Zbigniew Grądzki

The effect of feed supplementation with zinc chelate and zinc sulphate on selected humoral and cell-mediated immune parameters and cytokine concentration in broiler chickens.

The ability of poultry to withstand infectious disease caused by bacteria, viruses or protozoa depends upon the integrity of the immune system. Zinc is important for proper functioning of heterophils, mononuclear phagocytes and T lymphocytes. Numerous data indicate that the demand for zinc in poultry is not met in Poland due to its low content in feeds of vegetable origin. The aim of the study was to determine the effect of supplementation of inorganic (ZnSO4 and ZnSO4+ phytase enzyme), and organic forms of zinc (Zn with glycine and Zn with glycine and phytase enzyme) on selected parameters of the cellular and humoral immune response in broiler chickens by evaluating the percentage of CD3+CD4+, CD3+CD8+, CD25+, MHC Class II, and BU-1+ lymphocytes, the phagocytic activity of monocytes and heterophils, and the concentration of IL-2, IL-10 and TNF-α in the peripheral blood. Flow cytometry was used to determine selected cell-mediated immune response parameters. Phagocytic activity in whole blood was performed using the commercial Phagotest kit (ORPEGEN-Pharma, Immuniq, Poland). The results showed that supplementation with zinc chelates causes activation of the cellular and humoral immune response in poultry, helping to maintain the balance between the Th1 and Th2 response and enhancing resistance to infections. In contrast with chelates, the use of zinc in the form of sulphates has no immunomodulatory effect and may contribute to the development of local inflammatory processes in the digestive tract, increasing susceptibility to infection.

Effects of feed supplementation with glycine chelate and iron sulfate on selected parameters of cell-mediated immune response in broiler chickens

Because little is known about the impact of chelated (Fe-Gly, Fe-Gly+F) and inorganic (FeSO4, FeSO4+F) iron products on immune response parameters in broiler chickens, the objective of the study was to determine the effects of inorganic and organic forms of iron on selected parameters of the cell-mediated immune response in broiler chickens by assessing the percentage of CD3(+)CD4(+), CD3(+)CD8(+), CD25(+), and MHC Class II lymphocytes, as well as the CD4(+)/CD8(+) ratio and IL-2 concentration in the peripheral blood. The experiments were conducted using 50day-old Ross 308 roosters. The test material was peripheral blood. Flow cytometry was used to determine selected cell-mediated immune response parameters. The results obtained indicate that the use of iron chelates in the diet of broiler chickens may stimulate cellular defense mechanisms. As a result of the experiment an increase was observed in the percentage of Th1, mainly T CD4(+) and T CD8(+). It was also noted that application of chelated iron can increase production of T CD8(+) cytotoxic cells and IL-2, which promotes the bodys natural response to developing inflammation. There were no changes in T CD4(+), T CD8(+), T CD25(+) or MHC II lymphocyte subpopulations in the chickens following application of the inorganic form of iron.

Phase I/II Clinical Trial of Encapsulated, Cytochrome P450 Expressing Cells as Local Activators of Cyclophosphamide to Treat Spontaneous Canine Tumours

Based upon promising preclinical studies, a clinical trial was performed in which encapsulated cells overexpressing cytochrome P450 enzyme isoform 2B1 were implanted around malignant mammary tumours arising spontaneously in dogs. The dogs were then given cyclophosphamide, one of the standard chemotherapeutic agents used for the treatment of mammary tumours. The dogs were assessed for a number of clinical parameters as well as for reduction in tumour size. The treatment was well tolerated with no evidence of adverse reactions or side effects being associated with the administration of the encapsulated cells. Reductions in tumour size of more than 50% were observed for 6 out of the 11 tumours analysed while 5 tumours showing minor responses, i.e. stable disease. In contrast, the tumours that received cyclophosphamide alone showed only stable disease. Taken together, this data suggests that encapsulated cytochrome P450 expressing cells combined with chemotherapy may be useful in the local treatment of a number of dog mammary tumours and support the performance of further clinical studies to evaluate this new treatment.

Effect of feed supplementation with zinc glycine chelate and zinc sulfate on cytokine and immunoglobulin gene expression profiles in chicken intestinal tissue

&NA; The aim of the study was to evaluate the effect of inorganic and organic forms of Zn on the expression of cytokines (IL‐2, TNF‐&agr;, IFN‐&ggr;, IL‐12, IL‐17, IL‐4, IL‐10, and TGF‐&bgr;) and immunoglobulins (IgA and IgG) in the tissues of the small intestine (jejunum and ileum) of broiler chickens. In the experiment, 90 broiler chickens were divided into 4 experimental groups and a control group, with 18 birds each. The birds received Zn supplements in inorganic form with and without phytase (ZnSO4 and ZnSO4 + F), and in organic form with glycine, with and without phytase (Zn‐Gly and Zn‐Gly + F). The total rearing period was 42 days. Quantitative real‐time (RT)‐PCR was used to measure the expression of the cytokines and immunoglobulins. The differences between the results obtained for the control and experimental groups, between the groups receiving ZnSO4 and Zn‐Gly, and between groups ZnSO4‐F and Zn‐Gly‐F were analyzed statistically. High relative expression of IL‐2 was observed for the chickens in the groups receiving ZnSO4‐F, Zn‐Gly, and Zn‐Gly‐F on d 42 in comparison to the control group. High relative expression of TNF‐&agr;, IL‐12, and IL‐17 was noted in the group that received ZnSO4 + F. High expression of IgG, IgA, IL‐4, TGF‐&bgr;, and IL‐10 was noted in the groups of chickens that received feed supplemented with Zn‐Gly and Zn‐Gly + F chelates on d 42 of the study in comparison to the control group. In conclusion, supplementation with Zn‐Gly chelates can ensure Th1 and Th2 balance during the immune response in the gut‐associated lymphoid tissue (GALT), and, by increasing IgA and IgG expression, also can stimulate potentiation of the immune response involved in passive protection of the body from infection. In contrast, the use of inorganic forms of Zn, in the form of sulfates, can induce local inflammatory processes in the intestines, which, in the case of long‐term supplementation, lead to the development of infections.

The effect of feed supplementation with effective microorganisms (EM) on pro- and anti-inflammatory cytokine concentrations in pigs

Effective microorganisms (EM) are used in numerous fields associated with agriculture. The beneficial effects of EM on the general health of pigs and on production parameters are also determined by the influence of these microbes on immunity. The aim of the study was to assess the effect of feed supplementation with EM on the concentration of pro- and anti-inflammatory cytokines in the serum and in a culture of PBMCs with and without ConA stimulation in pigs. ELISA kits were used to determine the cytokine levels in the porcine serum and the PBMC culture supernatants. Evaluation of the serum concentration of cytokines revealed statistically significantly higher concentrations of IL-2, IL-4, IL-10, IFN-γ and TNF-α in the pigs receiving EM Bokashi. The highest concentration of TGF-β in the experimental group was noted on the final test day. Evaluation of cytokine concentrations in the PBMC cultures revealed statistically significantly higher concentrations of IL-2, IL-4 and IL-10 from the third day of the experiment. Statistically significantly higher concentrations of TNF-α were obtained in the unstimulated PBMC culture on the second test day and in the culture treated with ConA on the second and the third test days. The results of our study indicate that supplementation of pig feed with EM Bokashi activates the cell-mediated and humoral immune response, ensuring that Th1/Th2 balance is maintained and enhancing immune processes protecting the body against infection.

The effect of feed supplementation with Zakarpacki zeolite (clinoptilolite) on percentages of T and B lymphocytes and cytokine concentrations in poultry

&NA; The available literature lacks information on the effect of Zakarpacki zeolite (clinoptilolite) on the immune system of poultry. Therefore, the aim of this study was to determine the effect of this zeolite on selected indicators of the immune response in poultry by evaluating the expression of cluster of differentiation (CD) surface molecules on T and B lymphocytes and the concentration of IL‐2 and IL‐10 in the blood. Ninety one‐day‐old Ross 308 broiler chicks were used in the study. The birds were divided into 3 groups of 30 each. The same basic diet was used in all groups, but groups II and III received a feed additive in the form of 2% and 3% zeolite. Blood samples were collected from all birds on the 40th day of observations. Weight gain in the birds in both experimental groups was significantly higher, and no clinical symptoms of disease were observed. The percentage of CD4+CD25+ T and B lymphocytes was higher in both groups receiving zeolite, but the percentage of CD8+CD25+ T lymphocytes was higher only in the group receiving 3% zeolite. There were no differences between the groups in the percentage of cells with CD3+ and MHC Class II expression. Higher serum concentrations of IL‐2 and IL‐10 were noted only in group III. The use of zeolites enhances antigen presentation and leads to increased Th1 and Th2 response. Excessive supply of zeolite in the feed leads to a local inflammatory response, which may cause damage to the intestinal barrier.

Plasmid Profiles of Virulent Rhodococcus equi Strains Isolated from Infected Foals in Poland

Rhodococcus equi is an important bacterial pathogen in foals up to 6 months old, widespread in horse farms all over the world. It was found that only virulent R. equi strains expressing 15–17 kDa virulence-associated protein (VapA) and having large virulence plasmid of 85–90 kb containing vapA gene are pathogenic for horses. To date, 12 plasmid types have been reported in VapA positive strains from horses. There are no data concerning plasmid types of Polish field R. equi strains isolated from horses and horse farm environment. The aim of the study is to determine plasmid profiles of virulent R. equi strains isolated in Poland from dead foals as well as from soil samples taken from horse breeding farms. Plasmid profiles of 10 clinical strains derived from 8 farms and 11 environmental strains from 3 farms, confirmed as virulent by PCR, were compared with 12 reference strains containing the known plasmid size and type. Plasmid DNAs were analysed by digestion with the restriction endonucleases BamHI, EcoRI, EcoT22I, and HindIII for detailed comparison and estimation of plasmid sizes. The results of RFLP analysis revealed that all except one isolates used in the study are classified as VapA 85 kb type I plasmid. One strain harboured VapA 87 kb type I plasmid. This is the first report of plasmid types of Polish field R. equi strains. The results of our preliminary investigations on horse farms located in central and eastern Poland indicate that the virulent R. equi strains thus far isolated from diseased foals and horse farms environment represent a highly uniform plasmid pattern.

Effect of the EM Bokashi® Multimicrobial Probiotic Preparation on the Non-specific Immune Response in Pigs

The aim of the study was to determine the effect of EM Bokashi® on the phagocytic activity of monocytes and granulocytes, oxidative burst, SWC3, and CD11b + CD18+ expression on monocytes and granulocytes, and the serum concentration of cytokine and lysozyme in pig. 60 Sixty female piglets were divided into two groups: I – control and II – experimental. For the experimental group, a probiotic in the form of the preparation EM Bokashi® was added to the basal feed. Flow cytometry was used to determine selected non-specific immune response parameters, intracellular production of hydrogen peroxide by peripheral granulocytes and monocytes, and surface particles in peripheral blood. The EM Bokashi® preparation used in the study was found to increase phagocytic activity mainly in monocytes, with an increased percentage of phagocytic cells in the experimental group. The highest serum lysozyme concentration in the piglets in the experimental group (2.89 mg/dl), was noted on day 42 of the study. In the group of pigs receiving EM Bokashi®, the percentage of phagocytic cells with SWC3 (monocyte/granulocyte) expression was statistically significantly higher than in the control. The increase in the number of cells with SWC3 (monocyte/granulocyte) expression in the peripheral circulation in combination with the greater capacity of the cells for phagocytosis and respiratory burst confirms that the non-specific immune response was modulated in the pigs supplemented with EM Bokashi®.

Molecular analysis of the chromosomal 16S rRNA gene and vapA plasmid gene of Polish field strains of R. equi

Rhodococcus equi (R. hoagii) is an opportunistic pathogen commonly found in foals up to 6 months old and animal environment. The R. equi genome contains genetically stable chromosomal DNA and an 80–90 kb plasmid containing vapA gene, responsible for virulence. Most reports from around the world focus on the determination of R. equi plasmid profiles. Few studies have attempted to determine differences in nucleotide sequences between virulent strains of R. equi isolated from foals and breeding environment. The aim of the study was to perform a molecular analysis of a fragment of the chromosomal gene encoding the 16S rRNA subunit and the vapA plasmid gene of virulent R. equi strains isolated on Polish studs from foals and from the breeding environment of horses. The sequencing method was used to compare the primary structure of fragments of the chromosomal and plasmid DNA of the virulent R. equi strains. The sequences of 22 clinical and 18 environmental R. equi isolates were compared with the sequences of the gene fragments of reference strains available in the NCBI GenBank database. All sequenced 16S rRNA amplicons of Polish field strains were identical and showed 99.5% similarity to the four randomly selected sequences of this gene fragment in the GenBank database. The results confirm that fragments of the 16S rRNA gene of R. equi strains are highly conserved and do not undergo variation in field conditions. Analysis of the sequencing results for the vapA gene fragment of the strains used in our study revealed two polymorphic variants and clear differences between the sequences of strains isolated from foals and from soil samples. Presumably, R. equi strains present in the breeding environment are more exposed than clinical strains to adverse external factors. This may result in changes in the DNA sequence due to natural selection.