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Kinman LM, Worlein JM, Leigh J, Bielefeldt-Ohmann H, Anderson DM, Hu SL, Morton WR, Anderson BD, Ho RJY. HIV in central nervous system and behavioral development: an HIV-2287 macaque model of AIDS. AIDS 2004; 18:1363-70. [PMID: 15199312 DOI: 10.1097/01.aids.0000131307.62828.a1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine which route of inoculation produced consistent and frequent HIV infection in the central nervous system (CNS) and alterations in cognitive and motor development in infant macaques. METHODS Infant macaques (Macaca nemestrina) were inoculated with the highly pathogenic strain HIV-2287 intravenously (n = 3) or intrathecally (n = 3). Uninfected infants were evaluated as controls. Disease progression was evaluated by virological assessment of blood and cerebral spinal fluid (CSF), CD4 T cell count in blood, and quinolinic acid levels in CSF (a surrogate marker of neuronal cell damage). The effect of HIV infection on cognitive and motor development in infants was monitored during the 6-month study. RESULTS Either route of HIV-2287 inoculation produced detectable viral RNA in CSF and productive infection in blood. Detection of virus in CSF paralleled a rise in quinolinic acid levels. All HIV-infected infants experienced a severe and rapid decline in CD4 T cell counts by 10 weeks after viral infection. HIV-infected infants, particularly those infected by the intravenous route, exhibited delays in reaching cognitive and motor milestones, which paralleled neuropathological changes. CONCLUSIONS The HIV-2287 infant model produced a high incidence of viral infection in the CNS regardless of the route of inoculation. Significant alteration in neurobehavioral development was observed in HIV-infected infants, and this measure was significantly impaired particularly in infants infected by the intravenous route. These data, coupled with the ability to detect viral RNA and changes in quinolinic acid levels in CSF, may allow quantitative evaluation of drug and immune candidates for treating neurological effects of AIDS.
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Affiliation(s)
- Loren M Kinman
- Department of Pharmaceutics and Washington National Primate Research Center, University of Washington, Seattle Washington 98195-7610, USA
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202
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Shin WH, Lee DY, Park KW, Kim SU, Yang MS, Joe EH, Jin BK. Microglia expressing interleukin-13 undergo cell death and contribute to neuronal survival in vivo. Glia 2004; 46:142-52. [PMID: 15042582 DOI: 10.1002/glia.10357] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
How to minimize brain inflammation is pathophysiologically important, since inflammation induced by microglial activation can exacerbate brain damage. In the present report, we show that injection of lipopolysaccharide (LPS) into the rat cortex led to increased levels of interleukin-13 (IL-13) and to IL-13 immunoreactivity, followed by the substantial loss of microglia at 3 days post-LPS. IL-13 levels in LPS-injected cortex reached a peak at 12 h post-injection, remained elevated at 24 h, and returned to basal levels at day 4. In parallel, IL-13 immunoreactivity was detected as early as 12 h post-LPS and maintained up to 24 h; it disappeared at 4 days. Surprisingly, IL-13 immunoreactivity was detected exclusively in microglia, but not in neurons or astrocytes. Following treatment with LPS in vitro, IL-13 expression was also induced in microglia in the presence of neurons, but not in the presence of astrocytes or in cultured pure microglia alone. In experiments designed to determine the involvement of IL-13 in microglia cell death, IL-13-neutralizing antibodies significantly increased survival of activated microglia at 3 days post-LPS. Consistent with these results, the expression of inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-alpha) was sustained in activated microglia and neuronal cell death was consequently increased. Taken together, the present study is the first to demonstrate the endogenous expression of IL-13 in LPS-activated microglia in vivo, and to demonstrate that neurons may be required for IL-13 expression in microglia. Our data strongly suggest that IL-13 may control brain inflammation by inducing the death of activated microglia in vivo, resulting in an enhancement of neuronal survival.
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Affiliation(s)
- Won Ho Shin
- Brain Disease Research Center, Ajou University School of Medicine, Suwon, Korea
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203
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Venneti S, Lopresti BJ, Wang G, Bissel SJ, Mathis CA, Meltzer CC, Boada F, Capuano S, Kress GJ, Davis DK, Ruszkiewicz J, Reynolds IJ, Murphey-Corb M, Trichel AM, Wisniewski SR, Wiley CA. PET imaging of brain macrophages using the peripheral benzodiazepine receptor in a macaque model of neuroAIDS. J Clin Invest 2004; 113:981-9. [PMID: 15057304 PMCID: PMC379322 DOI: 10.1172/jci20227] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2003] [Accepted: 01/20/2004] [Indexed: 11/17/2022] Open
Abstract
HIV infection in humans and simian immunodeficiency virus (SIV) infection in macaques result in encephalitis in approximately one-quarter of infected individuals and is characterized by infiltration of the brain with infected and activated macrophages. 1-(2-chlorphenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinoline-carboxamide (PK11195) is a ligand specific for the peripheral benzodiazepine receptor abundant on macrophages and is expressed in low levels in the noninfected brain. We hypothesized that positron-emission tomography (PET) with the carbon-11-labeled, R-enantiomer form of PK11195 ([(11)C](R)-PK11195) could image brain macrophages and hence the development of encephalitis in vivo. [(11)C](R)-PK11195 binding was assessed in the brain using PET in 11 SIV infected macaques, six of which showed increased binding in vivo. Postmortem examination of the brain in these six macaques demonstrated encephalitis, while macaques that did not show an increase in [(11)C](R)-PK11195 binding did not develop SIV encephalitis. Brain tissue from SIV encephalitic macaques also showed increased [(3)H](R)-PK11195 binding compared with binding in nonencephalitic macaques. Increased PK11195 binding in vivo and in postmortem brain tissue correlated with abundance of macrophages but not astrocytes. Our results suggest that PET [(11)C](R)-PK11195 imaging can detect the presence of macrophages in SIV encephalitis in vivo and may be useful to predict the development of HIV encephalitis and in studies of the pathogenesis and treatment of HIV dementia.
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Affiliation(s)
- Sriram Venneti
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pennsylvania, USA
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204
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Venneti S, Lopresti BJ, Wang G, Bissel SJ, Mathis CA, Meltzer CC, Boada F, Capuano S, Kress GJ, Davis DK, Ruszkiewicz J, Reynolds IJ, Murphey-Corb M, Trichel AM, Wisniewski SR, Wiley CA. PET imaging of brain macrophages using the peripheral benzodiazepine receptor in a macaque model of neuroAIDS. J Clin Invest 2004. [DOI: 10.1172/jci200420227] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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205
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Wei R, Xia ZL, Chen B, Han JJ, Ren DL, Yang MF. CD14 + cell dysfunction in patients with chronic active hepatitis B. Shijie Huaren Xiaohua Zazhi 2004; 12:618-621. [DOI: 10.11569/wcjd.v12.i3.618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the functional states of CD14+ cells in peripheral blood mononuclear cell (PBMCs) by analyzing the expression of early active antigen, production of pro-inflammatory cytokines and phagocytosis with flow cytometry (FCM).
METHODS: PBMCs were isolated from 11 patients with chronic active hepatitis B and 10 healthy blood donors, and 4-color flow cytometry and gate setting techniques were applied. The percentage of CD14+ cells and level of CD14 antigen were tested by FCM, after gate setting with CD14, side scatter (SSC) and activation-linked surface antigen (CD69) expression rate, percentage of TNF-α producing cells, level of intro-cellular TNF-α, the percentage of phagocytes and the ability of phagocytosis were investigated.
RESULTS: The SSC mean value of CD14+ cell of HBV patients was higher than that of health control (P < 0.01); There were no difference between two testing groups on the percentage of CD14+ cells and level of CD14 antigen, however the level of CD14 antigen was positively associated with the percentage of CD14+ cells. CD14/69 double expression rate was significantly higher than that of control group (P < 0.01); No difference was observed on CD14/TNF-α double stain cells between testing groups; In comparison with control group, the level of cellular TNF-α in HBV group was higher (P < 0.05). In control group, the percentage of TNF-α producing cells were correlated with SSC value and number of phagocytes that expressed CD14/69. There was no difference in phagocytes that expressed CD14/69 in two groups. As compared with the control group, there was more phagocytostic CD14+ cells in HBV group (P < 0.01), but the mean phagocytosis amount was significantly lower in this group (P < 0.05), and the number of phagocyte was negatively correlated with the level of CD14 antigen; while the SSC value and number of TNF-αproducing cells were negatively correlated with level of CD14 antigen.
CONCLUSION: CD14+ cells in PBMCs from chronic active hepatitis B patients are over activated in a dysfunction stage.
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206
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Haas DW, Johnson BW, Spearman P, Raffanti S, Nicotera J, Schmidt D, Hulgan T, Shepard R, Fiscus SA. Two phases of HIV RNA decay in CSF during initial days of multidrug therapy. Neurology 2004; 61:1391-6. [PMID: 14638961 DOI: 10.1212/wnl.61.10.1391] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Defining cellular and tissue sources of HIV-1 in CSF is important for understanding disease pathogenesis and optimal therapies for HIV infection in the brain. OBJECTIVE To identify the time of maximal viral decay in CSF during the initial days of antiretroviral therapy. METHODS Serial CSF and plasma data were available from four adults who underwent ultraintensive CSF sampling for 48 hours at baseline and again beginning 72 hours after starting antiretroviral therapy. Regression lines were generated using HIV-1 RNA data from 17 on-treatment serial CSF samples obtained at 3-hour intervals. Viral RNA was quantified by Nuclisens and Amplicor HIV-1 Monitor assays. RESULTS Extrapolation of regression lines intersected baseline below actual baseline CSF HIV-1 RNA concentrations, indicating that virus decayed most rapidly on days 1 through 3 with half-lives of no more than 0.9 to 2.8 days. Half-lives on days 4 and 5 ranged from 1.3 to 4.9 days. Plasma data also showed early rapid decay. CONCLUSIONS Multiple phases of viral decay suggest that virus in CSF originates from at least two sources during untreated, asymptomatic HIV-1 infection. The short half-life indicates that the primary source is CD4+ T cells. Sampling during days 1 through 3 and different stages of disease will better define sources of virus.
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Affiliation(s)
- D W Haas
- Department of Medicine, Division of Infectious Diseases, Vanderbilt University School of Medicine, Nashville, TN 37203, USA.
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207
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Gekker G, Hu S, Wentland MP, Bidlack JM, Lokensgard JR, Peterson PK. κ-Opioid Receptor Ligands Inhibit Cocaine-Induced HIV-1 Expression in Microglial Cells. J Pharmacol Exp Ther 2004; 309:600-6. [PMID: 14757849 DOI: 10.1124/jpet.103.060160] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cocaine abuse has been implicated as a cofactor in human immunodeficiency virus (HIV)-1-associated dementia (HAD). In this study, we tested the hypothesis that exposure of microglial cells, the resident macrophages of the brain, to cocaine would potentiate HIV-1 expression. Because kappa-opioid receptor (KOR) agonists have been shown to suppress neurochemical and neurobehavioral responses to cocaine and to inhibit HIV-1 expression in microglial cell cultures, we also postulated that KOR ligands would inhibit cocaine-induced potentiation of HIV-1 expression. Human microglial cells were infected with HIV-1(SF162), an R5 isolate, and viral expression was quantified by measurement of p24 antigen in culture supernatants. Treatment of microglia with the KOR agonists trans-(+/-)-3,4-dichlor-N-methyl-N-(2[1-pyrrolidnyl])benzeneacetamide methanesulfonate and 8-carboxamidocyclazocine inhibited viral expression (maximal suppression of 42 and 48%, respectively). Consistent with the hypotheses, treatment of microglia with cocaine promoted HIV-1 expression (maximal enhancement of 54%), and pretreatment of microglia with these KOR agonists as well as with the KOR-selective antagonist nor-binaltorphimine abrogated cocaine-induced potentiation of viral expression. Results of flow cytometry studies suggested that the mechanism whereby KOR ligands inhibit cocaine's stimulatory effect on viral expression involves the suppression of cocaine-induced activation of extracellular signal-regulated kinase1/2, thereby blunting cocaine-enhanced up-regulation of the HIV-1 entry chemokine coreceptor CCR5. The findings of this study suggest that in addition to its neurotoxic effects, cocaine could foster development of HAD by potentiating viral expression in the brain and that this phenomenon is inhibited by KOR ligands.
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Affiliation(s)
- Genya Gekker
- Neuroimmunology Research Laboratory, Minneapolis Medical Research Foundation and Department of Medicine, University of Minnesota Medical School, USA
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208
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Barber SA, Uhrlaub JL, DeWitt JB, Tarwater PM, Zink MC. Dysregulation of mitogen-activated protein kinase signaling pathways in simian immunodeficiency virus encephalitis. THE AMERICAN JOURNAL OF PATHOLOGY 2004; 164:355-62. [PMID: 14742241 PMCID: PMC1602250 DOI: 10.1016/s0002-9440(10)63125-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/10/2003] [Indexed: 10/18/2022]
Abstract
Central nervous system (CNS) disease is a frequent complication of human immunodeficiency virus (HIV)-1 infection. Identification of cellular mechanisms that control virus replication and that mediate development of HIV-associated neuropathology will provide novel strategies for therapeutic intervention. The milieu of the CNS during HIV infection is extraordinarily complex because of infiltration of inflammatory cells and production of chemokines, cytokines, and neurotoxic molecules. Cells in the CNS must integrate signaling pathways activated simultaneously by products of virus replication and infiltrating immune cells. In this study, we examined activation of mitogen-activated protein kinases (MAPKs) in the CNS of simian immunodeficiency virus-infected macaques during acute, asymptomatic, and terminal infection. We demonstrate that significantly increased (P < 0.02) activation of ERK MAPK, typically associated with anti-apoptotic and neuroprotective pathways, occurs predominantly in astrocytes and immediately precedes suppression of virus replication and macrophage activation that occur after acute infection. In contrast, significantly increased activation of proapoptotic, neurodegenerative MAPKs JNK (P = 0.03; predominantly in macrophages/microglia), and p38 (P = 0.03; predominantly in neurons and astrocytes) after acute infection correlates with subsequent resurgent virus replication and development of neurological lesions. This shift from classically neuroprotective to neurodegenerative MAPK pathways suggests that agents that inhibit activation of JNK/p38 may be protective against HIV-associated CNS disease.
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Affiliation(s)
- Sheila A Barber
- Department of Comparative Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.
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209
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Sánchez-Alavez M, Gombart LM, Huitrón-Reséndiz S, Carr JR, Wills DN, Berg G, Campbell IL, Gauvin DV, Henriksen SJ, Criado JR. Physiological and behavioral effects of methamphetamine in a mouse model of endotoxemia: a preliminary study. Pharmacol Biochem Behav 2004; 77:365-70. [PMID: 14751466 DOI: 10.1016/j.pbb.2003.11.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We investigated the effects of methamphetamine (METH) on core body temperature (Tb) and motor activity (MA) with or without exposure to a peripheral immune challenge. Mice were exposed to an escalating METH treatment and then to a METH treatment known to cause neurotoxicity (binge METH treatment). This was followed by a challenge with lipopolysaccharide (LPS). Three days later, METH and saline-treated control groups were challenged with an acute test dose of METH (METH test). Animals exposed to the escalating METH treatment exhibited a significant increase in Tb only after the initial exposure to METH (Day 1) and following the METH test (Day 7). The hyperthermic effect produced by the METH test (Day 7) was reduced in mice previously exposed to combined exposure to binge METH and LPS treatments. The escalating METH treatment produced MA sensitization to the METH test. Animals treated with the binge METH, LPS injection or both treatments combined prevented MA sensitization to the METH test. These findings suggest that induction of peripheral endotoxemia in animals with a history of METH reduced the hyperthermic response to a subsequent challenge with METH.
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Affiliation(s)
- Manuel Sánchez-Alavez
- Department of Neuropharmacology, The Scripps Research Institute, CVN-13, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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210
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Valcour VG, Shikuma CM, Watters MR, Sacktor NC. Cognitive impairment in older HIV-1-seropositive individuals: prevalence and potential mechanisms. AIDS 2004; 18 Suppl 1:S79-86. [PMID: 15075502 PMCID: PMC1388077 DOI: 10.1097/00002030-200401001-00012] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Individuals over 50 years of age comprise 11% of AIDS cases reported to the Centers for Disease Control and Prevention. A higher prevalence of AIDS in older individuals has been reported in certain states including Hawaii (20%) and Florida (13%). Although life expectancy in individuals with AIDS has increased with advances in antiretroviral therapy, it is likely that there are health consequences both of long-term infection and chronic antiretroviral therapy. Given the general increase in neurological disorders with age and the relatively high prevalence of cognitive dysfunction associated with HIV itself, the risk of HIV-associated dementia (HAD) in this aging HIV-seropositive subgroup is of particular concern. Existing data suggest, but have not conclusively demonstrated, increased rates of HAD in older compared with younger seropositive individuals. Preliminary data from the Hawaii Aging with HIV Cohort, a prospective cohort study designed to address this issue definitively, are presented. Factors underlying this hypothesized susceptibility in older individuals are discussed, including a synergy among HAD and other dementias, the role of vascular co-pathology, HIV and age-related immunological changes, and detrimental neuroglial changes that limit the compensatory ability of the aging brain.
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Affiliation(s)
- Victor G Valcour
- University of Hawaii, NeuroAIDS Specialized Neuroscience Research Program, John A. Burns School of Medicine, Honolulu, Hawaii 96816, USA.
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211
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212
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Caught in the act: in vivo mapping of macrophage infiltration in nerve injury by magnetic resonance imaging. J Neurosci 2003. [PMID: 14645484 DOI: 10.1523/jneurosci.23-34-10892.2003] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In vivo tracking of hematogenous macrophages has been a major challenge because these cells are key players in nerve injury and repair. We visualized the spatiotemporal course of macrophage infiltration after acute peripheral nerve injury in living rats by using superparamagnetic iron oxide (SPIO) particles and magnetic resonance imaging (MRI). A signal loss on MR images indicating iron accumulation was present in degenerating sciatic nerves between days 1 and 8 after a crush lesion, ceased thereafter, and corresponded to the transient presence of iron-labeled ED1-positive macrophages in tissue sections. In contrast, no SPIO accumulation was seen after optic nerve crush, which revealed microglial activation but lacked macrophage infiltration. SPIO-enhanced MRI provides a new tool to selectively visualize active periods of macrophage transmigration into the nervous system, thus enabling dynamic views on a fundamental process in a multitude of nerve disorders.
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213
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Kim WK, Corey S, Alvarez X, Williams K. Monocyte/macrophage traffic in HIV and SIV encephalitis. J Leukoc Biol 2003; 74:650-6. [PMID: 12960230 DOI: 10.1189/jlb.0503207] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
This short review focuses on the role of central nervous system (CNS) perivascular macrophages as targets of productive infection of the CNS. Data discussed include the importance of these cells as early targets of infection and their productive infection with AIDS. Many of the immune molecules on perivascular macrophages are also found on subsets of blood monocyte/macrophages, some of which are expanded during human immunodeficiency virus (HIV) infection. These observations paired with the known bone marrow (BM) origin of perivascular macrophages and the BM as a site of HIV infection underscore the importance of the study of monocyte populations in the BM and blood, which are activated and infected as a source of virus that enters the CNS. Data presented and discussed herein suggest a role of HIV-infected BM-derived monocytes as "Trojan horse" cells that traffic to the CNS to become perivascular macrophages. The study of such cells including their timing of infection, activation, and traffic and the role of HIV-specific immune responses controlling their accumulation in the CNS warrant study with regard to CNS neuropathogenesis.
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Affiliation(s)
- Woong-Ki Kim
- Division of Pathogenesis, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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214
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Lee C, Liu QH, Tomkowicz B, Yi Y, Freedman BD, Collman RG. Macrophage activation through CCR5- and CXCR4-mediated gp120-elicited signaling pathways. J Leukoc Biol 2003; 74:676-82. [PMID: 12960231 DOI: 10.1189/jlb.0503206] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Macrophages are major targets for infection by human immunodeficiency virus type 1 (HIV-1). In addition to their role as productive viral reservoirs, inappropriate activation of infected and uninfected macrophages appears to contribute to pathogenesis. HIV-1 infection requires initial interactions between the viral envelope surface glycoprotein gp120, the cell-surface protein CD4, and a chemokine receptor CCR5 or CXCR4. Besides their role in HIV-1 entry, CCR5 and CXCR4 are G protein-coupled receptors that can activate multiple intracellular signaling pathways. HIV-1 gp120 has been shown to activate signaling pathways through the chemokine receptors in several cell types including lymphocytes, neurons, and astrocytes. In some cell types, these consequences may cause cellular injury. In this review, we highlight our data demonstrating diverse signaling events that occur in primary human macrophages in response to gp120/chemokine receptor interactions. These responses include K+, Cl-, and nonselective cation currents, intracellular Ca2+ increases, and activation of several kinases including the focal adhesion-related tyrosine kinase Pyk2, mitogen-activated protein kinases (MAPK), and phosphoinositol-3 kinase. Activation of the MAPK leads to gp120-induced expression of chemokines such as monocyte chemoattractant protein-1 and macrophage-inflammatory protein-1beta and the proinflammatory cytokine tumor necrosis factor alpha. These responses establish a complex cytokine network, which may enhance or suppress HIV-1 replication. In addition, dysregulation of macrophage function by gp120/chemokine receptor signaling may contribute to local inflammation and injury and further recruit additional inflammatory and/or target cells. Targeting these cellular signaling pathways may have benefit in controlling inflammatory sequelae of HIV infection such as in neurological disease.
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Affiliation(s)
- ChuHee Lee
- Department of Medicine, School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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215
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Wang EJ, Sun J, Pettoello-Mantovani M, Anderson CM, Osiecki K, Zhao ML, Lopez L, Lee SC, Berman JW, Goldstein H. Microglia from mice transgenic for a provirus encoding a monocyte-tropic HIV type 1 isolate produce infectious virus and display in vitro and in vivo upregulation of lipopolysaccharide-induced chemokine gene expression. AIDS Res Hum Retroviruses 2003; 19:755-65. [PMID: 14585206 DOI: 10.1089/088922203769232557] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A large body of evidence has indicated that microglia are the predominant cellular location for HIV-1 in the brains of HIV-1-infected individuals and play a direct role in the development of HIV-1-associated dementia (HAD). Therefore, investigation of the mechanism by which HIV-1-infected microglia contribute to the development of HIV-associated dementia should be facilitated by the creation of a mouse model wherein microglia carry replication-competent HIV-1. To circumvent the inability of HIV-1 to infect mouse cells, we developed a mouse line that is transgenic for a full-length proviral clone of a monocyte-tropic HIV-1 isolate, HIV-1(JR-CSF) (JR-CSF mice), whose T cells and monocytes produce infectious HIV-1. We detected expression of the long terminal repeat-regulated proviral transgene in the microglia of these transgenic mice and demonstrated that it was increased by in vitro and in vivo stimulation with lipopolysaccharide. Furthermore, microglia isolated from JR-CSF mouse brains produced HIV-1 that was infectious in vitro and in vivo. We examined the effect that carriage of the HIV-1 provirus had on chemokine gene regulation in the brains of these mice and demonstrated that MCP-1 gene expression by JR-CSF mouse microglia and brains was more responsive to in vitro and in vivo stimulation with lipopolysaccharide than were microglia and brains from control mice. Thus, this study indicates that the JR-CSF mice may represent a new mouse model to study the effect of HIV-1 replication on microglia function and its contribution to HIV-1-associated neurological disease.
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Affiliation(s)
- Emilie-Jeanne Wang
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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216
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Roffê E, Silva AA, Marino APMP, dos Santos PVA, Lannes-Vieira J. Essential role of VLA-4/VCAM-1 pathway in the establishment of CD8+ T-cell-mediated Trypanosoma cruzi-elicited meningoencephalitis. J Neuroimmunol 2003; 142:17-30. [PMID: 14512161 DOI: 10.1016/s0165-5728(03)00254-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Central nervous system (CNS) damage can occur during Trypanosoma cruzi infection, especially in immunosuppressed patients. The enhanced susceptibility of C3H/He mice to CD8-mediated acute meningoencephalitis is associated with higher up-regulation of vascular cell adhesion molecule-1 (VCAM-1) on CNS vascular endothelia than in the less susceptible C57BL/6. Further, in vitro adhesion of activated peripheral blood cells to CNS blood vessels was abrogated by anti-VLA-4 antibodies that also inhibited cell migration into the CNS of T. cruzi-infected mice. Lastly, the reactivation of meningoencephalitis in immunosuppressed chronically infected mice was associated with VCAM-1 up-regulation. Therefore, we hypothesize that VLA-4/VCAM-1 pathway plays a pivotal role in the establishment of T. cruzi-elicited encephalitis.
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MESH Headings
- Animals
- Antigens, Protozoan/analysis
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/parasitology
- Cell Adhesion/immunology
- Cell Movement/immunology
- Central Nervous System Protozoal Infections/immunology
- Central Nervous System Protozoal Infections/metabolism
- Central Nervous System Protozoal Infections/parasitology
- Central Nervous System Protozoal Infections/pathology
- Chagas Disease/immunology
- Chagas Disease/metabolism
- Chagas Disease/parasitology
- Chagas Disease/pathology
- Chronic Disease
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/immunology
- Endothelium, Vascular/parasitology
- Endothelium, Vascular/pathology
- Female
- Genetic Predisposition to Disease
- Immunophenotyping
- Immunosuppressive Agents/administration & dosage
- Integrin alpha4beta1/biosynthesis
- Integrin alpha4beta1/physiology
- Intercellular Adhesion Molecule-1/biosynthesis
- Leukocytes, Mononuclear/chemistry
- Leukocytes, Mononuclear/immunology
- Leukocytes, Mononuclear/parasitology
- Meningoencephalitis/immunology
- Meningoencephalitis/metabolism
- Meningoencephalitis/parasitology
- Meningoencephalitis/pathology
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Recurrence
- Signal Transduction/immunology
- Trypanosoma cruzi/immunology
- Vascular Cell Adhesion Molecule-1/biosynthesis
- Vascular Cell Adhesion Molecule-1/physiology
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Affiliation(s)
- Ester Roffê
- Laboratório de Autoimunidade e Imuno-regulação, Departamento de Imunologia, Instituto Oswaldo Cruz-Fundação Oswaldo Cruz, Av. Brasil, 4365 Rio de Janeiro, RJ 21045-900, Brazil
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Zelivyanskaya ML, Nelson JA, Poluektova L, Uberti M, Mellon M, Gendelman HE, Boska MD. Tracking superparamagnetic iron oxide labeled monocytes in brain by high-field magnetic resonance imaging. J Neurosci Res 2003; 73:284-95. [PMID: 12868062 DOI: 10.1002/jnr.10693] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Inflammatory cells, most notably mononuclear phagocytes (MP; macrophages and microglia), play a critical role in brain homeostasis, repair and disease. One important event in cellular biodynamics is how MP move in and throughout the nervous system. Prior studies have focused principally on cell migration across the blood-brain barrier during neuroinflammatory processes with little work done on cell movement within the brain. During the past decade our laboratories have studied the role of MP in HIV-1-associated dementia (HAD). In HAD MP incite sustained glial inflammatory reactions causing significant neuronal damage. To extend these works we investigated cell movement in brain and its influence for disease in a novel co-registration system integrating neuropathology with high-field magnetic resonance imaging (MRI). Human monocytes labeled with superparamagnetic iron oxide particles were injected into the brain of severe combined immunodeficient (SCID) mice. MRI was recorded 1, 7, and 14 days after cell injection. MRI co-registered with histology verified that the MRI signal modification was due to the labeled cells. MRI showed human monocyte-derived macrophages along the injection site, the corpus callosum, the ventricular system and in other brain sites. These data support the idea that cell migration can be monitored in vivo and provides an opportunity to assess monocyte mobility in brain and its affects on neurodegenerative processes and notably HAD.
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Affiliation(s)
- Marina L Zelivyanskaya
- Center for Neurovirology and Neurodegenerative Disorders, University of Nebraska Medical Center, Omaha, Nebraska 68198-5215, USA
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218
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Roberts ES, Zandonatti MA, Watry DD, Madden LJ, Henriksen SJ, Taffe MA, Fox HS. Induction of pathogenic sets of genes in macrophages and neurons in NeuroAIDS. THE AMERICAN JOURNAL OF PATHOLOGY 2003; 162:2041-57. [PMID: 12759259 PMCID: PMC1868118 DOI: 10.1016/s0002-9440(10)64336-2] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/17/2003] [Indexed: 10/18/2022]
Abstract
The etiology of the central nervous system (CNS) alterations after human immunodeficiency virus (HIV) infection, such as dementia and encephalitis, remains unknown. We have used microarray analysis in a monkey model of neuroAIDS to identify 98 genes, many previously unrecognized in lentiviral CNS pathogenesis, whose expression is significantly up-regulated in the frontal lobe of simian immunodeficiency virus-infected brains. Further, through immunohistochemical illumination, distinct classes of genes were found whose protein products localized to infiltrating macrophages, endothelial cells and resident glia, such as CD163, Glut5, and ISG15. In addition we found proteins induced in cortical neurons (ie, cyclin D3, tissue transglutaminase, alpha1-antichymotrypsin, and STAT1), which have not previously been described as participating in simian immunodeficiency virus or HIV-related CNS pathology. This molecular phenotyping in the infected brains revealed pathways promoting entry of macrophages into the brain and their subsequent detrimental effects on neurons. These data support the hypothesis that in HIV-induced CNS disease products of activated macrophages and astrocytes lead to CNS dysfunction by directly damaging neurons, as well as by induction of altered gene and protein expression profiles in neurons themselves which are deleterious to their function.
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Affiliation(s)
- Eleanor S Roberts
- Department of Neuropharmacology, The Scripps Research Institute, La Jolla, California 92037, USA
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219
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Gupta N, Brown KE, Milam AH. Activated microglia in human retinitis pigmentosa, late-onset retinal degeneration, and age-related macular degeneration. Exp Eye Res 2003; 76:463-71. [PMID: 12634111 DOI: 10.1016/s0014-4835(02)00332-9] [Citation(s) in RCA: 414] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Many gaps exist in our knowledge of human retinal microglia in health and disease. We address the hypothesis that primary death of rod photoreceptors leads to activation of resident microglia in human retinas with retinitis pigmentosa (RP), late-onset retinal degeneration (L-ORD), or age-related macular degeneration (AMD). Regions of ongoing photoreceptor cell death were studied by immunocytochemistry with microglia- and other retinal cell-specific markers. In normal human retinas, quiescent microglia were small, stellate cells associated with inner retinal blood vessels. In retinas with RP, L-ORD, or AMD, numerous activated microglia were present in the outer nuclear layer in regions of ongoing rod cell death. These microglia were enlarged, amoeboid cells that contained rhodopsin-positive cytoplasmic inclusions. We conclude that activated microglia migrate to the outer nuclear layer and remove rod cell debris. In other central nervous system diseases such as stroke, activated microglia phagocytose debris from the primary injury and also secrete molecules that kill nearby normal neurons. By analogy with these diseases, we suggest that microglia activated by primary rod cell death may kill adjacent photoreceptors. Activated microglia may be a missing link in understanding why initial rod cell death in the human diseases RP, L-ORD, and AMD leads to death of the cones that are critical for high acuity daytime vision.
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Affiliation(s)
- Nisha Gupta
- Scheie Eye Institute, 51 North 39th Street, Philadelphia, PA 19104, USA
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220
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Albright AV, Soldan SS, González-Scarano F. Pathogenesis of human immunodeficiency virus-induced neurological disease. J Neurovirol 2003; 9:222-7. [PMID: 12707852 DOI: 10.1080/13550280390194073] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2003] [Revised: 01/13/2003] [Accepted: 01/20/2003] [Indexed: 10/20/2022]
Abstract
Infection of the central nervous system by the type 1 human immunodeficiency virus (HIV-1) commonly results in a number of neurological impairments known, in their most severe form, as HIV-associated dementia (HAD). The persistence of HIV encephalitis (HIVE), the pathological correlate of HAD, in spite of highly active antiretroviral therapy (HAART) underscores the importance of continued research focused on the neurobiology of HIV. To elucidate direct and indirect mechanisms of HIV neuropathogenesis, current investigation is focused on neuroinvasion, HIV-1-mediated mechanisms of neuronal damage and apoptosis, and compartmentalized evolution of virus in the brain. The aim of this review is to provide a selective overview of the most recent research on the neurobiology of HIV, adding only a brief introduction regarding established principles.
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Affiliation(s)
- Andrew V Albright
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-4283, USA
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221
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Babas T, Muñoz D, Mankowski JL, Tarwater PM, Clements JE, Zink MC. Role of microglial cells in selective replication of simian immunodeficiency virus genotypes in the brain. J Virol 2003; 77:208-16. [PMID: 12477826 PMCID: PMC140580 DOI: 10.1128/jvi.77.1.208-216.2003] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
An accelerated, consistent macaque simian immunodeficiency virus (SIV) model in which over 90% of pigtailed macaques (Macaca nemestrina) coinoculated with SIV/17E-Fr and SIV/DeltaB670 developed encephalitis was used to determine whether central nervous system (CNS) lesions are associated with the replication of specific genotypes in the brain and, more specifically, in the microglia. Ten of 11 inoculated macaques had severe (n = 3), moderate (n = 5), or mild (n = 2) encephalitis at 3 months postinoculation. To compare actively replicating viral genotypes in the CNS and in microglia with those in the periphery, the V1 region of the SIV envelope gene was amplified and sequenced from RNA extracted from basal ganglia, from microglial cells isolated from the brain, and from peripheral blood mononuclear cells (PBMC) isolated from blood at the time of death. To distinguish between actively replicating with latent viral genotypes in the CNS, viral genotypes in RNA and DNA from basal ganglia were compared. Two macrophage-tropic, neurovirulent viruses, SIV/17E-Fr and SIV/DeltaB670 Cl-2, predominated in the brain RNA of macaques with encephalitis, comprising 95% of the genotypes detected. The same two viral genotypes were present at the same frequencies in microglial cell RNA, suggesting that microglia are pivotal in the selective replication of neurovirulent viruses. There was a significantly greater number of viral genotypes in DNA than there were in RNA in the brain (P = 0.004), including those of both the macrophage- and lymphocyte-tropic viral strains. Furthermore, significantly fewer viral genotypes were detected in brain RNA than in PBMC RNA at the time of death (P = 0.004) and the viral strain that predominated in the brain frequently was different from that which predominated in the PBMC of the same animal. These data suggest that many viral genotypes enter the brain, but only a limited subset of macrophage-tropic, neurovirulent viruses replicate terminally in the brains of macaques with encephalitis. They further suggest that the selection of macrophage-tropic, neurovirulent viruses occurs not at the level of the blood-brain barrier but at a stage after virus entry and that microglial cells may play an important role in that selection process.
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Affiliation(s)
- Tahar Babas
- Department of Comparative Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
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222
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Williams K, Schwartz A, Corey S, Orandle M, Kennedy W, Thompson B, Alvarez X, Brown C, Gartner S, Lackner A. Proliferating cellular nuclear antigen expression as a marker of perivascular macrophages in simian immunodeficiency virus encephalitis. THE AMERICAN JOURNAL OF PATHOLOGY 2002; 161:575-85. [PMID: 12163382 PMCID: PMC1850726 DOI: 10.1016/s0002-9440(10)64213-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Brain perivascular macrophages are a major target of simian immunodeficiency virus (SIV) infection in rhesus macaques and HIV infection in humans. Perivascular macrophages are distinct from parenchymal microglia in their location, morphology, expression of myeloid markers, and turnover in the CNS. In contrast to parenchymal microglia, perivascular macrophages are continuously repopulated by blood monocytes, which undergo maturation to macrophages on entering the central nervous system (CNS). We studied differences in monocyte/macrophages in vivo that might account for preferential infection of perivascular macrophages by SIV. In situ hybridization for SIV and proliferating cellular nuclear antigen (PCNA) immunohistochemistry demonstrated that SIV-infected and PCNA-positive cells were predominantly found in perivascular cuffs of viremic animals and in histopathological lesions that characterize SIV encephalitis (SIVE) in animals with AIDS. Multilabel techniques including double-label immunohistochemistry and combined in situ hybridization and immunofluorescence confocal microscopy revealed numerous infected perivascular macrophages that were PCNA-positive. Outside the CNS, SIV-infected, PCNA-expressing macrophage subpopulations were found in the small intestine and lung of animals with AIDS. While PCNA is used as a marker of cell proliferation it is also strongly expressed in non-dividing cells undergoing DNA synthesis and repair. Therefore, more specific markers for cell proliferation including Ki-67, topoisomerase IIalpha, and bromodeoxyuridine (BrdU) incorporation were used which indicated that PCNA-positive cells within SIVE lesions were not proliferating. These observations are consistent with perivascular macrophages as terminally differentiated, non-dividing cells and underscores biological differences that could potentially define mechanisms of preferential, productive infection of perivascular macrophages in the rhesus macaque model of neuroAIDS. These studies suggest that within CNS and non-CNS tissues there exist subpopulations of macrophages that are SIV-infected and express PCNA.
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Affiliation(s)
- Kenneth Williams
- Department of Medicine, Harvard Medical School, Division of Viral Pathogenesis, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA.
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