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Biomedical subjects

D H Gilden

Publications and source records attributed to D H Gilden.

At least 37 records · Page 2Linked to original sources
PubMed2001

An animal model of varicella virus infection.

Varicella-zoster virus (VZV) causes chickenpox in children; establishes latency in cranial nerve, dorsal root, and autonomic ganglia; and reactivates decades later to produce zoster. VZV produces disease only in humans. Although attempts to produce disease and study VZV latency in experimentally infected animals have resulted in virus in trigeminal or dorsal root ganglia, no clinical signs of infection or reactivation developed. In contrast, simian varicella virus (SVV) produces a naturally occurring exanthematous disease in non-human primates that mimics human varicella. Experimental inoculation of non-human primates causes similar, if not identical, clinical and pathological changes observed in monkeys naturally infected with SVV. Like VZV, SVV becomes latent in ganglia and reactivates, often with entire body rash. SVV and VZV encode antigenically related polypeptides. Both virus genomes have been sequenced and shown to be colinear, sharing up to 75% DNA homology. During latency, an SVV homolog of one of the five VZV genes transcribed in latently infected human ganglia has been detected in monkey ganglia. Preliminary studies in which monkeys were inoculated intratracheally with SVV revealed the presence of viral DNA and RNA in multiple tissues, including blood mononuclear cells, months after experimental infection. These findings differed from the expected restricted localization of the virus DNA to ganglia only and the expected limited viral gene expression, and probably reflect the high virus load delivered intratracheally compared to natural SVV infection in monkeys. Nevertheless, clinical, pathological, and molecular similarities between SVV and VZV indicate that SVV infection in non-human primates has considerable potential as an animal model for human varicella.

Animals↗
PubMed2001

Ramsay Hunt syndrome.

The strict definition of the Ramsay Hunt syndrome is peripheral facial nerve palsy accompanied by an erythematous vesicular rash on the ear (zoster oticus) or in the mouth. J Ramsay Hunt, who described various clinical presentations of facial paralysis and rash, also recognised other frequent symptoms and signs such as tinnitus, hearing loss, nausea, vomiting, vertigo, and nystagmus. He explained these eighth nerve features by the close proximity of the geniculate ganglion to the vestibulocochlear nerve within the bony facial canal. Hunt's analysis of clinical variations of the syndrome now bearing his name led to his recognition of the general somatic sensory function of the facial nerve and his defining of the geniculate zone of the ear. It is now known that varicella zoster virus (VZV) causes Ramsay Hunt syndrome. Compared with Bell's palsy (facial paralysis without rash), patients with Ramsay Hunt syndrome often have more severe paralysis at onset and are less likely to recover completely. Studies suggest that treatment with prednisone and acyclovir may improve outcome, although a prospective randomised treatment trial remains to be undertaken. In the only prospective study of patients with Ramsay Hunt syndrome, 14% developed vesicles after the onset of facial weakness. Thus, Ramsay Hunt syndrome may initially be indistinguishable from Bell's palsy. Further, Bell's palsy is significantly associated with herpes simplex virus (HSV) infection. In the light of the known safety and effectiveness of antiviral drugs against VZV or HSV, consideration should be given to early treatment of all patients with Ramsay Hunt syndrome or Bell's palsy with a 7-10 day course of famciclovir (500 mg, three times daily) or acyclovir (800 mg, five times daily), as well as oral prednisone (60 mg daily for 3-5 days). Finally, some patients develop peripheral facial paralysis without ear or mouth rash, associated with either a fourfold rise in antibody to VZV or the presence of VZV DNA in auricular skin, blood mononuclear cells, middle ear fluid, or saliva. This indicates that a proportion of patients with "Bell's palsy" have Ramsay Hunt syndrome zoster sine herpete. Treatment of these patients with acyclovir and prednisone within 7 days of onset has been shown to improve the outcome of recovery from facial palsy.

Bell Palsy↗
PubMed2001

Varicella-Zoster virus infections of the nervous system: clinical and pathologic correlates.

BACKGROUND: Diseases that present with protean manifestations are the diseases most likely to pose diagnostic challenges for both clinicians and pathologists. Among the most diverse disorders caused by a single known toxic, metabolic, neoplastic, or infectious agent are the central and peripheral nervous system complications of varicella-zoster virus (VZV). METHODS: The pathologic correlates of the neurologic complications of VZV infection, as well as current methods for detecting viral infections, are discussed and presented in pictorial format for the practicing pathologist. RESULTS: Varicella-zoster virus causes chickenpox (varicella), usually in childhood; most children manifest only mild neurologic sequelae. After chickenpox resolves, the virus becomes latent in neurons of cranial and spinal ganglia of nearly all individuals. In elderly and immunocompromised individuals, the virus may reactivate to produce shingles (zoster). After zoster resolves, many elderly patients experience postherpetic neuralgia. Uncommonly, VZV can spread to large cerebral arteries to cause a spectrum of large-vessel vascular damage, ranging from vasculopathy to vasculitis, with stroke. In immunocompromised individuals, especially those with cancer or acquired immunodeficiency syndrome, deeper tissue penetration of the virus may occur (as compared with immunocompetent individuals), with resultant myelitis, small-vessel vasculopathy, ventriculitis, and meningoencephalitis. Detection of the virus in neurons, oligodendrocytes, meningeal cells, ependymal cells, or the blood vessel wall often requires a combination of morphologic, immunohistochemical, in situ hybridization, and polymerase chain reaction (PCR) methods. The PCR analysis of cerebrospinal fluid remains the mainstay for diagnosing the neurologic complications of VZV during life. CONCLUSIONS: Varicella-zoster virus infects a wide variety of cell types in the central and peripheral nervous system, explaining the diversity of clinical disorders associated with the virus.

Adult↗
PubMed2000

Sequence analysis of the leftward end of simian varicella virus (EcoRI-I fragment) reveals the presence of an 8-bp repeat flanking the unique long segment and an 881-bp open-reading frame that is absent in the varicella zoster virus genome.

Simian varicella virus (SVV) causes varicella (chickenpox) in nonhuman primates, becomes latent in cranial and dorsal root ganglia, and reactivates to produce zoster (shingles). Because the clinical and molecular features of SVV closely resemble those of varicella zoster virus (VZV) infection of humans, SVV infection of primates has served as an experimental model of VZV pathogenesis and latency. The SVV genome has been completely mapped, but attempts to clone the 3600-bp EcoRI fragment located at the leftward end of the virus genome have hitherto been unsuccessful. Herein, we report the cloning and the complete nucleotide sequence of this region. Comparison of the SVV and VZV sequences in this region revealed an 8-bp inverted repeat sequence flanking the unique long segment of the SVV genome; an 879-bp open-reading frame (ORF) A in SVV that is absent in VZV but has 42% amino acid identity to SVV ORF 4 and 49% to VZV ORF 4; a 342-bp ORF B in SVV with 35% amino acid identity to a 387-bp ORF located to the left of ORF 1 on the VZV genome; and a 303-bp ORF in SVV with 27% amino acid identity to VZV ORF 1. No homologue of VZV ORF 2 was detected. Transcripts specific for ORFs A and B were present in SVV-infected cells in culture and in acutely infected monkey ganglia. Overall, there are more than 2000 bp of DNA in the SVV genome that are absent in the VZV genome.

Amino Acid Sequence↗
PubMed2000

Comparison of immunoglobulin G heavy-chain sequences in MS and SSPE brains reveals an antigen-driven response.

OBJECTIVE: To better understand B-cell activation in MS by analyzing the immunoglobulin (Ig)G heavy chain variable region (VH) repertoire found in MS brains and comparing it with brain VH sequences in individuals with subacute sclerosing panencephalitis (SSPE)--a chronic encephalitis produced by measles virus (MV)-and characterized by an antigen-driven oligoclonal IgG response to MV antigens. BACKGROUND: The specificity of oligoclonal IgG in MS CSF and plaques, and their relevance to the pathogenesis of MS is unknown. METHODS: Nested PCR was used to amplify and sequence the rearranged IgG heavy-chain VH repertoire in plaques of three acute MS brains and in three SSPE brains. A representative population of VH sequences from each tissue was aligned to the known 51 functional VH germline segments. From this the authors determined the closest VH family germline segment, and the degree and location of somatic mutations for each unique IgG. RESULTS: As expected for an antigen-driven response against MV antigens, most VH sequences from the SSPE brains were mutated extensively compared with their closest germline segments. Furthermore, SSPE VH sequences accumulated replacement mutations preferentially in the complementary-determining regions (CDRs) relative to framework regions-features normally observed during antigen-driven selection. A comparison of VH family and germline usage also demonstrated that each SSPE brain had its own unique IgG response. When the authors compared the VH response in MS plaques with SSPE, MS VH sequences were also mutated extensively, displayed a preferential accumulation of replacement mutations in CDRs, and were unique in each MS brain. CONCLUSION: The presence of an antigen-driven response in MS, rather than a nonconventional mechanism of B-cell activation, warrants additional analysis of the specificity of IgG in MS brain and CSF.

Adolescent↗
PubMed2000

Identification of simian varicella virus gene 21 promoter region using green fluorescent protein.

Clinical, pathological, immunological and virological features of simian varicella virus (SVV) infection in primates closely resemble those of varicella zoster virus (VZV) infection in humans. In ganglia infected latently of humans and monkeys, gene 21 of VZV and SVV is transcribed, respectively. We determined the nucleotide sequence of the intragenic region between SVV genes 20 and 21 to identify the putative promoter region for SVV gene 21. A recombinant clone was prepared in which the gene encoding green fluorescent protein (GFP) was inserted ten base pairs upstream of the predicted translational start site for SVV gene 21. SVV-infected monkey kidney cells transfected with the recombinant clone showed the presence of green fluorescence, whereas transfection of these cells with a construct containing the GFP gene in the opposite orientation, produced no fluorescence. The recombinant clone containing GFP flanked by SVV sequences can be used to prepare a SVV mutant in which the virus gene 21 promoter drives GFP. Such a mutant will be useful in analyzing varicella pathogenesis and latency in experimentally infected animals, studies not possible in humans.

Animals↗
PubMed2000

Numbers of neurons and non-neuronal cells in human trigeminal ganglia.

We analyzed both trigeminal ganglia of eight post-mortem human subjects for their content of neurons and non-neuronal cells using dissociated cell suspension techniques. Neuronal counts in each of the 16 ganglia ranged from 20,000 to 35,400, with an average of 27,400 +/- 4800, and the estimated ratio of non-neuronal to neuronal cells was 100 to 1. Our numbers are comparable to the lower ranges obtained using different techniques in previous studies.

Adult↗
PubMed2000

Analysis of individual human trigeminal ganglia for latent herpes simplex virus type 1 and varicella-zoster virus nucleic acids using real-time PCR.

Herpes simplex virus type 1 (HSV-1) and varicella-zoster virus (VZV) establish latent infections in the peripheral nervous system following primary infection. During latency both virus genomes exhibit limited transcription, with the HSV-1 LATs and at least four VZV transcripts consistently detected in latently infected human ganglia. In this study we used real-time PCR quantitation to determine the viral DNA copy number in individual trigeminal ganglia (TG) from 17 subjects. The number of HSV-1 genomes was not significantly different between the left and right TG from the same individual and varied per subject from 42.9 to 677.9 copies per 100 ng of DNA. The number of VZV genomes was also not significantly different between left and right TG from the same individual and varied per subject from 37.0 to 3,560.5 copies per 100 ng of DNA. HSV-1 LAT transcripts were consistently detected in ganglia containing latent HSV-1 and varied in relative expression by >500-fold. Of the three VZV transcripts analyzed, only transcripts mapping to gene 63 were consistently detected in latently infected ganglia and varied in relative expression by >2,000-fold. Thus, it appears that, similar to LAT transcription in HSV-1 latently infected ganglia, VZV gene 63 transcription is a hallmark of VZV latency.

Aged↗
PubMed2000

Cloning the antibody response in humans with chronic inflammatory disease: immunopanning of subacute sclerosing panencephalitis (SSPE) brain sections with antibody phage libraries prepared from SSPE brain enriches for antibody recognizing measles virus antigens in situ.

In central nervous system (CNS) infectious and inflammatory diseases of known cause, oligoclonal bands represent antibody directed against the causative agent. To determine whether disease-relevant antibodies can be cloned from diseased brain, we prepared an antibody phage display library from the brain of a human with subacute sclerosing panencephalitis (SSPE), a chronic encephalitis caused by measles virus, and selected the library against SSPE brain sections. Antibodies that were retrieved reacted strongly with measles virus cell extracts by enzyme-linked immunosorbent assay and were specific for the measles virus nucleocapsid protein. These antibodies immunostained cells in different SSPE brains but not in control brain. Our data provide the first demonstration that diseased brain can be used to select in situ for antibodies directed against the causative agent of disease and point to the potential usefulness of this approach in identifying relevant antibodies in chronic CNS or systemic inflammatory diseases of unknown cause.

Antibodies, Viral↗
PubMed1999

Cloning the antibody response in humans with inflammatory central nervous system disease: analysis of the expressed IgG repertoire in subacute sclerosing panencephalitis brain reveals disease-relevant antibodies that recognize specific measles virus antigens.

The presence of increased IgG in the brains of humans with infectious and inflammatory CNS diseases of unknown etiology such as multiple sclerosis may be a clue to the cause of disease. For example, the intrathecally synthesized oligoclonal bands (OGBs) in diseases such as subacute sclerosing panencephalitis (SSPE) or cryptococcal meningitis have been shown to represent Ab directed against the causative agents, measles virus (MV) or Cryptococcus neoformans, respectively. Using SSPE as a model system, we have developed a PCR-based strategy to analyze the repertoire of IgG V region sequences expressed in SSPE brain. We observed abnormal expression of germline V segments, overrepresentation of particular sequences that correspond to the oligoclonal bands, and substantial somatic mutation of most clones from the germline, which, taken together, constitute features of Ag-driven selection in the IgG response. Using the most abundant or most highly mutated gamma H chain and kappa or lambda L chain sequences in various combinations, we constructed functional Abs in IgG mammalian expression vectors. Three Abs specifically stained MV-infected cells. One Ab also stained cells transfected with the MV nucleoprotein, and a second Ab stained cells transfected with the MV-fusion protein. This technique demonstrates that functional Abs produced from putative disease-relevant IgG sequences can be used to recognize their corresponding Ags.

Amino Acid Sequence↗
PubMed1999

Cloning the antibody response in humans with inflammatory CNS disease: isolation of measles virus-specific antibodies from phage display libraries of a subacute sclerosing panencephalitis brain.

We have developed a strategy to identify the disease-relevant antigens in a chronic inflammatory CNS disease exhibiting intrathecally expressed oligoclonal IgG. Using subacute sclerosing panencephalitis (SSPE), a chronic inflammatory measles virus infection of the brain as a model system, we constructed a phage display antibody Fab library from the amplified products of IgG expressed in the brain. Selection of the library against measles virus-infected cell lysates yielded four distinct Fabs which, by ELISA and by immunostaining, reacted specifically with measles virus-infected cells. Three Fabs immunoprecipitated a 72 kDa protein from infected cell cultures corresponding to the measles virus phosphoprotein. The fourth Fab immunoprecipitated and recognized by immunoblotting a 60 kDa protein corresponding to the measles virus nucleoprotein. The results demonstrate that functional antibodies from an inflammatory CNS disease can be expressed in bacteria and used to identify disease-relevant antigens. This approach could be applied to chronic inflammatory CNS diseases of unknown cause such as multiple sclerosis.

Adolescent↗
PubMed1999

Subacute painful lumbosacral polyradiculoneuropathy in immunocompromised patients.

The syndrome of inflammatory subacute lumbosacral polyradiculoneuropathy (SLP) has been reported in acquired immunodeficiency syndrome (AIDS) patients in association with cytomegalovirus infection and is only partially amenable to anti-viral therapy. We report three cases of relatively benign inflammatory painful SLP in two non-AIDS, immunosuppressed patients and one who HIV-seroconversed at the time of clinical presentation. SLP developed: (1) in association with HIV seroconversion; (2) during ECHO virus infection in a patient with common variable immune deficiency; and (3) after a severe systemic infection that induced transient immunosuppression due to Epstein-Barr virus reactivation. This report expands the spectrum of viruses associated with acute and subacute lumbosacral polyradiculoneuropathy and may shed light on its possible pathogenesis.

Adult↗
PubMed1999

Prevalence of varicella-zoster virus DNA in dissociated human trigeminal ganglion neurons and nonneuronal cells.

Previous analyses using in situ hybridization alone or together with PCR have yielded conflicting results regarding the cell type in which latent varicella-zoster virus (VZV) resides. We separated human trigeminal ganglia (TG) into neuronal and nonneuronal fractions, followed by primary and nested PCR to quantitate VZV DNA at the single cell level. Both TG from each of eight cadavers were dissociated and separated into neuronal and nonneuronal cell suspensions by differential filtration. Analysis of the neuron fraction (5,000 neurons per sample) revealed VZV DNA in 9 of 16 samples, with copy numbers ranging from 1 to 12, whereas only 2 of 16 nonneuronal cell samples were positive for VZV DNA, with 1 copy each. Further analysis of 10 samples of 100 neurons and the corresponding nonneuronal cell fractions from each TG of a single subject revealed VZV DNA in 3 of 10 samples of the left TG (range, 2 to 5 copies) and in 1 of 10 samples of the right TG (2 copies) but in none of the 20 nonneuronal cell fractions. These data indicate that latent VZV DNA is present primarily, if not exclusively, in neurons, at a frequency of two to five copies per latently infected neuron.

Aged↗
PubMed1998

The value of cerebrospinal fluid antiviral antibody in the diagnosis of neurologic disease produced by varicella zoster virus.

We studied four patients with subacute to chronic varicella zoster virus (VZV) infection of the central nervous system (CNS). VZV infection was verified by detecting antibody to VZV in the cerebrospinal fluid (CSF). VZV caused myelitis in two patients and encephalitis in two patients. In one of the patients with VZV encephalitis, in addition to VZV IgM antibody, VZV DNA was found in the CSF. Among the four patients with VZV infection of the CNS, CSF antibody to VZV was the crucial diagnostic laboratory test which corroborated the clinical features, and indicated that VZV caused neurologic disease. In addition to looking for amplifiable VZV DNA in the CSF of patients with neurologic disease whose clinical and radiologic features suggest VZV infection, we also recommend a search for CSF antibody to VZV, particularly in patients with intervals of weeks to months between zoster and the onset of neurologic disease, or in those patients without rash in whom the tempo of illness is unknown.

AIDS-Related Opportunistic Infections↗