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1.
Haemal nodes are lymphoid organs found in various mammals and some birds. The structure of haemal nodes has been described in a number of species but not yet in the camel. Therefore, haemal nodes from 10 camels were studied histologically and tested for CD3, CD22, major histocompatibility complex (MHC) class II/DR, alpha-smooth muscle actin and for the demonstration of acid and alkaline phosphatases. The haemal nodes were of spherical or kidney shape with one or two hili and had a capsule and trabeculae of connective tissue and smooth muscles. The main parenchyma was composed of a cortex and a medulla. The cortex was formed from lymphoid follicles and diffuse interfollicular lymphocytes. The medulla consisted of lymphoid cords separated by medullary sinuses. The interfollicular lymphocytes and those in the medullary cord were CD3-positive. The lymphoid follicles showed CD22-positive cells. MHC class II/DR was expressed by most cells of the parenchyma. There were also subcapsular, peritrabecular and medullary blood sinuses. Afferent and efferent lymphatics and lymphatic sinuses were also found. Acid phosphatase-positive cells were localized mainly in the marginal, the interfollicular zone and in the medullary cord. Alkaline phosphatase positivity was observed in the endothelium of the sinuses and in the lymphoid follicles. The morphology of these organs in the camel allows a classification as haemolymph nodes and suggests involvement in blood and lymph filtration.  相似文献   

2.
流行性白血病病牛的免疫病理学观察   总被引:4,自引:1,他引:3  
用8种单克隆抗体(TH14B、BAQ44A、BIg45A、BIg715A、BIg501E、CACT105A、MM1A、AH-CC125)结合常规病理学方法,对10头流行性白血病病牛的免疫病理学进行了观察。结果:患病较轻时,淋巴结内的淋巴小结肿大,生发中心明显,副皮质区显著增宽。脾脏中的脾小体亦增大,动脉周围淋巴鞘增厚。用McAb证明,在淋巴结和脾脏有较多的B淋巴细胞和大量T淋巴细胞。患病较重时,淋  相似文献   

3.
The reactivity of five monoclonal antibodies (mAbs SBU-T19, 197, IL-A29, CC-15 and CC-39) specific for the T19 molecule on sheep and cattle CD4-CD8- T cells was compared. MAbs SBU-T19 and 197 were shown to recognise separate epitopes on T19. All mAbs reacted with lymphocytes from several different ruminant species and the tissue distribution and frequency of positive cells was similar in each case. None of the mAbs reacted with horse, pig or camel lymphocytes. The extensive conservation of T19 epitopes in ruminants during the mammalian radiation could indicate an important role for this molecule in the ruminant immune system.  相似文献   

4.
Direct immunofluorescence and fluorescence-activated cell sorter techniques were used for the detection of surface immunoglobulin positive (SIg+) cells in peripheral blood lymphocytes (PBL's) of bovine leukaemia virus (BLV) infected cattle with or without persistent lymphocytosis (PL+, PL-) and in BLV-free cattle. The percentage of SIg+ cells was more than twice as high in BLV+PL+ cattle than in BLV-free and BLV+PL- cattle. Bovine T cells, and T cell subsets were identified indirectly by the same techniques using three monoclonal antibodies (MAb's) specific for all T cells (IL-A43), T helper (BoT4) cells (IL-A12) and T cytotoxic (BoT8) cells (IL-A17). The major histocompatibility complex (MHC) determinants of both class II (BoT4) and class I (BoT8) as well as all T cells were significantly reduced in BLV+PL+ compared to BLV-free cattle. The actual decrease in the BoT8 cell subset or the dilution effect that would change effector:target cell ratio suggests that a resultant decrease in cytotoxic activity in BLV+PL+ cattle may play an important role in the progress of BLV infection in cattle.  相似文献   

5.
Infection with a retrovirus, Jaagsiekte sheep retrovirus (JSRV), causes ovine pulmonary adenocarcinoma (OPA). The excess production of surfactant proteins by alveolar tumour cells results in increased production of pulmonary fluid, which is characteristically expelled through the nostrils of affected sheep. The immune response to JSRV and the tumour is poorly understood: no JSRV-specific circulating antibodies or T cells have been detected to date. The aim of the present study was to obtain phenotypic evidence for a local immune response in OPA lungs. Specific-pathogen free lambs were infected intratracheally with JSRV. When clinical signs of OPA were apparent, the lungs were removed at necropsy and immunohistochemistry (IHC) was performed on lung sections using a panel of mouse anti-sheep mAbs. No influx of dendritic cells, B cells, CD4, CD8 or gammadelta T cells was seen in the neoplastic nodules or in their periphery. MHC Class II-positive cells were found intratumourally, peritumourally and in the surrounding alveolar lumina. In the tumours, many of these cells were shown to be fibroblasts and the remainder were likely to be mature macrophages. In the alveolar lumen, the MHC Class II-positive cells were CD14-positive and expressed high levels of IFN-gamma. They appeared to be immature monocytes or macrophages which then differentiated to become CD14-negative as they reached the periphery of the tumours. A high level of MHC Class I expression was detected on a range of cells in the OPA lungs but the tumour nodules themselves contained no MHC Class I-positive cells. On the basis of these findings, it is proposed that the lack of an effective immune response in OPA could result from a mechanism of peripheral tolerance in which the activity of the invading macrophages is suppressed by the local environment, possibly as a consequence of the inhibitory properties of the surfactant proteins.  相似文献   

6.
This study was carried out on spleens of clinically healthy camels (n = 35) of both sexes (0.5-15 years) by routine histology, electron microscopy and immunohistochemistry using 12 anti-bovine platelet antibodies. Megakaryocytes were observed in the red pulp. Their number decreased with age: they were found in the spleens of all camels under 8 years old but only in 57% of camels over 8 years old. Only two antibodies (IVA37 and IVA38) cross-reacted with camel platelets. A large number of platelets were found in the splenic cords and the marginal zone. Ultrastructurally, the platelets were oval in shape surrounded by a plasma membrane, and their cytoplasm was rich in glycogen and contained less dense granules. Microtubules and microfilaments were found at their periphery. Several platelets were observed in the red pulp. There are similarities in some surface antigens of bovine and camel platelets. The presence of megakaryocytes in the camel spleen indicates a thrombopoietic function of the spleen until adulthood but that this decreases with age thereafter.  相似文献   

7.
The present study describes immunophenotypic characteristics of inflammatory infiltrate in the skin and lung of lambs naturally infected with sheeppox virus (SPV). Three lambs revealed typical cutaneous and pulmonary lesions of sheeppox. Histologically, cutaneous and pulmonary lesions consisted of hyperplastic and/or degenerative changes in the epithelium with mononuclear cells, neutrophils, and typical sheeppox cells (SPCs), which had a vacuolated nucleus and marginated chromatin with occasional granular intracytoplasmic inclusions. The inflammatory infiltrate in pox lesions in both skin and lung was characterized by the presence of MHC II+ dendritic cells, CD4+, CD8+, gammadelta+ T cells, IgM+ cells, and CD21+ cells. Loss of expression of MHC I and MHC II antigens was observed in the affected areas of skin and lung. SPCs, stained with anti-SPV antibody, were also positive for CD14 and CD172A, antigens expressed on monocytes and macrophages. CD14 and CD172A negative SPCs were considered to be SPV infected degenerated epithelial cells or fibroblasts.  相似文献   

8.
A sub-population of circulating porcine gammadelta T cells express cell surface antigens associated with antigen presenting cells (APCs), and are able to take up soluble antigen very effectively. Functional antigen presentation by gammadelta T cells to memory helper T cells was studied by inbred pig lymphocytes immunised with ovalbumin (OVA). After removing all conventional APCs from the peripheral blood of immunised pigs, the remaining lymphocytes still proliferated when stimulated with OVA. When gammadelta T cells were further depleted, OVA specific proliferation was abolished, but reconstitution with gammadelta T cells restored proliferation. The proliferation was blocked by monoclonal antibodies (mAb) against MHC class II or CD4, and by pre-treatment of gammadelta T cells with chloroquine. These results indicate that a sub-population of circulating porcine gammadelta T cells act as APCs and present antigen via MHC class II.  相似文献   

9.
研究脑炎原虫病兔外周免疫器官的形态学变化,采集20只病兔和12只对照兔的淋巴结、脾脏和圆小囊,通过临床检查,病理剖检,病理切片的HE染色、吉姆萨染色和免疫组织化学染色进行了比较观察。结果表明病兔淋巴结内的淋巴小结数量增多,生发中心明显,髓索增粗,副皮质区增宽。脾脏的脾小结增多,变大,具有明显的生发中心,边缘区明显增宽,动脉周围淋巴鞘明显变大,聚集大量淋巴细胞。圆小囊的淋巴小结增大,数量增多,生发中心明显,淋巴小结周围弥散大量淋巴细胞。通过α-ANAE和sABC染色,在淋巴结、脾脏和圆小囊中均可检出大量T细胞、巨噬细胞和IgG阳性细胞。据此认为患脑炎原虫病时,病兔的体液免疫和细胞免疫均增强,但以细胞免疫反应更强。  相似文献   

10.
Five monoclonal antibodies (MAb) produced against cell surface antigens on bovine mononuclear phagocytes (MPh) were characterized. None of the MAb recognized erythrocytes, thrombocytes, B lymphocytes or resting or activated T lymphocytes. Two MAb (IL-A22 and IL-A24) reacted with the majority of monocytes and granulocytes in peripheral blood, with 20-40% bone marrow cells comprising myelo-monocytic cells, and with a proportion of mature macrophages. Reactivity of the remaining three MAb was restricted to MPh: one of these (IL-A25) was apparently specific for pulmonary macrophages, whereas the molecules recognized by the other two (IL-A23 and CH16A) were expressed on subpopulations of blood monocytes and tissue macrophages. None of the MAb inhibited adherence of MPh to plasma-coated gelating surfaces or Fc-mediated rosette formation. One of the MAb, IL-A24, which reacts with MPh and granulocytes, inhibited antigen-specific proliferative response or peripheral blood mononuclear leukocytes (PBM) to the soluble antigen, keyhole limpet hemocyanin (KLH) but did not inhibit responses to concanavalin A or allogeneic leukocytes. This MAb was shown to react with two polypeptides of approximately 75 kD and 110 kD on the surface of peripheral blood monocytes.  相似文献   

11.
Many monoclonal antibodies reactive with bovine leukocyte differentiation antigens are now available. Immunohistochemical staining on frozen sections using these monoclonal antibodies permits study of the functional morphology of bovine spleen. This study confirms accepted notions (B and T dependent-zones) and supplies complementary data about the repartition of CD4 and CD8 cells. γδ cells. MHC (Major Histocompatibility Complex) II expression, and macrophages.  相似文献   

12.
Monoclonal antibodies (mAb) which react with bovine monocytes have been produced. These include three mAb (P8, IL-A22 and IL-A24) that recognize the majority of monocytes and granulocytes in peripheral blood; two of these mAb were also shown to react with 30-40% of cells in bone marrow, including both monocytic and granulocytic cells, and with variable percentages of tissue macrophages. Thus these mAb can act as markers for myeloid cells in haemopoietic tissues and for monocytes in cell populations devoid of granulocytes. A further two mAb (IL-A23 and IL-A25) recognize monocytes and/or macrophages. The reactivity of one of these mAb (IL-A25) appears to be mainly restricted to pulmonary macrophages. The other mAb reacts with a variable proportion of blood monocytes and generally with a higher percentage of tissue macrophages, suggesting that its expression may relate to activation or maturation of monocytes. In order to study the functional properties of peripheral blood monocytes, techniques were developed for obtaining populations of peripheral blood mononuclear cells (PBM) depleted of monocytes to less than 0.2% and monocyte populations of greater than 97% purity. Removal of monocytes from PBM abrogated the capacity of the cells to proliferate in response to Con A and PBS, although addition of 2-mercaptoethanol to the cultures restored proliferation. In both allogeneic and autologous mixed leukocyte cultures (MLC), monocytes were required in the stimulator cell populations for induction of the proliferative responses, and both responses could be elicited with purified monocytes. However, proliferation in the autologous MLC occurred only with responder cell populations that were depleted of monocytes. Moreover, it was shown that addition of more than 5% unirradiated monocytes to the autologous MLC suppressed proliferation. These findings indicate that monocytes play an important role in the induction and regulation of cellular immune responses in cattle. Two of the mAb that react with monocytes and granulocytes were tested for their capacity to inhibit proliferative responses of PBM to mitogens, alloantigens or the soluble antigen, KLH.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

13.
In order to develop procedures to label the main bovine leucocyte populations in paraffin embedded sections, the immunoreactivity of 25 monoclonal antibodies (mAbs) to different leucocyte antigens was assessed with formal dichromate (FD5) and 10% formalin fixation, a battery of antigen retrieval (AR) methods, and the biotin-tyramide amplification system. All the leucocyte populations investigated (CD2+, CD4+, CD8+, WC1+ T lymphocytes, B cells and macrophages) were strongly and specifically detectable under an appropriate combination of mAb, AR method and signal amplification system. CD4 and CD8 required the most stringent conditions and could only be demonstrated in FD5 fixed sections. For detection of CD2, WC1+ T lymphocytes, B cells and macrophages, all the mAbs produced immunoreactivity in FD5 or formalin fixed tissues. The need to check a range of different AR methods is stressed, as the method of choice varied for each individual mAb. The incorporation of the signal amplification system was necessary to observe a strong signal and the complete distribution of CD4, CD8 and B cells. Fixation by FD5 proved to be better than formalin for the preservation of surface antigens but it was inferior for the detection of markers which were found to show cytoplasmic immunoreactivity, such as the macrophage marker MAC387 or the B cell markers BAQ155 or IL-A59.  相似文献   

14.
This study was undertaken to investigate the immunohistochemical characterization of different subpopulations of macrophages and dendritic cells (DCs) of the spleen, thymus, tongue and heart in cyclophosphamide (CY)-induced immunosuppressed rat. After CY treatment, remarkably, ED1+, ED2+ and ED3+ macrophage subpopulations, in general exhibited signs of cellular activation such as an increase in number and size of cell, and an upregulation of the ED1, ED2 and ED3 reactive surface molecule expression in all the organs studied, except for some macrophage subpopulations including ED1+ macrophages in the non-lymphoid tissues. Subpopulations of DCs showed a differential sensitivity to CY. Lymphoid DCs were more sensitive to CY than non-lymphoid interstitial DCs. CY induced a conspicuous upregulation of intercellular adhesion molecule-1 (ICAM-1) expression in the vascular endothelial cells, splenic marginal zone and thymic cortex. In this study, we demonstrated the in vivo effects of CY treatment on subpopulations of macrophages and DCs as well as on ICAM-1 expression in the rat spleen, thymus, tongue and heart. Moreover, our results shed more light on the activation effects of CY on certain subpopulations of macrophages, on the differential sensitivity of DCs to CY between the immature and mature ones, on the functional role of different subpopulations of macrophages, and on the significance of upregulated ICAM-1 expression in the splenic marginal zone and thymic cortex after CY treatment.  相似文献   

15.
The functional role of subpopulations of bovine cells in the regulation of pokeweed mitogen (PWM)-induced proliferative and antibody responses of peripheral blood mononuclear cells (PBM) was analysed. Subpopulations of bovine PBM identified by specific monoclonal antibodies (mAbs) were isolated by sorting them through the fluorescence activated cells sorter (FACS). The depletion from PBM of T cells bearing the CD4 marker, recognised by mAb IL-A12, resulted in a reduction of PWM-induced responses, which could be partly reversed by the addition of CD4 positive T cells. The depletion of cells belonging to the macrophage/monocyte lineage also resulted in a reduction of PWM-induced proliferative responses. PBM depleted of CD8 positive T cells, recognised by mAb IL-A51, showed increased PWM-induced responses, which in turn were reduced by the addition of mAb IL-A51 positive cells. Proliferative and antibody responses were also obtained by PWM stimulation of FACS-purified B cells, in the presence of bovine T cell growth factor.  相似文献   

16.
T cell activity is a critical component of immunity to bovine respiratory syncytial virus (BRSV). We tested the effects of immunization by modified-live and inactivated BRSV vaccines on cell-mediated and humoral immunity in young calves. The two forms of vaccine stimulated similar serum neutralizing antibody production, although the early kinetics of those responses differed. CD4+, CD8+, and gammadelta T cells were analyzed before and after immunization for BRSV-specific in vitro recall responses, as evaluated by CD25 upregulation measured by flow cytometry. Modified-live virus (MLV) primed each of the three subsets for statistically significant in vitro responses to antigen. Inactivated vaccine also primed each T cell population for significant antigen-driven CD25 upregulation, including responses by CD4+ and gammadelta T cells that were stronger and longer-lasting than those primed by MLV. Monoclonal antibody was used in additional assays to block MHC class I during incubation of BRSV antigen with peripheral blood mononuclear cells from an animal in the inactivated vaccine group. The recall response by CD8+ T cells was more inhibited by this treatment than the other subsets, further suggesting that the inactivated vaccine had primed antigen-specific CD8+ T cells. In summary, the data indicate that balanced BRSV-specific T cell responses can be induced by inactivated, as well as modified-live, conventional vaccines, which may implicate an alternative pathway of MHC class I antigen presentation.  相似文献   

17.
The function of gammadelta T cells during ruminant paratuberculosis (Johne's disease) is presently unknown. An ex vivo system was used to test the hypothesis that gammadelta T cells are capable of activating Mycobacterium avium subsp. paratuberculosis-(M. paratuberculosis)-infected macrophages. Peripheral blood-derived macrophages were infected in vitro with live M. paratuberculosis, and autologous LN-derived gammadelta T cells or CD4+ T cells were co-cultured with infected macrophages for 48h, at which time bacterial survival as well as production of nitrites and IFN-gamma was evaluated. Incubation of M. paratuberculosis-infected macrophages with autologous gammadelta T cells did not result in reduced intracellular bacterial viability compared to infected macrophage cultures without added T cells. IFN-gamma production by-infected cultures containing added gammadelta T cells was not enhanced compared to that of infected macrophages alone. Although infection of macrophage cultures caused increased production of nitrites at both post-infection day (PID) 0 and PID 60, the addition of gammadelta T cells did not further increase nitrite production. In contrast, addition of PPD-stimulated CD4+ T cells obtained at PID 60 to M. paratuberculosis-infected macrophages resulted in significantly increased IFN-gamma production compared to cultures without added T cells or cultures containing unstimulated CD4+ T cells or unstimulated or antigen-stimulated gammadelta T cells. However, the increased production of IFN-gamma by co-cultures containing PPD-stimulated CD4+ T cells did not result in increased bacterial killing or increased production of nitrites compared to cultures without added T cells. In additional in vitro experiments, M. paratuberculosis-infected macrophages, but not uninfected macrophages, were unable to increase nitrite production when stimulated with recombinant IFN-gamma. Taken together, the data suggest that (1) gammadelta T cells do not produce significant IFN-gamma and do not significantly increase NO production from M. paratuberculosis-infected macrophages in vitro, (2) the production of significant IFN-gamma by antigen-stimulated CD4+ T cells from infected calves is insufficient to enhance mycobacterial killing or nitrite production by infected macrophages, and (3) macrophages may have an impaired NO response following intracellular M. paratuberculosis infection, even in the presence of significant concentrations of IFN-gamma.  相似文献   

18.
Two new monoclonal antibodies (CC17 and CC29) raised against bovine thymocytes are described. The antibodies, both of which were IgG1, recognize a molecule of approximately 67,000 molecular weight on bovine T cells. They react T cells in peripheral blood, the lymph node paracortex and the periateriolar lymphoid sheath in the spleen. Both the cortex and medulla of the thymus are stained but the medulla reacts more intensely. They do not stain B cells in peripheral blood, the ileal Peyer's patch, the cortex or the primary follicles in lymph nodes. No activity was found on cells outside the lymphoid system, i.e. monocytes, alveolar macrophages or endothelial and epithelial tissue. The antigen recognized is considered to be the bovine homologue of CD5 (T1) in humans and Lyt1 in mice. The mAbs appear to be particularly useful for detecting cells in the peripheral blood of young calves which are of the T cell lineage but do not express BoT2 or the mature pan T cell antigen recognized by mAb IL-A27 and may thus allow identification of a population of bovine lymphocytes previously described as null cells.  相似文献   

19.
The present review concentrates on the biological aspects of porcine T lymphocytes. Their ontogeny, subpopulations, localization and trafficking, and responses to pathogens are reviewed. The development of porcine T cells begins in the liver during the first trimester of fetal life and continues in the thymus from the second trimester until after birth. Porcine T cells are divided into two lineages, based on their possession of the alphabeta or gammadelta T-cell receptor. Porcine alphabeta T cells recognize antigens in a major histocompatibility complex (MHC)-restricted manner, whereas the gammadelta T cells recognize antigens in a MHC non-restricted fashion. The CD4+CD8- and CD4+CD8lo T cell subsets of alphabeta T cells recognize antigens presented in MHC class II molecules, while the CD4-CD8+ T cell subset recognizes antigens presented in MHC class I molecules. Porcine alphabeta T cells localize mainly in lymphoid tissues, whereas gammadelta T cells predominate in the blood and intestinal epithelium of pigs. Porcine CD8+ alphabeta T cells are a prominent T-cell subset during antiviral responses, while porcine CD4+ alphabeta T cell responses predominantly occur in bacterial and parasitic infections. Porcine gammadelta T cell responses have been reported in only a few infections. Porcine T cell responses are suppressed by some viruses and bacteria. The mechanisms of T cell suppression are not entirely known but reportedly include the killing of T cells, the inhibition of T cell activation and proliferation, the inhibition of antiviral cytokine production, and the induction of immunosuppressive cytokines.  相似文献   

20.
The distribution of mononuclear cells isolated from the bovine mammary gland during the nonlactating (dry) period was examined using monoclonal antibodies against leukocyte cell surface antigens, cellular light scattering properties, and the presence of nonspecific esterase. Most of the mononuclear cells isolated during the dry period were lymphocytes. T cells predominated until about 1 week prior to parturition. During the week prior to calving, the percentage of B cells increased until it approximated T cells. The ratio of CD4:CD8 cells was 2-3:1 for mammary gland T cells. This was similar to the ratio found in peripheral blood. At dry-off, about 12% of mammary mononuclear cells were macrophages. The macrophage percentage increased (to about 30%) at mid-dry and remained at this levels until parturition. PMN's were isolated with the mononuclear cells during the first 2 weeks dry and the week prior to calving. Three methods were used to identify mammary macrophages. Esterase staining (as an enzymatic method), forward angle/90 degrees light scatter (based on size and internal complexity), and MHC class II/forward angle light scatter (based on size and surface markers) were compared. Each method yielded similar specificity for macrophage identification. Non-adherent cell fractions, obtained by passage of the cells over Sephadex G-10 columns, were enriched in CD4 positive T cells, somewhat depleted of B cells, and depleted of macrophages and PMN's. Cells eluted from G-10 columns, with lidocaine, were mostly lymphocytes, but reflected the cells loaded onto the column.  相似文献   

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