In Vivo Viral Control in a HLA-B*35:01 Homozygous Individual after the Vaccine-induced Response to a Well-defined, HIV Gag-derived HLA-B*35 CTL Epitope

Focal hypoxia in the pre-Bötzinger complex (pre-BötC) in vivo elicits excitation of inspiratory motor output by modifying the patterning and timing of phrenic bursts. Hypoxia, however, has been reported to enhance glutamate release in some regions of the brain, including the medullary ventral respiratory column; thus the pre-BötC–mediated hypoxic respiratory excitation may result from, or be influenced by, hypoxia-induced activation of ionotropic glutamate [i.e., excitatory amino acid (EAA)] receptors. To test this possibility, the effects of focal pre-BötC hypoxia [induced by sodium cyanide (NaCN)] were examined before and after blockade of ionotropic EAA receptors [using kynurenic acid (KYN)] in this region in chloralose-anesthetized, vagotomized, mechanically ventilated cats. Before blockade of ionotropic EAA receptors, unilateral microinjection of NaCN (1 mM; 10–20 nl) into the pre-BötC produced either phasic or tonic excitation of phrenic nerve discharge. Unilateral microinjection of KYN (50–100 mM; 40 nl) decreased the amplitude and frequency of basal phrenic nerve discharge; however, subsequent microinjection of NaCN, but not dl-homocysteic acid (DLH, a glutamate analog), still produced excitation of phrenic motor output. Under these conditions, the NaCN-induced excitation included frequency modulation (FM) of phasic phrenic bursts, and in many cases, augmented and/or fractionated phrenic bursts. These findings show that the hypoxia-sensing function of the in vivo pre-BötC, which produces excitation of phrenic nerve discharge, is not dependent on activation of ionotropic glutamate receptors, but ionotropic glutamate receptor activation may modify the expression of the focal hypoxia-induced response. Thus these findings provide additional support to the concept of intrinsic hypoxic sensitivity of the pre-BötC.

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The characteristics of the HIV-1 Env glycoprotein contribute to viral pathogenesis

10.1101/2021.07.07.451566 ◽

2021 ◽

Author(s):

Silvia Perez-Yanes ◽

Maria Pernas ◽

Silvia Marfil ◽

Romina Cabrera-Rodríguez ◽

Raquel Ortiz ◽

...

Keyword(s):

Functional Characteristic ◽

Elite Controllers ◽

Clinical Progression ◽

Viral Control ◽

Clinical Phenotypes ◽

Viral Loads ◽

Variable Contribution ◽

Gp120 Subunit ◽

Hiv 1

The understanding of HIV-1 pathogenesis and clinical progression is incomplete because of the variable contribution of host, immune and viral factors. The involvement of viral factors has been investigated in extreme clinical phenotypes from rapid progressors to long-term non-progressors (LTNPs). Among HIV-1 proteins, the envelope glycoprotein complex (Env) has concentrated many studies for its important role in the immune response and in the first steps of viral replication. In this study, we analyzed the contribution of 41 Envs from 24 patients with different clinical progression rates and viral loads (VLs), LTNP-Elite Controllers (LTNP-ECs); Viremic LTNPs (vLTNPs), and non-controller’s individuals contemporary to LTNPs or recent, named Old and Modern progressors. We analyzed the Env expression, the fusion and cell-to-cell transfer capacities as well as viral infectivity. The sequence and phylogenetic analysis of Envs were also performed. In every functional characteristic, the Envs from subjects with viral control (LTNP-ECs and vLTNPs) showed significant lower performance compared to those from the progressor individuals (Old and Modern). Regarding sequence analysis, the variable loops of the gp120 subunit of the Env (i.e., V2, V4 and mainly V5) of the progressor individuals showed longer and more glycosylated sequences than controller subjects. Therefore, HIV-1 Envs presenting poor viral functions and shorter sequences were associated with viremic control and the non-progressor clinical phenotype, whereas functional Envs were associated with the lack of virological control and progressor clinical phenotypes. These correlations support the central role of Env genotypic and phenotypic characteristics in the in vivo HIV-1 infection and pathogenesis.

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Effects of norepinephrine upon superficial layer neurons in the superior colliculus of the hamster: In vitro studies

Visual Neuroscience ◽

10.1017/s0952523899163156 ◽

1999 ◽

Vol 16 (3) ◽

pp. 557-570 ◽

Cited By ~ 9

Author(s):

HONGJING TAN ◽

RICHARD D. MOONEY ◽

ROBERT W. RHOADES

Keyword(s):

Superior Colliculus ◽

Optic Tract ◽

Reversal Potential ◽

Outward Current ◽

Input Resistance ◽

Superficial Layer ◽

Membrane Properties ◽

Induced Response

Intracellular recording techniques were used to evaluate the effects of norepinephrine (NE) on the membrane properties of superficial layer (stratum griseum superficiale and stratum opticum) superior colliculus (SC) cells. Of the 207 cells tested, 44.4% (N = 92) were hyperpolarized by ≥3 mV and 8.7% (N = 18) were depolarized by ≥3 mV by application of NE. Hyperpolarization induced by NE was dose dependent (EC50 = 8.1 μM) and was associated with decreased input resistance and outward current which had a reversal potential of −94.0 mV. Depolarization was associated with a very slight rise in input resistance and had a reversal potential of −93.1 mV for the single cell tested. Pharmacologic experiments demonstrated that isoproterenol, dobutamine, and p-aminoclonidine all hyperpolarized SC cells. These results are consistent with the conclusion that NE-induced hyperpolarization of SC cells is mediated by both α2 and β1 adrenoceptors. The α1 adrenoceptor agonists, methoxamine and phenylephrine, depolarized 35% (6 of 17) of the SC cells tested by ≥3 mV. Most of the SC cells tested exhibited responses indicative of expression of more than one adrenoceptor. Application of p-aminoclonidine or dobutamine inhibited transsynaptic responses in SC cells evoked by electrical stimulation of optic tract axons. Inhibition of evoked responses by these agents was usually, but not invariably, associated with a hyperpolarization of the cell membrane and a reduction in depolarizing potentials evoked by application of glutamate. The present in vitro results are consistent with those of the companion in vivo study which suggested that NE-induced response suppression in superficial layer SC neurons was primarily postsynaptic and chiefly mediated by both α2 and β1 adrenoceptors.

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Effects of adrenomedullin and PAMP on adrenal catecholamine release in dogs

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1999.276.4.r1118 ◽

1999 ◽

Vol 276 (4) ◽

pp. R1118-R1124

Author(s):

Kimiya Masada ◽

Takahiro Nagayama ◽

Akio Hosokawa ◽

Makoto Yoshida ◽

Mizue Suzuki-Kusaba ◽

...

Keyword(s):

Nerve Stimulation ◽

Splanchnic Nerve ◽

Catecholamine Release ◽

Induced Response ◽

Dependent Manner ◽

Pentobarbital Sodium ◽

Anesthetized Dogs ◽

Dose Dependent ◽

Splanchnic Nerve Stimulation

We examined the effects of proadrenomedullin-derived peptides on the release of adrenal catecholamines in response to cholinergic stimuli in pentobarbital sodium-anesthetized dogs. Drugs were administered into the adrenal gland through the phrenicoabdominal artery. Splanchnic nerve stimulation (1, 2, and 3 Hz) and ACh injection (0.75, 1.5, and 3 μg) produced frequency- or dose-dependent increases in adrenal catecholamine output. These responses were unaffected by infusion of adrenomedullin (1, 3, and 10 ng ⋅ kg−1 ⋅ min−1) or its selective antagonist adrenomedullin-(22—52) (5, 15, and 50 ng ⋅ kg−1 ⋅ min−1). Proadrenomedullin NH2-terminal 20 peptide (PAMP; 5, 15, and 50 ng ⋅ kg−1 ⋅ min−1) suppressed both the splanchnic nerve stimulation- and ACh-induced increases in catecholamine output in a dose-dependent manner. PAMP also suppressed the catecholamine release responses to the nicotinic agonist 1,1-dimethyl-4-phenylpiperazinium (0.5, 1, and 2 μg) and to muscarine (0.5, 1, and 2 μg), although the muscarine-induced response was relatively resistant to PAMP. These results suggest that PAMP, but not adrenomedullin, can act as an inhibitory regulator of adrenal catecholamine release in vivo.

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Odor-Driven Activity in the Olfactory Cortex of an In Vitro Isolated Guinea Pig Whole Brain With Olfactory Epithelium

Journal of Neurophysiology ◽

10.1152/jn.01366.2005 ◽

2007 ◽

Vol 97 (1) ◽

pp. 670-679 ◽

Cited By ~ 17

Author(s):

Takahiro Ishikawa ◽

Takaaki Sato ◽

Akira Shimizu ◽

Ken-Ichiro Tsutsui ◽

Marco de Curtis ◽

...

Keyword(s):

Guinea Pig ◽

Olfactory Epithelium ◽

Afferent Input ◽

Initial Component ◽

Induced Response ◽

Activity Data ◽

Olfactory Neural Network ◽

The Brain

We developed a new technique to isolate a whole guinea pig brain with an intact olfactory epithelium (OE) that enables us to access the ventral surface of the brain including olfactory areas with ease during natural odor stimulation. We applied odorants to OE and confirmed that odor-induced local field potentials (LFPs) could be induced in olfactory areas. In the olfactory bulb (OB) and the piriform cortex (PC), odor-induced LFPs consisted of a phasic initial component followed by a fast activity oscillation in the beta range (20 Hz). To understand the neural mechanisms of odor-induced responses especially in the anterior PC, we analyzed odor-induced LFPs, together with unit activity data. We confirmed that the initial component of odor-induced response has a characteristic temporal pattern, generated by a relatively weak direct afferent input, followed by an intra-cortical associative response, which was associated with a phasic inhibition. The beta oscillation might be formed by the repetition of these network activities. These electrophysiological data were consistent with the results of previous studies that used slice or in vivo preparations, suggesting that the olfactory neural network and activities of the brain are preserved in our new in vitro preparation. This study provides the basis for clarifying the sequence of neural activities underlying odor information processing in the brain in vitro following natural olfactory stimulation.

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TLR agonists activate HPV11 E7-pulsed DCs to promote a specific T cell response in a murine model

Veterinární Medicína ◽

10.17221/4438-vetmed ◽

2011 ◽

Vol 56 (No. 12) ◽

pp. 602-611 ◽

Cited By ~ 1

Author(s):

XH Mao ◽

XZ Chen ◽

WW Zhang ◽

JY Wang ◽

LF Liu ◽

...

Keyword(s):

T Cell ◽

Mouse Model ◽

Cytokine Production ◽

T Cell Response ◽

Antigenic Peptides ◽

Epitope Peptide ◽

Tlr Agonists ◽

Ctl Epitope ◽

Th1 Cytokine

: Some TLR agonists may up-regulate the activation of dendritic cells caused by viral antigenic peptides and antigen-specific cytotoxic T lymphocytes, which are crucial in HPV vaccine development. We investigated the ability of three TLR agonists, imiquimod, PIC and CpG, to stimulate the maturation of murine BM-DCs loaded with HPV11E7 CTL epitopes, and the subsequent effect on HPV-specific T cell responses and tumour protection in a C57BL/6 mouse model. We found that TLR agonists, mostly PIC and imiquimod, stimulated the maturation of BM-DCs pulsed with HPV11E7 CTL epitope peptide. In combination with the epitope peptide, the TLR agonists CPG and PIC augmented epitope-specific Th1 cytokine production in vivo, while imiquimod and CPG, but not PIC, enhanced Th1 cytokine production in vitro. However, we failed to observe in vivo CTL cytotoxicity and anti-tumour protection upon TLR ligation in our mouse model. Our results demonstrate that TLR agonists activate HPV11E7 CTL epitope pulsed BM-DCs to promote specific Th1 immunity in C57BL/6 mouse model, indicating the promise of TLR agonists as adjuvants for HPV epitope/DC-based multifaceted vaccines against HPV infections such as condyloma accuminatum.  

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Ionotropic excitatory amino acid receptors in pre-Bötzinger complex play a modulatory role in hypoxia-induced gasping in vivo

Journal of Applied Physiology ◽

10.1152/japplphysiol.01133.2003 ◽

2004 ◽

Vol 96 (5) ◽

pp. 1643-1650 ◽

Cited By ~ 11

Author(s):

Irene C. Solomon

Keyword(s):

Amino Acid ◽

Excitatory Amino Acid ◽

Respiratory Rhythm ◽

Receptor Activation ◽

Induced Response ◽

Brain Hypoxia ◽

Bötzinger Complex ◽

Before And After ◽

Additional Support

Activation of ionotropic excitatory amino acid (EAA) receptors in pre-Bötzinger complex (pre-BötC) not only influences the eupneic pattern of phrenic motor output but also modifies hypoxia-induced gasping in vivo by increasing gasp frequency. Although ionotropic EAA receptor activation in this region appears to be required for the generation of eupneic breathing, it remains to be determined whether similar activation is necessary for the production and/or expression of hypoxia-induced gasping. Therefore, we examined the effects of severe brain hypoxia before and after blockade of ionotropic EAA receptors in the pre-BötC in eight chloralose-anesthetized, deafferented, mechanically ventilated cats. In each experiment, before blockade of ionotropic EAA receptors in the pre-BötC, severe brain hypoxia (6% O2 in a balance of N2 for 3-6 min) produced gasping. Although bilateral microinjection of the broad-spectrum ionotropic EAA receptor antagonist kynurenic acid (20-100 mM; 40 nl) into the pre-BötC eliminated basal phrenic nerve discharge, severe brain hypoxia still produced gasping. Under these conditions, however, the onset latency to gasping was increased ( P < 0.05), the number of gasps was reduced for the same duration of hypoxic gas exposure ( P < 0.05), the duration of gasps was prolonged ( P < 0.05), and the duration between gasps was increased ( P < 0.05). These findings demonstrate that hypoxia-induced gasping in vivo does not require activation of ionotropic EAA receptors in the pre-BötC, but ionotropic EAA receptor activation in this region may modify the expression of the hypoxia-induced response. The present findings also provide additional support for the pre-BötC as the primary locus of respiratory rhythm generation.

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A Limulus Antilipopolysaccharide Factor-Derived Peptide Exhibits a New Immunological Activity with Potential Applicability in Infectious Diseases

Clinical and Diagnostic Laboratory Immunology ◽

10.1128/cdli.7.4.669-675.2000 ◽

2000 ◽

Vol 7 (4) ◽

pp. 669-675 ◽

Cited By ~ 28

Author(s):

Maribel G. Vallespi ◽

Luis A. Glaria ◽

Osvaldo Reyes ◽

Hilda E. Garay ◽

Joel Ferrero ◽

...

Keyword(s):

Infectious Diseases ◽

Cyclic Peptides ◽

Mononuclear Cells ◽

Therapeutic Potential ◽

Peritoneal Macrophages ◽

Induced Response ◽

No Production ◽

Human Mononuclear Cells

ABSTRACT Previous studies have shown that cyclic peptides corresponding to residues 35 to 52 of the Limulus antilipopolysaccharide (anti-LPS) factor (LALF) bind and neutralize LPS-mediated in vitro and in vivo activities. Therapeutic approaches based on agents which bind and neutralize LPS activities are particularly attractive because these substances directly block the primary stimulus for the entire proinflammatory cytokine cascade. Here we describe new activities of the LALF31–52 peptide, other than its LPS binding ability. Surprisingly, supernatants from human mononuclear cells stimulated with the LALF peptide are able to induce in vitro antiviral effects on the Hep-2 cell line mediated by gamma interferon (IFN-γ) and IFN-α. Analysis of the effect of LALF31–52 on tumor necrosis factor (TNF) and nitric oxide (NO) production by LPS-stimulated peritoneal macrophages revealed that a pretreatment with the peptide decreased LPS-induced TNF production but did not affect NO generation. This indicates that the LALF peptide modifies the LPS-induced response. In a model in mice with peritoneal fulminating sepsis, LALF31–52 protected the mice when administered prophylactically, and this effect is related to reduced systemic TNF-α levels. This study demonstrates, for the first time, the anti-inflammatory properties of the LALF-derived peptide. These properties widen the spectrum of the therapeutic potential for this LALF-derived peptide and the molecules derived from it. These agents may be useful in the prophylaxis and therapy of viral and bacterial infectious diseases, as well as for septic shock.

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Photopheresis in HIV-1 Infected Patients (pt) using Benzoporphyrin Derivative (BPD-MA) Induces Apoptosis in CD4 Cells, Increases Intracellular Expression of Chemokines and Decreases HIV Infectivity and Viral Load.

Blood ◽

10.1182/blood.v104.11.3836.3836 ◽

2004 ◽

Vol 104 (11) ◽

pp. 3836-3836

Author(s):

Zale P. Bernstein ◽

Thomas Dougherty ◽

Stanley A. Schwartz ◽

Sandra Gollnick ◽

Carleton Stewart ◽

...

Keyword(s):

Viral Load ◽

Immune System ◽

Ex Vivo ◽

Light Exposure ◽

Area Under The Curve ◽

Additional Patient ◽

Viral Control ◽

Viral Loads ◽

Hiv 1

Abstract HIV is able to elude both cellular and humoral arms of the immune system; thereby making viral control difficult. Extra corporeal photochemotherapy (ECP) or photopheresis is an immunomodulatory therapy in which lymphocytes are reinfused into the host after exposure to a photoactive compound and ultraviolet A light. It is an effective therapeutic approach to several disorders of the immune system including acute and chronic graft-versus-host disease, scleroderma, and cutaneous T-cell lymphoma. This process may offer a novel approach to viral control with minimal or no toxicity. We initiated an ex vivo and subsequently a clinical pilot trial utilizing Benzoporphyrin Derivative as the photosensitive compound. Ex vivo dosing studies identified the minimum energy levels of light exposure and concentrations of BPD that eradicated both cell-free and cell-associated HIV-1 infectivity without destroying the virus particles or infected leukocytes. Leukocytes so treated remained viable. They did demonstrate altered cytokine and chemokine expression with apoptosis induced in a minority of CD4 but not CD8 positive cells. A pilot in vivo, 24 week clinical trial in seven HIV-1 infected patients (all were required, upon entry, to have viral loads of > 10,000) using the photopheresis parameters established above demonstrated that the treatment was well tolerated and beneficial. Three individuals who had rapidly rising viral loads prior to initiating therapy stabilized once treatment began. Two of which had a (sustained) greater than.5 log decrement and 5 had stable plasma viral loads (less than a.5 log increment or decrement) with varied effects on absolute CD4 and CD8 positive lymphocytes counts. One subject achieved a greater than 1 log decrement in HIV-1 plasma viral load also developed undetectable in vivo cell-free and cell-associated HIV-1 infectivity while demonstrating an increased in vitro lymphocyte mitogen stimulation index. Subsequently, under amended protocol 3 additional 12 month courses were administered to one additional patient and two of the previous enrollees. The area under the curve for viral load (viral load x # of weeks) for these ten courses of therapy showed a significant decrease from pre to post therapy (p 0.007). There were no significant changes in CD4 or CD8 numbers area under the curve (CD4 number # of weeks and CD8 number x # of weeks). None of the subjects developed an AIDS defining illness during the course of therapy nor were there any treatment associated toxicities. These studies suggest that ECP augments activity of various arms of the immune system without any significant toxicity and may be effective in controlling HIV replication. We have now instituted a Phase II study utilizing long-term photopheresis (twice monthly for 48 weeks) to further determine efficacy and mechanism of activity.

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Photopheresis in HIV-1 Infected Patients (Pt) Using Benzoporphyrin Derivative (BPD-MA) Induces Apoptosis in CD4 Cells, Increases Cytolytic T-Cell Activity, Intracellular Expression of Chemokines, and Decreases HIV Infectivity and Viral Load.

Blood ◽

10.1182/blood.v108.11.1257.1257 ◽

2006 ◽

Vol 108 (11) ◽

pp. 1257-1257

Author(s):

Zale P. Bernstein ◽

Thomas Dougherty ◽

Stanley Schwartz ◽

Sandra Gollnick ◽

Carleton Stewart ◽

...

Keyword(s):

Viral Load ◽

Immune System ◽

T Cell ◽

Ex Vivo ◽

Cell Activity ◽

Area Under The Curve ◽

Viral Control ◽

Viral Loads ◽

Hiv 1

Abstract HIV is able to elude both cellular and humoral arms of the immune system; thereby making viral control difficult. Extra corporeal photochemotherapy (ECP) or photopheresis is an immunomodulatory therapy in which lymphocytes are reinfused into the host after exposure to a photoactive compound and ultraviolet A light. It is an effective therapeutic approach to several disorders of the immune system including acute and chronic graft-versus-host disease, scleroderma, and cutaneous T-cell lymphoma. This process may offer a novel approach to viral control with minimal or no toxicity. We initiated an ex vivo and subsequently a clinical pilot trial utilizing Benzoporphyrin Derivative as the photosensitive compound. Ex vivo dosing studies identified the minimum energy levels of light exposure and concentrations of BPD that eradicated both cell-free and cell-associated HIV-1 infectivity without destroying the virus particles or infected leukocytes. Leukocytes so treated remained viable. They did demonstrate altered cytokine and chemokine expression with apoptosis induced in a minority of CD4 but not CD8 positive cells. Furthermore, there was a statistically significant increase in cytolytic T-cell activity expressed as percentage of granzyme-B release. A pilot in vivo, 24 week clinical trial in seven HIV-1 infected patients (all were required, upon entry, to have viral loads of > 10,000) using the photopheresis parameters established above demonstrated that the treatment was well tolerated and beneficial. Three individuals who had rapidly rising viral loads prior to initiating therapy stabilized once treatment began. Two of which had a (sustained) greater than .5 log decrement and 5 had stable plasma viral loads (less than a .5 log increment or decrement) with varied effects on absolute CD4 and CD8 positive lymphocytes counts. One subject achieved a greater than 1 log decrement in HIV-1 plasma viral load also developed undetectable in vivo cell-free and cell-associated HIV-1 infectivity while demonstrating an increased in vitro lymphocyte mitogen stimulation index. Subsequently, under amended and successor protocol 5 additional 12 month courses were administered to three additional patients and two of the previous enrollees. The area under the curve for viral load (viral load x # of weeks) for these twelve courses of therapy showed a significant decrease from pre to post therapy (p 0.007). There were no significant changes in CD4 or CD8 numbers area under the curve (CD4 number # of weeks and CD8 number x # of weeks). None of the subjects developed an AIDS defining illness during the course of therapy nor were there any treatment associated toxicities. These studies suggest that ECP augments activity of various arms of the immune system without any significant toxicity and may be effective in controlling HIV replication. We now plan a randomized Phase II study utilizing long-term photopheresis (twice monthly for 48 weeks) in addition to anti-retroviral therapy versus anti-retroviral therapy alone to further determine efficacy and mechanism of activity.

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