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Reactivity of polyclonal human CD3 antiserum in lymphoid tissues of cattle, sheep, goats, rats and mice.
1994
Ramos Vara J.A. | Miller M.A. | Lopez E. | Prats N. | Brevik L.
Polyclonal rabbit antiserum to human T-cell CD3 was used to study its reactivity in lymphoid tissues (lymph nodes, spleen, aggregated lymphoid follicles [Peyer's patches], thymus) of several animal species (cattle, sheep, goats, rats, and mice). Using a peroxidase-antiperoxidase technique on formalin-fixed and paraffin-embedded tissues, immunoreactive cells were detected in T cell-dependent areas of the lymphoid tissues. Reactivity was high in all species tested, but mouse tissues had reduced reactivity, compared with the other species. To obtain a reaction, it was necessary to digest tissues with pronase before application of the immunocytochemical technique. Our results indicate that CD3 antiserum may specifically recognize T-lymphoid cells as it does in human lymphoid tissues and can be used as a marker to study physiologic and pathologic conditions of the lymphoid system of these species.
Показать больше [+] Меньше [-]Immunopathologic study and characterization of the phenotype of transformed cells in sheep with bovine leukemia virus-induced lymphosarcoma.
1994
Murakami K. | Aida Y. | Kageyama R. | Numakunai S. | Ohshima K. | Okada K. | Ikawa Y.
We used monoclonal antibodies and immunohistologic examination of lymph nodes, to elucidate the pathogenesis of lymphosarcoma induced by, infection with bovine leukemia virus (BLV). The superficial cervical lymph nodes from 3 BLV-infected but apparently healthy sheep and 5 sheep with full-blown lymphosarcoma were examined. We also investigated the integration of bovine leukemia provirus by use of Southern blotting. In lymph nodes from sheep lacking clinical signs of infection, in which the provirus had been integrated at multiple sites in the genome, many large hypertrophic follicles were observed in the cortex. These follicles had germinal centers consisting of CD4+T cells and B cells that expressed surface IgM (sIgM) and major histocompatibility complex (MHC) class-II antigens, but not B cell-specific B2 molecule. The percentage of CD4+T cells in the cortex was significantly (P < 0.05) higher than that of the controls and sheep with lymphosarcoma. In all sheep with lymphosarcoma, the lymph nodes were completely destroyed by proliferating neoplastic cells, and in addition, small atrophic follicles, which consisted of normal B-cell marker-positive cells, were seen near the trabecula and the subcapsule. In these instances, neoplastic cells appeared to be a monoclonal population derived from a single CD5- B-cell lineage and to be classified as 2 types, CD5-CD4-CD8-B2+MHC class-II+sIgM+ and CD5-CD4-CD8-B2+MHC class-II+sIgM-. Moreover, CD8+T cells infiltrated diffusely throughout the tumorous lymph nodes apart from the atrophic follicles, and CD4+T cells were observed around atrophic follicles. Both types of T cells were small-size, normal lymphocytes with round and noncleaved nuclei, and were apparently non-neoplastic cells. In fact, after separation by use of a panning method, it seems that, in blood mononuclear cells from BLV-infected sheep without clinical signs of infection, but in lymphosarcomatous stages, the proviral genome was integrated only in B cells.
Показать больше [+] Меньше [-]Bile enhances the infectivity of third stage larvae of Dictyocaulus filaria
1994
Titoy, G.A.P. | Schwan, E.V. (Onderstepoort Veterinary Inst. (South Africa). Helminthology Div.)
The identification of Mycoplasma conjunctivae as an aetiological agent of infectious keratoconjunctivitis of sheep in South Africa
1994
Van Halderen, A. | Van Rensburg, W.J.J. | Geyer, A. (Regional Veterinary Laboratory, Stellenbosch (South Africa)) | Vorster, J.H.
The clinical pathology of heartwater. III. Changes in blood clotting, blood calcium, blood protein, haematocrit and white-cell counts in sheep with experimentally induced heartwater
1994
Van Amstel, S.R. | Reyers, F. | Myburgh, E. | Pretorius, G. | Sacks, P. (Pretoria Univ., Onderstepoort (South Africa). Dept. of Medicine)
Changes in the blood-gas status of sheep with experimentally induced heartwater
1994
Van Amstel, S.R. | Reyers, F. | Myburgh, E. (Pretoria Univ., Onderstepoort (South Africa). Dept. of Medicine)
The virtual absence of Culicoides imicola (Diptera: Ceratopogonidae) in a light-trap survey of the colder, higher-lying area of the eastern Orange Free State, South Africa, and implications for the transmission of arboviruses
1994
Venter, G.J. | Meiswinkel, R. (Onderstepoort Veterinary Inst. (South Africa). Entomology Section)
Perinatal mortality in lambs of ewes exposed to cultures of Diplodia maydis (=Stenocarpella maydis) during gestation. A study of the central-nervous-system lesions
1994
Prozesky, L. | Swart, D.P. | Maartens, B.P. | Schultz, R.A (Onderstepoort Veterinary Inst. (South Africa)) | Kellerman, T.S.
Application of immunoperoxidase techniques to formalin-fixed brain tissue for the diagnosis of rabies in southern Africa
1994
Last, R.D. (Allerton Regional Laboratory, Pietermaritzburg (South Africa)) | Smit, M.M.E. | Van der Lugt, J.J.
Photosensitivity in South Africa. VII. Chemical composition of biliary crystals from a sheep with experimentally induced geeldikkop [disease contracted by ingestion of Tribulus terrestris]
1994
Miles, C.O. (Pretoria Univ., Onderstepoort (South Africa). Dept. Pharmacology and Toxicology) | Wilkins, A.L. | Erasmus, G.L. | Kellerman, T.S. | Coetzer, J.A.W.