Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0206061 (interstitial pneumonia)
 6,105 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Viral load may be an important indicator of disease progression in sheep infected with maedi-visna virus (MVV). To assess this variable accurately in MVV-infected sheep, a quantitative competitive-polymerase chain reaction (QC-PCR) was developed. A conserved region of the MVV pol gene was selected. The RT-PCR MVV pol product was cloned and mutagenised in vitro by PCR to produce a competitor template reduced in length from 217 to 192 bp, but which retained the original flanking MVV pol PCR primers. The competitor template was quantified accurately and in an optimised QC-PCR protocol serial dilutions of this template were co-amplified with known amounts of sample DNA. MVV DNA levels in peripheral blood monocytes and alveolar macrophages from MVV-infected sheep (n=12) were assessed by QC-PCR. Viral DNA load in alveolar macrophages was significantly higher than that in peripheral blood monocytes when the animals were compared overall. A comparison was also made between alveolar macrophages from the lungs of seropositive animals with or without histopathological evidence of pulmonary lesions. The load of MVV DNA in alveolar macrophages was low in sheep without histopathological evidence of lesions in the lung. In contrast, in alveolar macrophages from sheep with histopathological lesions in the lung, there was a significantly higher level of MVV DNA. The correlation of MVV load with pulmonary lesions suggests that infected alveolar macrophages play a key role in the pathogenesis of this lymphoid interstitial pneumonia.
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PMID:Quantitative analysis of maedi-visna virus DNA load in peripheral blood monocytes and alveolar macrophages. 1071 71

We report, to our knowledge, the first HIV type 1 (HIV-1) transgenic (Tg) rat. Expression of the transgene, consisting of an HIV-1 provirus with a functional deletion of gag and pol, is regulated by the viral long terminal repeat. Spliced and unspliced viral transcripts were expressed in lymph nodes, thymus, liver, kidney, and spleen, suggesting that Tat and Rev are functional. Viral proteins were identified in spleen tissue sections by immunohistochemistry and gp120 was present in splenic macrophages, T and B cells, and in serum. Clinical signs included wasting, mild to severe skin lesions, opaque cataracts, neurological signs, and respiratory difficulty. Histopathology included a selective loss of splenocytes within the periarterial lymphoid sheath, increased apoptosis of endothelial cells and splenocytes, follicular hyperplasia of the spleen, lymphocyte depletion of mesenteric lymph nodes, interstitial pneumonia, psoriatic skin lesions, and neurological, cardiac, and renal pathologies. Immunologically, delayed-type hypersensitivity response to keyhole limpet hemocyanin was diminished. By contrast, Ab titers and proliferative response to recall antigen (keyhole limpet hemocyanin) were normal. The HIV-1 Tg rat thus has many similarities to humans infected with HIV-1 in expression of viral genes, immune-response alterations, and pathologies resulting from infection. The HIV-1 Tg rat may provide a valuable model for some of the pathogenic manifestations of chronic HIV-1 diseases and could be useful in testing therapeutic regimens targeted to stages of viral replication subsequent to proviral integration.
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PMID:An HIV-1 transgenic rat that develops HIV-related pathology and immunologic dysfunction. 1148 87

Maedi-visna is a slow virus infection of sheep leading to a progressing lymphoproliferative disease which is invariably fatal. It affects multiple organs, but primarily the lungs where it causes interstitial pneumonia (maedi). Infection of the central nervous system was commonly observed in Icelandic sheep (visna), infection of mammary glands (hard udder) in sheep in Europe and the USA, and infection of the joints in sheep in the USA. The name ovine progressive pneumonia (OPP) is commonly used in the USA and ovine lentivirus (OvLV) infection is also a name used for maedi-visna. A related infection of goats, caprine arthritis-encephalitis (CAE), is common in Europe and the USA. The natural transmission of maedi-visna is mostly by the respiratory route, but also to newborn lambs by colostrum and milk. Intrauterine transmission seems to be rare and venereal transmission is not well documented. Macrophages are the major target cells of maedi-visna virus (MVV), but viral replication is greatly restricted in the animal host, apparently due to a posttranscriptional block. The low-grade viral production in infected tissues can explain the slow course of the disease in sheep. The lesions in maedi-visna consist of infiltrates of lymphocytes, plasma cells, and macrophages, and are detectable shortly after experimental transmission. Several studies indicate that the lesions are immune mediated and that cytotoxic T-lymphocytes may be important effector cells. The persistence of the MVV infection is explained by a reservoir of latently infected blood and bone marrow monocytes, which migrate into the target organs and mature into macrophages with proviral DNA transcription, but limited replication of virus. The MVV particles are morphologically similar to those of other retroviruses and the mode of replication follows the same general pattern. The genome organization and gene regulation resembles that of other lentiviruses. In addition to gag, pol and env, MVV has three auxiliary genes (tat, rev and vif), which seem to have similar functions as in other lentiviruses, with a possible exception of the tat gene. A determination of the 9200 nucleotide sequence of the MVV genome shows a close relationship to CAE virus, but limited sequence homology with other lentiviruses, and only in certain conserved domains of the reverse transcriptase and possibly in the surface protein. MVV infection in sheep and HIV-1 infection in humans have a number of features in common such as a long preclinical period following transmission, and a slow development of multiorgan disease with fatal outcome. A brief early acute phase, which is terminated by the immune response, is also an interesting common feature. Like HIV-1, MVV is macrophage tropic and the early stages of the HIV-1 infection which affect the central nervous system and the lungs are in many ways comparable to maedi-visna. In contrast to HIV-1, MVV does not infect T-lymphocytes and does not cause T-cell depletion and immunodeficiency. This is responsible for the difference in the late stages of the HIV-1 and MVV infections and the final clinical outcome. Despite limited sequence homology, certain proteins of MVV and HIV-1 show structural and functional similarities. Studies of MVV may therefore help in the search for new drugs against lentiviruses, including HIV-1.
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PMID:Maedi-visna virus and its relationship to human immunodeficiency virus. 1642 63