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Phytoncides in the prevention and therapy of blackhead disease and their effect on the turkey immune system
2021
Tykałowski, Bartłomiej | Śmiałek, Marcin | Kowalczyk, Joanna | Dziewulska, Daria | Stenzel, Tomasz | Koncicki, Andrzej
Turkey histomonosis poses a serious threat to poultry production due to the ban on the use of effective drugs. The aim of the study was to evaluate the influence of a phytoncidal feed supplement on the course of histomonosis. The preparation was also analysed for immunomodulatory properties. Clinical observations and production monitoring were conducted in a flock of turkeys with histomonosis from their 11ᵗʰ to 56ᵗʰ weeks of life which were treated with the adiCoxSᴼᴸPF soluble supplement in a dose of 2.5 mL/L water. Later the preparation was used in a preventive dose (1 mL/L). The influence on the immune system was evaluated in broiler turkeys having been given adiCoxSᴼᴸPF for 3 days in doses of 1 or 3 mL/L. The T and B lymphocyte percentages in turkey blood and spleen tissue were analysed with flow cytometry. ELISA was implemented to evaluate antibody titres after Ornithobacterium rhinotracheale vaccination, and biochemical analyses were performed to evaluate the supplement’s safety. AdiCoxSᴼᴸPF was found effective in therapy and prevention of histomonosis. Additionally, adiCoxSᴼᴸPF stimulated both humoral and cell-mediated immune mechanisms, without impairing the functions of internal organs. The treated turkeys also yielded better production results (eggs/hen, fertility, and hatchability). AdiCoxSᴼᴸPF possesses immunomodulatory properties and it can be used successfully in the prevention and therapy of histomonosis in turkeys.
Afficher plus [+] Moins [-]Estrogen-related receptor α (ERRα) functions in the hypoxic injury of microglial cells
2022
Deng, Chao-Yang | Zhu, Ting-Ting | Lian, Shuai | Wang, Jian-Fa | Wu, Rui | Zheng, Jia-San
Hypoxia is a common pathological condition after spinal cord injury. Oestrogen-related receptor alpha (ERRα), as a key regulator of energy metabolism and mitochondrial functions, plays an important role in maintaining cell homeostasis. However, its role in hypoxic spinal microglia has not been fully elaborated. This study investigated the receptor’s activity when these cells are hypoxic and used as an in vitro model. In this study, microglia (BV2) were exposed to cobalt chloride as a hypoxic model, and the inverse agonist of ERRα, XCT790, and pyrido[1,2-α]-pyrimidin-4-one were used to regulate the expression of the receptor to explore the ERRα-related mechanisms involved in hypoxic spinal cord injury (SCI). ERRα promoted autophagy in BV2 cells and inhibited the activation of the p38 mitogen-activated protein kinase (MAPK) pathway and the expression of anti-inflammatory factors under hypoxic conditions. It also promoted the expression of fibronectin type III domain containing protein 5 (FNDC5). When a hypoxic SCI occurs, ERRα may maintain the homeostasis of spinal cord nerve cells by regulating autophagy and the p38MAPK/nuclear factor-kappa B cell and FNDC5/brain-derived neurotrophic factor signalling pathways, which are beneficial to the recovery of these cells.
Afficher plus [+] Moins [-]Immune-enhancing activity of potential probiotic strains of Lactobacillus plantarum in the common carp (Cyprinus carpio) fingerling
2018
Kazuń, Barbara | Małaczewska, Joanna | Kazuń, Krzysztof | Żylińska-Urban, Joanna | Siwicki, Andrzej K.
Introduction: Immune-potentiating functions of Lactobacillus plantarum strains in the common carp were evaluated. Material and Methods: Fourteen days of feeding fish dry diet supplemented with the bacteria provided parameters of nonspecific humoral immunity (lysozyme, ceruloplasmin, γ-globulin, total protein levels, and serum bactericidal activity) and cellular immunity (pinocytosis, respiratory burst activity, and potential killing activity of organ phagocytes), as well as the proliferative response of organ lymphocytes stimulated with mitogens. The resistance of fish to infection with Aeromonas hydrophila was also determined. Results: Dietary supplementation with L. plantarum had a substantial influence on the activity of organ phagocytes, especially the potential killing activity of head kidney cells. A significant increase in the proliferative activity of LPS-stimulated B lymphocytes and in the levels of γ-globulins and total protein was observed. The supplemented diet conveyed higher resistance than the control diet as the cumulative fish mortalities after infection with A. hydrophila were 65% and 85%, respectively. Conclusion: The results indicate that dietary supplementation with L. plantarum stimulates the antibacterial resistance of common carp and may reinforce defence against bacterial infections, but further studies need to be conducted.
Afficher plus [+] Moins [-]Immunopathologic study and characterization of the phenotype of transformed cells in sheep with bovine leukemia virus-induced lymphosarcoma
1994
Murakami, K. | Aida, Y. | Kageyama, R. | Numakunai, S. | Ohshima, K. | Okada, K. | Ikawa, Y.
We used monoclonal antibodies and immunohistologic examination of lymph nodes, to elucidate the pathogenesis of lymphosarcoma induced by, infection with bovine leukemia virus (BLV). The superficial cervical lymph nodes from 3 BLV-infected but apparently healthy sheep and 5 sheep with full-blown lymphosarcoma were examined. We also investigated the integration of bovine leukemia provirus by use of Southern blotting. In lymph nodes from sheep lacking clinical signs of infection, in which the provirus had been integrated at multiple sites in the genome, many large hypertrophic follicles were observed in the cortex. These follicles had germinal centers consisting of CD4+T cells and B cells that expressed surface IgM (sIgM) and major histocompatibility complex (MHC) class-II antigens, but not B cell-specific B2 molecule. The percentage of CD4+T cells in the cortex was significantly (P < 0.05) higher than that of the controls and sheep with lymphosarcoma. In all sheep with lymphosarcoma, the lymph nodes were completely destroyed by proliferating neoplastic cells, and in addition, small atrophic follicles, which consisted of normal B-cell marker-positive cells, were seen near the trabecula and the subcapsule. In these instances, neoplastic cells appeared to be a monoclonal population derived from a single CD5- B-cell lineage and to be classified as 2 types, CD5-CD4-CD8-B2+MHC class-II+sIgM+ and CD5-CD4-CD8-B2+MHC class-II+sIgM-. Moreover, CD8+T cells infiltrated diffusely throughout the tumorous lymph nodes apart from the atrophic follicles, and CD4+T cells were observed around atrophic follicles. Both types of T cells were small-size, normal lymphocytes with round and noncleaved nuclei, and were apparently non-neoplastic cells. In fact, after separation by use of a panning method, it seems that, in blood mononuclear cells from BLV-infected sheep without clinical signs of infection, but in lymphosarcomatous stages, the proviral genome was integrated only in B cells and not in T cells. Thus, we conclude that the host's immune response may be still maintained at a lymphosarcomatous stage.
Afficher plus [+] Moins [-]Further phenotypic characterization of target cells for bovine leukemia virus experimental infection in sheep
1989
Aida, Y. | Miyasaka, M. | Okada, K. | Onuma, M. | Kogure, S. | Suzuki, M. | Minoprio, P. | Levy, D. | Ikawa, Y.
To determine the phenotype of target cells for bovine leukemia virus (BLV) infection in sheep, we analyzed blood lymphocytes from BLV-infected clinically healthy and leukemic sheep by used of monoclonal antibodies. In clinically healthy and leukemic sheep that were BLV-infected, the blood concentration of T lymphocytes was within normal values, but the number of B lymphocytes was increased in several cases. In addition, the number of blood lymphocytes expressing the BLV antigen correlated well with that of B lymphocytes. Double immunofluorescence staining demonstrated that lymphocytes expressing BLV antigens bore B-cell but not T-cell surface markers. Moreover, neoplastic cells in the lymph nodes of leukemic sheep were stained immunohistochemically with an anti-B monoclonal antibody but not with any of anti-T monoclonal antibody tested, indicating that tumor cells are of B-lymphocyte origin. Collectively, these results show that BLV antigen-positive cells obtained from BLV-infected sheep that have no clinical signs and BLV-induced lymphosarcoma cells belong to the B-lymphocyte lineage.
Afficher plus [+] Moins [-]Enumeration of T and B lymphocytes in bovine leukemia virus-infected cattle, using monoclonal antibodies
1988
Williams, D.L. | Amborski, G.F. | Davis, W.C.
Monoclonal antibodies and microfluorimetry were used to determine the absolute number of B and T lymphocytes in the blood of bovine leukemia virus (BLV)-infected cows. The blood lymphocyte populations from BLV-infected cows were significantly higher than those from BLV-negative cows. The increase in the lymphocyte population in 3 BLV-infected nonlymphocytotic cows was attributed to a significant increase in the number of T lymphocytes; in 3 BLV-infected persistently lymphocytotic cows, the increase was attributed to a significant increase in the number of B and T lymphocytes. One persistently lymphocytotic cow had a high lymphocyte count, and lymphocytes from this cow contained cells that appeared to stain with markers specific for bovine B and T lymphocytes. We concluded that infection of cattle with the B-cell lymphotropic retrovirus, BLV, not only affected B cells, but also T cells.
Afficher plus [+] Moins [-]Luteinizing hormone receptor expression by nonneoplastic and neoplastic canine lymphocytes
2019
Ettinger, Alyssa M. | Gust, Sabrina K. | Kutzler, Michelle A.
OBJECTIVE To investigate luteinizing hormone (LH) receptor expression in canine nonneoplastic and neoplastic lymph nodes, circulating nonneoplastic lymphocytes, and T-cell lymphoma (TCL) cell lines. SAMPLE Formalin-fixed, paraffin-embedded lymph nodes (5 neoplastic and 3 nonneoplastic) from 6 dogs, circulating lymphocytes from venous blood specimens obtained from 12 healthy dogs, and 3 TCL cell lines derived from 3 dogs with primary lymphoma. PROCEDURES Lymph node specimens were immunohistochemically stained for determination of LH receptor expression. Circulating nonneoplastic lymphocytes and TCL cell lines were evaluated for LH receptor expression by use of flow cytometry; circulating lymphocytes were also immunophenotyped. The mean percentage of cells positive for LH receptors was determined for each type of specimen. For the healthy dogs, percentages of circulating B and T lymphocytes that expressed LH receptors were assessed on the basis of sex and reproductive status. RESULTS The mean percentage of LH receptor-positive cells in canine neoplastic and nonneoplastic lymph nodes was 12.4% and 4.1%, respectively. For the healthy dogs, the mean percentage of circulating LH receptor-positive T lymphocytes was significantly higher in gonadectomized dogs (16.6%) than in sexually intact dogs (10.5%); the percentages of circulating LH receptor-positive B lymphocytes did not significantly differ by reproductive status. Among the 3 canine TCL cell lines, LH receptor expression ranged from 10% to 45%. CONCLUSIONS AND CLINICAL RELEVANCE In this study, LH receptor expression by canine neoplastic and nonneoplastic lymphocytes was detected. Research into the effects of downregulation of LH receptor activation in dogs with lymphoma is warranted.
Afficher plus [+] Moins [-]Changes in leukocyte populations of cows with milk fever or displaced abomasum after calving
2013
Ohtsuka, Hiromichi | Fukuda, Shigeo | Kudo, Katsunori | Tomioka, Michiko | Koiwa, Masateru | Kimura, Kayoko
Most of the metabolic diseases of dairy cows occur within the first 2 wk after calving, and cows with a metabolic disease are prone to infectious diseases. Although metabolic diseases are generally recognized as a risk factor for infectious diseases owing to the associated decrease in immune function, the difference in immune status between cows with milk fever (MF) or displaced abomasum (DA) during the lactation period has not been clarified. Therefore, the peripheral blood leukocyte populations in 38 multiparous Holstein cows from 1 herd were analyzed after calving. The cows were divided into 3 groups according to health: 21 cows that remained clinically healthy throughout the experimental period (control group), 9 cows that had MF on the day of calving, and 8 cows with an onset of DA within 4 wk after calving. The T- and B-cell numbers were lowest at week 0, and they increased gradually after calving. There was no significant difference between the 3 groups in the number of each subset of leukocytes on the day of calving, but the number of CD8+ T-cells was significantly lower in the MF and DA groups than in the control group at week 1. The numbers of CD4+, CD8+, and WC1+ T-cells tended to be lower in the DA group than in control group from weeks 4 to 12, a tendency not observed in the MF group. These data suggest that when cows have DA around the time of calving, their lymphocyte numbers remain lower until 12 wk after calving.
Afficher plus [+] Moins [-]Immunohistochemical and immunopathologic characterization of superficial stromal immune-mediated keratitis in horses
2012
Pate, Diana O. | Clode, Alison B. | Olivry, Thierry | Cullen, J. M. (John M) | Salmon, Jacklyn H. | Gilger, Brian C.
Objective: To describe the immunopathologic characteristics of superficial stromal immune-mediated keratitis (IMMK) immunopathologically by characterizing cellular infiltrate in affected corneas of horses. Animals: 10 client-owned horses with IMMK. Procedures: Immunohistochemical staining was performed on keratectomy samples with equine antibodies against the T-cell marker CD3 and B-cell marker CD79a (10 eyes) and the T-helper cytotoxic marker CD4 and T-cell cytotoxic marker CD8 (6 eyes). Percentage of positively stained cells was scored on a scale from 0 (no cells stained) to 4 (> 75% of cells stained). Equine IgG, IgM, and IgA antibodies were used to detect corneal immunoglobulin via direct immunofluorescence (10 eyes). Serum and aqueous humor (AH) samples from 3 horses with IMMK were used to detect circulating and intraocular IgG against corneal antigens via indirect immunofluorescence on unaffected equine cornea. Results: Percentage scores (scale, 0 to 4) of cells expressing CD3 (median, 2.35 [range, 0.2 to 3.7]; mean ± SD, 2.36 ± 1.08) were significantly greater than scores of cells expressing CD79a (median, 0.55 [range, 0 to 1.5]; mean, 0.69 ± 0.72). All samples stained positively for CD4- and CD8-expressing cells, with no significant difference in scoring. All samples stained positively for IgG, IgM, and IgA. No serum or AH samples collected from horses with IMMK reacted with unaffected equine cornea. Conclusions and Clinical Relevance: Pathogenesis of superficial stromal IMMK included cell-mediated inflammation governed by both cytotoxic and helper T cells. Local immunoglobulins were present in affected corneas; however, corneal-binding immunoglobulins were not detected in the serum or AH from horses with IMMK.
Afficher plus [+] Moins [-]Flow cytometric evaluation of peripheral blood and bone marrow and fine-needle aspirate samples from multiple sites in dogs with multicentric lymphoma
2012
Joetzke, Alexa E. | Eberle, Nina | Nolte, Ingo | Mischke, Reinhard | Simon, Daniela
Objective: To determine whether the extent of disease in dogs with lymphoma can be assessed via flow cytometry and to evaluate the suitability of fine-needle aspirates from the liver and spleen of dogs for flow cytometric examination. Animals: 44 dogs with multicentric B-cell (n = 35) or T-cell lymphoma (9) and 5 healthy control dogs. Procedures: Peripheral blood and bone marrow samples and fine-needle aspirates of lymph node, liver, and spleen were examined via flow cytometry. Logarithmically transformed T-cell–to–B-cell percentage ratio (log[T:B]) values were calculated. Thresholds defined by use of log(T:B) values of samples from control dogs were used to determine extranodal lymphoma involvement in lymphoma-affected dogs; results were compared with cytologic findings. Results: 12 of 245 (5%) samples (9 liver, 1 spleen, and 2 bone marrow) had insufficient cellularity for flow cytometric evaluation. Mean log(T:B) values of samples from dogs with B-cell lymphoma were significantly lower than those of samples from the same site in dogs with T-cell lymphoma and in control dogs. In dogs with T-cell lymphoma, the log(T:B) of lymph node, bone marrow, and spleen samples was significantly higher than in control dogs. Of 165 samples assessed for extranodal lymphoma involvement, 116 (70%) tested positive via flow cytometric analysis; results agreed with cytologic findings in 133 of 161 (83%) samples evaluated via both methods. Conclusions and Clinical Relevance: Results suggested that flow cytometry may aid in detection of extranodal lymphoma involvement in dogs, but further research is needed. Most fine-needle aspirates of liver and spleen were suitable for flow cytometric evaluation.
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