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You searched for subject:(Lymphocyte proliferation assay). Showing records 1 – 3 of 3 total matches.

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Virginia Tech

1. Lewis, Stephanie Rochelle. Experimental infection with Sarcocystis neurona alters the immune response: the effect on CD4+, CD8+, B-cell, monocyte and granulocyte populations in horses.

Degree: MS, Veterinary Medical Sciences, 2009, Virginia Tech

Previous studies have demonstrated differences in CD4+, CD8+ and B-cell populations between EPM affected and normal horses. The overall goal of our project was to further define the immune deficiencies associated with S. neurona infection. We hypothesized that PMA/I stimulated suppression in EPM horses is due to decreased proliferation of monocytes, CD4+ and CD8+ cells. Our objectives were 1) to determine whether S. neurona infection causes an increase in apoptosis of a particular immune subset, and 2) to determine whether S. neurona causes a decrease in the number of cellular divisions (proliferation) of a particular immune cell subset. For this study, nine S. neurona antibody negative, immunocompetent horses were obtained. Baseline neurologic examinations, SnSAG1 (S. neurona Surface Antigen 1) ELISAs on cerebrospinal fluid (CSF) and serum, and baseline immune function assays were performed. Horses were randomly divided into groups. Five horses were challenged for ten days via intravenous injection of autologous lymphocytes infected with S. neurona. Neurologic parameters of all horses were assessed for 70 days following infection. Immune function was based on proliferation responses to mitogens, as assessed through thymidine incorporation. Enumeration of cellular subsets, degree of apoptosis and number of cellular divisions were assessed through flow cytometry. SnSAG1 ELISA of serum and CSF samples performed post-infection confirmed infection and disease. All infected horses displayed moderate neurologic signs on clinical examination. Some significant differences in cellular activities were noted. Additionally, this is the first time the method using S. neurona infected lymphocytes has been reproduced successfully by different investigators. Advisors/Committee Members: Witonsky, Sharon G. (committeechair), Lindsay, David S. (committee member), Virginia A Buechner-Maxwell (committee member), Dascanio, John J. (committee member), Gogal, Robert M. (committee member).

Subjects/Keywords: Horse; Equine Protozoal Myeloencephalitis; EPM; Sarcocystis neurona; immune response; lymphocyte proliferation assay

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Lewis, S. R. (2009). Experimental infection with Sarcocystis neurona alters the immune response: the effect on CD4+, CD8+, B-cell, monocyte and granulocyte populations in horses. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/33919

Chicago Manual of Style (16th Edition):

Lewis, Stephanie Rochelle. “Experimental infection with Sarcocystis neurona alters the immune response: the effect on CD4+, CD8+, B-cell, monocyte and granulocyte populations in horses.” 2009. Masters Thesis, Virginia Tech. Accessed August 03, 2020. http://hdl.handle.net/10919/33919.

MLA Handbook (7th Edition):

Lewis, Stephanie Rochelle. “Experimental infection with Sarcocystis neurona alters the immune response: the effect on CD4+, CD8+, B-cell, monocyte and granulocyte populations in horses.” 2009. Web. 03 Aug 2020.

Vancouver:

Lewis SR. Experimental infection with Sarcocystis neurona alters the immune response: the effect on CD4+, CD8+, B-cell, monocyte and granulocyte populations in horses. [Internet] [Masters thesis]. Virginia Tech; 2009. [cited 2020 Aug 03]. Available from: http://hdl.handle.net/10919/33919.

Council of Science Editors:

Lewis SR. Experimental infection with Sarcocystis neurona alters the immune response: the effect on CD4+, CD8+, B-cell, monocyte and granulocyte populations in horses. [Masters Thesis]. Virginia Tech; 2009. Available from: http://hdl.handle.net/10919/33919


Virginia Tech

2. Goehring, Lutz Steffen. Equine Protozoal Myeloencephalitis. Preliminary Investigation of Protozoan-Host interactions in the horse.

Degree: MS, Veterinary Medical Sciences, 1998, Virginia Tech

Equine Protozoal Myeloencephalitis is the most frequently diagnosed neurologic disorder of horses in the united states, which is caused by the protozoan organism Sarcocystis neurona. The disease has a profound impact on the American Horse Industry. This impact includes prolonged and expensive treatment without a guaranteed return to a previous level of use for the individual horse. Poor respponse to and prolonged duration of treatment may suggest an immune mediated impariement of host response. There is limited information about the direct interaction between the pathogen and the host. In two in vitro experiments we investigated a) whether the presence of the protozoan organism can influence mitogen-stimulated peripheral blood mononuclear cells (PBMCs), suggesting a direct influence of the protozoan organism on cells of the immune system, and b) if cerebrospinal fluid (CSF) from horses with EPM has an effect on mitogen-stimulated PBMCs, suggesting that the microenvironment of the site of infection influences the course of disease. Experiment 1: Mitogen simulated PBMCs from EPM affected and control horses were co-cultured with fragments of freeze thawed bovine turbinate cells that were infected with S. neurona merozoites. Compared to controls PBMCs co-cultured with S. neurona fragments were the only cells that showed a decreased proliferation (p<0.05). A difference between EPM affected and control horses could not be detected (p>0.05). These results may imply that the persistence of S. neurona infection in the horses CNS is, in part, due to a pathogen-derived mechanism that attentuates the hosts immune response. Experiment 2: Mitogen stimulated PBMCs from a horse affected with EPM and a control were co-cultured n the presence of CSF from EPM affected and uninfected controls. Prior to co-culture the CSF was fractionated by a filtration process over two microfilter units. An identical volume of NaCl (0.9%) served as a control for the volume of CSF that was added. The proliferation assay revealed a deviation of the response depending on cell donor and CSF fraction used. The effect was independant of the protein concentration of the CSF fraction, and a decrease in lymphocyte proliferation was not caused by increased cellular death. This suggests the presence of subsets within the CSF which have a stimulatory of suppressive influence on the cells in culture. The effect was cell donor dependant which implies a difference in lymphocyte subsets between the two horses that were used. Advisors/Committee Members: Furr, Martin O. (committeechair), Buechner-Maxwell, Virginia A. (committee member), Ahmed, S. Ansar (committee member).

Subjects/Keywords: Sarcocystis neurona; Equine Protozoal Myeloencephalitis; immune priviledged site; Lymphocyte proliferation assay; Horse

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Goehring, L. S. (1998). Equine Protozoal Myeloencephalitis. Preliminary Investigation of Protozoan-Host interactions in the horse. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/45145

Chicago Manual of Style (16th Edition):

Goehring, Lutz Steffen. “Equine Protozoal Myeloencephalitis. Preliminary Investigation of Protozoan-Host interactions in the horse.” 1998. Masters Thesis, Virginia Tech. Accessed August 03, 2020. http://hdl.handle.net/10919/45145.

MLA Handbook (7th Edition):

Goehring, Lutz Steffen. “Equine Protozoal Myeloencephalitis. Preliminary Investigation of Protozoan-Host interactions in the horse.” 1998. Web. 03 Aug 2020.

Vancouver:

Goehring LS. Equine Protozoal Myeloencephalitis. Preliminary Investigation of Protozoan-Host interactions in the horse. [Internet] [Masters thesis]. Virginia Tech; 1998. [cited 2020 Aug 03]. Available from: http://hdl.handle.net/10919/45145.

Council of Science Editors:

Goehring LS. Equine Protozoal Myeloencephalitis. Preliminary Investigation of Protozoan-Host interactions in the horse. [Masters Thesis]. Virginia Tech; 1998. Available from: http://hdl.handle.net/10919/45145


Virginia Tech

3. Yang, Jibing. Investigation of Immune Response to Sarcocystis neurona Infection in Horses with Equine Protozoal Myeloencephalitis.

Degree: MS, Veterinary Medical Sciences, 2005, Virginia Tech

Equine Protozoal Myeloencephalitis (EPM) is a serious neurologic disease of horses in the United States. The primary etiologic agent is Sarcocystis neurona (S. neurona). Currently, there is limited knowledge regarding the protective or pathologic immune response to infection to the intracellular protozoa S. neurona. The objective of these studies was to determine the effects of S. neurona infection on the immune response of horses that had EPM due to natural infection (experiment 1) and experimental infection (experiment 2). In experiment 1, twenty-two horses with naturally occurring cases of EPM, which were confirmed positive based on detection of antibodies in the serum and/or CSF and clinical signs, and 20 clinically normal horses were included to determine whether S. neurona altered the immune responses, as measured by immune cell subsets (CD4, CD8, B-cell, monocytes, and neutrophils) and leukocyte proliferation (antigen specific and non-specific mitogens). Our results demonstrated that naturally infected horses had significantly higher percentages of CD4 and neutrophils (PMN) in peripheral blood mononuclear cells (PBMCs) than clinically normal horses. Leukocytes from naturally infected EPM horses had a significantly lower proliferation response, as measured by thymidine incorporation, to a non-antigen specific mitogen phorbol 12-myristate 13-acetate (PMA) / ionomycin (I) than did clinically normal horses (p=0.04). The implications of these findings will be discussed. In experiment 2, 13 horses were randomly divided into two groups. Baseline neurologic examinations were performed and all horses were confirmed negative for S. neurona antibodies in the CSF and serum. Then, one group with 8 clinically normal seronegative horses was inoculated intravenously with approximately 6000 S. neurona infected autologous leukocytes daily for 14 days. All the challenged horses showed neurologic signs consistent with EPM. PBMCs were isolated from the control and infected horses to determine how S. neurona alters the immune responses based on changes in immune cell subsets and immune function. There were no significant differences in the percentage of CD4 cells in peripheral blood lymphocytes or IFN-γ production by CD4 and/or CD8 cells. PMA/I stimulated proliferation responses in PBMCs appeared suppressed compared to that of uninfected controls. Additional studies are necessary to determine the role of CD4 and CD8 cells in disease and protection to S. neurona in horses, as well as to determine the mechanism associated with suppressed in vitro proliferation responses. This project was funded by Patricia Stuart Equine grants and paramutual racing funds from Virginia Tech. Advisors/Committee Members: Witonsky, Sharon G. (committeechair), Gogal, Robert M. Jr. (committee member), Lindsay, David S. (committee member), Sriranganathan, Nammalwar (committee member), Suzuki, Yasuhiro (committee member).

Subjects/Keywords: lymphocyte proliferation assay; immune response; Sarcocystis neurona; EPM; IFN-γ; Horse; Equine Protozoal Myeloencephalitis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Yang, J. (2005). Investigation of Immune Response to Sarcocystis neurona Infection in Horses with Equine Protozoal Myeloencephalitis. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/34205

Chicago Manual of Style (16th Edition):

Yang, Jibing. “Investigation of Immune Response to Sarcocystis neurona Infection in Horses with Equine Protozoal Myeloencephalitis.” 2005. Masters Thesis, Virginia Tech. Accessed August 03, 2020. http://hdl.handle.net/10919/34205.

MLA Handbook (7th Edition):

Yang, Jibing. “Investigation of Immune Response to Sarcocystis neurona Infection in Horses with Equine Protozoal Myeloencephalitis.” 2005. Web. 03 Aug 2020.

Vancouver:

Yang J. Investigation of Immune Response to Sarcocystis neurona Infection in Horses with Equine Protozoal Myeloencephalitis. [Internet] [Masters thesis]. Virginia Tech; 2005. [cited 2020 Aug 03]. Available from: http://hdl.handle.net/10919/34205.

Council of Science Editors:

Yang J. Investigation of Immune Response to Sarcocystis neurona Infection in Horses with Equine Protozoal Myeloencephalitis. [Masters Thesis]. Virginia Tech; 2005. Available from: http://hdl.handle.net/10919/34205

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