunosuppressive drugs are used for the treatment of autoimmune disease, allergic diseases, and transplant rejection, but toxicity is the major obstacle for the potent drugs in the wide use of these immunosuppressive drugs. Daphnetin, a Chinese herbal product, has been reported that daphnetin possesses antimicrobial, anticoagulation, antimalarial, anticancer, and antioxidant activity. In a previous study, we found that daphnetin exhibited a potential immunosuppressive effect on LPS-induced B lymphocyte cells in vitro, therefore, in this research, we investigated the immunosuppressive effects of daphnetin in BALB/c mice use OVA as a prototype antigen. METHODS: Sixty BALB/c mice were divided into six groups. The emulsion (100 µL containing 100 µg OVA) was injected subcutaneously with OVA + CFA into the shaved backs of the BALB/c mice on day 1, and a boosting injection was administered in OVA + IFA 2 weeks later. Beginning on the day of immunization, the immunized mice were administered intraperitoneally with daphnetin at a dose of 5, 10, and 20 mg/kg in saline solution for 28 consecutive days. We measured the effect of daphnetin on OVA-specific antibody, cytokine production, and Splenocyte proliferation in vivo. RESULTS: The results revealed that daphnetin significantly suppressed serum immunoglobulin G levels (IgG), and the OVA-specific IgG subclasses IgG1 and IgG2b, daphnetin was also significantly decreased the Th1 and Th2 cytokine productions, inhibited the splenocytes proliferation rate in vivo. CONCLUSIONS: It proved that daphnetin could suppress humoral response activity on OVA-sensitized mice, suggesting a potential role on daphnetin as a new immunosuppressive drug.

Influence of Nigerian Jelly Ear Culinary-Medicinal Mushroom, Auricularia auricula-judae (Agaricomycetes), on Humoral and Cellular Immunity.

The fruiting body of Auricularia auricula-judae has received attention in folk medicine due to its possible medicinal values. Therefore, this study evaluated the immunomodulatory effects of the hot aqueous extract (AAAJ) and the ß-D-glucan-rich polysaccharide fraction of A. auricula-judae (BGPA) on specific and nonspecific humoral and cell mediated immune responses in immunocompetent and immunosuppressed mice. Oral supplementation with AAAJ or BGPA (100, 200, or 400 mg/kg) produced significantly high titers of total OVA specific or TT specific IgG1 and IgG2a compared with the levels in untreated control. Oral administration of AAAJ or BGPA (100, 200, or 400 mg/kg) evoked a significant increase in carbon clearance at all doses, indicating stimulation of the reticuloendothelial system, and potentiated the delayed-type hypersensitivity reaction induced by sheep red blood cells (SRBC) compared with the untreated mice. Total lymphocyte count, neutrophil count, and lymphocytes count increased significantly (P < 0.05) at all doses, following acute administration of AAAJ or BGPA (100, 200, or 400 mg/kg), showing increased protection toward cyclophosphamide induced myelosuppression compared with the untreated negative control group. In the hemolytic complement assay, AAAJ and BGPA at all doses significantly (P < 0.05) inhibited the hemolytic activity of the complement proteins on the sensitized SRBC. The present study reveals that the extract holds promise as an immunomodulatory agent and strengthens the rationale for its use in traditional medicine.

Dietary supplementation of marine yeast Yarrowia lipolytica modulates immune response in Litopenaeus vannamei.

The immunostimulatory potential of the marine yeast Yarrowia lipolytica (D1 and N6 strains) administered orally was evaluated in the white shrimp Litopenaeus vannamei. Yeasts and commercial glucans were mixed with a commercial feed to formulate diets with a 1.1% concentration of immunostimulants. The shrimp were fed daily for a period of 21 days. Weekly determinations were performed for immunological parameters in hemolymph, such as total hemocyte count (THC), lysozyme activity (LYZ), prophenoloxidase activity, antioxidant enzymatic activities (superoxide dismutase [SOD], catalase [CAT], and peroxidases), and bactericidal activity against Vibrio parahaemolyticus. Expression profiles of penaeidin (PEN), lysozyme (LYZ), and prophenoloxidase (proPO) immune genes were evaluated in hemocytes. In general, an increase in the immune parameters was observed in shrimp fed yeast diet compared to glucan and the control diets. Yarrowia lipolytica, especially strain N6, provided maximum immunostimulatory effects evidenced by the increase of immune parameters (THC, LYZ, SOD, CAT) and gene expression profile. In conclusion, this study demonstrated that Y. lipolytica had immunostimulatory effects and increased bactericidal activity in L. vannamei hemocytes against V. parahaemolyticus. These findings open the path for the potential application of Y. lipolytica-based immunostimulant for shrimp aquaculture.

Preparation of lentinan-calcium carbonate microspheres and their application as vaccine adjuvants.

Adjuvants improve vaccine potency by enhancing immunogenicity and sustaining long-term immune responses. Lentinan (LNT), a ß-1,3-glucohexaose with ß-1,6-branches, is extracted from the mushroom Lentinus edodes and functions as an effective immunostimulatory drug. Previous studies have demonstrated the adjuvant activity of calcium carbonate (CaCO3) microspheres as well as their use as antigen delivery systems. In this study, we successfully loaded CaCO3 microspheres with LNT and evaluated their physicochemical characteristics prior to the adsorption of ovalbumin. Our experimental results demonstrated that LNT-CaCO3 significantly enhanced lymphocyte proliferation, and boosted the frequency of CD69 + B cells and the ratio of CD4+ to CD8 + T cells in spleen lymphocytes. Moreover, LNT-CaCO3 unexpectedly induced the secretion of IgG and Th-associated cytokines (IL-2, IL-4, IFN-γ, and TNF-α) in immunized mice. Therefore, LNT-CaCO3 microspheres induce robust cellular and humoral immune responses and have potential utility as vaccine delivery systems.

Single or Combined Dietary Supply of Psidium guajava and Phyllanthus amarus Extracts Differentially Modulate Immune Responses and Liver Proteome in Striped Catfish (Pangasianodon hyphophthalmus).

Guava Psidium guajava L (Pg) and bhumi amla Phyllanthus amarus Schum. et Thonn (Pa) are well-known plants in traditional medicine. However, the capacity of these plants for improving the immune system of aquatic species has received less attention so far. This study aimed to investigate the effects of single supply or mixture of Pg and Pa extracts on immune responses, disease resistance and liver proteome profiles in striped catfish Pangasianodon hypophthalmus. Fish were fed diets including basal diet 0% or one of three doses of each plant extract, either alone or in mixture, 0.08, 0.2, or 0.5% Pg, Pa or mixture (Pg:Pa, v/v) for 6 weeks. The immune parameters (respiratory burst activity (RBA); nitric oxide synthase (NOS), total immunoglobulin, lysozyme, and complement activities) were examined at W3, W6 post-feeding, and after challenge test. The growth parameters and the challenge test with Edwardsiella ictaluri were done at W6. The liver proteome profiles were analyzed in W6 at 0.08 and 0.5% of each extract. The results showed that extract-based diets significantly improved growth parameters in the Pg0.2 group compared to control. The cellular immune responses in spleen and the humoral immune responses in plasma were significantly improved in a dose and time-dependent manner. Diets supplemented with single Pg and Pa extracts, and to lesser extent to combined extracts, could significantly decrease the mortality of striped catfish following bacterial infection compared to control. The proteomic results indicated that some pathways related to immune responses, antioxidant and lipid metabolism were enriched in liver at W6. Several proteins (i.e., CD8B, HSP90AA1, HSP90AB1, PDIA3, CASP8, TUBA1C, CCKAR, GNAS, GRIN2D, PLCG1, PRKCA, SLC25A5, VDAC2, ACTN4, GNAI2, LCK, CARD9, NLRP12, and NLRP3) were synergistically upregulated in mixture of Pg and Pa-based diets compared to control and single dietary treatments. Taken together, the results revealed that single Pg and Pa extracts at 0.2 and 0.5% and their mixture at 0.08 and 0.5% have the potential to modulate the immune mechanisms and disease resistance of striped catfish. Moreover, the combination of Pg and Pa in diets suggested positive synergistic effects liver proteome profile related to immune system processes.

An SAMT-247 Microbicide Provides Potent Protection against Intravaginal Simian Immunodeficiency Virus Infection of Rhesus Macaques, whereas an Added Vaccine Component Elicits Mixed Outcomes.

Because of microbicide noncompliance and lack of a durable, highly effective vaccine, a combined approach might improve HIV prophylaxis. We tested whether a vaccine-microbicide combination would enhance protection against SIV infection in rhesus macaques. Four macaque groups included vaccine only, vaccine-microbicide, microbicide only, and controls. Vaccine groups were primed twice mucosally with replicating adenovirus type 5 host range mutant SIV env/rev, gag, and nef recombinants and boosted twice i.m. with SIV gp120 proteins in alum. Controls and the microbicide-only group received adenovirus type 5 host range mutant empty vector and alum. The microbicide was SAMT-247, a 2-mercaptobenzamide thioester that targets the viral nucleocapsid protein NCp7, causing zinc ejection and preventing RNA encapsidation. Following vaccination, macaques were challenged intravaginally with repeated weekly low doses of SIVmac251 administered 3 h after application of 0.8% SAMT-247 gel (vaccine-microbicide and microbicide groups) or placebo gel (vaccine-only and control groups). The microbicide-only group exhibited potent protection; 10 of 12 macaques remained uninfected following 15 SIV challenges. The vaccine-only group developed strong mucosal and systemic humoral and cellular immunity but did not exhibit delayed acquisition compared with adjuvant controls. However, the vaccine-microbicide group exhibited significant acquisition delay compared with both control and vaccine-only groups, indicating further exploration of the combination strategy is warranted. Impaired protection in the vaccine-microbicide group compared with the microbicide-only group was not attributed to a vaccine-induced increase in SIV target cells. Possible Ab-dependent enhancement will be further investigated. The potent protection provided by SAMT-247 encourages its movement into human clinical trials.

Nanoformulated Single-Stranded RNA-Based Adjuvant with a Coordinative Amphiphile as an Effective Stabilizer: Inducing Humoral Immune Response by Activation of Antigen-Presenting Cells.

As agonists of TLR7/8, single-stranded RNAs (ssRNAs) are safe and promising adjuvants that do not cause off-target effects or innate immune overactivation. However, low stability prevents them from mounting sufficient immune responses. This study evaluates the adjuvant effects of ssRNA derived from the cricket paralysis virus intergenic region internal ribosome entry site, formulated as nanoparticles with a coordinative amphiphile, containing a zinc/dipicolylamine complex moiety as a coordinative phosphate binder, as a stabilizer for RNA-based adjuvants. The nanoformulated ssRNA adjuvant was resistant to enzymatic degradation in vitro and in vivo, and that with a coordinative amphiphile bearing an oleyl group (CA-O) was approximately 100 nm, promoted effective recognition, and improved activation of antigen-presenting cells, leading to better induction of neutralizing antibodies following single immunization. Hence, CA-O may increase the efficacy of ssRNA-based adjuvants, proving useful to meet the urgent need for vaccines during pathogen outbreaks.

Effect of Jasonia glutinosa on immune and oxidative status of gilthead seabream (Sparus aurata L.).

Jasonia glutinosa (rock-tea, RT) has numerous biological activities. In the present work, the beneficial effects of dietary RT on gilthead seabream (Sparus aurata L.) were studied. Fish fed experimental diets containing 0 (control), 10 or 30% of RT for 15 and 30 days. Samples from skin mucus, blood, head kidney, liver and gut were obtained at 15 and 30 days. The antioxidant properties from RT were analysed such as the antioxidant capacity and phenolic content. The heat shock protein 70 level (HSP70) and the total oxidized proteins were evaluated on skin mucus as stress markers. Immune parameters, both humoral (peroxidase activity, immunoglobulin M levels and complement activity) and cellular (phagocytic, respiratory burst and peroxidase activities) were determined in skin mucus, serum or head-kidney leucocytes, respectively. Concomitantly, the expression of different genes related to inflammation and oxidative stress was studied both in liver and gut. Skin mucus peroxidase was significantly increased on fish fed 10% RT for 15 days with respect to the control group. In addition, Serum IgM levels were significantly increased while HSP70 levels and oxidized proteins were significantly decreased on skin mucus from fish fed 30% RT for 30 days, respectively. Besides, cellular immune parameters (phagocytosis, respiratory burst and peroxidase activity) were significantly higher in leucocytes from fish fed the RT diets for 15 days, but not for 30 days. Finally, the gene expression of antioxidant enzymes was up-regulated in liver at 15 and in liver and gut at 30 days. However, the expression of il1b and hsp70 was down-regulated in the liver of fish fed 30% RT for 30 days with respect to the values of control fish. The possible inclusion of RT in fish diets as an additive with antioxidant and/or immunostimulant activities is discussed.

Effect of an injectable trace mineral supplement on the immune response of dairy calves.

On a spring calving, pastoral dairy farm, the first 40 heifer calves born after calving mid-point (50% of the herd calved) were blood sampled within 24 h. Thirty were selected, using stratified randomisation to form two equal groups (treatment and control) with the same distribution of serum total protein, copper, selenium, zinc, and manganese concentrations, age and breed. From the remaining 10 calves, five were randomly selected into a sentinel group to assess field exposure to Salmonella spp. All calves received two injections of a killed vaccine containing Salmonella spp. antigens at 2 and 6 weeks of age. Concurrently, the treatment group were injected with 1 mL/50 kg trace mineral supplement (TMS) containing 40 mg zinc, 10 mg manganese, 5 mg selenium, 15 mg copper per mL. Sentinel animals received no injections. All animals were bled from 2 to 9 weeks for assay of immune function. At three and four weeks, white blood cells from TMS calves had an increased percentage of cells phagocytosing (effect size = 9.36 and 4.35) and increased number of bacteria ingested per cell (effect size = 0.93 and 1.52). No differences were detected in gamma interferon response (effect size <0.15) or Salmonella sp. antibody titres (effect size <0.20).

Carbohydrate-based adjuvants.

Carbohydrate adjuvants are safe and biocompatible compounds usable as sustained delivery systems and stimulants of ongoing humoral and cellular immune responses, being especially suitable for the development of vaccines against intracellular pathogens where alum is useless. The development of new adjuvants is difficult and expensive, however, in the last two years, seven new carbohydrate-based adjuvants have been patented, also there are twelve ongoing clinical trials of vaccines that contain carbohydrate-based adjuvants, as well as numerous publications on their mechanism of action and safety. More research is necessary to improve the existent adjuvants and develop innovative ones.

Increased vitamin supplement to sows, piglets and finishers and the effect in productivity.

With still limited information on vitamin requirements and considering that many commercial practices adopt dietary vitamin levels above the values suggested by nutritional tables, this study aimed to assess the effect of administering vitamin supplementation to sows in gestation and lactation and to their litters on the reproductive performance and body condition of the sows and on the performance and immune profile of the litters until slaughter. The trial was split into two phases. The first phase used 104 sows, assigned to be randomized to blocks according to parity, submitted until 21 days of lactation to two treatments: control-standard (standard levels of vitamins) and test-elevated (elevated levels of vitamins). Each sow and its respective farrow were considered an experimental unit. The sows underwent evaluations of body condition score, back fat thickness and reproductive performance. In the second phase, 60 barrows and 60 gilts at 21 days of age and mean initial weight of 5.33 ± 1.5 kg until slaughter at 164 days of age. The piglets were assigned to randomized blocks according to the weight and sex of the animals in a 2 × 2 factorial model, with 10 replicates per treatment, where a pen with three animals represented the experimental unit. Following the same treatments of the first phase, the piglets were evaluated for daily weight gain, daily feed intake, feed conversion, mortality rate and humoral immune response. Vitamin supplementation had no positive effects on the reproductive parameters or body composition of sows. However, it positively impacted the performance of the litters in the early nursery stage, but did not lead to superior effects on the immune responses to vaccination against circovirus or mycoplasma.

Effects of Dietary Zinc on Performance, Zinc Transporters Expression, and Immune Response of Aged Laying Hens.

This study was to investigate the effects of dietary zinc (Zn) supplementation on performance, zinc transporter gene expression, and immune function in aged laying hens. In experiment 1, twenty 31-week-old hens (young) and twenty 60-week-old hens (old) with the same genetic background were fed with the same diet for 4 weeks. In experiment 2, a basal diet supplemented with zinc sulfate (ZnS) and zinc glycine chelate (ZnG) at 30, 60, 90, and 120 mg Zn/kg to constitute nine experimental diets. Eight hundred and ten 60-week-old layers were distributed in a completely randomized experimental design with 9 treatments, 6 replicates of 15 birds each, and birds were fed for 10 weeks. In experiment 1, results showed that zinc and metallothionein (MT) concentration in the shell gland of old hens was significantly lower than young layers (P < 0.05). Zinc transporters ZnT1, 4, 5, 6, and 7 messenger RNA (mRNA) abundance in old layers were significantly lower versus the young (P < 0.05). In experiment 2, results indicated that dietary zinc supplementation did not significantly affect the laying rate, average feed intake, egg weight, feed conversion efficiency, broken egg rate, or mortality (P > 0.05). Supplemental ZnG significantly improved eggshell breaking strength than ZnS, with a higher alkaline phosphatase (ALP) activity and more abundant ZnT4 expression in shell gland versus ZnS (P < 0.05). ZnG supplementation at 90 mg Zn/kg affected the duodenal mucus by significantly increasing ZnT1, 6, 7, ZIP13, and MT-4 mRNA level (P < 0.05). Zinc level significantly increased bovine serum albumin (BSA) antibody concentration on 14 day after BSA injection (P < 0.05). Supplementation of ZnG improved eggshell quality of aged layers by upgrading zinc transporter expression in the shell gland and intestine also enhanced humoral immunity.