1/24. Virus-cell interaction in oligodendroglia, astroglia and phagocyte in progressive multifocal leukoencephalopathy. An electron microscopic study.A 46-year-old female, with an 11 year history of malignant lymphoreticular disease, developed a neurological illness clinically manifested by a focal mass lesion in the left frontal lobe. In biopsied tissue, immunofluorescence study revealed the presence of JC antigen in the glial cells. Histologically, the lesion was characteristic of PML consisting of PML consisting of focal necrosis in the subcortical white matter, numerous fat laden macrophages and marked hypertrophy of oligodendrocytes and astrocytes. By electron microscopy, hypertrophic astrocytes contained intranuclear viral particles consistent with papova virions and aggregates of intracytoplasmic viral particles consisting of a single to several virions tightly surrounded by a single membrane. The membrane appeared to have been derived from that of the cellular vesicles. Fusion of the virus-associated membrane to the astroglial plasmalemma occurred when the virions appeared to shift towards extracellular space. The virioncontaining astrocytes showed cytoplasmic "fibrillar hypertrophy" similar to the characteristic gigantic astroglias of PML. This fact would provide an additional evidence that these gigantic cells, although lacking identifiable viral structures, were the result of anaplastic transformation by jc virus. Many virus-bearing astroglias were noted to be in the early stage of cellular necrosis, of "edematous degeneration". This further indicates that the jc virus is capable of inducing both lytic and abortive astroglial infections. Many oligodendroglias were hypertrophic due to the presence of intranuclear viral particles and markedly increased numbers of microtubules and free ribosomes in the cytoplasm. Membrane-bound intracytoplasmic viral particles were also noted in the oligodendroglias. Some fat laden macrophages contained large intracytoplasmic viral bodies, presumably originating from phagocytized virus-bearing cells.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/24. Human herpesvirus 6-meningoencephalitis in an HIV patient with progressive multifocal leukoencephalopathy.Human herpesvirus 6 (HHV6) has been reported as a rare cause of meningoencephalitis and leukoencephalitis. We present an HIV-infected patient with lesions of progressive multifocal leukoencephalopathy (PML), but also meningoencephalitis apparently due to HHV6. immunohistochemistry for HHV6 antigens and in situ polymerase chain reaction for HHV6 genome showed many positive lymphocytes and microglia in the meningeal and cortical lesions. More importantly, dead and dying neurons were conspicuous; some were undergoing neuronophagia and some displayed evidence of HHV6 infection. A pathogenic role for this almost universal, and usually commensal, virus in inflammatory brain lesions and PML is briefly discussed.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/24. Infection with jc virus and possible dysplastic ganglion-like transformation of the cerebral cortical neurons in a case of progressive multifocal leukoencephalopathy.Infection of the cerebral cortical neurons with jc virus (JCV) with possible dysplastic ganglion-like alteration of the infected neurons found in a case of progressive multifocal leukoencephalopathy (PML) is described. The patient was a 21-year-old man with common variable immunodeficiency who died of PML after a 9-month clinical course. At autopsy, the white matter of the cerebrum, brainstem, cerebellum, and spinal cord exhibited extensive demyelination and necrosis. Numerous inclusion-bearing oligodendrocytes and bizarre astrocytes were found. In the occipital and temporal cortex, thick band-like aggregates of dysplastic ganglion-like cells (DGLCs) were found. These DGLCs showed immunohistochemical properties of neurons, and nuclei of some DGLCs were immunoreactive for large T antigen of SV40/JCV and p53, but not for capsid protein JCV VP1. in situ hybridization for mRNA of JCV large T antigen revealed positive signals in the nuclei of some DGLCs. These results indicate that JCV infected neurons and it is suggested that binding of the large T antigen with cellular proteins could have resulted in the dysplastic, ganglion cell-like change of the infected neurons, although the possibility that the aggregates of DGLCs represent a pre-existent malformative lesion of the cortex cannot be excluded completely.- - - - - - - - - - ranking = 3keywords = antigen (Clic here for more details about this article) |
4/24. Concomitant progressive multifocal leucoencephalopathy and primary central nervous system lymphoma expressing jc virus oncogenic protein, large T antigen.This report describes the concomitant occurrence of the jc virus (JCV) induced demyelinating disease progressive multifocal leucoencephalopathy (PML) and a primary central nervous system lymphoma (PCNS-L) in a patient with AIDS. Postmortem neuropathological examination revealed characteristic features of PML including multiple lesions of demyelination, enlarged oligodendrocytes with hyperchromatic nuclei (many containing eosinophilic intranuclear inclusions), and enlarged astrocytes with bizarre hyperchromatic nuclei. Immunohistochemical analysis demonstrated the expression of the JCV capsid protein VP-1 in the nuclei of infected oligodendrocytes and astrocytes. The PCNS-L lesion located in the basal ganglia was highly cellular, distributed perivascularly, and consisted of large atypical plasmacytoid lymphocytes. Immunohistochemical examination of this neoplasm identified it to be of B cell origin. Moreover, expression of the JCV oncogenic protein, T antigen, was detected in the nuclei of the neoplastic lymphocytes. This study provides the first evidence for a possible association between JCV and PCNS-L.- - - - - - - - - - ranking = 5keywords = antigen (Clic here for more details about this article) |
5/24. autopsy case of the cerebellar form of progressive multifocal leukoencephalopathy without immunodeficiency.A case of the cerebellar form of progressive multifocal leukoencephalopathy (PML) without remarkable immune depression or immune deficiency is reported here. The patient was a 74-year-old-woman who had complications of chronic renal failure and renal anemia for several years. Seven months before her death she had symptoms of general fatigue, gait disturbance and articulation disorder. During her hospitalization period her neurological disorder gradually progressed irreversibly with failure of consciousness and she died of respiratory failure. She did not have remarkable clinical signs of immunodeficiency nor did she receive immunosuppressive therapy. Clinically she had not been diagnosed with PML. At the post-mortem examination different degrees of demyelination were observed in the brain white matter: diffuse and severe in the cerebellum, moderate and coalescent in the brainstem, and light and patchy in the cerebrum. jc virus antigen-positive cells were frequently observed in the demyelinated lesions in the cerebrum and sometimes observed in the brainstem, but were rarely found in the cerebellum. These findings suggest that PML lesions may be present with different degrees of demyelination that are inversely correlated with the number of jc virus-infected cells. This fact should be considered when evaluating the brain biopsies of PML patients.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/24. Detection of jc virus type 1 in peripheral lymphocytes, brain and cerebrospinal fluid from two Korean AIDS patients with progressive multifocal leukoencephalopathy.The human polyomavirus jc virus (JCV) is the etiologic agent of the fatal demyelinating central nervous system disease progressive multifocal leukoencephalopathy (PML), which occurs in 4-7% of AIDS patients. Two Korean AIDS patients with PML were assayed for JCV, and the virus was genotyped by polymerase chain reaction, dna sequencing and phylogenetic analysis. Using immunohistochemical analysis, we also examined the distribution of JCV antigen in the brains of the patients. The JCV genome was detected in peripheral lymphocytes, brain and cerebrospinal fluid from these Korean PML patients. Although type 2 is the most common genotype in asia, the genotype of the JCV in these two AIDS patients was characterized as type 1, which is of European origin. We found that JCV antigen was selectively detected in oligodendrocytes and astrocytes of the brains from these patients. Compared to the prototype type 1 (Mad-1), two different nucleotides (G-->C) in the KOR-1 strain identified here were found at positions 2488 and 2490 of the major capsid protein VP1 gene. In summary, this is the first report of PML in Korean AIDS patients; it is also the first isolation of JCV type 1 in PML in East Asians.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
7/24. Fatal immune restoration disease in human immunodeficiency virus type 1-infected patients with progressive multifocal leukoencephalopathy: impact of antiretroviral therapy-associated immune reconstitution.Immune reconstitution resulting from use of highly active antiretroviral therapy in patients infected with human immunodeficiency virus type 1 (hiv-1) has been associated with a significant decrease in infectious morbidity and with improved survival. Occasionally, patients with quiescent disease due to human cytomegalovirus or nontuberculous mycobacteria may experience paradoxical worsening due to "dysregulated" restitution of the immune system (that is, immune restoration disease [IRD]). acquired immunodeficiency syndrome-related progressive multifocal leukoencephalopathy (PML) is uncommon and often improves with immune recovery. We describe 2 hiv-1-infected patients with PML that presented with paradoxical worsening after the patients had commenced active antiretroviral therapy. After they had a transient response to high-dose corticosteroid therapy, both patients died of progressive neurological deterioration. IRD in these patients with PML was unexpected and occurred soon after they had started receiving active antiretroviral therapy, during the period of improved antigen-specific T-helper cell function. Predictors of patients' proclivity for these adverse events are uncertain. Evaluation of targeted immunomodulatory therapy directed towards disease-specific IRD is critical and may play an important role in improved survival for patients who are at risk.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
8/24. Multifocal vacuolar leucoencephalopathy: a distinct HIV-associated lesion of the brain.A 20-year-old male AIDS patient developed rapidly progressive dementia for more than 3 months prior to death. autopsy showed, in addition to adrenal cytomegalovirus (CMV) infection and focal cerebral necrosis due to toxoplasmosis, multifocal subcortical white matter lesions of the brain which were strikingly similar to the histopathology of vacuolar myelopathy in AIDS. These distinct lesions contained macrophages which were rarely multinucleated and expressed HIV antigens by immunocytochemistry. The distribution of lesions mimics extrapontine myelinolysis and progressive multifocal leucoencephalopathy (PML); PML was excluded by the absence of papovaviruses by immunocytochemistry and by in situ dna hybridization. Tissue damage in multifocal vacuolar leucoencephalopathy is different from hitherto characterized HIV-specific neuropathology such as HIV encephalitis and HIV leucoencephalopathy, and should be included in the list of conditions with damage of the brain white matter in AIDS.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
9/24. Neoplastic angioendotheliomatosis (NAE) of the CNS in a patient with AIDS subacute encephalitis, diffuse leukoencephalopathy and meningo-cerebral cryptococcosis.A 12-year-old, hemophilic boy died with acquired immune deficiency syndrome (AIDS) after a clinical course characterized by progressive psycho-organic syndrome and opportunistic infections. Postmortem neuropathological examination revealed a cerebral form of neoplastic angioendotheliomatosis (NAE), leukoencephalopathy, giant cell encephalitis and meningo-cerebral cryptococcosis. The most unusual finding was the presence of proliferated neoplastic cells within lumina of some blood vessels throughout the central nervous system (CNS). These cells displayed cytologic features of malignancy and stained positively for common leukocyte antigen. Coronal sections showed diffuse cerebral and cerebellar leukoencephalopathy with most pronounced loss of myelin and axons in deep white matter, while the subcortical arcuate fibers and the corpus callosum were partially spared. In these areas numerous small foci of severe myelin loss were present. Microglial nodules and distinctive multinucleated giant cells (MGC) were numerous. Intracytoplasmic and intranuclear acidophilic inclusions were found in a few multinuclear and mononuclear cells. Close contact between mononuclear and multinuclear cells suggesting their fusion was also observed. As far as we know this is the first case of NAE encountered in AIDS, one of the rare primary cerebral forms and the youngest reported case of NAE up to now. This case could be considered as one proof more that NAE is a special form of malignant lymphoma.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
10/24. Human immunodeficiency virus (HIV) and jc virus in acquired immune deficiency syndrome (AIDS) patients with progressive multifocal leukoencephalopathy.Of the 93 acquired immune deficiency syndrome (AIDS) patients autopsied between 1983 and 1986, 27 had evidence of viral encephalitis of which 3 had progressive multifocal leukoencephalopathy (PML), confirmed by electron microscopy. Using in situ hybridization with biotinylated jc virus probes, paraffin sections from the brains of these 27 patients were examined. jc virus was found only in those patients with histologically proven PML, while no evidence of jc virus was detected in the brains of the other 24 AIDS patients despite the presence of white matter pathology. brain biopsies of the PML patients demonstrated human immunodeficiency virus (HIV)-infected macrophages infiltrating regions of demyelination. When the patients died (2 to 6 months after diagnosis of PML), many more macrophages contained hiv antigens and some had fused to form multinucleated giant cells. These findings suggest that in AIDS patients, papovaviruses not only cause damage by directly infecting oligodendroglia but causes additional damage by eliciting the ingress of macrophages latently infected with HIV. As was seen with other infections (e.g., cytomegalovirus) of the CNS this might be a general mechanism of HIV entry into the brain.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
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