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Tuo W, Zarlenga D, Bakshi M, Vinyard B. Repeated, drug-truncated infections with Ostertagia ostertagi elicit strong humoral and cell-mediated immune responses and confer partial protection in cattle. Vet Parasitol 2021; 296:109510. [PMID: 34217073 DOI: 10.1016/j.vetpar.2021.109510] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 06/23/2021] [Accepted: 06/24/2021] [Indexed: 10/21/2022]
Abstract
Bovine ostertagiasis causes significant production losses to the cattle industry. Protective immunity induced by natural infection is slow to develop and anthelmintic resistance is rapidly developing. There is a need to advance alternatives for control of gastrointestinal nematode parasites. The present study investigated the effects of repeated, drug-truncated infections (rDTI) on development of protective immunity and attenuation of a challenge infection by O. ostertagi. Helminth-free calves were randomly assigned to either a rDTI or a control group (n = 5). The rDTI group received daily oral infections of 5000 Ostertagia L3 for 5 consecutive days, then were drug-treated on 14 and 15 days post infection (dpi), to attenuate O. ostertagi at the late fourth larval (L4) through young adult stages. DTI was repeated 3 weeks after the drug treatment. A total of 5 DTIs were administered to the DTI-treated animals. Non-DTI-treated, control animals received tap water as infection control. All animals were drug-treated at the same time. Animals were challenge-infected 4 weeks following the final round of rDTI. The results show that eggs per gram of feces (EPG) in the rDTI group were significantly reduced (P < 0.05) from 21 to 39 dpi, with an overall reduction in cumulative EPG. The control group exhibited reduced (P = 0.0564) average weight gains when compared to those of the rDTI group during weeks 4-5 post infection, a period coinciding with peak EPG output of control animals. Antigen-specific IgG, IgE and IgA responses were detected after the 2nd DTI, and stronger antibody recall responses were elicited by challenge infection. High levels of antigen-specific peripheral blood mononuclear cell (PBMC)/T cell proliferation to whole worm and excretory-secretory (ES) antigens were detected in rDTI-treated animals. These data indicate that partial protective immunity against ostertagiasis, involving cell-mediated and humoral responses, can be attained by rDTI which allowed for maximal antigen exposure from staggered parasitic developmental stages. The data suggest that rDTI can be used as a model to study host-parasite interactions and identify parasite antigens responsible for eliciting host protective immune responses.
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Affiliation(s)
- Wenbin Tuo
- Animal Parasitic Diseases Lab, USDA/ARS, Beltsville, MD 20705, USA.
| | - Dante Zarlenga
- Animal Parasitic Diseases Lab, USDA/ARS, Beltsville, MD 20705, USA
| | - Mariam Bakshi
- Animal Parasitic Diseases Lab, USDA/ARS, Beltsville, MD 20705, USA
| | - Bryan Vinyard
- Statistics Group, Northeast Area Office of the Director, USDA/ARS, Beltsville, MD 20705, USA
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Ostertagia ostertagi Mediates Early Host Immune Responses via Macrophage and Toll-Like Receptor Pathways. Infect Immun 2021; 89:IAI.00017-21. [PMID: 33685941 DOI: 10.1128/iai.00017-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 02/25/2021] [Indexed: 11/20/2022] Open
Abstract
Ostertagia ostertagi is an abomasal parasite with significant economic impact on the cattle industry. Early host immune responses are poorly understood. Here, we examined time course expression of Toll-like receptors (TLRs) in peripheral blood mononuclear cells (PBMC) during infection where PBMC macrophages (Mϕ) generated both pro- and anti-inflammatory responses when incubated with excretory/secretory products (ESP) from fourth-stage larvae (OoESP-L4) or adult worms (OoESP-Ad). First, changes in cell morphology clearly showed that both OoESP-L4 and OoESP-Ad activated PBMC-Mϕ in vitro, resulting in suppressed CD40 and increased CD80 expression. Expression of mRNAs for TLR1, -4, -5, and -7 peaked 7 days postinfection (dpi) (early L4), decreased by 19 dpi (postemergent L4 and adults) and then increased at 27 dpi (late adults). The proinflammatory cytokine tumor necrosis factor alpha (TNF-α) (transcript and protein) increased in the presence of OoESP-Ad, and the anti-inflammatory cytokine interleukin 10 (IL-10) (protein) decreased in the presence of OoESP-L4 or OoESP-Ad; however, IL-10 mRNA was upregulated, and IL-6 (protein) was downregulated by OoESP-L4. When PBMC-Mϕ were treated with ligands for TLR4 or TLR5 in combination with OoESP-Ad, the transcripts for TNF-α, IL-1, IL-6, and IL-10 were significantly downregulated relative to treatment with TLR4 and TLR5 ligands only. However, the effects of TLR2 ligand and OoESP-Ad were additive, but only at the lower concentration. We propose that O. ostertagi L4 and adult worms utilize competing strategies via TLRs and Mϕ to confuse the immune system, which allows the worm to evade the host innate responses.
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Magdálek J, Makovický P, Vadlejch J. Nematode-induced pathological lesions and alterations of mucin pattern identified in abomasa of wild ruminants. INTERNATIONAL JOURNAL FOR PARASITOLOGY-PARASITES AND WILDLIFE 2021; 14:62-67. [PMID: 33520647 PMCID: PMC7820933 DOI: 10.1016/j.ijppaw.2020.12.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 12/11/2020] [Accepted: 12/18/2020] [Indexed: 12/19/2022]
Abstract
Pathological lesions as well as mucin alterations in abomasa infected by nematodes have been thoroughly studied in livestock, but such data from wild ruminants are limited or completely lacking. Pathological data for Ashworthius sidemi, an invasive nematode are particularly rare. We necropsied the abomasa of 21 wild ruminants belonging to five cervid species and detected mixed nematode infections, dominated by A. sidemi. Samples from both gross lesions and mucous membranes without macroscopically apparent pathological alterations were subjected to standard histological procedures and histochemical staining. Histological examination found chronic abomasitis, manifested by edema, and hyperemia. Various degrees of lymphoplasmacytic infiltration were observed in all samples. Initial fibrosis (8/20, 40%) was detected in samples from both gross lesions and areas without macroscopically visible changes. Tissue from hemorrhagic lesions was superficially eroded. Generalized loss of surface polysaccharides was apparent in all samples. Only residual periodic acid-Schiff and Alcian blue (pH2.5) positivity was detected in the upper abomasal pits and in mucosal neck. This study found that nematode infections, mostly by A. sidemi, caused chronic inflammation and negatively affected abomasal mucin formation in wild ruminants. Histological examination of tissue samples identified nematode-induced abomasitis. Loss of superficial polysaccharides was apparent in all tissue samples. Mainly acidic residual mucins were detected in abomasal pits and mucosal neck zone.
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Affiliation(s)
- Jan Magdálek
- Department of Zoology and Fisheries, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00, Prague, Suchdol, Czech Republic
| | - Pavol Makovický
- J. Selye University, Faculty of Education, Department of Biology, Bratislavska 3322, 945 01, Komarno, Slovak Republic
| | - Jaroslav Vadlejch
- Department of Zoology and Fisheries, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00, Prague, Suchdol, Czech Republic
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Characterization of IL-10-producing neutrophils in cattle infected with Ostertagia ostertagi. Sci Rep 2019; 9:20292. [PMID: 31889109 PMCID: PMC6937330 DOI: 10.1038/s41598-019-56824-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 12/17/2019] [Indexed: 02/07/2023] Open
Abstract
IL-10 is a master regulator of immune responses, but its cellular source and function in cattle during the initial phase of immune priming have not been well established. Despite a massive B cell response in the abomasal draining lymph nodes in Ostertagia ostertagi (OO)-infected cattle, protective immunity is slow to develop, and partial protection requires years of repeated exposure. In addressing this problem, our initial hypothesis was that B cells produce IL-10 that downregulates the host protective immune response. However, our results showed that neutrophils made up the majority of IL-10-producing cells in circulation and in secondary lymphoid tissues, particularly the spleen (80%). Conversely, IL-10-producing B cells were rare. In addition, approximately 10% to 20% of the neutrophils in the blood and spleen expressed MHC II and were IL-10 negative, suggesting that neutrophils could also participate in antigen presentation. In vitro investigation of bovine neutrophils revealed that exposure thereof to OO extract increased IL-10 and MHC II expression in these cells in a dose-dependent manner, consistent with IL-10+/MHC II+ neutrophils detected in cattle shortly after experimental OO infection. Co-culture of untreated neutrophils with anti-CD3 antibody (Ab)-stimulated CD4+ T cells led to enhanced T cell activation; also, IL-10 depletion with neutralizing Ab enhanced the stimulatory function of neutrophils. OO extract depressed neutrophil stimulation of CD4+ T cells in the presence of IL-10-neutralizing Ab, suggesting that OO utilizes both IL-10-dependent and independent mechanisms to manipulate the bovine immune response. Finally, contact and viability were required for T cell-stimulatory neutrophil function. This report, to the best of our knowledge, is the first to demonstrate that neutrophil-derived IL-10 is directly involved in T cell regulation in cattle. Our data suggest that neutrophils and neutrophil-derived IL-10 are co-opted by nematode parasites and other pathogens to attenuate host immune responses and facilitate pathogen survival.
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Mihi B, van Meulder F, Vancoppernolle S, Rinaldi M, Chiers K, van den Broeck W, Goddeeris BM, Vercruysse J, Claerebout E, Geldhof P. Analysis of the mucosal immune responses induced by single and trickle infections with the bovine abomasal nematode Ostertagia ostertagi. Parasite Immunol 2014; 36:150-6. [PMID: 24372091 DOI: 10.1111/pim.12094] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Accepted: 12/13/2013] [Indexed: 12/11/2022]
Abstract
The purpose of this study was to provide more information on the kinetics of the immunological changes occurring in the abomasal mucosa after single and trickle infections with the bovine parasite Ostertagia ostertagi. The time course analysis of gene expression revealed that the major changes coincided with the emergence of adult worms from the gastric glands. These changes consisted of a simultaneous upregulation of Th1- and Th2-type cytokines. In addition, a single O. ostertagi infection elicited an upregulation of the epithelial-derived cytokine IL33, while TSLP expression levels were not impacted. Apart from the massive increase in inflammatory cytokines IL6, IL17 and IL21, O. ostertagi infection also elicited an upregulation of the immunosuppressors TGFB, IL10 and ARG1, as well as NK and γδ-T cell markers. Furthermore, the cytotoxic factors granulysin, perforin and granzyme B were upregulated following an O. ostertagi infection. Analysis of cytokine transcript levels in animals receiving trickle infections for 60 days showed a similar trend as observed following a single infection except for IL33, IL6, GATA-3, TBX21 and NCR1, which were no longer upregulated after trickle infections. Finally, the long trickle infections were associated with mucosal eosinophilia and mastocytosis.
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Affiliation(s)
- B Mihi
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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RINALDI M, GELDHOF P. Immunologically based control strategies for ostertagiosis in cattle: where do we stand? Parasite Immunol 2012; 34:254-64. [DOI: 10.1111/j.1365-3024.2011.01313.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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7
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Cellular Phenotypes in the Abomasal Mucosa and Abomasal Lymph Nodes of Goats Infected with Haemonchus contortus. J Comp Pathol 2008; 138:102-7. [DOI: 10.1016/j.jcpa.2007.11.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Accepted: 11/27/2007] [Indexed: 11/22/2022]
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Infectious and Parasitic Diseases of the Alimentary Tract. JUBB, KENNEDY & PALMER'S PATHOLOGY OF DOMESTIC ANIMALS 2007. [PMCID: PMC7155580 DOI: 10.1016/b978-070202823-6.50096-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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9
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Stromberg BE, Gasbarre LC. Gastrointestinal Nematode Control Programs with an Emphasis on Cattle. Vet Clin North Am Food Anim Pract 2006; 22:543-65. [PMID: 17071352 DOI: 10.1016/j.cvfa.2006.08.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Control strategies for nematode parasites rely on knowledge of the relationships between the parasites and their hosts. Specifically, these programs are based on identifying crucial points of interaction in the environment provided by the host, including genetics and the immune response, and critical periods in the physical environment in which the eggs and larval stages must develop. When these targets are identified and the interactions understood, cost-effective sustainable programs can be developed using currently available antiparasitic compounds. Resistance to the major classes of anthelmintic compounds requires consideration of new approaches, such as immunity or genetics of the host. Additionally, the efficacy of these compounds can be expanded with combined or concomitant use. Increased study of the use of novel approaches, including fungi, elements such as copper, and plant products, has also occurred. This article explores each of these areas to allow readers to appreciate how various approaches may be developed and incorporated into an effective parasite control program.
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Affiliation(s)
- Bert E Stromberg
- Veterinary and Biomedical Sciences Department, College of Veterinary Medicine, University of Minnesota, 1971 Commonwealth Avenue, St. Paul, MN 55108, USA.
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Pasquali P, Fayer R, Zarlenga D, Canals A, Marez TD, Gomez Munoz MT, Almeria S, Gasbarre LC. Recombinant bovine interleukin-12 stimulates a gut immune response but does not provide resistance to Cryptosporidium parvum infection in neonatal calves. Vet Parasitol 2006; 135:259-68. [PMID: 16386849 DOI: 10.1016/j.vetpar.2005.05.062] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2004] [Revised: 05/20/2005] [Accepted: 05/28/2005] [Indexed: 12/21/2022]
Abstract
This study was undertaken to determine if administration of recombinant bovine interleukin-12 (rBoIL-12) could stimulate a cellular immune response that protected calves from an oral challenge inoculation with Cryptosporidium parvum oocysts. In a first experiment, rBoIL-12 intraperitoneally administered as a single dose 1 day before challenge inoculation, did not alter the course of infection. The percentage of immune competent cells and levels of cytokine gene expression in the ileo-cecal mucosa and in the draining lymph nodes of treated calves were similar to those of untreated control calves. However, when rBoIL-12 was subcutaneously administered daily from 2 days before infection to 2 days after infection, a consistent increase of T lymphocytes and an higher expression of interferon-gamma (IFN-gamma) was detected. Again, treatment did not alter the course of infection. Similar results were obtained when rBoIL-12 was administered daily for 4 days beginning 2 days after oral inoculation. These data indicate that although rBoIL-12 stimulated a strong immune response in the gut of neonatal calves, the response was not able to provide protection from challenge inoculation with C. parvum oocysts.
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Affiliation(s)
- Paolo Pasquali
- Istituto Superiore di Sanita', Department of Food Safety and Veterinary Public Health, Rome, Italy
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Gómez-Muñoz MT, Canals-Caballero A, Almeria S, Pasquali P, Zarlenga DS, Gasbarre LC. Inhibition of bovine T lymphocyte responses by extracts of the stomach worm Ostertagia ostertagi. Vet Parasitol 2004; 120:199-214. [PMID: 15041095 DOI: 10.1016/j.vetpar.2004.01.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2003] [Accepted: 01/14/2004] [Indexed: 11/17/2022]
Abstract
Lowered immune responses during bovine ostertagiosis have been reported in both in vivo and in vitro assay systems. In the present study we have employed three different life cycle stages of the nematode Ostertagia ostertagi to determine if products of this economically important parasite inhibit in vitro proliferation of Con A-stimulated cells from uninfected animals. We have demonstrated an inhibitory effect upon the growth of Con A-stimulated lymphocytes after addition of fourth stage larval (L4) soluble extract (L4SE) to the cultures. In contrast, extracts from the third stage larvae (L3) had little or no inhibitory activity. The suppressive products were also shown to be secreted by the late L4. The suppressive activity is reversible if the L4 products are removed from culture. There is no immediate effect on proliferating cells and the L4SE must be in culture for 24-48 h before suppression is observable. The L4SE caused slight but not statistically significant decreases in the percentage of T cells and increases in B cell percentages in cultures when compared with cultures stimulated with Con A alone. No changes were seen in percentage of cells positive for markers for CD4, CD8, gammadelta T cells, or monocytes/macrophages as a consequence of the addition of L4SE. In contrast, there was a strong and significant reduction in the expression of the IL-2 receptors in cells cultured in the presence of the worm extract. There was no evidence of either necrosis or apoptosis resulting from the presence of L4 products in culture. The expression of messenger RNA for interleukin-2, -4, -13, tumor necrosis factor-alpha (TNF-alpha), and gamma-interferon (gamma-IFN) was decreased when L4SE was included in cultures of Con A-stimulated cells compared to cultures stimulated with Con A only. In contrast, messenger RNA expression of transforming growth factor-beta (TGF-beta) and interleukin-10 (IL-10) was increased in cells growing in the presence of L4 products. The potential role of these cytokines during ostertagiosis is discussed.
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Affiliation(s)
- M T Gómez-Muñoz
- Departamento de Atención Sanitaria, Salud Pública y Sanidad Animal, Facultad de Ciencias Experimentales y de la Salud, Universidad Cardenal Herrera-CEU, Valencia, Spain.
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12
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Almeria S, De Marez T, Dawson H, Araujo R, Dubey JP, Gasbarre LC. Cytokine gene expression in dams and foetuses after experimental Neospora caninum infection of heifers at 110 days of gestation. Parasite Immunol 2004; 25:383-92. [PMID: 14521581 DOI: 10.1046/j.1365-3024.2003.00645.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Neospora caninum is a major cause of abortion in cattle. An essential role for Th1 cytokines, such as IFN-gamma and IL-12 in protective immunity against N. caninum in murine models has been indicated. However, little is known about immunity to Neospora in pregnant cattle where a considerable level of immunomodulation may exist. In this study, the immune response of heifers infected early in the second trimester of pregnancy by intravenous inoculation of N. caninum tachyzoites was compared with immune responses in uninfected pregnant heifers. Animals were killed 3 weeks after infection. No abortion was observed in any infected dam, however, transplacental infection was shown to have already taken place. Infection with N. caninum during pregnancy induced significant immune responses in both dams and their foetuses. Infected dams showed significant changes in lymphocyte subpopulations compared with uninfected pregnant animals and these changes were compartmentalized. Increased levels of T lymphocytes were observed in the infected foetuses. Cytokine gene expression analysed by real time RT-PCR showed increased expression of both Th1 and Th2 cytokines in N. caninum infected animals. This cytokine expression could have a role in the transplacental transmission of the parasite and/or mediate tissue damage.
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Affiliation(s)
- S Almeria
- Parasitology, Veterinary School, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain
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Kanobana K, Koets A, Kooyman FNJ, Bakker N, Ploeger HW, Vervelde L. B cells and antibody response in calves primary-infected or re-infected with Cooperia oncophora: influence of priming dose and host responder types. Int J Parasitol 2003; 33:1487-502. [PMID: 14572512 DOI: 10.1016/s0020-7519(03)00210-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We investigated whether the generation of protective memory humoral immunity in Cooperia oncophora infected calves occurs in a dose-dependent way and whether it depends on the animal responder types. To this end, serum and mucus antibody responses were measured in animals primary-infected with 30000 or 100000 L3, treated with anthelmintics and subsequently challenged with 100000 L3. A detailed phenotypic and functional analysis of B cells was done in animals infected once or twice with 100,000 L3. Based on the similarity in parasitological variables of animals primed with 30000 or 100000 L3, we concluded that with these doses priming conferred protection in a dose-independent way. Upon challenge significant increases in Cooperia-specific serum and mucus IgG1 and IgA and total serum IgE titres were induced in primed animals in a dose-independent way. In contrast, intermediate and low responders differed in the onset of the production of Cooperia-specific serum IgG1. Furthermore, not only the onset but also the level of total serum IgE significantly differed between intermediate and low responders. Phenotypic and functional analysis of B lymphocytes revealed that (i). priming induced the generation of memory B cells which upon challenge readily differentiated into antibody secreting cells; (ii). sensitised B cells were more efficiently recruited to the intestinal effector sites; (iii). based on the expression of CD62L and CD86 two distinct B cell subpopulation could be differentiated. CD62L(+)CD86(-) B cells that were likely lymphocytes not yet activated and with an enhanced recirculation capacity, and CD62L(-)CD86(+) B cells that were activated B cells with a reduced recirculation ability; and finally (iv). the increased expression of CD86 and subsequent correlations with parameters of the T helper 2 immune response induced by C. oncophora, suggested that CD86- interactions are involved in the generation of protective immunity against Cooperia.
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Affiliation(s)
- K Kanobana
- Department of Infectious Diseases and Immunology, Utrecht University, PO Box 80.165, 3508 TD, Utrecht, The Netherlands
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Kanobana K, Koets A, Bakker N, Ploeger HW, Vervelde L. T-cell mediated immune responses in calves primary-infected or re-infected with Cooperia oncophora: similar effector cells but different timing. Int J Parasitol 2003; 33:1503-14. [PMID: 14572513 DOI: 10.1016/s0020-7519(03)00211-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cooperia oncophora is the most prevalent intestinal nematode of cattle occurring in Western Europe. Primary infection with 100000 third stage infective larvae (L3) induces acquired immunity in a high proportion of the animals but there is little information on immunity against re-infection. In the current experiment, the contribution of the T-cell mediated immunity in protection against re-infection with C. oncophora was investigated in detail. Priming elicited long-lasting protective immunity that was evidenced by a significantly decreased worm burden and egg excretion in primed animals compared to challenge control animals. Lymphocyte proliferation tests with excretory/secretory products (ESP) of C. oncophora and with three distinct ESP fractions indicated an enhanced reactivity in primed animals and suggested that by fractionating of ESP we selected for proteins involved in protective immunity against re-infection with C. oncophora. Phenotypic analysis of T cell subsets at diverse anatomical locations revealed that the enhanced reactivity of lymphocytes from peripheral blood and lymph nodes of the infected animals coincided with a significantly increased frequency of CD4(+) cells at these locations but a deceased frequency of CD4(+) cells in the lamina propria. These findings were independent of the immune status of the animals but more pronounced in the primed animals than in the challenge control animals. In addition we demonstrated that primary and secondary infections with C. oncophora were associated with two waves of eosinophils and that the kinetics of this cell population differed as a result of priming. Based on the observed correlations we propose that the early increase of eosinophils is T cell independent and merely a consequence of inflammation in the parasitised gut. In contrast, the second wave of eosinophils depends upon CD4(+) cells and correlations with parasitological parameters at this time point support a role of eosinophils as effector cells against adult stages of C. oncophora.
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Affiliation(s)
- K Kanobana
- Department of Infectious Diseases and Immunology, Utrecht University, PO Box 80.165, 3508 TD, Utrecht, The Netherlands
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Abstract
Immunological memory responses to intracellular protozoa and extracellular helminths govern host resistance and susceptibility to reinfection. Humans and livestock living in parasitic disease endemic regions face continuous exposure from a very early age that often leads to asymptomatic chronic infection over their entire lifespan. Fundamental immunological studies suggest that the generation of T-cell memory is driven by tightly coordinated innate and adaptive cellular immune responses rapidly triggered following initial host infection. A key distinguishing feature of immune memory maintenance between the majority of parasitic diseases and most bacterial or viral diseases is long-term antigen persistence. Consequently, functional parasite immune memory is in a continuous, dynamic flux between activation and deactivation producing functional parasite killing or functional memory cell death. In this sense, T-cell immune memory can be regarded as "memory illusion." Furthermore, due to the finite capacity of memory lymphocytes to proliferate, continuous parasite antigen stimulation may exceed a threshold level at some point in the chronically infected host. This may result in suboptimal effector immune memory leading to host susceptibility to reinfection, or immune dysregulation yielding disease reactivation or immune pathology. The goal of this review is to highlight, through numerous examples, what is currently known about T-cell immune memory to parasites and to provide compelling hypotheses on the survival and maintenance of parasite "memory illusion." These novel concepts are discussed in the context of rationale parasite vaccine design strategies.
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Affiliation(s)
- David A Brake
- Veterinary Medicine Biologicals Development, Pfizer Animal Health Group, Pfizer, Inc., Groton, Connecticut 06340, USA.
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Gasbarre LC, Leighton EA, Sonstegard T. Role of the bovine immune system and genome in resistance to gastrointestinal nematodes. Vet Parasitol 2001; 98:51-64. [PMID: 11516579 DOI: 10.1016/s0304-4017(01)00423-x] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gastrointestinal nematode infections of cattle remain a constraint on the efficient raising of cattle on pasture throughout the world. Most of the common genera of parasites found in cattle stimulate an effective level of protective immunity in most animals within the herd after the animals have been on pasture for several months. In contrast, cattle remain susceptible to infection by Ostertagia for many months, and immunity that actually reduces the development of newly acquired larvae is usually not evident until the animals are more than 2 years old. This prolonged susceptibility to reinfection is a major reason that this parasite remains the most economically important GI nematode in temperate regions of the world. Although, animals remain susceptible to reinfection for a prolonged period of time, there are a number of manifestations of the immune response that result in an enhanced level of herd immunity. These include a delay in the development time of the parasites, an increase in the number of larvae that undergo an inhibition in development, morphological changes in the worms, stunting of newly acquired worms, and most importantly a reduction in the number of eggs produced by the female worms. The overall result of these manifestations of immunity is a reduction in parasite transmission within the cattle herd. The immune mechanisms responsible for these different types of functional immunity remain to be defined. In general, GI nematode infections in mammals elicit very strong Th2-like responses characterized by high levels of Interleukin 4 (IL4), high levels of IgG1 and IgE antibodies, and large numbers of mast cells. In cattle, the most extensively studied GI nematode, in regards to host immune responses, is Ostertagia ostertagi. In Ostertagia infections, antigens are presented to the host in the draining lymph nodes very soon after infection, and within the first 3-4 days of infection these cells have left the nodes, entered the peripheral circulation, and have homed to tissues immediately surrounding the parasite where they become established. The immune response seen in the abomasum is in many ways are similar to that seen other mammalian hosts, with high levels of expression of IL4 in the draining lymph nodes and in lymphocytes isolated from the mucosa. But unlike a number of other systems, lymphocyte populations taken from Ostertagia infected cattle seem to be up-regulated for a number of other cytokines, most notably Interferon (IFN, implying that in Ostertagia infections, the immune response elicit is not simply a stereotypic Th2 response. In addition, effector cell populations in the tissues surrounding the parasites, are not typical, inferring the Ostertagia has evolved means to suppress or evade protective immune mechanisms. Studies have also demonstrated that the number of nematode eggs/gram (EPG) in feces of pastured cattle is strongly influenced by host genetics and that the heritability of this trait is approximately 0.30. In addition, EPG values are not "normally" distributed and a small percentage of a herd is responsible for the majority of parasite transmission. This suggests that genetic management of a small percentage of the herd can considerably reduce overall parasite transmission. A selective breeding program has been initiated to identify the host genes controlling resistance/susceptibility to the parasites. The best indicator of the number of Cooperia infecting a host is the EPG value, while Ostertagia is best measured by serum pepsinogen levels, weight gain, and measures of anemia. Other phenotypic measures are either not significantly associated with parasite numbers or are very weakly correlated. In addition, calves can be separated into three types: (1) Type I which never demonstrates high EPG values, (2) Type II which shows rises in EPG values through the first 2 months on pasture which then fall and remain at levels associated with Type I calves, and (3) Type III calves which maintain high EPG levels. The approximate percentage of these calves is 25:50:25 respectively. Because these cattle are segregating for traits involved in resistance and susceptibility to GI nematodes, this resource population is being used to effectively detect the genomic locations of these Economic Trait Loci (ETL). For relational analysis between phenotype and genome location, over 80,000 genotypes have been generated by PCR amplification, and marker genotypes have been scored to produce inheritance data. The marker allele inheritance data is currently being statistically analyzed to detect patterns of co-segregation between allele haplotype and EPG phenotypes. Statistical power of this genome-wide scan has been strengthened by including genotypic data from the historic pedigree. In our herd, paternal half-sib families range from 5-13 progeny/sire, and extensive marker genotypes are available from ancestors of the population most of which are paternally descended from a single founding sire. Once ETL have been identified the next will be to refine ETL map resolution in attempt to discover the genes underlying disease phenotypes. Accurate identification of genes controlling resistance will offer the producer several alternatives for disease control. For a non-organic producer, the small percentage of susceptible animals can be targeted for drug administration. This approach would reduce both the cost of anthelmintics used and the odds for selection of drug resistant mutants, because the selective agent (drug) would not be applied over the entire parasite population. A second treatment option would be based on correcting a heritable immunologic condition. In this case, susceptible animals could be the targets for immunotherapy involving vaccines of immunomodulation. A final option would be genetic selection to remove susceptible animals from the herd. Producers with a high degree of risk for parasite-induced production losses, such as organic producers of producers in geographic areas with environmental conditions favorable to high rates of transmission would benefit the most from this strategy. In contrast, producers at low risk could take a more conservative approach and select against susceptibility when other factors were equal.
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Affiliation(s)
- L C Gasbarre
- Immunology and Disease Resistance Laboratory, ARS, USDA, Beltsville, MD 20705-5130, USA
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17
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Balic A, Bowles VM, Meeusen EN. Cellular profiles in the abomasal mucosa and lymph node during primary infection with Haemonchus contortus in sheep. Vet Immunol Immunopathol 2000; 75:109-20. [PMID: 10889303 DOI: 10.1016/s0165-2427(00)00189-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Cellular changes in the abomasal tissue and draining abomasal lymph nodes were examined after primary infection of lambs with Haemonchus contortus for 3, 5 or 27-36 days. Infection with H. contortus larvae resulted in a rapid and selective increase in the percentage of CD4(+) T-cells in the abomasal lymph node at 3 days post-infection (PI). By 5 days PI, the lymph node weight had increased two-fold; however, the percentage of lymphocyte populations in the abomasal lymph node resembled that seen in uninfected sheep. Lymph node weights remained at increased levels in the adult nematode infected sheep and down-regulation of B-cell surface markers (sIg and MHC Class II) was apparent in this group. Significant increases in the percentage of CD4(+) T-cells co-expressing MHC Class II, but not CD25, were observed in the larval infected groups except in adult nematode infected sheep. Increased numbers of eosinophils, CD4(+), gamma delta(+) T-cells and B-cells were found in the abomasal tissue by 5 days PI, but no further increases in these cell populations were observed in the adult nematode infected group. In contrast, the level of both lamina propria and intraepithelial mast cells observed in the abomasal mucosa was highest in the sheep carrying an adult nematode burden. These findings indicate that sheep are able to generate an early immune response to infection with H. contortus larvae, characterised by the activation of CD4 T-cells and B-cells in the draining lymph nodes and recruitment of eosinophils, CD4(+) and gamma delta-TCR,WC1(+) T-cells and B-cells in larval infected tissues. However, these changes do not seem to be maintained during infection with the adult parasite where increases in mast cell numbers dominate the local response, indicating that different parasite stages may induce distinct and possibly counteractive immune responses.
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Affiliation(s)
- A Balic
- Centre for Animal Biotechnology, School of Veterinary Science, The University of Melbourne, VIC. 3052, Parkville, Australia.
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18
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Balic A, Bowles VM, Meeusen EN. The immunobiology of gastrointestinal nematode infections in ruminants. ADVANCES IN PARASITOLOGY 2000; 45:181-241. [PMID: 10751941 DOI: 10.1016/s0065-308x(00)45005-0] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The major gastrointestinal nematode parasites of ruminants all belong to the Order Strongylida and the family Trichostrongyloidea. Despite this close evolutionary relationship, distinct differences exist in the microenvironmental niches occupied by the developmental stages of the various parasites, which may account for the variable susceptibility of the different parasite species to the immune effector mechanisms generated by the host. In addition, different manifestations of resistance have been observed against the adult and larval stages of the same parasite species, and even against the same parasite stage. In particular, both rapid and delayed rejection of infective larval stages of gastrointestinal nematode parasites has been documented. This review will give an overview of the various manifestations of resistance to gastrointestinal nematode parasites of ruminants, as well as the immune mechanisms and antigens associated with the generation of immunity by the ruminant hosts to these parasites. In addition, a working model is provided aimed at reconciling most of the present knowledge on the different immune responses generated during infection with the various parasite rejection profiles. Extrapolation of these results to field conditions will need to take into account the variability imposed by seasonal changes and management practices, as well as the individual variability in immune responsiveness present in outbred animal populations.
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Affiliation(s)
- A Balic
- Centre for Animal Biotechnology, School of Veterinary Science, University of Melbourne, Victoria, Australia
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19
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De Marez T, Liddell S, Dubey JP, Jenkins MC, Gasbarre L. Oral infection of calves with Neospora caninum oocysts from dogs: humoral and cellular immune responses. Int J Parasitol 1999; 29:1647-57. [PMID: 10608451 DOI: 10.1016/s0020-7519(99)00154-x] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Neospora caninum has been identified as a major cause of abortion in cattle in a number of countries throughout the world. Until the recent demonstration that dogs can serve as a definitive host of this parasite, it was not possible to study the infection in cattle orally exposed to oocysts. The aim of this study was to investigate the potential of N. caninum oocysts to infect calves, and to define initial immune responses that arise after oral infection. Seven calves were fed approximately 10(4)-10(5) N. caninum oocysts, three calves served as uninfected controls. Before infection, all calves were serologically negative for anti-Neospora antibodies and the calves were non-reactive to Neospora antigen in an in vitro lymphocyte proliferation assay. Peripheral blood lymphocytes from inoculated calves were able to mount in vitro proliferative responses to crude N. caninum antigen extract as early as 1 week p.i. Within 2 and 4 weeks p.i., Neospora-specific IgG1 and IgG2 antibodies were detected by IFAT and ELISA in serum from infected calves but not from sham-infected calves. The continued presence of reactive cells in the blood, spleen and mesenteric, inguinal, bronchial lymph nodes was seen as late as 2.5 months p.i., and parasite DNA was detected in the brain and spinal cord of the infected animals by PCR, indicating that the cattle were infected by oral inoculation of N. caninum oocysts collected from dogs, and that the animals were systematically sensitised by parasite antigen.
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Affiliation(s)
- T De Marez
- US Department of Agriculture, Agricultural Research Service, Livestock and Poultry Sciences Institute, Immunology and Disease Resistance Laboratory, Beltsville, MD 20705-2350, USA.
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20
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Almería S, Canals A, Gómez-Muñoz MT, Zarlenga DS, Gasbarre LC. Characterization of protective immune responses in local lymphoid tissues after drug-attenuated infections with Ostertagia ostertagi in calves. Vet Parasitol 1998; 80:53-64. [PMID: 9877071 DOI: 10.1016/s0304-4017(98)00185-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In the present study, cell-surface markers and cytokine gene expression of lymphocytes from the local lymph nodes were studied 9 days after primary infection with Ostertagia ostertagi in previously naive calves or in calves previously immunized with multiple, chemically attenuated infections. Changes in lymphocyte populations were assessed by flow cytometry utilizing monoclonal antibodies specific for bovine cell-surface markers. Changes observed in the percentages of lymphoid populations after challenge were similar in animals immunized by either three or five drug-attenuated infections. In both immunized groups, the CD4+/CD8+ ratio was significantly higher than in naive animals after challenge infections. In addition, both immunized groups showed significantly lower levels of Ig-bearing cells upon experimental challenge when compared to animals with a primary experimental infection. No differences were observed in the number of gammadelta or interleukin 2 receptor (IL-2R) positive cells. The levels of mRNA for IL-4, IL-10, IL-15, IFN-gamma and TGF-beta1 were examined by competitive RT-PCR. After challenge, the levels of these cytokines were lower in animals immunized by five drug-attenuated infections, and in the case of IL-4 and TGF-beta1, these differences were statistically significant. These results indicate that animals exhibiting protection from reinfection with O. ostertagi do not show a shift to higher percentages of Ig+ cells characteristic of a primary infection. In addition, protected animals appear to show a decreased IL4 and TGF-beta1 response upon challenge when compared to non-immune animals.
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Affiliation(s)
- S Almería
- USDA, ARS, LPSI, Immunology and Disease Resistance Laboratory, Beltsville, MD 20705, USA
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21
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Gasbarre LC. Effects of gastrointestinal nematode infection on the ruminant immune system. Vet Parasitol 1997; 72:327-37; discussion 337-43. [PMID: 9460205 DOI: 10.1016/s0304-4017(97)00104-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Gastrointestinal (GI) nematodes of ruminants evoke a wide variety of immune responses in their hosts. In terms of specific immune responses directed against parasite antigens, the resulting immune responses may vary from those that give strong protection from reinfection after a relatively light exposure (e.g. Oesophagostomum radiatum) to responses that are very weak and delayed in their onset (e.g. Ostertagia ostertagi). The nature of these protective immune responses has been covered in another section of the workshop and the purpose of this section will be to explore the nature of changes that occur in the immune system of infected animals and to discuss the effect of GI nematode infections upon the overall immunoresponsiveness of the host. The discussion will focus primarily on Ostertagia ostertagi because this parasite has received the most attention in published studies. The interaction of Ostertagia and the host immune system presents what appears to be an interesting contradiction. Protective immunity directed against the parasite is slow to arise and when compared to some of the other GI nematodes, is relatively weak. Although responses that reduce egg output in the feces or increase the number of larvae undergoing inhibition may occur after a relatively brief exposure (3-4 months), immune responses which reduce the number of parasites that can establish in the host are not evident until the animal's second year. Additionally, even older animals that have spent several seasons on infected pastures will have low numbers of Ostertagia in their abomasa, indicating that sterilizing immune responses against the parasite are uncommon. In spite of this apparent lack of specific protective immune responses, infections with Ostertagia induce profound changes in the host immune system. These changes include a tremendous expansion of both the number of lymphocytes in the local lymph nodes and the number of lymphoid cells in the mucosa of the abomasum. This expansion in cell numbers involves a shift away from a predominant classic T cell population (CD2 and CD3 positive), to a population where T cell percentages are decreased and B cells (immunoglobulin-bearing) and gamma-delta cells are increased. At the same time the expression of messenger RNAs for T cell cytokines (IL2, IL4, IL10 and gamma-interferon) is changed to that of increased expression of IL4 and IL10 and decreased expression of IL2 and perhaps of gamma-interferon. The reasons for these changes remain to be elucidated, but it is evident that the lack of protective immune responses is not the result of a poor exposure of the host to parasite products, or to the stomach being an immunoprivileged site. In fact, a superficial look at the responses elicited indicates that Ostertagia induces responses (the so-called TH2 mediated responses) that are widely considered to be the type of responses necessary for protection against GI nematodes. There are many factors that could lead to this apparent lack of immunity in the face of a strong stimulation of immune responses including: (1) the elicitation of suboptimal responses; (2) the failure of the abomasum to function as an efficient effector organ; (3) active evasion of the functional immune response by the parasite; and (4) that these classic responses are not protective in this particular ruminant-parasite system and that novel protective mechanisms may be required. The strong stimulation of the host gut immune system by Ostertagia and perhaps by other GI nematode infections, raises questions about the potential effects of such infections on the overall well-being of the host. A number of authors have indicated that Ostertagia infections may diminish the host's ability to mount subsequent immune responses to antigenic challenges such as vaccination against other infectious organisms. In addition, recent studies have indicated that infections with GI nematodes may result in increased circulatory levels of stress-related hormo
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Affiliation(s)
- L C Gasbarre
- Immunology and Disease Resistance Laboratory, LPSI, ARS, USDA, Beltsville, MD 20705-2350, USA.
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22
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Canals A, Zarlenga DS, Almeria S, Gasbarre LC. Cytokine profile induced by a primary infection with Ostertagia ostertagi in cattle. Vet Immunol Immunopathol 1997; 58:63-75. [PMID: 9343340 DOI: 10.1016/s0165-2427(96)05775-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Changes that occur in the local draining lymph nodes including, changes in cell surface markers and cytokine gene expression were studied over the first 4 weeks of a primary, Ostertagia ostertagi infection of the abomasum. Cells recovered from the abomasal lymph nodes (ABLN) after infection showed a decrease in the percentage of CD3+ cells, and an increase in the percentage of IgM+ cells and cells bearing the TcR1 marker. These changes were coincident with an increase in the proportion of activated cells (II-2R). Analysis of mitogen-stimulated ABLN cells by RNase protection assay (RPA) showed a dramatic reduction in IL-2 and IFN-gamma transcription after infection. In addition, analysis of unstimulated ABLN cells by competitive RT-PCR showed a similar decrease in demonstrable levels of IL-2 mRNA, but IL-10, IL-4 and IFN-gamma mRNA levels were elevated.
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Affiliation(s)
- A Canals
- USDA, ARS, LPSI, Immunology and Disease Resistance Laboratory, Beltsville, MD 20705, USA
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23
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Canals A, Gasbarre LC, Boyd PC, Almeria S, Zarlenga DS. Cloning and expression of bovine interleukin-15: analysis and modulation of transcription by exogenous stimulation. J Interferon Cytokine Res 1997; 17:473-80. [PMID: 9282828 DOI: 10.1089/jir.1997.17.473] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The bovine interleukin-15 (IL-15) sequence was cloned from abomasal lymph node mRNA by enzymatic amplification of cDNA using human primers proximal to and including the translation start and stop sites. The open reading frame is 486 base pairs in length, and the proposed protein sequence shows 78.4% and 73.5% similarity with that predicted for the human and mouse sequences, respectively. Expressed and purified recombinant bovine IL-15 in the absence of the 48-amino acid leader sequence stimulated the proliferation of bovine lymphoblast cells at least 12-fold over background at maximum concentration levels. Competitive reverse transcriptase-polymerase chain reaction analysis showed constitutive levels of IL-15 mRNA within a broad range of tissues and cell types. Lipopolysaccharide addition to adherent lymph node populations caused moderate increases in IL-15 transcription, whereas the addition of phorbol 12-myristate 13-acetate and calcium ionophore failed to induce gene expression for this cytokine. Transcription of IL-15 was also downregulated in the presence of low concentrations of human recombinant interleukin-2.
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Affiliation(s)
- A Canals
- U.S. Department of Agriculture, Agricultural Research Service, Immunology and Disease Resistance Lab, Beltsville, MD 20705, USA
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24
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Almería S, Canals A, Zarlenga DS, Gasbarre LC. Isolation and phenotypic characterization of abomasal mucosal lymphocytes in the course of a primary Ostertagia ostertagi infection in calves. Vet Immunol Immunopathol 1997; 57:87-98. [PMID: 9239841 DOI: 10.1016/s0165-2427(96)05776-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Isolation and characterization of surface marker phenotypes of abomasal intraepithelial (IEL), lamina propria (LPL) and abomasal lymph node lymphocytes (ABLN) from uninfected calves were conducted, and the dynamics of change in these populations during the course of a primary Ostertagia ostertagi infection were defined. To obtain viable IEL and LPL from the abomasal mucosa of cattle, a modified isolation method was developed. The phenotypic characterization of abomasal lymphocytes was accomplished by indirect immunofluorescence staining. In uninfected animals, numbers of T cells exceeded the number of immunoglobulin-bearing cells in IEL, LPL and ABLN. The predominant T cell type in IEL and LPL was CD8+ cells, while the CD4+ T cell predominated in ABLN. Levels of activated cells and T cell receptor-1 gamma delta T cells were higher in IEL and LPL compared to ABLN. Within 3 weeks of infection, the number of lymphocytes recovered from the abomasal lamina propira and the mass of the ABLN was dramatically increased when compared to uninfected animals. Laser flow cytometric analysis demonstrated increased levels of immunoglobulin-bearing cells, gamma delta T cells, and activated T cells in IEL, LPL and ABLN in the infected animals. The greatest changes in LPL and ABLN took place during the first days of infection, and these changes were apparent throughout the 28 days covered by the experiment.
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Affiliation(s)
- S Almería
- USDA, ARS, LPSI, Immunology and Disease Resistance Laboratory, Beltsville, MD 20705, USA
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