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71.
S Naik N Bouladoux C Wilhelm MJ Molloy R Salcedo W Kastenmuller C Deming M Quinones L Koo S Conlan S Spencer JA Hall A Dzutsev H Kong DJ Campbell G Trinchieri JA Segre Y Belkaid 《Science (New York, N.Y.)》2012,337(6098):1115-1119
Intestinal commensal bacteria induce protective and regulatory responses that maintain host-microbial mutualism. However, the contribution of tissue-resident commensals to immunity and inflammation at other barrier sites has not been addressed. We found that in mice, the skin microbiota have an autonomous role in controlling the local inflammatory milieu and tuning resident T lymphocyte function. Protective immunity to a cutaneous pathogen was found to be critically dependent on the skin microbiota but not the gut microbiota. Furthermore, skin commensals tuned the function of local T cells in a manner dependent on signaling downstream of the interleukin-1 receptor. These findings underscore the importance of the microbiota as a distinctive feature of tissue compartmentalization, and provide insight into mechanisms of immune system regulation by resident commensal niches in health and disease. 相似文献
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73.
Selhorst T Freuling CM Blicke J Vos A Larres G Zimmer K Fröhlich T Bätza HJ Müller TF 《Berliner und Münchener tier?rztliche Wochenschrift》2012,125(5-6):191-196
In 2005, the final phase of terrestrial rabies eradication in Germany was put at risk by a severe setback due to re-introduction of the disease in Rhineland-Palatinate from neighbouring Hesse after seven years of absence. The rapid westward spread of the disease prompted veterinary authorities to react swiftly and apply a new yet unproven vaccination strategy to rapidly increase herd immunity in an almost unprotected fox population to stop the epidemic. The cornerstones of this emergency oral rabies vaccination strategy, i. e. vaccination intervals, identification of high risk spots, real time epidemiological assessment, capable to eliminate rabies within 13 months after incursion are described here. This strategy may be used as a template to tackle similar emergency situations in Europe in the future. 相似文献
74.
CD23, also called FcεRII, is the low-affinity receptor for IgE and has first been described as a major receptor regulating IgE responses. In addition, CD23 also binds to CD21, integrins and MHC class II molecules and thus has a much wider functional role in immune regulation ranging from involvement in antigen-presentation to multiple cytokine-like functions of soluble CD23. The role of CD23 during immune responses of the horse is less well understood. Here, we expressed equine CD23 in mammalian cells using a novel IL-4 expression system. Expression resulted in high yield of recombinant IL-4/CD23 fusion protein which was purified and used for the generation of monoclonal antibodies (mAbs) to equine CD23. Seven anti-CD23 mAbs were further characterized. The expression of the low-affinity IgE receptor on equine peripheral blood mononuclear cells was analyzed by flow cytometric analysis. Cell surface staining showed that CD23 is mainly expressed by a subpopulation of equine B-cells. Only a very few equine T-cells or monocytes expressed CD23. CD23(+) B-cells were either IgM(+) or IgG1(+) cells. All CD23(+) cells were also positive for cell surface IgE staining suggesting in vivo IgE binding by the receptor. Two of the CD23 mAbs detected either the complete extracellular region of CD23 or a 22kDa cleavage product of CD23 by Western blotting. The new anti-CD23 mAbs provide valuable reagents to further analyze the roles of CD23 during immune responses of the horse in health and disease. 相似文献
75.
Pridgeon JW Klesius PH Mu X Yancey RJ Kievit MS Dominowski PJ 《Veterinary immunology and immunopathology》2012,145(1-2):179-190
The potential of using a QCDCR (quilA:cholesterol:dimethyl dioctadecyl ammonium bromide:carbopol:R1005 glycolipid) formulated CpG oligodeoxynucleotide (ODN), ODN 2007, to confer protection in Nile tilapia against Streptococcus iniae infection was evaluated in this study. At two days post treatment, QCDCR formulated ODN 2007 elicited significant (P<0.05) protection to Nile tilapia, with relative percent survival of 63% compared to fish treated by QCDCR alone. To understand the molecular mechanisms involved in the protective immunity elicited by ODN 2007, suppression subtractive cDNA hybridization technique was used to identify upregulated genes induced by ODN 2007. A total of 69 expressed sequence tags (ESTs) were identified from the subtractive cDNA library. Quantitative PCR revealed that 44 ESTs were significantly (P<0.05) upregulated by ODN 2007, including 29 highly (>10-fold) and 15 moderately (<10-fold) upregulated ESTs. Of all ESTs, putative peroxisomal sarcosine oxidase was upregulated the highest. The 69 ESTs only included six genes that had putative functions related to immunity, of which only two (putative glutaredoxin-1 and carboxypeptidase N catalytic chain) were confirmed to be significantly upregulated. Our results suggest that the protection elicited by ODN 2007 is mainly through innate immune responses directly or indirectly related to immunity. 相似文献
76.
77.
Neospora caninum is an apicomplexan protozoan parasite that is one of the most important infectious causes of abortion in both dairy and beef cattle in many countries. The objectives of this longitudinal study were to determine the prevalence, rates of vertical and horizontal transmission of N. caninum and hazard for culling of N. caninum-seropositive animals in three Brazilian dairy herds. Blood samples from all animals were collected nine times at each of the three farms over a two-year period. Serum was tested for antibodies against N. caninum using the indirect fluorescent antibody test with a cutoff value of 1:100. The percentage of N. caninum-positive samples at each sampling time ranged at Farm I from 3.32% to 11.71%, at Farm II from 3.90% to 22.06% and at Farm III from 3.90% to 22.06%. The number of positive serological reactions varied in relation to the number of repeated samples taken from individual animals at each farm. In all herds, there was a high degree (P<0.05) of association between the N. caninum serological status of dams and daughters. The seropositive conversion rate was estimated as 0.37%, 3.00% and 6.94% per 100 cow-years at Farms I, II and III, respectively. The seronegative conversion rate was estimated as 31.58% and 11.11% per 100 cow-years at Farms I and III, respectively. In all herds, there was no difference (P>0.05) in the culling rate between the cattle that were seropositive cattle and seronegative for N. caninum infection. The results from this study confirm the importance of vertical transmission in the epidemiology of N. caninum. Although a few positive seroconversions indicated horizontal transmission, it does not appear to be the major route of infection for N. caninum. 相似文献
78.
Julia B. Montgomery Jeffrey J. Wichtel Maureen G. Wichtel Mary A. McNiven J.T. McClure Fred Markham David W. Horohov 《Journal of Equine Veterinary Science》2012
The effect of organic and inorganic sources of selenium (Se) on measures of Se status of mares and their foals, Se concentrations of colostrum and milk, and indices of immune function of foals was studied. Twenty late-gestation Standardbred mares were randomly assigned to one of two groups. All mares received an identical balanced ration, except for the source of supplementary Se: one group received organic Se (Se yeast) and the other group received inorganic Se (sodium selenite), fed to deliver 0.3 mg/kg supplementary Se based on total ration dry matter. Mares received the experimental diet from 2 months before estimated due date until 1 month after foaling. Source of Se did not affect Se concentrations in maternal plasma, red blood cells, colostrum, or milk. At 1 month of age, foals from mares fed organic Se had higher red blood cell Se concentration than foals from mares fed inorganic Se (P < .05). Measures of immunity included serum immunoglobulin G concentration, lymphocyte proliferation in response to concanavalin A, and relative cytokine gene expression of stimulated lymphocytes (interferon gamma [IFNγ], interleukin [IL]-2, IL-5, IL-10, tumor necrosis factor alpha [TNFα]) and neutrophils (IL-1, IL-6, IL-8, IL-12, TNFα). Relative gene expression of IL-2, TNFα, and IFNγ by foal lymphocytes was associated with the source of Se supplementation provided to the mares. We conclude that the source of dietary Se provided to mares may influence the immune function of foals at 1 month of age through changes in relative gene expression of certain lymphocyte cytokines. 相似文献
79.
McCally RE Kim SE Bacon NJ Winter MD Cords AA Conway JA 《Journal of the American Animal Hospital Association》2012,48(3):198-202
A 2 yr old dog presented for dysphagia and coughing secondary to a 4 cm × 4 cm turgid subepiglottic mass. Cervical radiographs, an esophagram, and computed tomography confirmed the presence of a cystic mass that was not intimately associated with any surrounding structures. An incisional biopsy confirmed the cystic nature of the mass and helped to rule out a malignancy. A marginal surgical excision was performed via a ventral approach. Histopathology of the mass was consistent with a thyroglossal duct cyst. This is the first report of a thyroglossal duct cyst in this location in a dog. There was no recurrence of clinical signs 14 mo after surgery. 相似文献
80.
A spinal cord lesion localised caudal to the L6 spinal segment was diagnosed in a 2-year-old female spayed domestic longhair cat with acute onset paraparesis. Magnetic resonance imaging findings were consistent with an acute, non-compressive nucleus pulposus extrusion of the L5-L6 intervertebral disc. The cat was successfully managed with supportive care, including cage confinement. 相似文献