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Kenneth A. Kudsk - One of the best experts on this subject based on the ideXlab platform.
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Nutritional and Pharmacological Enhancement of the Gut-Associated Lymphoid Tissue
Canadian Journal of Gastroenterology, 2000Co-Authors: M K Hanna, Kenneth A. KudskAbstract:There has been an explosion of research in the field of nutrition over the past quarter century. Clinical studies have demonstrated the effectiveness of providing nutrition by the enteral route in reducing septic morbidity in critically ill patients. These improved outcomes have been substantiated by animal models that show that enteral nutrition decreases gut permeability while maintaining the Gut-Associated Lymphoid Tissue (GALT) in mucosal immunity. Evidence points to the important immunological role of the gut in the maintenance of mucosal immunity at both intestinal and extraintestinal sites. The preservation of this mucosal immunity by enteral nutrition is consistent with the lower morbidity seen in severely injured patients who receive nutrition via the gastrointestinal tract. For patients who are unable to be fed by the enteral route and who require parenteral nutrition, several supplements show promise in enhancing the mucosal immune system defenses. The nutritional and pharmacological tactics that may enhance the GALT and thereby maintain mucosal immunity are examined.
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glycyl l glutamine enriched total parenteral nutrition maintains small intestine gut associated Lymphoid Tissue and upper respiratory tract immunity
Journal of Parenteral and Enteral Nutrition, 1998Co-Authors: Jian Li, Brock K King, Peter G Janu, Kathryn B Renegar, Kenneth A. KudskAbstract:Background: IV administration of a total parenteral nutrition (TPN) solution results in small intestinal Gut-Associated Lymphoid Tissue (GALT) atrophy, lowers small intestinal immunoglobulin A (IgA) levels, and impairs upper respiratory tract secretory IgA-mediated mucosal immunity; isonitrogenous supplementation of TPN with 2% glutamine attenuates these changes. This experiment examines whether a 2% glycyl-L-glutamine-enriched TPN solution reverses IV TPN-induced changes as effectively as L-glutamine. Methods: Male Institute of Cancer Research (ICR) mice underwent intranasal inoculation with H1N1 influenza virus to establish immunity. After 3 weeks, mice were randomized to chow, IV feeding of a TPN solution, glutamine-enriched TPN, or glycyl-L-glutamine-enriched TPN. After 4 days of feeding, mice were challenged intranasally with influenza virus and killed at 40 hours to determine viral shedding from the respiratory tract; normal convalescent mice do not shed virus because they possess intact IgA-mediated mechanisms. Lymphocytes were isolated from Peyer's patches, the intraepithelial layer, and lamina propria to determine cell yields. Results: Total lymphocyte yield in the Peyer's patches, the intraepithelial layer, and lamina propria decreased with TPN but remained normal with glutamine and glycyl-L-glutanine. Upon challenge, 70% of the mice in the TPN group shed virus in nasal secretions, whereas only 20% of the glutamine-treated group, 18% of glycyl-L-glutamine group and none of the Chow group were virus positive. Conclusions: L-Glutamine and glycyl-L-glutamine have similar effects on IV administered TPN-associated (GALT) atrophy and decreased upper respiratory tract immunity.
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Bombesin affects mucosal immunity and Gut-Associated Lymphoid Tissue in intravenously fed mice.
Archives of surgery (Chicago Ill. : 1960), 1995Co-Authors: Kenneth A. Kudsk, Masoud Hamidian, Barbara GocinskiAbstract:Background: Our prior studies show that intravenous (IV) total parenteral nutrition (TPN) produces atrophy of the small intestine–related Gut-Associated Lymphoid Tissue and significant decreases in intestinal IgA levels, the major system of mucosal immunity. Others have noted increased small intestinal permeability, bacterial adherence and translocation, and decreased IgA levels in TPN-fed animals. Bombesin, a neuropeptide, may play a regulatory role in mucosal immunity. It is not clear whether bombesin attenuates the TPN-associated Gut-Associated Lymphoid Tissue atrophy. Objective: To examine the effect of bombesin on gutassociated Lymphoid Tissue integrity and function during IV TPN feeding. Design: Randomized animal study. Setting: A university laboratory. Materials and Methods: Male ICR mice weighing 25 to 30 g were randomized to chow plus IV saline solution (n=12), IV TPN (n=12), or IV TPN plus bombesin (15 μg/kg, administered intramuscularly three times a day) (n=12). Animals were killed after 5 days of receiving the experimental diet. Total small intestinal IgA level was quantified by enzyme-linked immunosorbent assay. Lymphocytes were isolated from Peyer's patches, intraepithelial spaces, and lamina propria and were stained with specific antibodies for B and T cells and for T-cell expression of CD4 CD8 by flow cytometric analysis. Data were analyzed by analysis of variance. Results: Bombesin prevented the IV TPN decreases in (1) total cell yield and B-cell yield from the Peyer's patches, intraepithelial spaces, and lamina propria; (2) T-cell yield in the intraepithelial spaces and lamina propria; and (3) small intestinal IgA levels. Bombesin also reversed IV TPN decreases in CD4+ and CD8+ T cells in the intraepithelial spaces and Peyer's patches and prevented the decrease in the CD4/CD8 ratio in the lamina propria. Conclusion: Bombesin prevents the TPN-associated atrophy and dysfunction of Gut-Associated Lymphoid Tissue, supporting the concept of close neuroimmunologic interaction. (Arch Surg. 1995;130:1164-1170)
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invited review immunologic structure and function of the gastrointestinal tract
Nutrition in Clinical Practice, 1992Co-Authors: Bobbi Langkamphenken, Jeffrey Glezer, Kenneth A. KudskAbstract:Host defenses within the gastrointestinal tract exclude bacteria and other intraluminal substances, which if released into the systemic circulation, would be toxic to the body. This is accomplished via complex interactions between these external pathogens and local immune responses and nonimmunologic processes. In addition to the mechanical and chemical barriers of the nonimmunologic defense system within the gastrointestinal tract, there is an effective immunologic barrier composed of aggregated and nonaggregated Lymphoid cells. Gut-Associated Lymphoid Tissue protects the intestinal mucosa from invading pathogens by intricate pathways of antigen processing. Gut-Associated Lymphoid Tissue also transfers protection to other secretory sites within the body through the common mucosal immune system. The integrity of both the immunologic and nonimmunologic barriers may be affected by any number of pathologic insults as well as by nutritional influences. This article reviews the structural and functional charac...
H F Small - One of the best experts on this subject based on the ideXlab platform.
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preclinical assessment of the distribution of maraviroc to potential human immunodeficiency virus hiv sanctuary sites in the central nervous system cns and gut associated Lymphoid Tissue galt
Xenobiotica, 2008Co-Authors: Don K Walker, S J Bowers, Richard Mitchell, M J Potchoiba, Clinton M Schroeder, H F SmallAbstract:1. Growing knowledge of the pathogenesis of human immunodeficiency virus (HIV)-1 infection has led to the identification of potential virus sanctuary sites within the central nervous system and Gut-Associated Lymphoid Tissue.2. Maraviroc is a novel CCR5 antagonist for the treatment of HIV-1 infection. Disposition studies have been performed within the preclinical testing of maraviroc to determine its distribution to these anatomical sites.3. Maraviroc, which is a substrate of the efflux transporter P-glycoprotein, shows limited distribution to the central nervous system as evidenced by cerebrospinal fluid concentrations that were 10% of the free plasma concentration following intravenous infusion to rats. Tissue distribution studies also indicated limited distribution of radioactivity into brain Tissue of rats.4. Radioactivity in Gut-Associated Lymphoid Tissue lymph nodes exceeded the concentrations in blood and concentrations in the contents of thoracic ducts of the lymphatic system were similar to blood...
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Preclinical assessment of the distribution of maraviroc to potential human immunodeficiency virus (HIV) sanctuary sites in the central nervous system (CNS) and Gut-Associated Lymphoid Tissue (GALT)
Xenobiotica; the fate of foreign compounds in biological systems, 2008Co-Authors: Don K Walker, S J Bowers, M J Potchoiba, Clinton M Schroeder, Richard J. Mitchell, H F SmallAbstract:1. Growing knowledge of the pathogenesis of human immunodeficiency virus (HIV)-1 infection has led to the identification of potential virus sanctuary sites within the central nervous system and Gut-Associated Lymphoid Tissue. 2. Maraviroc is a novel CCR5 antagonist for the treatment of HIV-1 infection. Disposition studies have been performed within the preclinical testing of maraviroc to determine its distribution to these anatomical sites. 3. Maraviroc, which is a substrate of the efflux transporter P-glycoprotein, shows limited distribution to the central nervous system as evidenced by cerebrospinal fluid concentrations that were 10% of the free plasma concentration following intravenous infusion to rats. Tissue distribution studies also indicated limited distribution of radioactivity into brain Tissue of rats. 4. Radioactivity in Gut-Associated Lymphoid Tissue lymph nodes exceeded the concentrations in blood and concentrations in the contents of thoracic ducts of the lymphatic system were similar to blood levels following intravenous administration to rats.
Christine Bourgeois - One of the best experts on this subject based on the ideXlab platform.
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Ageing combines CD4 T cell lymphopenia in secondary Lymphoid organs and T cell accumulation in gut associated Lymphoid Tissue
Immunity & ageing : I & A, 2014Co-Authors: Kim Zita Martinet, Stéphane Bloquet, Christine BourgeoisAbstract:Background CD4 T cell lymphopenia is an important T cell defect associated to ageing. Higher susceptibility to infections, cancer, or autoimmune pathologies described in aged individuals is thought to partly rely on T cell lymphopenia. We hypothesize that such diverse effects may reflect anatomical heterogeneity of age related T cell lymphopenia. Indeed, no data are currently available on the impact of ageing on T cell pool recovered from gut associated Lymphoid Tissue (GALT), a crucial site of CD4 T cell accumulation.
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Ageing combines CD4 T cell lymphopenia in secondary Lymphoid organs and T cell accumulation in gut associated Lymphoid Tissue
Immunity & Ageing, 2014Co-Authors: Kim Martinet, Stéphane Bloquet, Christine BourgeoisAbstract:Background CD4 T cell lymphopenia is an important T cell defect associated to ageing. Higher susceptibility to infections, cancer, or autoimmune pathologies described in aged individuals is thought to partly rely on T cell lymphopenia. We hypothesize that such diverse effects may reflect anatomical heterogeneity of age related T cell lymphopenia. Indeed, no data are currently available on the impact of ageing on T cell pool recovered from gut associated Lymphoid Tissue (GALT), a crucial site of CD4 T cell accumulation. Results Primary, secondary and tertiary Lymphoid organs of C57BL/6 animals were analysed at three intervals of ages: 2 to 6 months (young), 10 to 14 months (middle-aged) and 22 to 26 months (old). We confirmed that ageing preferentially impacted CD4 T cell compartment in secondary Lymphoid organs. Importantly, a different picture emerged from gut associated mucosal sites: during ageing, CD4 T cell accumulation was progressively developing in colon and small intestine lamina propria and Peyer's patches. Similar trend was also observed in middle-aged SJL/B6 F1 mice. Interestingly, an inverse correlation was detected between CD4 T cell numbers in secondary Lymphoid organs and colonic lamina propria of C57BL/6 mice whereas no increase in proliferation rate of GALT CD4 T cells was detected. In contrast to GALT, no CD4 T cell accumulation was detected in lungs and liver in middle-aged animals. Finally, the concomitant accumulation of CD4 T cell in GALT and depletion in secondary Lymphoid organs during ageing was detected both in male and female animals. Conclusions Our data thus demonstrate that T cell lymphopenia in secondary Lymphoid organs currently associated to ageing is not sustained in gut or lung mucosa associated Lymphoid Tissues or non-Lymphoid sites such as the liver. The inverse correlation between CD4 T cell numbers in secondary Lymphoid organs and colonic lamina propria and the absence of overt proliferation in GALT suggest that marked CD4 T cell decay in secondary Lymphoid organs during ageing reflect redistribution of CD4 T cells rather than generalized CD4 T cell decay. Such anatomical heterogeneity may provide an important rationale for the diversity of immune defects observed during ageing.
Natalia Elguezabal - One of the best experts on this subject based on the ideXlab platform.
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Diet induced changes in the microbiota and cell composition of rabbit gut associated Lymphoid Tissue (GALT)
Scientific Reports, 2018Co-Authors: Rakel Arrazuria, Elena Molina, Valentín Pérez, Ehsan Khafipour, Ramon A Juste, Natalia ElguezabalAbstract:The gut associated Lymphoid Tissue (GALT) is the largest immune organ of the body. Although the gut transient and mucosa-associated microbiota have been largely studied, the microbiota that colonizes the GALT has received less attention. The gut microbiome plays an important role in competitive exclusion of pathogens and in development and maturation of immunity. Diet is a key factor affecting the microbiota composition in the digestive tract. To investigate the relation between diet, microbiota and GALT, microbial and cell composition of vermiform appendix (VA) and sacculus rotundus (SR) were studied in two groups of New Zealand white rabbits on different diets. Diet shifted the Lymphoid Tissue microbiota affecting the presence and/or absence of certain taxa and their abundances. Immunohistochemistry revealed that a higher fibre content diet resulted in M cell hyperplasia and an increase of recently recruited macrophages, whereas T-cell levels remained unaltered in animals on both high fibre and standard diets. These findings indicate that diet has an impact on the microbiota and cell composition of the GALT, which could act as an important microbial recognition site where interactions with beneficial bacteria can take place favouring microbiota replacement after digestive dysregulations.
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Detection of Mycobacterium avium subspecies in the gut associated Lymphoid Tissue of slaughtered rabbits
BMC veterinary research, 2015Co-Authors: Rakel Arrazuria, Elena Molina, Ramon A Juste, Iker A. Sevilla, Valentín Pérez Pérez, Joseba M. Garrido, Natalia ElguezabalAbstract:Rabbits are susceptible to infection by different species of the genus Mycobacterium. Particularly, development of specific lesions and isolation of Mycobacterium avium subsp. avium and Mycobacterium avium subsp. paratuberculosis, both subspecies of the M. avium complex, has been reported in wildlife conditions. Although, rabbit meat production worldwide is 200 million tons per year, microbiological data on this source of meat is lacking and more specifically reports of mycobacterial presence in industrially reared rabbit for human consumption have not been published. To this end, we sought mycobacteria by microbiological and histopathological methods paying special attention to Mycobacterium avium subsp. paratuberculosis in rabbits from commercial rabbitries from the North East of Spain. M. avium subsp. paratuberculosis was not detected either by culture or PCR. However, Mycobacterium avium subsp. avium was detected in 15.15 % (10/66) and Mycobacterium avium subsp. hominissuis was detected in 1.51 % (1/66) of gut associated Lymphoid Tissue of sampled animals by PCR, whereas caecal contents were negative. 9 % (6/66) of the animals presented gross lesions suggestive of Lymphoid activation, 6 % (4/66) presented granulomatous lesions and 3 % (2/66) contained acid fast bacilli. Mycobacterial isolation from samples was not achieved, although colonies of Thermoactinomycetes sp. were identified by 16s rRNA sequencing in 6 % (4/66) of sampled animals. Apparently healthy farmed rabbits that go to slaughter may carry M. avium subspecies in gut associated Lymphoid Tissue.
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Detection of Mycobacterium avium subspecies in the gut associated Lymphoid Tissue of slaughtered rabbits
BMC Veterinary Research, 2015Co-Authors: Rakel Arrazuria, Elena Molina, Valentín Pérez, Ramon A Juste, Iker A. Sevilla, Joseba M. Garrido, Natalia ElguezabalAbstract:Background Rabbits are susceptible to infection by different species of the genus Mycobacterium . Particularly, development of specific lesions and isolation of Mycobacterium avium subsp. avium and Mycobacterium avium subsp. paratuberculosis , both subspecies of the M. avium complex, has been reported in wildlife conditions. Although, rabbit meat production worldwide is 200 million tons per year, microbiological data on this source of meat is lacking and more specifically reports of mycobacterial presence in industrially reared rabbit for human consumption have not been published. To this end, we sought mycobacteria by microbiological and histopathological methods paying special attention to Mycobacterium avium subsp. paratuberculosis in rabbits from commercial rabbitries from the North East of Spain. Results M. avium subsp. paratuberculosis was not detected either by culture or PCR. However, Mycobacterium avium subsp. avium was detected in 15.15 % (10/66) and Mycobacterium avium subsp. hominissuis was detected in 1.51 % (1/66) of gut associated Lymphoid Tissue of sampled animals by PCR, whereas caecal contents were negative. 9 % (6/66) of the animals presented gross lesions suggestive of Lymphoid activation, 6 % (4/66) presented granulomatous lesions and 3 % (2/66) contained acid fast bacilli. Mycobacterial isolation from samples was not achieved, although colonies of Thermoactinomycetes sp. were identified by 16s rRNA sequencing in 6 % (4/66) of sampled animals. Conclusions Apparently healthy farmed rabbits that go to slaughter may carry M. avium subspecies in gut associated Lymphoid Tissue.
Don K Walker - One of the best experts on this subject based on the ideXlab platform.
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preclinical assessment of the distribution of maraviroc to potential human immunodeficiency virus hiv sanctuary sites in the central nervous system cns and gut associated Lymphoid Tissue galt
Xenobiotica, 2008Co-Authors: Don K Walker, S J Bowers, Richard Mitchell, M J Potchoiba, Clinton M Schroeder, H F SmallAbstract:1. Growing knowledge of the pathogenesis of human immunodeficiency virus (HIV)-1 infection has led to the identification of potential virus sanctuary sites within the central nervous system and Gut-Associated Lymphoid Tissue.2. Maraviroc is a novel CCR5 antagonist for the treatment of HIV-1 infection. Disposition studies have been performed within the preclinical testing of maraviroc to determine its distribution to these anatomical sites.3. Maraviroc, which is a substrate of the efflux transporter P-glycoprotein, shows limited distribution to the central nervous system as evidenced by cerebrospinal fluid concentrations that were 10% of the free plasma concentration following intravenous infusion to rats. Tissue distribution studies also indicated limited distribution of radioactivity into brain Tissue of rats.4. Radioactivity in Gut-Associated Lymphoid Tissue lymph nodes exceeded the concentrations in blood and concentrations in the contents of thoracic ducts of the lymphatic system were similar to blood...
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Preclinical assessment of the distribution of maraviroc to potential human immunodeficiency virus (HIV) sanctuary sites in the central nervous system (CNS) and Gut-Associated Lymphoid Tissue (GALT)
Xenobiotica; the fate of foreign compounds in biological systems, 2008Co-Authors: Don K Walker, S J Bowers, M J Potchoiba, Clinton M Schroeder, Richard J. Mitchell, H F SmallAbstract:1. Growing knowledge of the pathogenesis of human immunodeficiency virus (HIV)-1 infection has led to the identification of potential virus sanctuary sites within the central nervous system and Gut-Associated Lymphoid Tissue. 2. Maraviroc is a novel CCR5 antagonist for the treatment of HIV-1 infection. Disposition studies have been performed within the preclinical testing of maraviroc to determine its distribution to these anatomical sites. 3. Maraviroc, which is a substrate of the efflux transporter P-glycoprotein, shows limited distribution to the central nervous system as evidenced by cerebrospinal fluid concentrations that were 10% of the free plasma concentration following intravenous infusion to rats. Tissue distribution studies also indicated limited distribution of radioactivity into brain Tissue of rats. 4. Radioactivity in Gut-Associated Lymphoid Tissue lymph nodes exceeded the concentrations in blood and concentrations in the contents of thoracic ducts of the lymphatic system were similar to blood levels following intravenous administration to rats.