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Effect of infectious bursal disease virus on response of turkeys to infection by avian influenza virus (H9N2) Texto completo
2017
Hashemzade, Farhad | Mayahi, Mansouir | Shoshtary, Abdol Hamid | Seyfi Abad Shapouri, Masoud Reza | Gourbanpoor, Masoud
BACKGROUND: Infection by infectious bursal disease virus (IBDV) in turkeys may lead to immunosuppression effects and therefore turkeys could not resist against pathogenic or less pathogenic agents. OBJECTIVE: The aim of present study was to examine the effects of IBDV on response of turkey’s poults to avian influenza virus (AIV).METHODS: A total of 100 day-old poults were divided randomly into 4 equal groups. Groups 1 and 2 were infected with 104CID50 of IBDV by oral route at 1 day of age; groups 1 and 3 were infected with 106 EID50 of AIV (H9N2) by the oculo-nasal route at day 30. Poults of group 4 were kept as uninfected control group. All groups were vaccinated with Newcastle disease virus (NDV) vaccine. Blood samples via wing web were collected at days 0, 30, 37, 44, 51 and 58 and anti- NDV and anti-AIV serum titers were measured by HI test. At days 33 and 41 three poults of each group were euthanized and their splenic lymphocytes proliferation repose to phytohaemagglutinin was assessed. RESULTS: Influenza clinical signs were prolonged and more intensive in group 1 than group 3. The mean HI titers to NDV were significantly lower in group 1 than group 3, in all sampling times, but anti-AIV titers were significantly lower in group 1 compared to group 3 from days 14 AIV (H9N2) post infection. The lymphocyte proliferation assay with PHA did not show any differences between groups 1 and 3. CONCLUSIONS: IBDV suppresses immune response in turkey and causes prolonged and more intensive clinical signs after challenge with AIV.
Mostrar más [+] Menos [-]Microorganisms isolated from the corneal surface before and during topical cyclosporine treatment in dogs with keratoconjunctivitis sicca.
1995
Salisbury M.A.R. | Kaswan R.L. | Brown J.
The effect that topical administration of cyclosporine would have on the number and type of microorganisms isolated from the corneal surface of dogs with keratoconjunctivitis sicca was studied. Schirmer tear tests were performed on and corneal swab specimens were collected from 61 eyes of 31 dogs with keratoconjunctivitis sicca prior to and after 3, 6, and 12 months of treatment with cyclosporine. In eyes that responded to cyclosporine treatment (Schirmer tear test value increased by greater than or equal to 5 mm/min, compared with pretreatment value), the percentage of eyes from which bacteria were isolated after 3, 6, and 12 months of treatment was significantly (P < 0.001) less than the percentage from which bacteria were isolated prior to treatment. However, among eyes that did not respond to treatment, we did not detect a significant change over time in prevalence of bacteria or type of bacteria isolated. The percentage of eyes from which fungi were isolated decreased during treatment; however, the small number of eyes in which fungal culture results were initially positive precluded demonstration of a significant change. For all eyes, we did not detect any significant differences over time in the frequency with which specific bacterial genera were isolated, with the exception of beta-hemolytic Streptococcus spp. Opportunistic corneal infections were not detected even though none of the dogs received antibiotics. An increase in production of tears, which contain anti-infection proteins, was believed to be the primary factor responsible for the decrease in the percentage of eyes from which microorganisms could be isolated.
Mostrar más [+] Menos [-]Effects of alpha-ketoisocaproate on adrenocorticotropin-induced suppression of lymphocyte function in sheep.
1991
Kuhlman G. | Roth J.A. | Nissen S.
Previous studies of the amino acid analogue, alpha-ketoisocaproate (KIC), indicate that it can stimulate lymphocyte blastogenesis and antibody responses of sheep. To determine whether KIC could overcome the effects of adreno-corticotropic hormone (ACTH)-induced lymphocyte suppression, 24 lambs were fed a control diet, a diet supplemented with 0.05% KIC, or a diet supplemented with 0.05% of the parent amino acid leucine. Immune status was monitored by determining lymphocyte blastogenic responsiveness to phytohemagglutinin-P (PHA), concanavalin A (conA), and pokeweed mitogen (PWM) and percentages of T-cell subsets in the blood, using monoclonal antibodies and a flow cytometer. Serum cortisol, insulin, and glucagon concentrations also were determined. After 60 days of consuming the respective diet, lambs were administered either saline solution or ACTH (100 IU) twice daily for 3 consecutive days. Administration of ACTH increased serum cortisol and insulin concentrations; however, no effects were seen for serum glucagon concentration. Compared with saline administration, ACTH administration significantly (P < 0.05) suppressed mitogen-stimulated lymphocyte blastogenesis by approximately 50%, regardless of the mitogen used, and significantly (P < 0.01) decreased the percentage of circulating T lymphocytes and decreased (P < 0.01) the ratio of T4 to T8 cells. Lambs fed KIC had greater PHA- and conA-stimulated blastogenic responses and significantly (P < 0.05) increased ratio of T4 to T8 cells in the blood, compared with lambs fed the leucine-supplemented diet or the control diet and given corresponding injections. These data indicate that ACTH decreased in vitro lymphocyte blastogenesis and altered the subset ratios of blood lymphocytes in sheep. These changes were partially prevented by feeding KIC.
Mostrar más [+] Menos [-]Avian reticuloendotheliosis in chickens – an update on disease occurrence and clinical course Texto completo
2018
Woźniakowski, Grzegorz | Frant, Maciej | Mamczur, Andrzej
Avian reticuloendotheliosis in chickens – an update on disease occurrence and clinical course Texto completo
2018
Woźniakowski, Grzegorz | Frant, Maciej | Mamczur, Andrzej
Avian reticuloendotheliosis (RE) represents an important immunosuppressive disease of poultry. The occurrence of RE in both chickens and turkeys has an immunosuppressive effect and may lead to vaccination failures. Avian reticuloendotheliosis virus (REV) is widely distributed in different kinds of birds, causing subclinical infections. Another important issue adhering to this disease is contamination of vaccines against fowl pox (FP) and Marek’s disease (MD) with REV. The capability of REV to integrate into the genome of other larger DNA viruses complicates its diagnosis and prevention. There are no efficient vaccines against RE nor treatment, which also complicates how to limit its impact on poultry farming. This paper reviews the current state of knowledge of this important immunosuppressive agent of poultry emphasising the importance of this problem in terms of diagnosis of RE.
Mostrar más [+] Menos [-]Avian reticuloendotheliosis in chickens – an update on disease occurrence and clinical course Texto completo
2018
Woźniakowski Grzegorz | Frant Maciej | Mamczur Andrzej
Avian reticuloendotheliosis (RE) represents an important immunosuppressive disease of poultry. The occurrence of RE in both chickens and turkeys has an immunosuppressive effect and may lead to vaccination failures. Avian reticuloendotheliosis virus (REV) is widely distributed in different kinds of birds, causing subclinical infections. Another important issue adhering to this disease is contamination of vaccines against fowl pox (FP) and Marek’s disease (MD) with REV. The capability of REV to integrate into the genome of other larger DNA viruses complicates its diagnosis and prevention. There are no efficient vaccines against RE nor treatment, which also complicates how to limit its impact on poultry farming. This paper reviews the current state of knowledge of this important immunosuppressive agent of poultry emphasising the importance of this problem in terms of diagnosis of RE.
Mostrar más [+] Menos [-]Mechanisms of tumour escape from immune surveillance Texto completo
2016
Lisiecka, Urszula | Kostro, Krzysztof
Mechanisms of tumour escape from immune surveillance Texto completo
2016
Lisiecka, Urszula | Kostro, Krzysztof
The progressive growth and spread of tumour cells in the form of metastases requires an interaction of healthy host cells, such as endothelial cells, fibroblasts, and other cells of mesenchymal origin with immune cells taking part in innate and adaptive responses within the tumour lesion and entire body. The host cells interact with tumour cells to create a dynamic tumour microenvironment, in which healthy cells can both positively and negatively influence the growth and spread of the tumour. The balance of cellular homeostasis and the effect of substances they secrete on the tumour microenvironment determine whether the tumour has a tendency to grow or disappear, and whether the cells remain within the lesion or are capable of metastasis to other regions of the body. Intercellular interactions also determine the tumour’s susceptibility to radiation or other types of cancer treatment. They may also be a rational explanation for differences in treatment outcomes, in which some metastases regress and others progress in response to the same treatment method.
Mostrar más [+] Menos [-]Mechanisms of tumour escape from immune surveillance Texto completo
2016
Lisiecka Urszula | Kostro Krzysztof
The progressive growth and spread of tumour cells in the form of metastases requires an interaction of healthy host cells, such as endothelial cells, fibroblasts, and other cells of mesenchymal origin with immune cells taking part in innate and adaptive responses within the tumour lesion and entire body. The host cells interact with tumour cells to create a dynamic tumour microenvironment, in which healthy cells can both positively and negatively influence the growth and spread of the tumour. The balance of cellular homeostasis and the effect of substances they secrete on the tumour microenvironment determine whether the tumour has a tendency to grow or disappear, and whether the cells remain within the lesion or are capable of metastasis to other regions of the body. Intercellular interactions also determine the tumour’s susceptibility to radiation or other types of cancer treatment. They may also be a rational explanation for differences in treatment outcomes, in which some metastases regress and others progress in response to the same treatment method.
Mostrar más [+] Menos [-]Characterisation of fowl adenovirus (FAdV-8b) strain concerning the geographic analysis and pathological lesions associated with inclusion body hepatitis in broiler flocks in Turkey Texto completo
2020
Cizmecigil, Utku Yusuf | Umar, Sajid | Yilmaz, Aysun | Bayraktar, Erhan | Turan, Nuri | Tali, Besim | Aydin, Ozge | Tali, Hasan Emre | Yaramanoglu, Mehmetcan | Yilmaz, Semaha Gul | Kolukisa, Ahmet | Sadeyen, Jean-Remy | Munir, Iqbal | Yılmaz, Hüseyin
Characterisation of fowl adenovirus (FAdV-8b) strain concerning the geographic analysis and pathological lesions associated with inclusion body hepatitis in broiler flocks in Turkey Texto completo
2020
Cizmecigil, Utku Yusuf | Umar, Sajid | Yilmaz, Aysun | Bayraktar, Erhan | Turan, Nuri | Tali, Besim | Aydin, Ozge | Tali, Hasan Emre | Yaramanoglu, Mehmetcan | Yilmaz, Semaha Gul | Kolukisa, Ahmet | Sadeyen, Jean-Remy | Munir, Iqbal | Yılmaz, Hüseyin
Fowl adenovirus can cause important diseases in chickens such as inclusion body hepatitis, hepatitis hydropericardium syndrome, and gizzard erosion and ulceration. Inclusion body hepatitis has been regularly reported from many countries. This is the first case report from Turkey, describing an outbreak of inclusion body hepatitis in broiler farms due to fowl adenovirus-8b (FAdV-8b). Broiler flocks with mortality about 10% were visited in Turkey, and necropsy was performed on dead birds. Samples were subjected to PCR assay to detect FAdV and other viral pathogens. After sequencing, phylogenetic analysis was performed and the nucleotide sequences of hexon genes were compared with the FAdV sequences data available in GenBank. Clinical signs such as anorexia, depression, ruffled feathers, huddling, and greenish diarrhoea were observed. Mortality started at the 8ᵗʰ day of age and ranged from 10% to 14%. Necropsy showed severe hepatitis, jaundice, and pancreatitis. The main necropsy findings included a pale, enlarged, haemorrhagic, and friable liver along with swollen and haemorrhagic kidneys and spleen. PCR and sequence analysis revealed the presence of fowl adenovirus serotype 8b (FAdV-E). This is the first report on characterisation and the pathological lesions associated with FAdV in broilers in Turkey. Our findings suggest that FAdV strains could be an emerging pathogen in Turkish broilers and could actively contribute to hepatitis and immunosuppression.
Mostrar más [+] Menos [-]Characterisation of fowl adenovirus (FAdV-8b) strain concerning the geographic analysis and pathological lesions associated with inclusion body hepatitis in broiler flocks in Turkey Texto completo
2020
Cizmecigil Utku Yusuf | Umar Sajid | Yilmaz Aysun | Bayraktar Erhan | Turan Nuri | Tali Besim | Aydin Ozge | Tali Hasan Emre | Yaramanoglu Mehmetcan | Yilmaz Semaha Gul | Kolukisa Ahmet | Sadeyen Jean-Remy | Iqbal Munir | Yilmaz Huseyin
Fowl adenovirus can cause important diseases in chickens such as inclusion body hepatitis, hepatitis hydropericardium syndrome, and gizzard erosion and ulceration. Inclusion body hepatitis has been regularly reported from many countries. This is the first case report from Turkey, describing an outbreak of inclusion body hepatitis in broiler farms due to fowl adenovirus-8b (FAdV-8b).
Mostrar más [+] Menos [-]Identification of infectious bursal disease virus with atypical VP2 amino acid profile in Latvia Texto completo
2017
Identification of infectious bursal disease virus with atypical VP2 amino acid profile in Latvia Texto completo
2017
Introduction: Infectious bursal disease virus (IBDV) is a causative agent of immunosuppressive disorder resulting in significant losses to the world poultry industry. This study describes the molecular characterisation of an atypical IBDV from a field outbreak that occurred in vaccinated chicken flocks in Latvia in 2011.Material and Methods: Ten bursae of Fabricius from each flock were collected for laboratory examination. Virus isolation was performed in embryonated eggs and CEF culture. The RT-PCR aimed at hypervariable domain of VP2 gene combined with sequencing was performed for detection and identification of IBDV.Results: The molecular examinations confirmed the IBDV infection. The analysis of the amino acid sequence revealed that the strain possessed four amino acids at VP2 protein (222A, 256I, 294I, and 299S), indicating a genetic relatedness to a very virulent IBDV. However, some unique or rare amino acid substitutions (219L, 220F, 254D, 279N, and 280T) were also detected.Conclusion: The obtained results demonstrate the occurrence of IBDV with a high mutation rate within the hypervariable domain of VP2 peptide, and highlight the necessity of implementation of IBDV surveillance in Eastern European poultry industry to determine whether this strain is an exception or a new wave of IBDV with new genetic features emerged in the field.
Mostrar más [+] Menos [-]Identification of infectious bursal disease virus with atypical VP2 amino acid profile in Latvia Texto completo
2017
Pikuła Anna | Domańska-Blicharz Katarzyna | Cepulis Rytis | Śmietanka Krzysztof
Introduction: Infectious bursal disease virus (IBDV) is a causative agent of immunosuppressive disorder resulting in significant losses to the world poultry industry. This study describes the molecular characterisation of an atypical IBDV from a field outbreak that occurred in vaccinated chicken flocks in Latvia in 2011.
Mostrar más [+] Menos [-]The protective effects of sonicated Bordetella bronchiseptica bacterin on the immunosuppression of spleen cells induced by anti-cancer drugs (5-fluorouracil, doxorubicin, and vincristine) Texto completo
2022
Lee, Y.J. | Joo, H.G.
5-Fluorouracil, doxorubicin, and vincristine are chemotherapy agents used to treat various cancers, such as breast cancer and lymphoma for decades, and their effects on cancer have been proven. On the other hand, these anti-cancer drugs cause fatal side effects, including immunosuppression. This study investigated whether sonicated Bordetella bronchiseptica bacterin (B. bronchiseptica) can attenuate the immunosuppression of spleen cells induced by these chemotherapy agents and which subsets of spleen cells were affected. B. bronchiseptica increased the metabolic activity of spleen cells treated with 3 anti-cancer drugs. Cell death analysis using Annexin V/propidium iodide showed that B. bronchiseptica markedly decreased the death of spleen cells. The subsets of spleen cells were analyzed by flow cytometry using a surface marker-specific antibody. B. bronchiseptica increased nitric oxide production in the spleen cells treated with anti-cancer drugs (p less than 0.0001). Despite the pharmacological effects of anti-cancer drugs, many patients suffer from the fatal side effects of immunosuppression. This study provides valuable information on how to overcome chemotherapy-induced immunosuppression.
Mostrar más [+] Menos [-]Effects of the monoacylglycerol lipase inhibitor JZL184 on chickens infected with avian pathogenic Escherichia coli O78: A preliminary pharmacokinetic and infection study Texto completo
2020
Ho, Cherry P. | Borazjani, Abdolsamad | Ross, Matthew K. | Wang, Chinling
The endocannabinoid (eCB) system modulates the degree of injury caused by inflammation, while enhancing the activity of phagocytes that promote resolution of inflammation and tissue repair. In-vitro studies with the monoacylglycerol lipase (MAGL) inhibitor JZL184 have suggested that increased eCB signaling might enhance the ability of the host immune system to clear invading pathogens. Although the neurochemical effects of JZL184 on the eCB system in rodents are well-known, its immuneregulating effects are less clear, especially in chickens. The primary objective of this study was to explore whether modulating the eCB system affects immune responses in chickens. To do this, we administered JZL184 [10 and 40 mg/kg body weight (BW), intraperitoneal injection] into chickens prior to a challenge with avian pathogenic Escherichia coli (APEC) O78. Bacteria were isolated from livers, blood, air sacs, and hearts at 8, 28, and 56 h post-infection and the gross lesions in air sacs, livers, and hearts were also examined. Serum levels of JZL184 were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), which indicated that the drug was distributed systemically. The number of birds positive for airsacculitis after APEC O78 challenge was marginally higher in groups treated with JZL184 than in the control group (P = 0.064). Rather than augmenting host defense and enhancing pathogen clearance, these results suggested that JZL184 might have immunosuppressive effects that exacerbated APEC O78 infection in chickens.
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