| Avian encephalomyelitis (AE), characterized by non-suppurative encephalomyelitis, was firstly reported in 1930 by Jones in US and formally named by American veterinary medical association (AVMA) in 1939. The disease was world-wide spread and lead to huge loses for the chicken industry, especially for the breeding industry. In 1980S along with the import of fine breed of chicken and embryos, it was transmitted into china. The scientists all over the world and China made great contribution in the research of AE. Since 1991, the teaching group of veterinary pathology in Inner Mongolia Agricultural University have accomplished 3 research subjects supported by the National foundation of science and technology. In the process of research, a local AEV strain, the AVE-NH937 strain, was isolated and established. The detailed pathological lesions and the dynamic location of AEV in natural and experimental cases of chicken, chickling and embryos were reported. And AEV agar gel precipitin antigen and an inactivated oil-emulsion vaccine against AE were produced. The purpose of this study, on the base of former research, was to reveal and better understand some molecular pathogenesis of AE, to set up a working model which could be generally used by anther researcher in the field of animal molecular pathology. One-day-old SPF chicklings were inoculated via intracephalic injection at a dose of 0.03ml per chickling, consisting of 1:100 (w/v) tissuer virus suspension. And 4 of experimental group and 2 of control group were killed at 1, 3, 5, 10, 14, 20, 25 and 30 days postinfection, respectively. All the sera, the lymphocyte suspension of peripheral blood, thymus, Fabricius bursa and spleen, were collected. The brains were fixed in 10% formalin for preparing waxy embeded sections. The following methods were used in the study, such as viral inoculation of animal, pathological method, flow cytometry, RT-PCR, in situ hybridization, immunohistochemistry and terminal deoxy nucleotidyl transferase mediated dUTP nick end labling (TUNEL). Morphological changes of the infected chickling, dynamic changes of T, B cells and T subsets, changes of adhesion molecules on the lymphocyte surface, necrosis and apoptosis of lymphocyte and neurons, changes of MIP-1β and IL-8 producing cells in the brain, cell types of perivascular tuffing in cerebral tissue were systematically studied. The key research results were. (1)The average percentage of CD19+cell (B cell) in blood, bursa and spleen, after 3, 5 days of inoculation, was significantly (P<0.05) higher than that of control (some were not significant). While B cells turned into plasma cells, they lost their CD19, so the number of CD19+cell was decreased. Considering of the serum IgM, IgG content, it was proved that humeral immunity played important role against the AEV-NH937 strain infection at the beginning of the disease. (2) The average percentage of CD18+ (β2 integrin family), CD31+(PECAM-1) T cells, during 3～10 days after inoculation, was significantly (P<0.05) higher than that of control, among these some were not significant. It was proved that the lymphocytes in the non-suppurative encephalomyelitis derived from the up-expression of adhesion molecules on the surface of lymphocytes. (3)Cloning and sequencing of chicken IL-8 (interleukin-8) and MIP-1β(macrophage inflammatory protein-1β) were firstly reported in china. Analysis of the chicken IL-8 cDNA and MIP-1βcDNA showed that the homology identity to the literature was 100% and 98%, respectively. Digoxin labeled IL-8 and MIP-1βprobes were prepared. The result of in situ hybridization revealed that the number of IL-8 and MIP-1βproducing cells was increased in the infected brain. It proved that chemokines IL-8 and MIP-1βprovided directional information for the movement of lymphocytes in inflammation and tissue homing. (4) Staining the brain section by means of FITC and R-PE labeled anti-CD3, CD4, CD8 monoclonal antibodies, the result of immunohistochemistry revealed, that the main infiltrated cells, including the perivascular...
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