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1.
Canine distemper virus (CDV) infection induces multifocal demyelination in the central nervous system (CNS). It is thought that the resident macrophages of the CNS, the microglia, as well as invading monocytes associated with the inflammatory reaction may play a central role in the demyelinating process. To evaluate changes in peripheral monocytes in CDV infection their immunophenotype was characterized by flow cytometry during the course of an experimental CDV infection in dogs. The highest number of CDV-infected monocytes was found in dogs developing demyelinating lesions. In CD18, CD45, CD44, and CD14 neither up- nor down-regulation was observed. Marked up-regulation occurred in a number of surface molecules including CD1c, B7-1 and B7-2, MHC I, and CD11b. Peak expression was found at 4-5 weeks post-infection (PI), regardless of clinical outcome. All these molecules play an important role in the host's immune response, notably antigen presentation and cell adhesion. These results demonstrate that CDV infection in vivo may enhance several macrophage functions. This could lead to more effective clearance of the virus but may also increase demyelination through a bystander effect in animals that accumulated significant amounts of CDV in the CNS.  相似文献   

2.
Immunohistochemistry was used to examine the immuno-pathological changes and the extent of neuronal damage caused by either viable or dead Taenia solium cysticerci during porcine neurocysticercosis. Thirty pig brains with cerebral cysticercosis and 5 brains from T. solium free pigs were used in this study. Results revealed extensive astrogliosis, neuronal and mostly axonal damage in both early (grade I) and late (grades III and V) lesions as evidenced by an increased expression of glial fibrillary acidic protein (GFAP) and neurofilament protein (NFP). In many late lesions, astrocyte end-feet formed glial scars that surrounded the dead parasite. Rapid angiogenesis resulted in blood vessels lacking astrocyte end-feet suggesting loss of blood–brain barrier (BBB) hence allowing an influx of peripheral blood immune cells such as eosinophils, macrophages, CD3+ T cells, B lymphocytes and plasma cells into lesions. This study showed that porcine NCC was associated with severe nervous tissue damage, the host response of which is a collaborative effort between the local and peripheral immune responses comparable to that observed in human NCC. Results further implied that porcine NCC could be a useful model for understanding the course of NCC in human as well as provide useful information for therapeutic and/or immune strategies.  相似文献   

3.
猪圆环病毒2型免疫抑制机理研究进展   总被引：4，自引：0，他引：4  
猪圆环病毒2型(PCV-2)致病的一个主要原因是使感染的个体产生免疫抑制,感染猪体免疫细胞受到不同程度的损伤.PCV-2可以在单核细胞、巨噬细胞等抗原递呈细胞中存在,影响这些细胞对于抗原的递呈.PCV-2也可在T淋巴细胞及B淋巴细胞中增殖,引起机体体液免疫及细胞免疫反应能力的下降.调节免疫的各种细胞因子在感染PCV-2后也有一定程度的改变,PCV-2感染可引起IL-10分泌的增加,PCV-2与猪天然干扰素分泌细胞相互作用,可使这些细胞分泌干扰素的能力下降.PCV-2造成免疫抑制也与病毒ORF3分泌的功能蛋白有一定的关系,ORF3可诱导免疫细胞凋亡,主要是激活caspase-8途径而不是caspase-9途径.  相似文献   

4.
The influence of an attenuated classical swine fever virus C strain vaccine and a subunit E2 vaccine against classical swine fever on the peripheral blood leucocyte proportion and phenotypic expression in 12-week-old pigs was studied. The C strain was amplified in minipig kidney cell culture and final product contained 10(4 +/- 0.15) TCID50/ml, while the subunit vaccine contained 32 microg per dose of gp E2. Haematological findings showed that the vaccines did not cause leucopenia or lymphocytopenia and the number of neutrophils and eosinophils during the observation period was within physiological range. The results of the proportion of CD4a+, CD5a+, CD8a+, wCD21+, CD45RA+, CD45RC+ , non-T non-B, SWC3a+ and CD11b+ cells were gained by single-colour flow cytometry. At the end of the trial a significantly increase of percentage of CD4+, CD5a+, CD8+, wCD21+ cells has been found in pigs that received the subunit vaccine and the percentage of CD4+, CD5a+, CD8+, CD45RA+ and CD45RC+ cells was higher in pigs that received the attenuated vaccine. Twenty-eight days after vaccination the percentage of CD4+, CD45RA+ and CD45RC+ was significantly higher in pigs vaccinated with the C strain than in pigs vaccinated with the subunit vaccine. In contrary, the percentage of the wCD21- cells was higher in pigs that received the subunit vaccine. Statistically higher values of SWC3a+ and lower values of CD11b+ cells was observed in pigs that received the attenuated vaccine than in pigs vaccinated with the subunit vaccine. Taken altogether, our results showed that the subunit vaccine produced a better stimulation of B cells and CD11b+ monocytes/macrophages /granulocytes/NK cells, whereas the attenuated vaccine induced a higher response of Th cells, naive/memory cells and macrophages/neutrophils. Thus, both vaccines were able to influence the porcine immune system, by activating different subsets of the immune effector/accessory cells.  相似文献   

5.
Despite accumulating knowledge of porcine macrophages and dendritic cells (DCs) from in vitro studies, information regarding monocytes/macrophages and DCs in lymphoid tissues of enteric pathogen-infected neonatal animals in vivo is limited. In this study we evaluated the influence of commensal bacterial [two strains of lactic acid bacteria (LAB), Lactobacillus acidophilus and L. reuteri] colonization and rotavirus infection on distribution and frequencies of monocytes/macrophages and conventional DCs (cDCs) in ileum, spleen and blood. Gnotobiotic pigs were inoculated with LAB and virulent Wa strain human rotavirus (HRV) (LAB+HRV+), HRV only (LAB-HRV+), LAB only (LAB+HRV-) or mock (LAB-HRV-). The cDCs were characterized as SWC3(+)CD11R1(+), whereas monocytes/macrophages were identified as SWC3(+)CD11R1(-) by flow cytometry in the gnotobiotic pigs at 10 days of age. Infection with HRV alone activated/recruited significantly more monocytes/macrophages to the intestine than LAB colonization and 56% versus 28% of these cells expressed CD14. Colonization with LAB alone also significantly increased the frequencies of monocytes/macrophages and cDCs and the CD14 expression on monocytes/macrophages in ileum and spleen compared to the controls. LAB colonization plus HRV infection significantly reduced macrophage and cDC frequencies in spleen compared to LAB colonization or HRV infection alone, suggesting that LAB colonization down-regulated HRV- infection-induced monocyte/macrophage activation/recruitment at the systemic lymphoid tissue. These results illustrated the distribution of porcine monocytes/macrophages and cDCs and the frequencies of CD14 expression on these cells in intestinal and systemic lymphoid tissues in the early stage of immune responses to intestinal colonization by LAB versus infection by an enteric pathogen HRV and will facilitate further in vivo studies on functional characterization of these immune cells in neonates.  相似文献   

6.
This study describes the immunohistochemical and histochemical phenotypes of inflammatory cells in sheep lungs infected with lungworms. A total of 20 naturally infected sheep lungs were used. Protostrongylus spp., Muellerius capillaris, Neostrongylus linearis, and Cystocaulus ocreatus were the chief organisms determined from such lesions, which were of a chronic nature. All the lungs had many developmental stages of the parasites and a similar inflammatory response, which included numerous mast cells, eosinophils, T cells, B cells, dendritic cells, and macrophages. In the bronchial and interstitial tissues, the inflammatory cells were dominated by MHCII, CD1, CD4, CD5, CD14, CD21, IgM, and CD172a positive cells, whereas CD2 and WC1 positive cells were detected less. The data provided additional evidence that subsets of inflammatory cells were included within ovine lungs infected with lungworms; however, understanding the entire immune-response process and development of resistance to lungworms in sheep remain to be clearly elucidated.  相似文献   

7.
Pathology of the colon in pigs infected with Trichuris suis and fed an inulin and a non-inulin containing diet was studied to investigate the inflammatory response induced and the influence of inulin on this. Twenty-nine pigs were allocated into four groups (N-7, I-7, N-9 and N/I-9). Groups N-7, N-9 and N/I-9 were given a diet with non-fermentable carbohydrates, and group I-7 was fed a diet including fermentable carbohydrates (inulin). After 2 weeks, all pigs were inoculated with 2000 T. suis eggs. Seven weeks post-infection (p.i.), groups N-7 and I-7 were killed and group N/I-9 changed to inulin diet to study the influence of inulin on already established T. suis. Nine weeks p.i., groups N-9 and N/I-9 were killed. Trichuris suis were collected from the colon for enumeration. Tissues from the colon of each pig were taken for histological and immunohistochemical quantitative and semi-quantitative evaluations of heterophils, eosinophils, mast cells, IgA(+), IgG(+), IgM(+) and CD3(+) cells. The findings were compared with tissues from seven uninfected pigs of the same age. Pigs fed inulin had significantly fewer worms compared with pigs on the non-fermentable carbohydrate diet. The number of inflammatory cells in the colonic mucosa was increased in all T. suis-infected pigs compared with uninfected controls. The numbers of eosinophils, mast cells, IgA(+), IgG(+) and CD3(+) cells were significantly lower in pigs fed inulin than pigs fed non-fermentable carbohydrate. Whether this is a direct effect of inulin or a secondary effect due to the lower parasitic burden in inulin fed pigs is not known.  相似文献   

8.
The immune response of 'Yugoslav meat breed' pigs inoculated with low doses of Trichinella spiralis muscle larvae was followed over two to nine weeks of primary infection, by analysing changes in peripheral blood mononuclear cell subsets, the development of a humoral antibody response and muscle larvae burden. During the course of the infection, infected animals showed a persistent elevation of both CD4+ and CD8+ T cell subsets from days 15 to 60 after the parasite exposure. During this time, the number of peripheral blood mononuclear cells expressing major histocompatibility complex class II antigens was also increased, while no significant differences were found in the number of circulating monocytes/macrophages and B cells over time. Humoral antibody responses to muscle larvae excretory-secretory products were evident as early as 41 days after infection, while the muscle larvae were recovered as early as 27 days after infection. The increased levels of CD4+ and CD8+ T cell subsets, as well as cells expressing major histocompatibility complex class II antigens in pigs exposed to T spiralis, may be indicative of some considerable alterations in cell subsets that are involved in the regulation of the swine immune response to this parasite.  相似文献   

9.
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10.
The immunophenotype of tumor cells and inflammatory infiltrate associated with cutaneous melanocytic lesions (29 melanocytomas, two malignant melanomas, and 23 residual lesions) from 54 adult Iberian and Iberian x Duroc pigs were examined using a panel of nine antibodies. All neoplastic cells were vimentin+, cytokeratin-, and alpha-1-antitrypsin- and the majority were S100+, whereas all pigmented macrophages were vimentin+, cytokeratin-, and S100- and most expressed alpha-1-antitrypsin. Regressing tumors were characterized by zones with low density of neoplastic cells accompanied by heavy infiltration of CD3+ T lymphocytes, whereas zones with high density of neoplastic cells showed very low numbers of CD3+ T lymphocytes. The infiltrate of CD79a+ B cells and IgG, IgM, and IgA plasma cells was low. The majority of lymphocytes of the peri- and intratumoral infiltrate were major histocompatibility complex class II+, but neoplastic cells did not express class II antigen. The 17 residual lesions examined were composed of macrophages containing abundant melanin pigment and low to moderate numbers of CD3+ T lymphocytes. The results of the present study suggest that the local cellular immune response plays a crucial role in the host response that induces regression of cutaneous melanomas and melanocytomas of the Iberian and crossbred Iberian x Duroc pigs.  相似文献   

11.
Eight colostrum-deprived calves aged 8-12 weeks were inoculated intranasally with a non-cytopathic strain of bovine viral diarrhoea virus (BVDV) genotype-1 and the effects on the hepatic immune response were studied. Two calves were sacrificed at each of 3, 6, 9 and 14 days post-inoculation (dpi) and two uninoculated animals were used as negative controls. BVDV was detected in hepatic macrophages and monocytes from 3 to 14dpi and in Küpffer cells (KCs) from 6 to 14dpi. Increases in the numbers of MAC387(+) KCs and monocytes, but not interstitial macrophages, differentiated by morphological features, were evident in the liver following inoculation with BVDV. There was a substantial increase in the number of monocytes positive for tumour necrosis factor (TNF)-α, but only small increases in the numbers of TNF-α(+) KCs and interstitial macrophages and interleukin (IL)-6(+) monocytes, KCs and interstitial macrophages. There was an increase in the number of interstitial CD3(+) T lymphocytes in the liver, but no substantial changes in the numbers of circulating CD3(+) T lymphocytes, interstitial or circulating CD4(+) or CD8(+) T lymphocytes, or CD79αcy(+) B lymphocytes. Serum haptoglobin and serum amyloid A increased transiently at 12dpi. Upregulation of some pro-inflammatory cytokines by hepatic macrophages is evident in subclinical acute BVDV type 1 infection in calves.  相似文献   

12.
Expression of programmed cell death receptor ligand 1 (PD‐L1) on tumor cells has been associated with immune escape in human and murine cancers, but little is known regarding the immune regulation of PD‐L1 expression by tumor cells and tumor‐infiltrating macrophages in dogs. Therefore, 14 canine tumor cell lines, as well as primary cultures of canine monocytes and macrophages, were evaluated for constitutive PD‐L1 expression and for responsiveness to immune stimuli. We found that PD‐L1 was expressed constitutively on all canine tumor cell lines evaluated, although the levels of basal expression were very variable. Significant upregulation of PD‐L1 expression by all tumor cell lines was observed following IFN‐γ exposure and by exposure to a TLR3 ligand. Canine monocytes and monocyte‐derived macrophages did not express PD‐L1 constitutively, but did significantly upregulate expression following treatment with IFN‐γ. These findings suggest that most canine tumors express PD‐L1 constitutively and that both innate and adaptive immune stimuli can further upregulate PD‐L1 expression. Therefore the upregulation of PD‐L1 expression by tumor cells and by tumor‐infiltrating macrophages in response to cytokines such as IFN‐γ may represent an important mechanism of tumor‐mediated T‐cell suppression in dogs as well as in humans.  相似文献   

13.
The aim of this study was to investigate development over time of the surface expression of CD44 on macrophages during an inflammatory response of bovine mammary gland. Intramammary instillation of muramyl dipeptide (MDP) and lipopolysaccharide (LPS) resulted in a significant increase in the total count of CD44+ non-vacuolised macrophages (NMAC) after 24 h. During resolution of the inflammatory response, there was observed a gradual decrease in the total count CD44+ NMAC. The lower total count and proportion of CD44 + vacuolised macrophages (VMAC) was observed as the effect of MDP and LPS at 24 h after induction (P < 0.01). During resolution, the total count and proportion of CD44 + VMAC increased. We have demonstrated CD44 receptor is expressed during the inflammatory response caused by LPS and MDP and the effect of these components on CD44 expression was particularly evident during initiation of the inflammatory response. High expression of CD44 in resolution of inflammatory response may relate to macrophages´ involvement in the processes leading to restitution of injured tissues.  相似文献   

14.
TLRs, Siglecs and CD163 are cell surface receptors that play an important role in immune response and sepsis. The objective of this study was to assess changes in the expression levels of several of these receptors (TLR2, TLR4, CD163, Siglec-1, Siglec-3, Siglec-5 and Siglec-10) on the surface of peripheral blood mononuclear cells from pigs with sepsis caused by Haemophilus parasuis. Flow cytometry was employed to analyze samples from an experimental infection and from cell cultures. A significant increase in CD163, TLR2 and Siglec-3 expression during infection was seen. However, in vitro exposure of peripheral blood monocytes to bacteria or sera from infected pigs did not increase the expression of these receptors. These changes may be due to recruitment of monocytes into the blood compartment in response to H. parasuis-induced sepsis.  相似文献   

15.
Feline infectious peritonitis (FIP) is a fatal, coronavirus (CoV)-induced systemic disease in cats, characterized by granulomas in organs and granulomatous vasculitis. This study describes the morphologic features of granulomatous vasculitis in FIP as well as its development in the course of monocyte-associated feline CoV (FCoV) viremia in five naturally infected Domestic Shorthair cats with FIP. Monocyte-associated FCoV viremia was demonstrated by immunohistology, RNA in situ hybridization, and electron micropscopy. Granulomatous phlebitis at different stages of development was observed. Vasculitic processes ranged from attachment and emigration of FCoV-infected monocytes to vascular/perivascular granulomatous infiltrates with destruction of the vascular basal lamina. Monocytes as well as perivascular macrophages were activated because they were strongly positive for CD18 and expressed cytokines (tumor necrosis factor-alpha and interleukin-1beta) and matrix metalloproteinase-9. In addition, general activation of endothelial cells, represented by major histocompatibility complex II upregulation, was observed in all cases. These results confirm FIP as a monocyte-triggered systemic disease and demonstrate the central role of activated monocytes in FIP vasculitis.  相似文献   

16.
The objective of the study was to analyze changes in peripheral blood leukocyte subsets in cases of naturally occurring exudative epidermitis (EE) in pigs. Five of ten piglets developed the chronic clinical form of EE 2-5 days after weaning (PW). Blood samples were obtained at 7, 14 and 21 days from both normal and clinically affected piglets for routine haematology and for the determination of CD45, CD21, CD4, CD8 and gammadeltaTCR cell markers by flow cytometry. When compared with clinically normal piglets EE affected pigs showed significantly decreased values of monocytes at 14 and 21 days PW, and increased numbers of neutrophils and leukocytes at 21 days PW. The EE affected pigs also had an early significant CD4(+) and CD8(high+) T lymphocyte proliferative response at 7 days PW. However affected pigs had a significantly reduced number of B (CD21(+)) and gammadeltaTCR(+) T lymphocytes in blood at 21 days PW. Although all values remained within the normal range, the significant differences in some peripheral blood leukocyte subsets between the two groups of piglets suggest that the generalised cutaneous infection with Staphylococcus hyicus is severe enough to induce a systemic inflammatory and immune responses.  相似文献   

17.
The larval stage (syn Cysticercus bovis) of the human tapeworm Taenia saginata causes cysticercosis in cattle, which has both aesthetic and food safety implications to consumers of beef. A monoclonal antibody-based immunohistochemical (IHC) assay developed to improve postmortem diagnosis of this parasite and a standard histological method were assessed to determine their fitness for intended use. Sections from 169 known-positive specimens of T. saginata from experimentally or naturally infected cattle, and from 30 known-negative specimens and lesions of various etiologies from non-infected cattle, were tested. The IHC assay identified significantly more known positive bovine cysticerci than the histological method (91.7% and 38.5%, respectively). Positive IHC staining occurred on sections from other cestode species, but should not affect the diagnostic specificity of this assay for bovine cysticercosis, due to the different host and/or tissue preferences amongst these parasites. Use of the IHC assay should improve the reliability of diagnosing lesions caused by degenerated cysticerci, facilitating more effective and efficient control of bovine cysticercosis.  相似文献   

18.
Monoclonal antibodies (mAbs) were generated against a CD44 mRNA expressing (RT-PCR) macrophage/monocyte cell line (DH82) from a dog with malignant histiocytosis. The mAbs, that reacted with DH82 cells by FACS analysis were tested on formalin-fixed, paraffin-embedded tissues. Exclusively the incubation of DH82 cell pellets with mAbs from clone 2D10 resulted in a cell membrane associated immunoreaction. Immunoelectron microscopy specified, that the antibody bound exclusively to the cell membrane and processes of DH82 cells. The mAb was tested on a variety of normal canine tissues, including lymphoid, urinary, alimentary, respiratory, and endocrine organs, nervous tissues, liver, pancreas, skin, and muscles. Furthermore, tumour and inflamed tissues were tested for immunoreaction with the mAb. Immunohistologically, the 2D10 mAb reacted with macrophages/monocytes, subsets of lymphocytes, epithelial cells, and central nervous system white matter. FACS analysis of canine peripheral blood leukocytes showed, that a high proportion of lymphocytes and granulocytes were positive with this mAb. Western blot analysis revealed, that the 2D10 mAb bound to a protein with a molecular weight of about 85 kDa. The results of FACS and Western blot analyses, RT-PCR, immunohistology and immunoelectron microscopy strongly suggest that the antigen detected by the 2D10 mAb is most likely the canine equivalent of human CD44, a cell bound hyaluronan binding proteoglycan.  相似文献   

19.
Canine distemper virus (CDV) belongs to the genus Morbillivirus of the Paramyxoviridae family. Due to the central nervous system (CNS) tropism of the virus and associated neuropathological changes, demyelinating canine distemper encephalitis (CDE) represents a relevant model for human demyelinating diseases like multiple sclerosis. The present review decribes the role of CD44 antigen (CD44), the principle cell surface receptor for hyaluronate and extracellular matrix (ECM) processing enzymes (matrix metalloproteinases [MMPs]) and their inhibitors (TIMPs) in the pathogenesis of demyelination. In acute and subacute CDE, a plaque-associated CD44 up-regulation is found that parallels astrocyte activation. Likewise, MMPs and TIMPs are prominently up-regulated in these lesions and are expressed mostly by astrocytes and microglia. In chronic lesions, CD44 expression declines together with the number of glial fibrillary acidic protein (GFAP) positive astrocytes. In addition, in this plaque type, CD44 is expressed on the cell membrane of perivascular mononuclear cells. In this phase, a decrease of MMP and TIMP expressions apart from MMP-11, -12, and -13 is obvious. In summary, CD44 and MMPs might be associated with the onset of demyelination and may interact to initiate ECM disturbances. Ligation of CD44 in the early phase may induce chemokines and cytokines and hence initiate and perpetuate the inflammatory process. In the chronic phase, it is conceivable that a MMP-TIMP imbalance may be the motor for lesion progression with a simultaneous influx of CD44-positive activated immune cells.  相似文献   

20.
MicroRNAs (miRNAs) are a family of regulatory molecules involved in many physiological processes, including activation of cells of the immune system. This study investigated the effect of Escherichia coli lipopolysaccharide (LPS) and Staphylococcus aureus enterotoxin B (SEB) on the expression of five miRNAs involved in the inflammatory response, including miR-9, miR-125 b, miR-155, miR-146 a and miR-223, in bovine CD14(+) cells (monocytes). Incubation of monocytes with SEB induced down-regulation of miR-155, miR-223 and miR-125 b, but not the anti-inflammatory miRNA miR-146 a. Conversely, incubation with LPS upregulated both miR-155 and miR-146 a. In vitro incubation of isolated CD14(+) bovine monocytes with LPS and SEB elicited different and opposite expression of miRNAs reportedly involved in inflammatory reactions.  相似文献   

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