Studies On Application Of Immunohistochemistry Test On Diagnoses Of Marek's Disease And Avian Leucosis

In this study, the immunohistochemistry test-SP method with specific antibodies was applied to test the relevant antigens in several different tissues from the SPF chickens infected by virulent MDV or ALSV.The results showed that, SP method was applicable to test the relevant antigens in tissues from chicken infected by MDV and ALSV, it could provide pathogenically evidence for clinical diagnosis. The main results were below:1. A typical MD had been replicated out by using virulent MDV Jing-1 strain stored in liquid nitrogen to infect 2-day-old SPF chickens, the disease occurred at about 17 day-old with death, the macro lesions displayed mainly on liver, spleen, proventriculus and kidney; A typical Avian leucosis (AL) had not been replicated out by using freeze-dried virulent ALSV RAV strain to infect chickens with the same age by the same way within 12 weeks, but the infection was successful.2. SP method was used to test MDV-gB antigen (MDV-gBAg) and ALV-p27 group specific antigen (ALV-p27gsa) in whole blood smears or tissue paraffin sections of negative and positive chickens with specific mouse anti-chicken MDV-gB monoclonal antibody and rabbit anti-chicken ALV-p27 IgG, the results showed that SP method had a good specificity.3. SP method and ELISA were compared by testing ALV-p27gsa in the blood of positive chickens, the results showed that the sensitivity of the former was at least 4 times of the one of the latter.4. SP method was used to.test ALV-p27gsa in the tissue paraffin sections of hearts, livers, spleens, lungs, kidneys, proventriculi, bursas, and blood smears of ALSV positive chickens, the results showed that there were positive substances in all tissue sections and the positive substances appeared commonly in a few white-blood-cell-like cells of the tissue sections, but in the cytoplasmas of parenchymal heart cells largely and of some renal tubular epithelial cells; the positive ratio of whole blood smear was 93. 33%, the positive substances also appeared in a few white-blood-cell-like cells.5. SP method was used to test MDV-gBAg in tissue paraffin sections of hearts, livers, spleens, lungs, kidneys, proventriculi, bursas, skins, and blood smears of MDV positive chickens, the results showed that the found ratios of liver, spleen, lung and skin were the highest (arrived at 100%), the ones of proventriculus and bursa were the second (arrived at 88.89%), the ones of kidney and heart were lower (33.33%, 22.22%, respectively). The positive substances appeared mainly in white-blood-cell-like cells.6. It was the first time to apply SP method to test MDV-gBAg and ALV-p27gsa in whole blood smear in this study. The research results showed that the sensitivities of testing MDV and ALSV in positive chickens were 85. 19% and 93. 33% respectively, so SP method could apply to diagnose MDV and ALSV infection in live chicken.