Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038002 (splenomegaly)
 9,873 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The establishment and continuous culture of two lymphoblastoid cell lines derived from Marek's disease lymphomas is described. Although the cells carried T-lymphocyte surface antigens, they had many features in common with cultured Burkitt's lymphoma lymphoblasts, which carry B-cell determinants. A small proportion acted as infectious units in tissue culture, and a similarly small proportion contained intranuclear immature herpesvirus particles. The cells did not respond to phytohaemagglutinin. One cell line possessed some graft-versus-host capacity, as measured by the induction of splenomegaly. It is concluded that the development of acute Marek's disease involves the malignant transformation of thymus-dependent lymphocytes by Marek's disease virus.
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PMID:T-lymphoblastoid cell lines from Marek's disease lymphomas. 6 82

Marek's disease virus (MDV) and the turkey herpesvirus (HVT) may be assayed on the chorioallantoic membrane (CAM) of the chicken embryo after intravenous inoculation of chicken embryo fibroblasts (CEF) or chicken blood leukocytes infected with these viruses. Free HVT, MDV associated with Marek's tumor cells, and lymphoblastoid cell lines derived from Marek's tumors, may be assayed in the same way. The intravenous assay is quicker than the yolk sac assay and somewhat more sensitive than in vitro or conventional CAM assay after direct inoculation of the CAM. The optimal time for inoculation was day 10 of embryo incubation; therafter the log-10 CAM lesions decreased as a negative linear function of embryo age at the time of inoculation. The log-10 CAM lesions increased as a positive linear function of the time since inoculation. The optimal time for counts was day 5 after inoculation. The log-10 CAM lesions was a linear function of the log-10 cells in the inoculum; the slope was 1.0. Venous in ovo inoculation caused as increase in the weight of the spleen proportional to the number of CAM lesions. Repression of the splenomegaly, by prior X irradiation of the embryo, did not reduce the number of CAM lesions. Embryols from lines inbred for susceptibility to Marek's disease produced more CAM lesions than embryos from resistant lines. This difference did not depend on prior exposure of the mothers to MDV or HVT.
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PMID:In ovo assay for Marek's disease virus and turkey herpesvirus. 16 13

Three pairs of chicken lines selected for high (H) and low (L) graft vs. host reaction (GVHR) competences, serum immunoglobulin G (IgG) levels, and antibody responses to Leucocytozoon caulleryi were examined for their immunocompetences and Marek's disease (MD) resistance. The GVHR-H and GVHR-L lines were further divided into two sublines according to their major histocompatibility B genotype. Immune responses to sheep erythrocytes (SRBC), bovine serum albumin (BSA), and a lipopolysaccharide (LPS) were compared between the high and low lines of each pair of selected lines. Significant differences were found in responses to SRBC and LPS in IgG-selected lines and in response to BSA in Leucocytozoon-selected lines. In all three instances antibody titers of the H line were higher than those of the L line. The GVHR competence expressed by the splenomegaly index (SI) was also significantly different between the H and L lines of all three selected-line pairs. The SI values in the GVHR-selected and IgG-selected lines were higher in the H line than in the L line, whereas those in the Leucocytozoon-selected lines were lower in the H line. Differences in MD incidence and in MD mortality were found between the GVHR-selected B11B11 subline and the IgG-selected lines. In both instances the L line was more resistant to MD than the H line.
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PMID:Immunocompetences and Marek's disease resistance in three pairs of chicken lines selected for different immunological characters. 362 59

Two sets (four lines) of chickens, lines 7 and 6 and lines P and N, the former of each set susceptible and the latter resistant to Marek's disease, were examined for their relative histocompatibility and immunocompetence. Results from the in vivo graft-versus-host response splenomegaly assay, and graft-versus-host chorioallantoic membrane pock formation assay confirmed the within-line, B-locus homozygosity of chickens of lines 7, 6, and N and the heterozygosity of line-P chickens. These assays further confirmed that line-7 and line-6 chickens share identical alleles at the major histocompatibility locus. The capacity of the lines of chickens to elicit specific cell-mediated immune lysis as measured by the release of chromium 51 generally agreed with the in vivo graft-versus-host responses. These data demonstrate that the 51Cr-release assay is a reliable measure of histocompatibility within the avian system.
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PMID:Studies of histocompatibility and immune response of chickens selected for resistance and susceptibility to Marek's disease. 684 51

The Silkie is a typical Chinese breed of chicken. In 2012, batches of Silkies were found to have diffuse tumor-like nodules on their skin after feather removal, when they were slaughtered at about 60 days old. Gross examination showed no visible neoplastic lesions on the visceral organs and peripheral nerves, except slight splenomegaly in individual chickens. The disease was prevalent, with high condemnation rates for skin lesions, which caused great economic losses to the company. Tissues, including skin, visceral organs, and peripheral nerves, were collected for histologic examination. Heparinized blood samples were collected for virus isolation and identification. Marek's disease virus (MDV), Reticuloendotheliosis virus (REV), and Avian leukosis virus (ALV) were analyzed, using polymerase chain reaction (PCR) tests. Histologic examination showed that all of the tumor-like nodules on the skin were lymphomas. Lymphoproliferative lesions occurred mostly on the skin and only a few on the viscera, including the liver and proventriculus. Infected chick embryo fibroblasts showed clear cytopathic effects; indirect fluorescent antibody test for envelope glycoprotein B was positive. In addition, PCR indicated the presence of MDV serotype 1 infection without REV and ALV. A phylogenetic tree of the Meq gene showed that the isolate (SD121201) and Chinese reference strains, which are very virulent MDVs, are in the same clade. It was concluded that the Silkies tested were infected with MDV serotype 1. The Marek's disease epidemic has been controlled using CVI988/Rispens vaccines.
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PMID:Skin involvement in lymphomas caused by Marek's disease virus infection in Silkie chickens. 2458 47

In the present study, avian hepatitis E virus (HEV) and serotype-1 strains of Marek's disease virus (MDV-1) were detected from a flock of 27-wk-old brown layer hens in China, accompanied by an average daily mortality of 0.44%. Postmortem examination of 25 sick hens and five apparently healthy hens selected randomly from the flock showed significant pathologic changes consistent with hepatitis-splenomegaly syndrome (HSS), including hepatomegaly, peritoneal fluid, and hepatic subcapsular hemorrhages. Microscopic examination of these livers showed multifocal necrotizing hepatitis and mild lymphocytic infiltration. These liver samples were investigated for HEV by reverse-transcription PCR. The overall detection rate of HEV RNA in samples of sick chickens was about 56% (14/25), while in samples from apparently healthy hens, it was 80% (4/5). Sequencing analysis of three 242-base-pair fragments of the helicase gene revealed 95.5% to 97.9% nucleotide identity compared with published avian HEV genotype 3, whereas identities demonstrated only 77.3% to 86.0% similarity when compared with genotypes 1, 2, and 4. Unexpectedly, the MDV meq gene was detected in livers from both apparently healthy chickens (2/5) and sick chickens (12/25) by PCR analysis. The meq gene (396 base pairs) was determined to belong to MDV-1 by further sequencing. The co-infection rate of avian HEV and MDV in this flock was 30% (9/30). This is the first report of dual infection of a nonenvelope RNA virus (HEV) with a herpesvirus (MDV) in chickens in China.
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PMID:Natural Infection with Avian Hepatitis E Virus and Marek's Disease Virus in Brown Layer Chickens in China. 2761 Jul 34

1. There is no current data about the genotypes of Marek's disease virus (MDV) in Turkish poultry flocks; hence, this study was performed to analyse CVI988/Rispens, turkey herpesvirus (HVT) vaccine viruses and MDV field viruses as well as to perform phylogenetic analysis of MDV in Turkish layer chickens. 2. In 2017 and 2018, a total of 602 spleen samples from 49 layer flocks were collected from the Marmara, West Black Sea and Aegean regions. DNA was extracted from the spleen samples and the samples were analysed by real-time PCR probe assay to detect CVI988/Rispens and HVT vaccine viruses and MDV field strains. Samples found positive for MDV by real-time PCR were subjected to PCR using the Meq gene primers for phylogenetic analysis. 3. Amongst 49 flocks, virulent MDV was detected in nine flocks. CVI988/Rispens and HVT vaccine strains were detected in 47 flocks and HVT in all 49 flocks. Splenomegaly, hepatomegaly and tumours in the oviduct were observed in chickens of affected flocks. Virulent MDV was detected in 120 out of 602 spleen samples. Sequencing and phylogenetic analyses showed that MDVs detected in this study were closely related to MDV strains from Italy, Poland, Saudi Arabia, Iraq, India and China but showed diversity with MDV strains from Egypt and Hungary. Multiple sequence analysis of the Meq protein revealed several point mutations in deduced amino acid sequences. Interestingly, CVI988/Rispens vaccine virus from China (AF493555) showed mutations at position 66 (G66R) and 71 (S66A) along with two other vaccine strains from China (GU354326.1) and Russia (EU032468.1), in comparison with the other vaccine strain CVI988/Rispens (DQ534538). The molecular analyses of the Meq gene suggested that Turkish field strains of MDV are in the class of virulent or very virulent pathotypes. 4. The results have shown that MDV still affects poultry health, and the phylogenetic and amino acid variation data obtained will help in vaccination and control strategies.
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PMID:Molecular characterisation and phylogenetic analysis of Marek's disease virus in Turkish layer chickens. 3231 60

In two independent submissions, a 3-yr-old, dead Bourbon Red turkey tom from a zoo and a Royal Palm turkey hen from a backyard flock were submitted for necropsy. Both birds had been kept together with chickens. Findings of the necropsy of the first turkey were an enlarged and dark liver with many pale white foci and a few small white nodules, pale and enlarged spleen, prominent thymus, mottled and pale kidneys, and pale and enlarged testes. Findings of the necropsy of the second turkey were a dark and mildly enlarged liver and severely enlarged, firm, and pale kidneys. Histopathology revealed infiltration of most organs of both birds with neoplastic lymphocytes, which were uniform in the first turkey and pleomorphic in the second turkey. Immunohistochemistry with a CD3 marker identified the neoplastic lymphocytes as T cells. Marek's disease virus serotype 1 was detected with PCR in the livers of both birds, whereas PCRs for reticuloendotheliosis virus and lymphoproliferative disease virus were negative. Based on these findings, Marek's disease was diagnosed in both turkeys, which is very rare and were the first definitive cases reported in the United States. It is likely that the chickens were the source of infection.
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PMID:Two Cases of Marek's Disease in Backyard Turkeys. 3320 83