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C S Reiss

Publications and source records attributed to C S Reiss.

At least 37 records · Page 2Linked to original sources

Interferon-gamma induced type I nitric oxide synthase activity inhibits viral replication in neurons.

Type I NOS expression increases in OB neurons during VSV infection. Immunocytochemical staining of NB41A3 cells indicates constitutive expression of interferon (IFN)-gamma receptor and type I NOS. IFN-gamma treatment of NB41A3 cells increased NO production and type I NOS protein. In vitro replication of VSV, polio virus type I, and Herpes Simplex virus type I (HSV-1) is significantly inhibited by IFN-gamma induced type I NOS and antagonized by NOS inhibitors. In contrast, while IFN-gamma treatment inhibited influenza and Sindbis virus replication, a different pathway(s) was involved. The isoform-selective NOS inhibitor. 7-nitroindazole (7NI) was used to treat mice, resulting in a 10-fold higher titer of virus in brain homogenates, and abrogated the recovery-promoting effect of interleukin-12 treatment. Thus, IFN-gamma induced type I NOS activity may play an important role in host immunity against neurotropic viral infections.

Animals↗

Host immune response to vesicular stomatitis virus infection of the central nervous system in C57BL/6 mice.

In this report, the kinetics of cellular inflammatory changes in the brain of vesicular stomatitis virus (VSV)-infected C57BL/6 (B6) mice was determined. The behavior and survival rate of infected B6 were carefully monitored each day. Infectious viral titers and VSV antigen distribution were determined at several time points during the course of infection. Strong activation of both astrocytes and microglia was observed after VSV infection. Induction of type II nitric oxide synthase (iNOS) was detected in activated microglia in the olfactory bulb (OB) starting at day 4 postinfection. Induced expression of major histocompatibility complex (MHC) molecules and rapid infiltration of both T cells and natural killer (NK) cells were detected in the VSV-infected CNS. Collectively, these data indicate that the response to CNS infection in B6 mice, which is often primarily Th1 in characteristics, is comparable to BALB/c mice, a strain that often shows a Th2-dominated immune response.

Animals↗

IL-12 promotes enhanced recovery from vesicular stomatitis virus infection of the central nervous system.

To investigate the role of a cytokine in host defense against the vesicular stomatitis virus (VSV) infection of the central nervous system (CNS), IL-12 was injected i.p. into groups of 10 BALB/c mice on days -1, 0, 1, 2, and 3 postinfection. Four days postinfection, mice were examined. IL-12 strongly enhanced immunity to VSV infection in the CNS as demonstrated by 1) decreased VSV titers in brain homogenate of IL-12-injected mice compared with those of controls; 2) increased expression of inducible nitric oxide synthase in the CNS; 3) enhanced expression of both MHC class I and class II Ags in the CNS; 4) increased T cell infiltration in the CNS, especially in the olfactory bulb; and 5) diminished VSV-induced apoptosis in olfactory bulb. No detrimental effect was observed even with the 200 ng/mouse dose of IL-12. Protective effects of IL-12 were dose dependent. Collectively, these results demonstrate that exogenously added IL-12, even when injected peripherally, significantly enhances recovery from VSV infection of the CNS.

Animals↗

The earliest events in vesicular stomatitis virus infection of the murine olfactory neuroepithelium and entry of the central nervous system.

After intranasal instillation of mice with vesicular stomatitis virus (VSV), olfactory receptor neurons are infected. By 12 to 24 hr postinfection, VSV antigens are observed in adjoining supporting and basal cells and in other structures of the olfactory epithelium and lamina propria. Peripheral deafferentation of the olfactory epithelium with Triton X-100 or bilateral surgical bulbectomy does not prevent spread of VSV to the central nervous system (CNS); the route of spread differs considerably from the route taken when the olfactory nerve is intact. In contrast to rabies virus and HSV-1, VSV does not use the trigeminal nerve for entry into the brain, as the trigeminal ganglion remains virus-free following intranasal infection. These results indicate that VSV has a strong tropism for olfactory receptor cells, using them for entry into the CNS. Both retrograde and anterograde transneuronal and nonneuronal (ependymal cells and cerebrospinal fluid) pathways are utilized by VSV within the CNS.

Animals↗

Processing of a viral glycoprotein in the endoplasmic reticulum for class II presentation.

Endogenous processing of viral glycoproteins for presentation to CD4+T cells is a poorly investigated aspect of antigen processing and presentation. This pathway may involve not only pathogens, but also self proteins, and may thus be involved in self-tolerance. We have characterized the processing of the endoplasmic reticulum-restricted glycoprotein (G) of vesicular stomatitis virus, termed poison tail (Gpt), biochemically and enzymatically, and by T cell recognition assays. Expressed with a vaccinia vector, Gpt remains endoglycosidase H-sensitive and does not mature to endoglycosidase D sensitivity. The protein is degraded in the ER with a T1/2 of 4 h. Gpt peptides are not secreted since Gpt-infected cells are unable to sensitize uninfected antigen-presenting cells in an innocent bystander assay. Using flow cytometry, Gpt is undetectable on the plasma membrane; in contrast, wild-type G is readily found on the surface or secreted into the milieu as soluble G following infection of A20 cells with a vaccinia recombinant expressing G. The degradation of Gpt is sensitive to the thiol reagent diamide and occurs optimally at physiological pH. A series of proteolytic inhibitors were tested: 3,4-dichloroisocoumarin and 1-chloro-3-tosylamido-7-amino-2-heptanone inhibited degradation, which suggests the involvement of a serine protease. The degradation does not require transport to the Golgi complex, and is not sensitive to a variety of lysosomotropic agents. We show that the degradation products include the immunogenic epitopes recognized by a panel of T cell clones and hybridomas.

Animals↗

Vesicular stomatitis virus infection of the central nervous system activates both innate and acquired immunity.

Vesicular stomatitis virus (VSV) causes acute infection of the central nervous system (CNS) when intranasally applied. We have examined cellular inflammatory changes in the CNS following VSV infection. As early as 1 day postinfection (p.i.), astrocytes were activated in the olfactory bulb (OB). This was followed by activation of microglia, first observed in the OB at day 3 p.i. Expression of inducible nitric oxide synthase was observed in activated microglia in the OB at day 3 p.i., and increased inducible nitric oxide synthase expression coincided with decreased virus titers in tissue homogenates. Expression of major histocompatibility complex (MHC) class I molecules on astrocytes and microglial, endothelial, and ependymal cells was also rapidly induced and followed by induced expression of MHC class II molecules on astrocytes and microglial and endothelial cells. Consistent with the pattern of viral dissemination, MHC molecules were expressed temporally from the rostral-to-caudal direction. Infiltration of CD8+ cells was observed as early as 1 day p.i. in the OB. CD4+ cells were detected in the OB at day 4 p.i. Increasing T-cell infiltration coincided with decreased virus titers. In contrast, B-cell infiltration of the CNS was not detected until day 14 p.i., after the virus was cleared and mice were showing behavioral signs of recovery. Breakdown of the blood-brain barrier was detected beginning at day 6 p.i., was most severe at day 8 p.i., and was followed by full recovery. Collectively, these data show that both innate immunity (production of nitric oxide) and acquired immunity (expression of MHC molecules and T-cell infiltration) are activated following VSV infection in the CNS.

Amino Acid Oxidoreductases↗

Inhibition of vesicular stomatitis virus infection by nitric oxide.

Inhibitory effects of nitric oxide (NO) on vesicular stomatitis virus (VSV) infection were investigated by using a VSV-susceptible mouse neuroblastoma cell line, NB41A3. Productive VSV infection of NB41A3 cells was significantly inhibited by an organic NO donor, S-nitro-N-acetylpenicillamine (SNAP), while the control compound N-acetylpenicillamine (NAP) had no effect. Survival rate of VSV-infected cells was greatly increased by the treatment with SNAP, while the NAP treatment did not have any effect. Adding SNAP 30 min prior to infection resulted in complete inhibition of viral production when a low multiplicity of infection (MOI) was used. Substantial inhibition of viral production was also obtained with treating cells 6 h earlier before infection with a higher MOI. Activating the neuronal NO synthase by treating cells with N-methyl-D-aspartate (NMDA) led to significant inhibition of viral production by cells infected at the three doses of virus tested (MOIs of 0.1, 1, and 5). The inhibitory effect of NMDA on viral infection was totally blocked by the NO synthase inhibitor N-methyl-L-arginine. However, adding hemoglobin, a strong NO-binding protein and thus an inactivator of NO activity, did not reverse the NMDA-induced inhibition of viral production, suggesting that NO might exert its antiviral effects inside the NO-producing cells. Collectively, these data support the anti-VSV effects of NO, which might be one of the important factors of natural immunity in controlling the initial stages of VSV infection in the central nervous system.

Amino Acid Oxidoreductases↗

Pathogenesis of murine encephalitis limited by defective interfering particles. An immunohistochemical study.

To determine whether defective interfering (DI) particles alter viral encephalitis BALB/c mice were inoculated intranasally with standard vesicular stomatitis virus (VSV) and its DI particles. Addition of 10(7) PFU equivalents of DI particles to 10(5) PFU of VSV reduced morbidity but did not delay disease onset. Less mortality was also observed. When 10(3) PFU equivalents of DI particles or UV-irradiated DI particles were substituted, these effects were absent. Attempts to correlate mortality with virus recovered from the brain could not be made due to considerable variations in the few surviving mice. Immunohistochemical analysis obtained from 121 mice showed that inoculation of DI particles limited the specific pathways of VSV antigen dissemination within the central nervous system, and new pathways were not substituted. In the group of mice with reduced mortality due to DI particles, at day 4 post inoculation VSV antigen was limited to the outer layers of the glomeruli of the olfactory bulb and to the accessory olfactory bulb, whereas there was deeper invasion of the olfactory bulb and olfactory ventricular system with mice infected with standard VSV alone. Correlation between mortality and extent of invasion became more difficult to make from 8 days on, when VSV antigens were found in discrete areas of the brain. By 12 days, few surviving mice contained any detectable VSV antigen in their brains. These results demonstrate that DI particles have potential as therapeutic agents. Also, mortality resulting from VSV-induced encephalitis, although poorly understood, may be determined very early, possibly while the virus is replicating at the site of inoculation.

Animals↗

Distribution of vesicular stomatitis virus proteins in the brains of BALB/c mice following intranasal inoculation: an immunohistochemical analysis.

Earlier studies have shown that intranasal instillation of vesicular stomatitis virus (VSV), a negative-sense RNA virus, in mice and rats can result in infection of the brain, hind-limb paralysis and death. Using an antiserum directed against VSV proteins, we sought to determine the potential neuronal and non-neuronal pathways VSV utilize, for central nervous system dissemination in BALB/c mice. Within 12 h following intranasal inoculation of VSV, VSV antigen could be detected in the olfactory nerve layer of the ipsilateral olfactory bulb. Within 3-4 days post-inoculation (p.i.), VSV had disseminated into the glomeruli of the olfactory bulb as well as the anterior olfactory nuclei that were ipsilateral to the VSV instillation. Within the glomeruli, VSV antigen was more prevalent in the granule cells than in the mitral cells. Correspondingly, the lateral olfactory tract, where axons of mitral cells course, remained VSV negative throughout 7 days p.i. By 7 days p.i., viral proteins were detected in several additional regions extending to the brainstem. These included regions involved in theta-rhythm generation during exploration and REM sleep, i.e. the septal nuclei, the supramammillary body, and the hippocampal formation, as well as the amygdaloid complex and brainstem neuromodulatory centers, such as the dorsal raphé and locus coeruleus. Structures abutting the ventricular surfaces, such as the dorsal cochlear nucleus, were also labeled. Tracts immunoreactive to VSV included the dorsal tegmental tract, fascia retroflexus, Probst tract, and mesencephalic tract of the trigeminal motor nerve. Besides the lateral olfactory tract, tracts that remained VSV negative included the anterior commissure, the corpus callosum and the mammillary peduncle. The pattern of VSV immunoreactivity supports the idea that following infection of the olfactory bulb glomeruli, VSV spreads via both ventricular surfaces and retrograde transport within axons of neuromodulatory transmitter systems innervating the olfactory bulb. Conversely, regions exhibiting low levels of VSV antigen are not likely to be involved in VSV dissemination. In particular, the paucity of VSV antigen in some of the terminal fields of neuromodulatory systems indicate that anterograde transport is more selective than retrograde transport. Surprisingly, the principal neurons of the olfactory glomeruli, thalamus, cerebral cortex and the hippocampus, all of which use L-glutamate as the excitatory neurotransmitter, are much less involved in viral dissemination.

Administration, Intranasal↗

Inhibition of vesicular stomatitis virus RNA synthesis by protein hyperphosphorylation.

Vesicular stomatitis virus (VSV) RNA synthesis requires the template nucleocapsid, the polymerase (L) protein, and the cofactor phosphorylated (P/NS) protein. To determine whether the degree of phosphorylation regulated VSV RNA synthesis, infected Chinese hamster ovary cells were treated with okadaic acid (OKA), a serine/threonine phosphatase inhibitor. OKA reduced viral penetration and uncoating but had little or no effect on primary transcription or viral protein synthesis. However, approximately 80% of total viral RNA synthesis was inhibited when 2 microM or more OKA was added to infected cells after viral uncoating had taken place. Analysis of proteins and RNA species in infected cells labeled with 32P showed that OKA led to hyperphosphorylation of two viral phosphoproteins, the P/NS protein and matrix protein (M), resulting in inhibition of full-length RNA synthesis and subsequent secondary transcription. Pulse-chase experiments demonstrated that the hyperphosphorylated P/NS species was converted rapidly from the less phosphorylated form. Hyperphosphorylated P/NS as well as the less phosphorylated form, but not M, were found to be associated with nucleocapsids isolated from cytoplasmic extracts. These results suggest that phosphorylation played an important role in the regulation between viral transcription and viral RNA replication as well as the turning off of RNA replication. Thus, phosphatase inhibitors promise to be a valuable tool for dissecting the regulatory mechanisms involving phosphorylated viral proteins.

Animals↗

Lymphokine expression profile of resting and stimulated CD4+ CTL clones specific for the glycoprotein of vesicular stomatitis virus.

A panel of long-term murine T lymphocyte clones specific for the glycoprotein of vesicular stomatitis virus (VSV) in association with either H-2I-Ad or I-E(d) was tested for the production of cytokines in both resting and poststimulation states using both in situ hybridization and bioassay. All but one of the clones showed antigen-specific cytolytic activity in a 4-hr 51Cr release assay. Unexpectedly, the clones did not appear to be typical Th1 cells. Five of these T cell clones produced both IL-2 and IFN-gamma but not IL-4 after stimulation with either phorbol 12-myristate 13-acetate (PMA) or concanavalin A (Con A). Some clones constitutively expressed mRNA for IL-2 and INF-gamma. The proliferation of these clones was factor independent, suggesting an autocrine growth mechanism. Three clones produced variable levels of IL-4 mRNA and some, to significant quantities, of IL-2 mRNA. One cytolytic clone produced neither IL-2 nor IL-4 mRNA to detectable levels, although mRNA for IFN-gamma was observed. A noncytolytic, Ag-specific clone produced IL-6, tumor necrosis factor (TNF), and lymphotoxin (LT), but no IL-2, IL-4, or IFN-gamma mRNA. There was a strong quantitative correlation between the expression of IL-2-, INF-gamma-, and LT-specific mRNAs by the clones. All the T cell clones tested which secreted INF-gamma and LT expressed no measurable IL-4 mRNA. We examined expression of several other genes in the panel of clones. These included TNF, met-enkephalin (met-enk), IL-1, and IL-6. IL-1 m-RNA synthesis was not observed in any of the T cell clones. Almost all clones produced TNF mRNA. Parallel bioassays showed that secreted IL-2/IL-4 activity levels and mRNA levels correlated well for all clones. Thus, we observed a great degree of heterogeneity among CD4+ cytolytic T lymphocyte clones.

Animals↗

The current status of viral immunology.

Many aspects of viral immunity, ranging from the molecular and cellular studies of the interaction between viruses and host cells in vitro and the crystalline structures of the MHC and peptides, to the regulation of pathogenesis in experimental animals and humans were discussed at a recent meeting.

Allergy and Immunology↗

Central neuropathogenesis of vesicular stomatitis virus infection of immunodeficient mice.

To determine whether central neuropathogenesis associated with vesicular stomatitis virus (VSV) infection is regulated by T cells, we have examined the effects of intranasal infection of mice lacking T cells. The mice examined were of two kinds: (i) thymus-deficient BALB/c nu/nu nice and (ii) BALB/c mice experimentally depleted of T cells by systemic infusions of a monoclonal antibody to the CD4 or CD8 cell surface molecules. These mice were infected intranasally with a single dose of replication-competent VSV. Brain tissue homogenates were analyzed for the presence of infectious virus. For each population of mice, infection-related mortality was assessed. In histological sections of brain, the distribution of viral antigens (Ags) was examined by immunocytochemistry. We found that recovery of infectious virus from homogenates of tissues obtained from athymic nu/nu animals was more than 10 times greater than that from samples from their euthymic littermates. With a single exception in a BALB/c nu/nu mouse, virus was not isolated from the spleen when it was administered intranasally. In these experimental infections, athymic mice succumbed 1 to 2 days before their euthymic littermates. A dose of virus that resulted in half of the nu/+ survival rate was uniformly lethal to nu/nu mice. In experiments with BALB/c mice depleted of either CD4+ or CD8+ T cells by in vivo antibody treatment, histological analysis revealed an increase in viral Ag distribution in comparison with control (medium-infused) infected mice. Necrosis and inflammation paralleled the extent of viral Ag expression. Viral Ags were detected in discrete areas that usually remain uninfected in immunocompetent mice. These areas include the neocortex and caudate putamen nuclei, the piriform cortex, and the lateral olfactory tract. Neuronal loss and necrosis were consistently found in the olfactory bulb and the horizontal/vertical band of Broca. In some of the T-cell depleted mice, necrosis was also evident in the hippocampus, fimbria, mammillary bodies, and hypothalamic nuclei. In the brain stem, perivascular cuffing was evident, but with little necrosis. Collectively, these data suggest that CD4+ and CD8+ T cells make only a minor contribution to the development of histopathology but rather function together to limit viral replication and transsynaptic or ventricular spread of virus, thus promoting recovery. The primary effectors of histopathology appear to be related more to the cytopathologic nature of the virus infection and non-T-cell-mediated mechanisms.

Animals↗

Newly synthesized class II MHC chains are required for VSV G presentation to CTL clones.

Mechanisms of antigen processing and presentation to thymus-derived lymphocytes have been under intense study for several years, focusing on both Class I-restricted antigen presentation and Class II-MHC restricted responses. The studies described here examine the processing and presentation of exogenously provided soluble glycoprotein of the vesicular stomatitis virus and as well as newly synthesized viral glycoprotein. Evidence is provided that newly synthesized Class II MHC chains are required for cell surface expression of processed glycoprotein determinants irrespective of the origin of the viral antigen. Inhibitors of distinct cellular processes, including ammonium chloride, emetine, and Brefeldin A, have been used to dissect the pathways utilized.

Ammonium Chloride↗

Altered histopathology in protein-deprived mice during Sendai virus pneumonia: evidence for delayed inflammatory response and recovery.

The morphology of the lungs and airway during the course of respiratory infection caused by Sendai virus was examined in normal (20% protein diet) and malnourished (2% protein diet) BALB/c mice. Mortality in normal Sendai-infected mice was 0 compared with 71% in the infected malnourished group. Virus was isolated until day 6 in normally fed mice and until day 9 in the malnourished group. Pulmonary inflammation was largely mononuclear and began in the normally nourished animals on day 3, peaked at day 6, and reverted almost to normal by 30 days. In the malnourished group, inflammation was delayed by about 1 day and fell further behind during the first week. It peaked 10-13 days after infection and was still present with little resolution by day 30. These findings may have relevance to the high mortality of acute respiratory diseases in children of the developing world.

Acute Disease↗

Epstein-Barr virus-encoded small RNAs (EBERs) do not modulate interferon effects in infected lymphocytes.

The recent derivation of otherwise isogenic Epstein-Barr virus (EBV) recombinants carrying or lacking the EBV small RNA (EBER) genes enabled us to test whether EBERs are similar to adenovirus VA RNAs in modulating interferon (IFN) effects on virus infection. EBER-positive and -negative EBV recombinants did not differ in their sensitivity to alpha interferon (IFN-alpha)- or IFN-gamma-mediated inhibition of lymphocyte growth transformation. In addition, EBERs did not decrease the inhibitory effects of IFN on vesicular stomatitis virus replication in EBV-transformed lymphocytes. EBER deletion also did not render EBV-transformed B lymphocytes susceptible to an IFN effect on cell proliferation or EBV replication.

B-Lymphocytes↗

Replication-defective viruses modulate immune responses.

By immunizing inbred mice with purified replication-competent, defective virus particles, or an admixture of the two, differential effects on the cellular immune system have been uncovered. Defective virus, exemplified by the vesicular stomatitis virus (VSV) defective interfering particle (DI 0.33), induced in BALB/c mice low levels of proliferating, IL-2 secreting, and cytolytic Ag-specific T lymphocytes. This was not caused by a dominant suppressor cell response, or by a failure to stimulate lymphokine-secreting cells, but appeared to reflect a reduced efficiency of priming as compared with standard virus. Mice primed with a mixture of wt and DI virus showed reduced proliferation compared with mice primed with wt virus. When histocompatible target cells were sensitized by pure DI particles, they were neither recognized nor lysed by CD8+ CTL. Cells co-infected with wt and DI particles were not as readily lysed by CD8+ CTL as cells infected by VSV alone. The extent of this reduction was dependent on the concentration of DI particles. This suggests that DI particles may have prevented the proper presentation of endogenously synthesized Ag for recognition by CD8+ CTL. Metabolic labeling studies indicated that the presence of DI particles suppressed the synthesis of viral proteins in dually infected cells. However, CD4+ T lymphocyte clones recognized and efficiently lysed histocompatible Ia+ cells infected with DI particles alone or co-infected with replication-competent and defective virus.

Animals↗

Sendai virus infection of normal and protein malnourished mice: response of airway leukocytes to infection.

We examined the cells recovered by bronchoalveolar lavage (BAL) during the course of respiratory infection caused by Sendai virus in normal (20% protein diet) and malnourished (2% protein diet) mice. As in our previous experiments, mortality in normal mice was 32% in comparison with 87% in the malnourished group. Virus was isolated until the 5th day in normally fed mice and until the 9th day in the malnourished group. BAL fluids contained 97% macrophages before infection in both groups. During infection there was a progressive lymphocyte response, reaching a peak of 60-70% on day 5 in the normal mice and on days 7-9 in the malnourished group. Subtyping of BAL cells by flow cytometry indicated that in uninfected animals lymphocytes were largely CD4-bearing. On days 3 and 5 post-infection most mononuclear cells were Thy 1.2-positive, but lacked both CD4 and CD8 markers and were therefore probably natural killer cells. Beginning on day 5, in both diet groups CD8-positive cells rose to become the predominant subset. In the 20% protein diet group, CD8-positive cells reached a maximum of 60% on day 7, whereas in the 2% protein diet group this level was not reached until day 9. These results were consistent in three separate experiments. In malnourished mice the delayed appearance of CD8-bearing cells in the airway may contribute to the higher mortality and delayed virus clearance during Sendai virus infection.

Animals↗