Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 63
Filter
1.
Neuropathol Appl Neurobiol ; 38(2): 175-200, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21883374

ABSTRACT

AIMS: Combined anti-retroviral therapy (cART) has led to a reduction in the incidence of HIV-associated dementia (HAD), a severe motor/cognitive disorder afflicting HIV(+) patients. However, the prevalence of subtler forms of neurocognitive dysfunction, which together with HAD are termed HIV-associated neurocognitive disorders (HAND), continues to escalate in the post-cART era. The microgliosis, astrogliosis, dendritic damage, and synaptic and neuronal loss observed in autopsy cases suggest an underlying neuroinflammatory process, due to the neurotoxic factors released by HIV-infected/activated macrophages/microglia in the brain, might underlie the pathogenesis of HAND in the post-cART era. These factors are known to induce the integrated stress response (ISR) in several neurodegenerative diseases; we have previously shown that BiP, an indicator of general ISR activation, is upregulated in cortical autopsy tissue from HIV-infected patients. The ISR is composed of three pathways, each with its own initiator protein: PERK, IRE1α and ATF6. METHODS: To further elucidate the specific ISR pathways activated in the central nervous system of HAND patients, we examined the protein levels of several ISR proteins, including ATF6, peIF2α and ATF4, in cortical tissue from HIV-infected patients. RESULTS: The ISR does not respond in an all-or-none fashion in HAND, but rather demonstrates a nuanced activation pattern. Specifically, our studies implicate the ATF6 pathway of the ISR as a more likely candidate than the PERK pathway for increases in BiP levels in astrocytes. CONCLUSION: These findings begin to characterize the nature of the ISR response in HAND and provide potential targets for therapeutic intervention in this disease.


Subject(s)
Astrocytes/metabolism , Brain/pathology , Cognition Disorders/complications , Cognition Disorders/metabolism , HIV Infections/complications , HIV Infections/metabolism , Neurons/metabolism , Activating Transcription Factor 4/metabolism , Activating Transcription Factor 6 , Adult , Basic-Leucine Zipper Transcription Factors/metabolism , Cognition Disorders/pathology , Endoribonucleases/metabolism , Eukaryotic Initiation Factor-2/metabolism , Female , HIV Infections/pathology , HSP70 Heat-Shock Proteins/metabolism , Humans , Male , Middle Aged , Protein Serine-Threonine Kinases/metabolism , Transcription Factor CHOP/metabolism
2.
Mol Cell Neurosci ; 47(2): 154-65, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21504794

ABSTRACT

HIV-Associated Neurocognitive Disorder (HAND) remains a serious complication of HIV infection, despite combined Anti-Retroviral Therapy (cART). Neuronal dysfunction and death are attributed to soluble factors released from activated and/or HIV-infected macrophages. Most of these factors affect the cell cycle machinery, determining cellular outcomes even in the absence of cell division. One of the earliest events in cell cycle activation is hyperphosphorylation of the retinoblastoma protein, pRb (ppRb). We and others have previously shown increased ppRb expression in the CNS of patients with HIV encephalitis (HIVE) and in neurons in an in vitro model of HIV-induced neurodegeneration. However, trophic factors also lead to an increase in neuronal ppRb with an absence of cell death, suggesting that, depending on the stimulus, hyperphosphorylation of pRb can have different outcomes on neuronal fate. pRb has multiple serines and threonines targeted for phosphorylation by distinct kinases, and we hypothesized that different stimuli may target separate sites for phosphorylation. Thus, to determine whether pRb is differentially phosphorylated in response to different stimuli and whether any of these sites is preferentially phosphorylated in association with HIV-induced neurotoxicity, we treated primary rat mixed cortical cultures with trophic factors, BDNF or RANTES, or with the neurotoxic factor, N-methyl-d-aspartate (NMDA), or with supernatants containing factors secreted by HIV-infected monocyte-derived macrophages (HIV-MDM), our in vitro model of HIV-induced neurodegeneration. We found that, while BDNF and RANTES phosphorylated serine807/811 and serine608 in vitro, treatment with HIV-MDM did not, even though these trophic factors are components of HIV-MDM. Rather, HIV-MDM targets a specific phosphorylation site, serine795, of pRb for phosphorylation in vitro and this ppRb isoform is also increased in HIV-infected brains in vivo. Further, overexpression of a nonphosphorylatable pRb (ppRb S795A) attenuated HIV-MDM-induced neurotoxicity. These findings indicate that HIV-infection in the brain is associated with site-specific hyperphosphorylation of pRb at serine795, which is not induced by other tested stimuli, and that this phosphorylation contributes to neuronal death in this disease, demonstrating that specific pRb sites are differentially targeted and may have diverse impacts on the viability of post-mitotic neurons.


Subject(s)
AIDS Dementia Complex/metabolism , HIV-1/metabolism , Retinoblastoma Protein/metabolism , Adult , Animals , Brain-Derived Neurotrophic Factor/metabolism , Cell Death/physiology , Cells, Cultured , Chemokine CCL5/metabolism , Cyclin-Dependent Kinase 5/metabolism , HIV Infections/complications , Humans , Intercellular Signaling Peptides and Proteins/metabolism , Macrophages/cytology , Macrophages/metabolism , Male , Middle Aged , Neuroglia/cytology , Neuroglia/metabolism , Neurons/cytology , Neurons/physiology , Phosphorylation , Rats , Rats, Sprague-Dawley , Serine/metabolism
3.
Neurology ; 69(13): 1314-21, 2007 Sep 25.
Article in English | MEDLINE | ID: mdl-17652642

ABSTRACT

BACKGROUND: Cognitive impairment continues to be a significant neurologic complication of HIV infection and has been associated with oxidative stress-induced neuronal injury. Selegiline is an MAO-B inhibitor with antioxidant and neurotrophic properties. This rationale has led to the design and implementation of this Selegiline Transdermal System (STS) study with the primary aims of assessing safety and tolerability of STS as well as improvement in cognitive performance. METHODS: HIV-1 infected individuals with impaired cognitive functioning were enrolled in this placebo-controlled, three-arm study of STS across 17 sites. Cognitive impairment was determined using a standard battery of neuropsychological tests. Subjects were randomized to receive STS 3 mg/24 hours, STS 6 mg/24 hours, or matching placebo patches daily. The primary efficacy endpoint was defined as the change in neuropsychological composite Z-score (NPZ-6) from baseline to week 24. Measures of safety included frequencies of adverse experiences and abnormal results on laboratory tests. RESULTS: A total of 128 subjects (88% men, 51% white) were enrolled, median age 45 years. Most subjects (62%) had mild to moderate AIDS dementia complex. The 24-week NPZ-6 median (interquartile range) changes were 0.22 (-0.28, 0.55) for the selegiline 3 mg/24 hours arm, 0.21 (-0.18, 0.62) for the selegiline 6 mg/24 hours arm, and 0.28 (-0.16, 0.64) for the placebo arm (a positive score indicates improvement from baseline) (p = 0.914). Severe laboratory abnormalities were few and occurred in similar proportion among the three treatment arms. CONCLUSION: Selegiline was safe and well tolerated by HIV-infected individuals with cognitive impairment and mild to moderate immune suppression; however, no cognitive or functional improvement was observed in this phase II study.


Subject(s)
AIDS Dementia Complex/drug therapy , Antioxidants/administration & dosage , Cytoprotection/drug effects , Neuroprotective Agents/administration & dosage , Selegiline/administration & dosage , AIDS Dementia Complex/diagnosis , AIDS Dementia Complex/psychology , Adult , Aged , Brain/drug effects , Brain/physiopathology , Brain/virology , Cytoprotection/physiology , Female , Humans , Male , Middle Aged , Nerve Degeneration/drug therapy , Nerve Degeneration/prevention & control , Nerve Degeneration/virology , Neuroprotective Agents/adverse effects , Neuropsychological Tests , Placebos , Selegiline/adverse effects , Treatment Failure
4.
Neurology ; 66(6): 862-6, 2006 Mar 28.
Article in English | MEDLINE | ID: mdl-16567703

ABSTRACT

OBJECTIVE: To evaluate the effects of HIV-associated neurocognitive impairment on caudate blood flow and volume. METHODS: The authors performed continuous arterial spin labeled MRI on 42 HIV+ patients (23 subsyndromic and 19 HIV neurosymptomatic) on highly active antiretroviral therapy and 17 seronegative controls. They compared caudate blood flow and volume among groups. RESULTS: A stepwise decrease in both caudate blood flow and volume was observed with increasing HIV-associated neurocognitive impairment. Compared with seronegative controls, baseline caudate blood flow was reduced in HIV+ neurosymptomatic patients (p = 0.001) with a similar decreasing trend for subsyndromic HIV+ patients (p = 0.070). Differences in caudate volume were observed only for neurosymptomatic HIV+ patients compared with controls (p = 0.010). A Jonckheere-Terpstra test for trends was significant for both caudate blood flow and volume for each of the three subgroups. Pearson product moment correlation coefficients were not significant between caudate blood flow and volume for each group. CONCLUSIONS: Decreasing trends in caudate blood flow and volume were associated with significantly increasing HIV-associated neurocognitive impairment (HNCI), with the greatest decreases observed for more severely impaired patients. However, reductions in caudate blood flow and volume were poorly correlated. Changes in residual caudate blood flow may act as a surrogate biomarker for classifying the degree of HNCI.


Subject(s)
AIDS Dementia Complex/physiopathology , Blood Volume/physiology , Caudate Nucleus/blood supply , HIV Infections/physiopathology , HIV-1 , AIDS Dementia Complex/psychology , Adult , Echo-Planar Imaging/methods , Female , HIV Infections/psychology , Humans , Male , Middle Aged , Neuropsychological Tests
5.
Neuroimage ; 23(4): 1336-47, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15589098

ABSTRACT

OBJECTIVE: Differences in diagnostic criteria and methods have led to mixed results regarding the metabolite pattern of HIV-associated brain injury in relation to neurocognitive impairment. Therefore, a multicenter MRS consortium was formed to evaluate the neurometabolites in HIV patients with or without cognitive impairment. METHODS: Proton magnetic resonance spectroscopy (MRS) at short-echo time (30 ms) was assessed in the frontal white matter, basal ganglia, and parietal cortex of 100 HIV patients [61 with AIDS dementia complex (ADC) and 39 neuroasymptomatic (NAS)] and 37 seronegative (SN) controls. RESULTS: Compared to SN, NAS had higher glial marker myoinositol-to-creatine ratio (MI/Cr) in the white matter (multivariate analyses, adjusted P=0.001), while ADC showed further increased MI/Cr in the white matter and basal ganglia (both P<0.001), and increased choline compounds (Cho)/Cr in white matter (P=0.04) and basal ganglia (P<0.001). Compared to NAS, ADC showed a reduction in the neuronal marker N-acetyl compound (NA)/Cr in the frontal white matter (P=0.007). CSF, but not plasma, viral load correlated with MI/Cr and Cho/Cr in white matter and NAA/Cr in parietal cortex. HIV infection and aging had additive effects on Cho/Cr and MI/Cr in the basal ganglia and white matter. CONCLUSIONS: The results suggest that glial activation occurs during the NAS stages of HIV infection, whereas further inflammatory activity in the basal ganglia and neuronal injury in the white matter is associated with the development of cognitive impairment. Aging may further exacerbate brain metabolites associated with inflammation in HIV patient and thereby increase the risk for cognitive impairment.


Subject(s)
AIDS Dementia Complex/physiopathology , Aspartic Acid/analogs & derivatives , Brain/physiopathology , Energy Metabolism/physiology , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , AIDS Dementia Complex/diagnosis , AIDS Dementia Complex/drug therapy , Adult , Age Factors , Anti-HIV Agents/therapeutic use , Aspartic Acid/metabolism , Basal Ganglia/drug effects , Basal Ganglia/physiopathology , Brain/drug effects , Brain Mapping , Choline/metabolism , Creatine/metabolism , Energy Metabolism/drug effects , Female , Frontal Lobe/drug effects , Frontal Lobe/physiopathology , HIV Seronegativity/physiology , HIV Seropositivity/physiopathology , Humans , Inositol/metabolism , Male , Memantine/therapeutic use , Middle Aged , Parietal Lobe/drug effects , Parietal Lobe/physiopathology , Reference Values , Treatment Outcome , Viral Load
7.
Am J Pathol ; 159(4): 1541-54, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11583980

ABSTRACT

Neurotrophins and their receptors modulate cerebral cortical development. Tubers in the tuberous sclerosis complex (TSC) are characterized histologically by disorganized cortical cytoarchitecture and thus, we hypothesized that expression of neurotrophin mRNAs and proteins might be altered in tubers. Using in situ transcription and mRNA amplification to probe cDNA arrays, we found that neurotrophin-3 (NT3) and trkB mRNA expression were reduced whereas neurotrophin-4 (NT4) and trkC mRNA expression were increased in whole tuber sections. Alterations in mRNA abundance were defined in single microdissected dysplastic neurons (DNs) and giant cells (GCs). NT3 mRNA expression was reduced in GCs and trkB mRNA expression was reduced in DNs. NT4 mRNA expression was increased in DNs and trkC mRNA expression was increased in both DNs and GCs. In three patients, TSC2 locus mutations were confirmed and the mean tuberin mRNA expression levels was reduced across all nine cases. Consistent with these observations, NT3 mRNA expression was reduced but trkC mRNA expression was increased in vitro in human NTera2 neurons (NT2N) transfected with a tuberin antisense construct that reduced tuberin expression. Western analysis of tuber homogenates and computer-assisted densitometry of immunolabeled sections confirmed the neurotrophin mRNA expression data in whole sections and single neurotrophin immunoreactive cells. We conclude that alterations in NT4/trkB and NT3/trkC expression may contribute to tuber formation during brain development as downstream effects of the hamartin and tuberin pathway in TSC.


Subject(s)
Cerebral Cortex/metabolism , Cerebral Cortex/pathology , Nerve Growth Factors/metabolism , Tuberous Sclerosis/metabolism , Tuberous Sclerosis/pathology , Adolescent , Adult , Antisense Elements (Genetics)/genetics , Blotting, Western , Cell Line , Child , Child, Preschool , Female , Gene Amplification , Gene Expression , Genotype , Giant Cells/physiology , Humans , Immunohistochemistry , Infant , Male , Middle Aged , Nerve Growth Factors/genetics , Neurons/pathology , Neurons/physiology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolism , Transfection , Tuberous Sclerosis/genetics , Tuberous Sclerosis Complex 2 Protein , Tumor Suppressor Proteins
8.
Radiology ; 220(3): 606-10, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11526256

ABSTRACT

PURPOSE: To determine the fractional brain tissue volume changes in the gray matter and white matter of patients with relapsing-remitting multiple sclerosis (MS) and to correlate these measurements with clinical disability and total lesion load. MATERIALS AND METHODS: Thirty patients with relapsing-remitting MS and 25 healthy control subjects underwent magnetic resonance imaging. Fractional brain tissue volumes (tissue volume relative to total intracranial volume) were obtained from the total segmented gray matter and white matter in each group and were analyzed. RESULTS: The fractional volume of white matter versus that of gray matter was significantly lower (-6.4%) in patients with MS (P <.0001) than in control subjects. Neither gray matter nor white matter fractional volume measurements correlated with clinical disability in the patients with MS. CONCLUSION: Loss of brain parenchymal volume in patients with relapsing-remitting MS is predominantly confined to white matter. Analysis of fractional brain tissue volumes provides additional information useful in characterizing MS and may have potential in evaluating treatment strategies.


Subject(s)
Brain/pathology , Magnetic Resonance Imaging , Multiple Sclerosis/pathology , Adult , Atrophy , Female , Humans , Male , Middle Aged , Models, Statistical
9.
Neuropathol Appl Neurobiol ; 27(2): 127-38, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11437993

ABSTRACT

The CXCR3 chemokine receptor, expressed on activated T lymphocytes, is seen within the central nervous system (CNS) in inflammatory conditions where a T-cell response is prominent. However, the distribution of CXCR3 in parenchymal CNS cells is unknown. Using a monoclonal antibody against CXCR3 and post-mortem tissue of patients with and without CNS pathology, we have determined its expression pattern. CXCR3 was found in subpopulations of cells morphologically consistent with astrocytes, particularly reactive astrocytes, and in cerebellar Purkinje cells. It was also detected in arterial endothelial and smooth muscle cells, particularly in areas associated with atherosclerotic plaques. CXCR3-positive astrocytes were particularly prominent in the CNS of HIV-positive patients, in patients with Multiple Sclerosis (MS), in ischaemic infarcts and in astrocytic neoplasms. Immunofluorescence studies of mixed adult primary glial cultures and fetal glial cultures also showed expression of CXCR3 in astrocytes. CXCR3 mRNA was detected in Purkinje cells by in situ hybridization with a CXCR3-specific probe. Thus, the predominant expression of CXCR3 in reactive astrocytes may indicate that it plays a role in the development of reactive gliosis in a variety of infectious, inflammatory, vascular and neoplastic processes in the CNS. The relationship between CXCR3 expression in astrocytes to its expression in Purkinje cells, endothelial cells and smooth muscle cells is yet to be determined.


Subject(s)
Brain Diseases/physiopathology , Receptors, Chemokine/genetics , AIDS Dementia Complex/pathology , AIDS Dementia Complex/physiopathology , Adult , Aged , Astrocytes/cytology , Brain Diseases/pathology , Brain Neoplasms/pathology , Brain Neoplasms/physiopathology , Capillaries/chemistry , Capillaries/physiology , Cells, Cultured , Cerebral Arteries/chemistry , Cerebral Arteries/physiology , Cerebral Veins/chemistry , Cerebral Veins/physiology , Female , Gene Expression , Humans , Male , Middle Aged , Multiple Sclerosis/pathology , Multiple Sclerosis/physiopathology , Purkinje Cells/chemistry , Purkinje Cells/physiology , RNA, Messenger/analysis , Receptors, CXCR3 , Receptors, Chemokine/analysis , Stroke/pathology , Stroke/physiopathology , Temporal Lobe/cytology
10.
AIDS Res Hum Retroviruses ; 17(10): 957-63, 2001 Jul 01.
Article in English | MEDLINE | ID: mdl-11461681

ABSTRACT

There is considerable diversity among HIV-1 strains in terms of their ability to use entry coreceptors on macrophages, especially CXCR4, but it is not known whether virus-specific differences exist among related members of a viral swarm. Defining how entry coreceptors on primary target cells are utilized by the spectrum of HIV-1 variants that emerge in vivo is important for understanding the relationship between coreceptor selectivity and pathogenesis. HIV-1 89.6(PI) is a dual-tropic primary isolate, and the prototype 89.6-cloned R5X4 Env uses both CXCR4 and CCR5 on macrophages. We generated a panel of env clones from the 89.6(PI) quasispecies and found a mixture of R5, R5X4, and X4 variants on the basis of fusion and infection of coreceptor-transfected cell lines. Here we address the use of macrophage coreceptors by these related Envs by analyzing fusion and infection of primary monocyte-derived macrophages mediated specifically through each coreceptor. All R5X4 Envs utilized both CXCR4 and CCR5 on macrophages, while R5 variants used CCR5 only. One variant characterized in cell lines as X4 used both CXCR4 and CCR5 on macrophages. No Env variant fused with macrophages through alternative coreceptor pathways. Thus, there was heterogeneity in coreceptor use among the related Env variants, but use of each coreceptor specifically in macrophages was consistent among members of the viral swarm. Coreceptor use in transfected cells generally predicted use in primary macrophages, although for some Envs macrophages may be a more sensitive indicator of CCR5 use than transfected cell lines.


Subject(s)
Gene Products, env/metabolism , Genetic Variation , HIV-1/genetics , HIV-1/physiology , Macrophages/metabolism , Macrophages/virology , Receptors, CCR5/metabolism , Receptors, CXCR4/metabolism , Cell Line , Gene Products, env/chemistry , Gene Products, env/genetics , HIV-1/isolation & purification , Humans , Membrane Fusion , Receptors, CCR5/genetics , Receptors, CXCR4/genetics
11.
J Peripher Nerv Syst ; 6(1): 2-7, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11293803

ABSTRACT

The role of the human immunodeficiency virus (HIV) and other viruses in the development of neuropathies associated with HIV infection is controversial. Distal symmetric polyneuropathy (DSP), the most common subtype of HIV-associated neuropathy, is characterized by an abundance of reactive macrophages within the peripheral nerve, but HIV replication is limited to a small percentage of the macrophages. Thus, the pathological destruction may be mediated by pro-inflammatory signals amplified by activated glial elements within the nerve, similar to the proposed mechanism of damage caused by HIV within the central nervous system. In contrast, in mononeuropathy multiplex (MM) and progressive polyneuropathy (PP), cytomegalovirus (CMV) replication in the peripheral nerve is consistently demonstrable, and this replication likely results in direct damage to the infected cells (neurons and glia). The rarest form of HIV-associated neuropathy, the diffuse infiltrative lymphocytosis syndrome (DILS), is characterized by an intense CD8+ T lymphocyte infiltration into the nerve and abundant HIV infection of macrophages. Finally, while other viruses (varicella zoster, herpes simplex) are associated with myelitis in HIV-infected individuals, there is little support for a role for these viruses in HIV-associated neuropathy.


Subject(s)
Cytomegalovirus Infections/complications , Cytomegalovirus , HIV Infections/complications , HIV-1 , Polyneuropathies/virology , Humans
12.
AJNR Am J Neuroradiol ; 22(3): 470-5, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11237968

ABSTRACT

BACKGROUND AND PURPOSE: Gray matter may be affected by multiple sclerosis (MS), a white matter disease. Magnetization transfer ratio (MTR) is a sensitive and quantitative marker for structural abnormalities, and has been used frequently in the imaging of MS. In this study, we evaluated the amount of MTR of gray matter among patients with relapsing-remitting MS and healthy control subjects as well as the correlation between gray matter MTR abnormality and neurologic disability associated with relapsing-remitting MS. METHODS: We obtained fast spin-echo dual-echo and magnetization transfer (with and without MT saturation pulses) images from eighteen patients with relapsing-remitting MS and 18 age-matched healthy control subjects. Gray matter was segmented using a semiautomated system. Gray matter MTR histogram parameters, Kurtzke Expanded Disability Status Scale (EDSS), total T2 lesion volume, and gray matter volumes were obtained for statistical analysis. RESULTS: A significant difference was found in gray matter MTR between patients with relapsing-remitting MS and healthy subjects (mean and median). Gray matter MTR histogram normalized peak heights in patients inversely correlated with EDSS (r = -0.65, P =.01). There was also an inverse correlation between mean MTR of gray matter and total T2 lesion volume. CONCLUSION: The MTR of gray matter significantly differed between patients with relapsing-remitting MS and healthy control subjects, suggesting that MS is a more diffuse disease affecting the whole brain, and neuronal damage accumulates in step with T2 lesion volume. Our finding of the relationship between gray matter MTR and EDSS indicates that measurement of gray matter abnormality may be a potentially useful tool for assessing clinical disability in MS.


Subject(s)
Magnetic Resonance Imaging , Multiple Sclerosis, Relapsing-Remitting/diagnosis , Periaqueductal Gray/pathology , Adult , Disability Evaluation , Female , Humans , Male , Middle Aged , Multiple Sclerosis, Relapsing-Remitting/physiopathology , Nervous System/physiopathology , Reference Values
13.
Virology ; 280(2): 243-52, 2001 Feb 15.
Article in English | MEDLINE | ID: mdl-11162838

ABSTRACT

Current retroviral vectors based on murine leukemia virus (MuLV) are unable to efficiently transduce nondividing cells. Lentiviruses, such as the human immunodeficiency virus 1 (HIV-1) are efficient at transducing nondividing, growth-arrested, and post-mitotic cells, but due to complex safety considerations, they may have limited potential for human clinical gene transfer. For this reason, alternatives to MuLV and HIV-1 vectors need to be explored. In this paper, we have found that simian foamy virus vector (SFV-1) containing a CMV-LacZ expression cassette is able to efficiently transduce multiple cell types of various species that include epithelial, lymphoid, and hematopoietic-derived human cell lines and fibroblast cell lines of several species. Previously it was reported that foamy virus replication is cell cycle dependent (P. D. Bieniasz, R. A. Weiss, and M. O. McClure, 1995. J. Virol. 69, 7295-7299). However, others studies demonstrated nuclear import of viral DNA in arrested cells (A. Saibi, F. Puvion-Dutilleul, M. Schmid, J. Peries, and H. d. The 1997. J. Virol. 71, 1155-1161). Here, we show efficient LacZ transduction by SFV-1 vectors in several chemically arrested cell lines and terminally differentiated human neurons. SFV-1 vector can transduce cell lines arrested in G1/S phase of the cell cycle by aphidicolin treatment with similar efficiencies to that of dividing cells. The terminally differentiated human neural cell line, NT2N, was transduced with 30-50% efficiency, corroborating our data obtained with the arrested cell lines. To further examine whether the SFV-1 vector can efficiently deliver a gene into clinically important cells for gene therapy, we transduced primary human peripheral blood cells (PBLs) in the presence and absence of phytohemagglutanin (PHA) stimulation. We observed 81% transduction efficiency in non-stimulated PBLs and 87% in PHA-stimulated PBLs with vector infection carried out twice in 8 hours intervals at a multiplicity of infection of 1. Together, these data indicate that SFV-1 based retroviral vectors may provide a safe, efficient alternative to current onco- and lentiviral vectors for gene transfer in cells from a broad spectrum of lineages across species boundaries.


Subject(s)
Genetic Vectors , Spumavirus/physiology , Animals , COS Cells , Cell Division , Cell Line , Cell Line, Transformed , Chlorocebus aethiops , Genes, Reporter , Genetic Vectors/genetics , HeLa Cells , Humans , K562 Cells , Lac Operon , Leukocytes, Mononuclear/cytology , Mice , Spumavirus/genetics , Tumor Cells, Cultured
14.
Radiology ; 216(2): 351-5, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10924552

ABSTRACT

PURPOSE: To investigate and characterize the global distribution of magnetization transfer (MT) ratio values of normal-appearing white matter (NAWM) in patients with relapsing-remitting multiple sclerosis (MS) and test the hypothesis that the MT histogram for NAWM reflects disease progression. MATERIALS AND METHODS: Conventional and MT magnetic resonance (MR) images were obtained in 23 patients and 25 healthy volunteers. Clinical tests for comparison with the MT histogram parameters included the Extended Disability Status Scale and the ambulation index. Lesion load calculated with T2-weighted MR images and whole-brain and white matter volumes were measured. RESULTS: The location of the MT histogram peak and the mean MT ratio for NAWM were significantly lower in patients with MS than in control subjects. In longitudinal studies, the histogram peak location and mean MT ratio shifted in the direction of normal values as the duration of disease increased. A mean of 26.5% of the volume of new lesions identified on the later studies were demonstrated to have originated in NAWM corresponding to "lost" pixels on the histogram. CONCLUSION: MT histogram analysis of NAWM, including longitudinal analysis, may provide new prognostic information regarding lesion formation and increase understanding of the course of the disease.


Subject(s)
Brain/pathology , Magnetic Resonance Imaging/methods , Multiple Sclerosis, Relapsing-Remitting/pathology , Adult , Disabled Persons/classification , Disease Progression , Female , Follow-Up Studies , Humans , Image Processing, Computer-Assisted/methods , Longitudinal Studies , Male , Multiple Sclerosis, Relapsing-Remitting/diagnosis , Multiple Sclerosis, Relapsing-Remitting/physiopathology , Neurologic Examination , Prognosis , Reference Values , Walking/physiology
16.
Neuroscience ; 97(3): 591-600, 2000.
Article in English | MEDLINE | ID: mdl-10828541

ABSTRACT

Functional chemokine receptors and chemokines are expressed by glial cells within the CNS, though relatively little is known about the patterns of neuronal chemokine receptor expression and function. We developed monoclonal antibodies to the CCR1, CCR2, CCR3, CCR6, CXCR2, CXCR3 and CXCR4 chemokine receptors to study their expression in human fetal neurons cultured from brain tissue as well as the clonally derived NT2.N human neuronal cell line (NTera 2/cl.D1). Specific monoclonal antibody labeling demonstrated expression of CCR2, CXCR2, CXCR3 and CXCR4 on neurons from both sources. Co-labeling studies revealed strong expression of CXCR3 and CXCR4 on both dendritic and axonal processes, with a weaker expression of CXCR2 and CCR2. Reverse transcriptase-polymerase chain reaction analysis of pure NT2.N neurons confirmed RNA expression for CCR2, CXCR2, CXCR3 and CXCR4. No changes in the neuronal labeling pattern of chemokine receptor expression were noted when NT2.N neurons were grown on a supporting layer of astrocytes, again consistent with similar patterns seen in primary human fetal brain cultures. Analysis of single-cell calcium transients revealed a robust response to stromal derived factor-1alpha (CXCR4) and melanocyte growth-stimulating activity (CXCR2), and variable response to monocyte chemoattractant protein-1 (CCR2) or interferon-gamma inducible protein-10 (CXCR3). Finally, we detected the release of monocyte chemoattractant protein-1 from pure cultures of NT2.N neurons, but not undifferentiated NT2 cells. These data indicate that individual neurons may not only co-express multiple functional chemokine receptors, but also that neurons themselves produce chemokines which may influence cellular function within the central nervous system.


Subject(s)
Chemokine CCL2/metabolism , Neurons/metabolism , Receptors, Chemokine/metabolism , Astrocytes/cytology , Astrocytes/immunology , Astrocytes/metabolism , Brain/embryology , Brain/immunology , Brain/metabolism , Calcium Signaling/physiology , Cell Communication/physiology , Fetus , Humans , Neurons/cytology , Neurons/immunology , RNA, Messenger/metabolism , Receptors, Chemokine/genetics , Signal Transduction/physiology , Teratocarcinoma , Tumor Cells, Cultured
17.
J Neurovirol ; 6 Suppl 1: S61-9, 2000 May.
Article in English | MEDLINE | ID: mdl-10871767

ABSTRACT

APJ is a recently described seven-transmembrane (7TM) receptor that is abundantly expressed in the central nervous system (CNS). This suggests an important role for APJ in neural development and/or function, but neither its cellular distribution nor its function have been defined. APJ can also serve as a co-receptor with CD4 for fusion and infection by some strains of human immunodeficiency virus (HIV-1) in vitro, suggesting a role in HIV neuropathogenesis if it were expressed on CD4-positive CNS cells. To address this, we examined APJ expression in cultured neurons, astrocytes, oligodendrocytes, microglia and monocyte-derived macrophages utilizing both immunocytochemical staining with a polyclonal anti-APJ antibody and RT - PCR. We also analyzed the ability of a recently identified APJ peptide ligand, apelin, to induce calcium elevations in cultured neural cells. APJ was expressed at a high level in neurons and oligodendrocytes, and at lower levels in astrocytes. In contrast, APJ was not expressed in either primary microglia or monocyte-derived macrophages. Several forms of the APJ peptide ligand induced calcium elevations in neurons. Thus, APJ is selectively expressed in certain CNS cell types and mediates intracellular signals in neurons, suggesting that APJ may normally play a role in signaling in the CNS. However, the absence of APJ expression in microglia and macrophages, the prinicpal CD4-positive cell types in the brain, indicates that APJ is unlikely to mediate HIV-1 infection in the CNS.


Subject(s)
Astrocytes/metabolism , Macrophages/metabolism , Microglia/metabolism , Neurons/metabolism , Oligodendroglia/metabolism , Receptors, Dopamine D2/metabolism , Receptors, G-Protein-Coupled , Adult , Amino Acid Sequence , Antibodies , Apelin Receptors , Blotting, Southern , Brain/cytology , Brain/metabolism , Calcium/metabolism , Fetus , Fluorescent Antibody Technique, Indirect , Humans , Molecular Sequence Data , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction
18.
Mult Scler ; 6(1): 3-13, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10694839

ABSTRACT

In recent years we have seen growing evidence for the role of chemokines in the pathogenesis of several infectious and non-infectious inflammatory CNS disease states, including Multiple Sclerosis (MS) and its animal model, experimental allergic encephalomyelitis (EAE). An increase in proinflammatory chemokines has been associated with demyelinating lesions and clinical neurological dysfunction in patients with MS; these chemokines could be potential targets for MS therapy. Besides a clearly defined role in mediating leukocyte migration, these and other chemokines may act as immunoregulatory molecules in the driving to Th1/Th2 responses, switch of cytokine profiles, and the induction of tolerance. Since chemokine receptors have now been identified on macrophages, microglia, astrocytes, and endothelial cells as well as neurons in the CNS, chemokine/receptor interactions may mediate functional responses in a variety of CNS cell types during the course of inflammatory disease states. Therefore, clarification of the roles of chemokines and their receptors in the pathogenesis of EAE and MS will be useful in establishing immunotherapeutic strategies for these neurological autoimmune disorders.


Subject(s)
Chemokines/immunology , Multiple Sclerosis/etiology , Multiple Sclerosis/immunology , Receptors, Chemokine/immunology , Humans
19.
Radiology ; 214(3): 665-70, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10715027

ABSTRACT

PURPOSE: To determine annual rates of volumetric changes in the whole-brain parenchyma of patients with relapsing-remitting and secondary progressive multiple sclerosis (MS) and test the hypothesis that these changes correlate with clinical disability. MATERIALS AND METHODS: A computer-assisted segmentation technique with thin-section magnetic resonance (MR) imaging was used in 36 patients with MS (27 relapsing-remitting, nine secondary progressive) and in 20 control subjects to quantify brain and cerebrospinal fluid volumes. To determine the degree of brain atrophy, the percentage brain parenchyma volume (PBV) relative to that of intracranial contents was calculated. RESULTS: At the beginning of the study, the PBV was smaller in the MS group than in the control group (P = .007); brain parenchyma volumes were similar. The median rate of brain volume loss was 17.3 mL per year in patients with relapsing-remitting MS and 23.6 mL per year in those with secondary progressive MS. There was a negative correlation between brain atrophy and Expanded Disability Status Scale (EDSS) score in patients with secondary progressive MS (r = -0.69, P = .004) and no correlation in patients with relapsing-remitting MS. T2 lesion volume did not correlate with brain atrophy in either group. CONCLUSION: The correlation between brain atrophy and EDSS score was better in patients with secondary progressive MS than in those with relapsing-remitting MS.


Subject(s)
Brain/pathology , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Multiple Sclerosis, Chronic Progressive/diagnosis , Multiple Sclerosis, Relapsing-Remitting/diagnosis , Adult , Atrophy , Cerebrospinal Fluid , Disability Evaluation , Female , Humans , Male , Middle Aged
20.
Neurology ; 54(4): 813-7, 2000 Feb 22.
Article in English | MEDLINE | ID: mdl-10690968

ABSTRACT

OBJECTIVE: To evaluate the efficacy of glatiramer acetate (GA, Copaxone; Teva Pharmaceutical Industries, Ltd., Petah Tiqva, Israel) by MRI-based measures in patients with relapsing-remitting (RR) MS. METHODS: Twenty-seven patients with clinically definite RR-MS were treated with either 20 mg of GA by daily subcutaneous self-injection (n = 14) or placebo (n = 13) for approximately 24 months. Axial dual-echo fast-spin-echo T2-weighted images and T1-weighted images before and after gadolinium (Gd) were acquired at 1.5 tesla and transferred into an image processing computer system. The main outcome measures were the number of Gd-enhanced T1 and T2 lesions and their volume as well as brain parenchyma volume. RESULTS: The values of age, disease duration, Expanded Disability Status Scale (EDSS) score, the number of T1- and T2-weighted lesions, and their volume were similar between GA- and placebo-receiving groups at the entry of this study. There was a decrease in the number of T1-enhanced lesions (p = 0.03) and a significant percent annual decrease of their volume in GA recipients compared with those of placebo recipients. There were no significant differences between changes in the two groups in the number of T2 lesions and their volume. The loss of brain tissue was significantly smaller in the GA group compared with that of the placebo group. CONCLUSIONS: These results show that GA treatment may decrease both lesion inflammation and the rate of brain atrophy in RR-MS.


Subject(s)
Brain/pathology , Immunosuppressive Agents/therapeutic use , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Multiple Sclerosis, Relapsing-Remitting/pathology , Peptides/therapeutic use , Adult , Atrophy , Glatiramer Acetate , Humans , Magnetic Resonance Imaging , Middle Aged
SELECTION OF CITATIONS
SEARCH DETAIL
...