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1.
Phys Rev Lett ; 129(1): 013602, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35841581

ABSTRACT

Quantum non-Gaussian mechanical states are already required in a range of applications. The discrete building blocks of such states are the energy eigenstates-Fock states. Despite progress in their preparation, the remaining imperfections can still invisibly cause loss of the aspects critical for their applications. We derive and apply the most challenging hierarchy of quantum non-Gaussian criteria on the characterization of single trapped-ion oscillator mechanical Fock states with up to 10 phonons. We analyze the depth of these quantum non-Gaussian features under intrinsic mechanical heating and predict their requirement for reaching quantum advantage in the sensing of a mechanical force.

2.
S Afr Med J ; 110(8b): 13057, 2020 Aug 31.
Article in English | MEDLINE | ID: mdl-32880257

ABSTRACT

Heart failure with a reduced ejection fraction (HFrEF) is a condition frequently encountered by healthcare professionals and, in order to achieve the best outcomes for patients, needs to be managed optimally. This guideline document is based on the European Society of Cardiology Guidelines for the treatment of acute and chronic heart failure published in 2016, and summarises what is considered the best current management of patients with the condition. It provides information on the definition, diagnosis and epidemiology of HFrEF in the African context. The best evidence-based treatments for HFrEF are discussed, including established therapies (beta-blockers, ACE-i/ARBs, mineralocorticoid receptor antagonists (MRAs), diuretics) that form the cornerstone of heart failure management as well as therapies that have only recently entered clinical use (angiotensin receptor-neprilysin inhibitor (ARNI), sodium/glucose cotransporter-2 (SGLT2) inhibitors). Guidance is offered in terms of more invasive therapies (revascularisation, implantable cardioverter defibrillators (ICDs) and cardiac resynchronisation therapy (CRT) by implantation of a biventricular pacemaker with (CRT-D) or without (CRT-P) an ICD, left ventricular assist device (LVAD) use and heart transplantation) in order to ensure efficient use of these expensive treatment modalities in a resource-limited environment. Furthermore, additional therapies (digoxin, hydralazine and nitrates, ivabradine, iron supplementation) are discussed and advice is provided on general preventive strategies (vaccinations). Sections to discuss conditions that are particularly prevalent in sub-Saharan Africa (HIV-associated cardiomyopathy (CMO), peripartum CMO, rheumatic heart disease, atrial fibrillation) have been added to further improve clinical care for these commonly encountered disease processes. You are encouraged to read the complete 2016 ESC Heart Failure guideline: Ponikowski P, Voors AA, Anker SD, et al.; on behalf of the European Society of Cardiology. 2016 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur Heart J 2016,37:2129-2200.


Subject(s)
Cardiovascular Agents/therapeutic use , Heart Failure/therapy , Acute Disease , Cardiovascular Agents/pharmacology , Chronic Disease , Defibrillators, Implantable , Heart Failure/physiopathology , Heart Transplantation , Heart-Assist Devices , Humans , Pacemaker, Artificial , South Africa
3.
Phys Rev Lett ; 120(25): 253602, 2018 Jun 22.
Article in English | MEDLINE | ID: mdl-29979074

ABSTRACT

The vast majority of physical objects we are dealing with are almost exclusively made of atoms. Because of their discrete level structure, single atoms have proved to be emitters of light, which is incompatible with the classical description of electromagnetic waves. We demonstrate this incompatibility for atomic fluorescence when scaling up the size of the source ensemble, which consists of trapped atomic ions, by several orders of magnitude. The presented measurements of nonclassical statistics on light unconditionally emitted from ensembles containing up to more than a thousand ions promise further scalability to much larger emitter numbers. The methodology can be applied to a broad range of experimental platforms focusing on the bare nonclassical character of single isolated emitters.

4.
Int J Immunopathol Pharmacol ; 20(1): 75-89, 2007.
Article in English | MEDLINE | ID: mdl-17346430

ABSTRACT

The question of whether T cell responses to SEREX-defined tumor antigens are under regulation of naturally occurring CD4+CD25+ regulatory T cells (nTreg cells) has not been answered. To address this issue, we first identified an HLA-A2.1-restricted T cell antigen epitope of SEREX-identified tumor antigen CML66L, 66Pa. The HLA-A2.1/66Pa peptide complex in vitro stimulated the in vivo-primed T cells as shown by increased T cell proliferation, higher secretion of the T cell cytokine interferon-gamma (IFN-gamma), increased production of intracellular IFN-gamma in CD8+ T cells, and higher T cell-mediated cytotoxicities of CML66L+ human tumor cells. This suggests that CML66L elicits T cell immune responses. We also developed a novel internal reference epitope for identification of T cell epitopes by construction of chimeric CML66L containing myeloid antigen proteinase 3 epitope Pr1 as a control. Finally, we found that nTreg cells regulates T cell responses to 66Pa, and that depletion of nTreg cells via a pro-apoptotic protein Bax-dependent mechanism enhances polyclonal T cell responses to 66Pa. These findings provide new insights into the T cell participation in SEREX-defined anti-tumor immune responses and novel direction in enhancement of anti-leukemia immunotherapy by modulation of homeostasis of nTreg cells.


Subject(s)
Antigens, Neoplasm/genetics , CD4-Positive T-Lymphocytes/physiology , HLA-A2 Antigen/physiology , Interleukin-2 Receptor alpha Subunit/physiology , T-Lymphocytes, Regulatory/physiology , T-Lymphocytes/metabolism , Animals , Antigens/immunology , Antigens, Neoplasm/immunology , Apoptosis/physiology , Cell Line , Cloning, Molecular , Epitopes/genetics , Epitopes/immunology , HeLa Cells , Homeostasis/physiology , Humans , Immunoglobulin G/physiology , Interferon-gamma/physiology , Mice , Mice, Transgenic , Peptides/immunology , T-Lymphocytes, Cytotoxic/immunology , Transfection , Vaccines, DNA , bcl-2-Associated X Protein/physiology
5.
Gene Ther ; 14(4): 316-23, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17024104

ABSTRACT

Melanoma patients with metastases have a very low survival rate and limited treatment options. Therefore, the targeting of melanoma cells when they begin to invade and metastasize would be beneficial. An adhesion molecule that is upregulated at the vertical growth phase is the melanoma cell adhesion molecule (MCAM/MUC18). MUC18 is expressed in late primary and metastatic melanoma with little or no expression on normal melanocytes. We utilized the alphavirus-based DNA plasmid, SINCp, encoding murine MUC18 (SINCp c-muMUC18) for vaccination against B16F10 murine melanoma cells expressing murine MUC18. This vaccine effectively protected mice from lethal challenges with melanoma-expressing murine MUC18 in both primary and metastatic tumor models. Vaccination against MUC18 elicited effective humoral and CD8+ T-cell immune responses against melanoma. We propose that targeting molecules important in tumor invasion may be useful in the design of future strategies for the prevention and treatment of melanoma.


Subject(s)
Genetic Therapy/methods , Melanoma/therapy , Skin Neoplasms/therapy , Vaccines, DNA/administration & dosage , Alphavirus/genetics , Animals , CD146 Antigen/genetics , Cell Line, Tumor , DNA Fragmentation , Flow Cytometry , Immunotherapy/methods , Lymphocyte Activation , Melanoma/immunology , Melanoma/secondary , Mice , Mice, Inbred C57BL , Neoplasm Invasiveness/immunology , Neoplasms, Experimental , Skin Neoplasms/immunology , T-Lymphocytes, Cytotoxic/immunology
6.
Cancer Gene Ther ; 8(4): 259-68, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11393278

ABSTRACT

The gene for HER2/neu is overexpressed in 30-40% of breast and ovarian cancers, and this overexpression correlates with increased metastasis and poor prognosis. The HER2/neu gene product, a transmembrane protein kinase member of the EGF receptor family, has significant potential as a tumor antigen for vaccination. We inserted the sequence for neu into a novel plasmid called ELVIS containing a Sindbis virus replicon that reproduces multiple copies of mRNA. Mice vaccinated one time intramuscularly demonstrated a strong antibody response against A2L2, a murine breast cancer cell line transfected to express neu. Vaccinated mice challenged in the mammary fatpad with A2L2 had reduced tumor incidence and reduced tumor mass compared to mice challenged with tumor cells lacking the neu insert. Intradermal vaccination was also protective and required 80% less plasmid for a similar level of protection. Vaccination reduced the incidence of lung metastasis from mammary fatpad tumors and reduced the number of lung metastases resulting from intravenous injection of A2L2 cells. Cytotoxic T lymphocytes cultures of immune spleen cells with P815-neu cells produced high levels of interferon-gamma indicating an antigen-specific Th1-type immune response resulting from the vaccination. In a spontaneous breast tumor model using neu transgenic mice, vaccination with ELVIS-neu protected against development of spontaneous breast tumors. Our preclinical data indicate that therapeutic vaccination of patients with ELVIS-neu may reduce metastasis from HER2/neu-expressing breast and ovarian tumors.


Subject(s)
Lung Neoplasms/prevention & control , Mammary Neoplasms, Experimental/prevention & control , Receptor, ErbB-2/genetics , Vaccination , Vaccines, DNA/therapeutic use , Animals , Female , Flow Cytometry , Incidence , Interferon-gamma/metabolism , Interleukin-4/metabolism , Lung Neoplasms/metabolism , Lung Neoplasms/secondary , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/pathology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Precipitin Tests , Spleen/immunology , T-Lymphocytes, Cytotoxic/immunology , Transfection
7.
Comb Chem High Throughput Screen ; 3(4): 289-302, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10974142

ABSTRACT

Vaccination against Helicobacter pylori using DNA sequences encoding Urease A and B subunits was compared to immunization with urease antigen and MTP-PE in a liposome formulation. To determine the effectiveness of a vaccine against H. pylori in a mouse model it is essential to quantify the number of H. pylori remaining in the stomachs following challenge with an inoculum of live bacteria. Culture assays and enzymatic assays produce inconsistent results often unsuitable to conclude if vaccine candidates are protective. To overcome this problem, we developed two assays: 1) a competitive quantitative PCR using a colorimetric readout and 2) a non-competitive direct quantitative PCR using a highly sensitive bioluminescent readout. The competitive PCR requires coamplification of a segment of the urease C sequence and an internal control standard in a competitive manner using a single set of primers. PCR products were quantified colorimetrically by an enzyme-linked immunosorbent assay and compared with known quantities of the internal control standard added to the PCR reaction. The highly sensitive, bioluminescent assay measures the amplified DNA directly using a flash-type luminescent tag and a specific probe. The Sydney strain of H. pylori was used for the mouse infection model. Quantification of H. pylori by either the bioluminescent assay or the competitive PCR was reliable, specific and sensitive compared to quantitative growth assays which often gave false results. The bioluminescent assay was much more sensitive and less labor/time intensive than the competitive PCR. The bioluminescent assay was able to quantitate as few as 100 bacteria, while the competitive assay could not detect less than 10(3) bacteria per mouse stomach. Quantification of H. pylori by bioluminescent assay was superior to the competitive assay and may be used for research applications, such as the development of vaccines, pathogenesis of gastric disease and monitoring of antibiotic treatment.


Subject(s)
Biological Assay/methods , Helicobacter Infections/prevention & control , Helicobacter pylori , Luminescent Measurements , Vaccines, DNA , Animals , Liposomes/chemistry , Liposomes/pharmacology , Mice , Mice, Inbred C57BL , Phosphatidylethanolamines/chemistry , Polymerase Chain Reaction/methods , Reproducibility of Results , Sensitivity and Specificity , Urease/genetics
8.
Helicobacter ; 5(1): 13-21, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10672046

ABSTRACT

BACKGROUND: The density of Helicobacter pylori is thought to correlate with the degree of inflammation and thus indirectly with the outcome of the infection. Rapid quantitative assays of H. pylori in gastric or duodenal mucosa are lacking. The aim was to develop quantitative assays using the polymerase chain reaction to assess the quantity of H. pylori in the gastric mucosa. METHODS: Competitive PCR was based on coamplification of a segment of the ureC sequence and an internal control using a single set of primers. PCR products were quantified colorimetrically by an enzyme-linked immunosorbent assay and compared with known quantities of the internal control standard added to the PCR reaction. The highly sensitive, noncompetitive PCR assay does not use coamplification and measures the amplified DNA sequence using a flash-type luminescent tag and a specific probe. The mouse infected model using H. pylori strain SS-1 was used to develop the assays. RESULTS: Quantification of H. pylori using either the competitive or noncompetitive PCR was reliable, highly sensitive and specific. CONCLUSIONS: The ability to rapidly quantitate H. pylori from gastric mucosa should be useful to investigate the role of H. pylori density and infection outcome, as well as to monitor the effectiveness of antibiotic treatment or vaccines against H. pylori.


Subject(s)
Helicobacter Infections/microbiology , Helicobacter pylori/genetics , Polymerase Chain Reaction/methods , Stomach/microbiology , Animals , Cholera Toxin/administration & dosage , DNA, Bacterial/analysis , DNA, Bacterial/genetics , Gastric Mucosa/microbiology , Helicobacter Infections/prevention & control , Mice , Mice, Inbred C57BL , Reproducibility of Results , Specific Pathogen-Free Organisms , Urease/administration & dosage , Vaccination
9.
Am J Gastroenterol ; 95(1): 57-61, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10638559

ABSTRACT

OBJECTIVE: To investigate further the phenomenon of pharmacological tolerance to H2-receptor antagonists, we undertook a study of the antisecretory effect of ranitidine with continuous daily administration. METHODS: A total of 28 healthy male volunteers were given ranitidine 150 mg q.i.d. for 5 days. Twenty-four-hour intragastric pH monitoring was performed predosing and on days 1 and 5 of ranitidine administration. Serial blood samples were collected on days 1 and 5 of ranitidine administration for pharmacokinetics. RESULTS: Mean 24-h intragastric pH was 2.62 predosing, 4.22 on day 1 of ranitidine administration and 3.28 on day 5 (p = 0.001, ranitidine day 1 vs. day 5). Intragastric pH was >3, 4, and 5 for 69.9%, 54.3%, and 35.9%, respectively, on day 1 of ranitidine administration and was 45.8%, 30.1%, and 20.8% on day 5 (p<0.005 for each comparison). Subjects' Helicobacter pylori status did not affect the antisecretory effect of ranitidine. There was no alteration in ranitidine pharmacokinetics to account for its reduced antisecretory effect. CONCLUSION: This study has demonstrated a statistically significant reduction in the antisecretory effect of ranitidine within 5 days of continuous administration which is not explained by altered ranitidine pharmacokinetics. This is further evidence for the development of a form of pharmacological tolerance to an H2-receptor antagonist within a few days of continuous daily dosing.


Subject(s)
Anti-Ulcer Agents/pharmacology , Drug Tolerance , Gastric Acid/metabolism , Histamine H2 Antagonists/pharmacology , Ranitidine/pharmacology , Administration, Oral , Adult , Anti-Ulcer Agents/administration & dosage , Anti-Ulcer Agents/pharmacokinetics , Drug Administration Schedule , Gastric Acidity Determination , Histamine H2 Antagonists/administration & dosage , Histamine H2 Antagonists/pharmacokinetics , Humans , Male , Middle Aged , Monitoring, Ambulatory , Ranitidine/administration & dosage , Ranitidine/pharmacokinetics
10.
AIDS Res Hum Retroviruses ; 14(5): 409-17, 1998 Mar 20.
Article in English | MEDLINE | ID: mdl-9546800

ABSTRACT

Immunoliposomes containing monoclonal antibodies (MAbs) to the costimulatory molecules CD28 and CTLA4 and their counterreceptors B7-1 (CD80) and B7-2 (CD86) were evaluated for the ability to increase the immune response to recombinant envelope protein rgp120 of the MN strain of human immunodeficiency virus type 1 (HIV-1) during vaccination. MAbs were attached to rgp120-containing liposomes via a biotin-avidin-biotin bridge. Mice vaccinated with immunoliposomes were found to have a strong delayed-type hypersensitivity (DTH) response to the weakly immunogenic gp120 that was dependent on the presence of the MAbs. However, this vaccination protocol did not induce humoral immunity. The DTH response was not accompanied by increased production of interferon gamma (IFN-gamma) or interleukin 4 (IL-4), implying that the primary cellular interaction was between the immunoliposomes and cells of the reticuloendothelial system and not helper T (Th) cells. This strategy of incorporating antibodies to costimulatory molecules on the surface of antigen-containing particulates, such as liposomes or microspheres, can be used to increase DTH immune responses to protein or peptide vaccines.


Subject(s)
AIDS Vaccines/immunology , Antibodies, Monoclonal/immunology , HIV Antibodies/immunology , HIV Antigens/immunology , HIV Envelope Protein gp120/immunology , Liposomes/immunology , Vaccines, Synthetic/immunology , Adjuvants, Immunologic , Animals , B7-1 Antigen/immunology , CD28 Antigens/immunology , Humans , Hypersensitivity, Delayed/immunology , Immunoglobulin G/blood , Immunoglobulin G/isolation & purification , Interferon-gamma/immunology , Liposomes/metabolism , Mice , Mice, Inbred C3H , Middle Aged
11.
Helicobacter ; 2(2): 78-81, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9432332

ABSTRACT

BACKGROUND: A murine model for Helicobacter pylori infection could facilitate vaccine development. This study was designed to determine the effect of various conditions of dose, frequency of administration, and fasting on H. pylori infection of mice. MATERIALS AND METHODS: Balb/c and C3H/HeN mice were inoculated orogastrically with clinical isolates of H. pylori grown in liquid culture. At 2-week intervals, the stomachs were removed for secondary culture on horse blood agar and for histological analysis. H. pylori from secondary cultures or homogenized stomach tissue from infected mice was inoculated a second time in naïve animals. RESULTS: H. pylori was cultured with high frequency only from the stomachs of C3H/HeN mice. Fasting the mice and increasing the number of organisms inoculated did not increase the rate of infection. Histological analysis detected no inflammation, but mucus depletion and erosion were present in the stomachs of C3H/HeN mice. H. pylori organisms were not observed. Secondary cultures of H. pylori or homogenized infected stomach tissue did not cause infection when inoculated in naïve mice. CONCLUSIONS: Clinical isolates of H. pylori transiently infect C3H/HeN mice. This murine model is suitable for testing oral vaccines. Effective vaccination against H. pylori could prevent transient infection and reduce subsequent gastritis.


Subject(s)
Disease Models, Animal , Helicobacter Infections , Helicobacter pylori , Animals , Female , Mice , Mice, Inbred BALB C , Mice, Inbred C3H
12.
Eur Cytokine Netw ; 7(4): 693-8, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9010671

ABSTRACT

The ability of cytokines to regulate and augment an immune response makes them likely agents to be included in vaccines. The systemic use of cytokines as vaccine adjuvants has been hampered by toxicity at effective doses. More precise delivery of cytokines and immunogen can be achieved through the use of microparticle carriers such as liposomes. Several cytokines, including IL-2, IL-7, IL-6 and IFN-gamma have been shown to increase the adjuvant activity of liposomes. It may be possible to use certain cytokines to induce immunoglobulin production, others to induce cytotoxic T lymphocytes (CTL) and still others to promote IgA production at mucosal surfaces. An alternative to liposomes containing cytokines may be liposomes containing cytokine-inducing adjuvants such as MTPPE, MPL and QS21. This approach may produce undesirable immunomodulators as well as beneficial cytokines.


Subject(s)
Adjuvants, Immunologic/pharmacology , Cytokines/pharmacology , Vaccines, Synthetic/pharmacology , Animals , Antibody Formation/drug effects , Immunity, Cellular/drug effects , Liposomes , Mice
13.
AIDS Res Hum Retroviruses ; 11(8): 921-32, 1995 Aug.
Article in English | MEDLINE | ID: mdl-7492439

ABSTRACT

Dehydration-rehydration liposome vesicles (DRVs) containing various cytokines were evaluated for their ability to induce delayed-type hypersensitivity (DTH) and humoral immunity to the recombinant envelope protein rgp120 of the MN strain of human immunodeficiency virus type 1 (HIV-1). The DRVs trapped approximately 25% of the radiolabeled cytokines and approximately 17% of the radiolabeled rgp120 that were added. The level of trapping was greater than the aqueous volume of the DRVs, indicating association of the proteins with the lipid bilayer. Flow cytometric analysis using antibody to rgp120 or the V3 loop of rgp120 showed the diameter of the DRVs to be 2-7.5 microns. Transmission electron microscopy confirmed the heterogeneity in size of the DRVs and revealed morphological heterogeneity. Transmission electron microscopy with immunogold labeling also revealed the presence of rgp120 on the surface of the DRVs. In vitro bioassays demonstrated slow leakage of biologically active cytokines from DRVs soaked in tissue culture medium containing serum. Mice injected subcutaneously three times at 14-day intervals with DRVs containing 15 micrograms of rgp120 plus interleukin 6 (IL-6) or interferon gamma (IFN-gamma) produced significantly greater DTH responses than mice injected with DRVs containing rgp120 alone. Soluble rgp120 plus soluble IFN-gamma produced DTH in some experiments, but of lower magnitude than the comparable DRVs. Interleukin 6, but not IFN-gamma, increased the antibody titer to rgp120 when included in the DRVs. The mice did not develop antibodies to IFN-gamma or IL-6. Induction of DTH by vaccines may increase protection from viral pathogens such as HIV. Cytokine-containing liposomes may be an effective adjuvant for the induction of a DTH response to envelope-antigen subunit vaccines.


Subject(s)
Adjuvants, Pharmaceutic/administration & dosage , Cytokines/administration & dosage , HIV Envelope Protein gp120/administration & dosage , HIV Infections/immunology , HIV-1 , Hypersensitivity, Delayed/immunology , Animals , Drug Carriers , Female , HIV Infections/prevention & control , Humans , Hypersensitivity, Delayed/chemically induced , Liposomes , Mice , Mice, Inbred C3H , Vaccination
14.
Clin Exp Metastasis ; 13(4): 249-59, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7606887

ABSTRACT

Interleukin 1 alpha (IL1 alpha) and tumor necrosis factor alpha (TNF alpha) have been successfully incorporated into specific phosphatidylcholine (PC) and phosphatidylserine (PS) multilamellar vesicle (MLV) liposomes by modifying the concentration of calcium ion and pH of the encapsulation buffer. Under these conditions, some of the cytokines may attach to the exterior surface of the MLV and therefore be readily accessible to target cells for receptor binding and signal transduction. These cytokine-associated liposomes are stable for up to 2 weeks in serum-free buffer, and leakage of cytokines into medium containing 10% fetal bovine serum was about 50% at the end of a 3-day incubation period at 37 degrees C. The biological activities mediated by liposomal IL1 alpha and TNF alpha were specific: the stimulation of thymidine uptake in T-helper D10 lymphocytes and the cytolysis of TNF alpha-sensitive L929 target cells could be blocked by specific neutralizing antibodies in a dose-dependent fashion. When administered intravenously into C57BL/6 mice bearing the syngeneic B16F10 murine melanoma cells, dual entrapment of liposomal IL1 alpha and TNF alpha significantly reduced the number of metastatic tumor nodules in the lungs and prolonged the life span of the animals. Thus, liposomal IL1 alpha and TNF alpha displayed significant in vivo antitumor activity against the IL1 alpha- and TNF alpha-resistant B16F10 metastatic murine melanoma.


Subject(s)
Interleukin-1/administration & dosage , Lung Neoplasms/drug therapy , Lung Neoplasms/secondary , Melanoma, Experimental/drug therapy , Melanoma, Experimental/secondary , Tumor Necrosis Factor-alpha/administration & dosage , Animals , Calcium , Chemistry, Pharmaceutical , Drug Carriers , Female , Hydrogen-Ion Concentration , Interleukin-1/therapeutic use , Liposomes , Lung Neoplasms/immunology , Lymphocyte Activation/drug effects , Lymphocytes/drug effects , Lymphocytes/immunology , Melanoma, Experimental/immunology , Mice , Mice, Inbred C57BL , Neoplasm Transplantation , Phosphatidylcholines/chemical synthesis , Phosphatidylserines/chemical synthesis , Tumor Necrosis Factor-alpha/therapeutic use
16.
DNA Cell Biol ; 12(10): 881-92, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8274221

ABSTRACT

We report the isolation, sequence, and identification of a cDNA encoding the human kinesin light-chain (KLC) protein. The cDNA molecule consisted of 276 nucleotides of 5' untranslated region, the complete coding sequence of 1,710 nucleotides, and 322 nucleotides of 3' untranslated region. It encoded a polypeptide of 569 amino acids and a deduced molecular mass of 64,789 daltons. The predicted secondary internal structure of the KLC molecule consisted of about 27 contiguous repeats, each of approximately 21 amino acid residues, and could be divided into three domains. The amino-terminal domain consisted of heptad repeats typical of the rod domain of several cytoskeletal proteins. The central and carboxy-terminal domains consist of 21-mer repeats. KLC mRNA was expressed in most tissues analyzed. The gene, which was expressed in bacteria and Chinese hamster ovary cells, was provisionally assigned to the long arm of human chromosome 14.


Subject(s)
Kinesins/genetics , Microtubule-Associated Proteins/genetics , Amino Acid Sequence , Animals , Base Sequence , Blotting, Southern , Cells, Cultured , Chromosomes, Human, Pair 14 , Cloning, Molecular , DNA, Complementary , HeLa Cells , Humans , Microtubule-Associated Proteins/chemistry , Molecular Sequence Data , Precipitin Tests , Protein Structure, Secondary , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Sequence Homology, Amino Acid , T-Lymphocytes/metabolism
17.
J Natl Cancer Inst ; 84(13): 1008-16, 1992 Jul 01.
Article in English | MEDLINE | ID: mdl-1376778

ABSTRACT

BACKGROUND: Interleukin-1-alpha (IL-1) is a cytokine with potentially therapeutic immunoproliferative and tumoricidal activities. Preliminary clinical studies suggest that use of IL-1 may be restricted by dose-limiting hypotension. PURPOSE: The purpose of this study was to investigate the role of nitric oxide (NO.) as a possible mediator of this hypotension. METHODS: Cytokine-treated rat aortic smooth muscle cells were assayed for nitrite production, a stable breakdown product of nitric oxide. Nitric oxide synthase from smooth muscle cells was partially characterized in cytosol preparations using a novel Fe(2+)-myoglobin method to test for nitric oxide production. To determine the role of NO. on the immunorestorative and antineoplastic activity of IL-1, N omega-amino-L-arginine (NAA) or N omega-monomethyl-L-arginine (NMA), inhibitors of nitric oxide synthase, were added to either cultures of IL-1-dependent T cells or A375 melanoma cells exposed to IL-1. To investigate the effects of NAA in vivo, pentobarbital anesthetized dogs, which were made hypotensive by administration of IL-1, received a single intravenous bolus dose of NAA. The effects of NAA were then reversed by the administration of L-arginine. RESULTS: Our results show that cultured IL-1-activated rat aortic smooth muscle cells synthesize nitric oxide, a potent vasodilator. Induction of nitric oxide synthase is augmented by interferon-gamma and blocked by IL-1 receptor antagonist and by inhibitors of RNA or protein synthesis. Nitric oxide synthesis by IL-1-activated smooth muscle cells is inhibited by NAA, NMA, and N omega-nitro-L-arginine (NNA) with ED50 (i.e., effective dose for 50% inhibition) values of 20, 60, and 1000 microM, respectively; this rank order of inhibition is characteristic of an agonist-unregulated, inducible isoform of nitric oxide synthase. In smooth muscle cells, inhibition of NO. synthesis by NAA is reversed by excess L-arginine. Consistent with the induction of unregulated NO. synthesis in vascular smooth muscle in vivo, administration of IL-1 (50 micrograms/kg) to dogs caused a 33.5% decrease in systemic vascular resistance and a 28% decrease in blood pressure within 3 hours. Subsequent administration of NAA (20 mg/kg) rapidly and completely reversed the hypotension and increased systemic vascular resistance; these effects of NAA were reversed by L-arginine. Neither the immunoproliferative nor the tumoricidal activity of IL-1 was diminished by NAA. CONCLUSIONS: Our results indicate that (a) vascular smooth muscle is a likely source as well as a target of IL-1-induced NO. synthesis, causing vasodilatation and hypotension, (b) nitric oxide synthase inhibitors can fully reverse this hypotension, and (c) the therapeutically useful properties of IL-1 are not diminished by nitric oxide synthase inhibitors. IMPLICATIONS: Administration of inhibitors of nitric oxide synthase can reverse the pathological cardiovascular effects of IL-1 at concentrations that do not interfere with the potentially useful immunoproliferative or tumoricidal effects of this cytokine. In the context of the current clinical trials of IL-1, this finding would represent a very significant advantage.


Subject(s)
Amino Acid Oxidoreductases/drug effects , Arginine/analogs & derivatives , Hypotension/drug therapy , Interleukin-1/antagonists & inhibitors , Muscle, Smooth, Vascular/enzymology , Amino Acid Oxidoreductases/antagonists & inhibitors , Amino Acid Oxidoreductases/biosynthesis , Animals , Arginine/pharmacology , Arginine/therapeutic use , Cell Division/drug effects , Dogs , Enzyme Induction/drug effects , Humans , Hypotension/chemically induced , Interleukin-1/adverse effects , Mice , Muscle, Smooth, Vascular/drug effects , Nitric Oxide Synthase , Rats , Rats, Inbred F344 , Tumor Cells, Cultured/cytology , Tumor Cells, Cultured/drug effects , Vascular Resistance/drug effects
18.
Cytokine ; 4(2): 106-13, 1992 Mar.
Article in English | MEDLINE | ID: mdl-1378763

ABSTRACT

Lipopolysaccharide (LPS) either in its soluble form or associated with multilamellar phospholipid vesicles (liposomes) was investigated for its ability to induce human monocyte interleukin (IL)-1 alpha and IL-1 beta. When human monocytes were activated in vitro by LPS either in its soluble form or presented at the surface of lyophilized multilamellar vesicles (Lyo-MLV-LPS), both IL-1 alpha and IL-1 beta were detected intracellularly and extracellularly, using specific antisera. In correlation with these findings, the mRNAs for IL-1 alpha and IL-1 beta were both found by Northern blot analysis. However, when human monocytes were stimulated by LPS incorporated into multilamellar vesicles which had not been previously lyophilized, a different pattern of IL-1 protein and message was observed. IL-1 alpha activity was detected only intracellularly and not in the supernatant, while IL-1 beta was not produced at all. Northern blotting revealed only mRNA for IL-1 alpha as soon as 0.5 h after stimulation and none for IL-1 beta. These data indicate independent induction of IL-1 alpha and IL-1 beta. Moreover, it appears that the regulation occurs at the transcriptional level, since with MLV-LPS only the mRNA for IL-1 alpha was induced. The lack of IL-1 beta could be due to either a blockage at the DNA level, an undetectable level of IL-1 beta mRNA, or a very short halflife for IL-1 beta mRNA. These findings indicate that although IL-1 alpha and IL-1 beta may have identical biological properties and share the same receptor, their induction and secretion are regulated by independent pathways.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Interleukin-1/biosynthesis , Lipopolysaccharides/toxicity , Monocytes/metabolism , Animals , Blotting, Northern , Cell Line , Cell Membrane/physiology , Cytosol/physiology , DNA/isolation & purification , Humans , Interleukin-1/metabolism , Mice , Monocytes/drug effects , Nucleic Acid Hybridization , RNA/isolation & purification
19.
J Immunol ; 148(1): 84-91, 1992 Jan 01.
Article in English | MEDLINE | ID: mdl-1727877

ABSTRACT

In an attempt to define the mechanism by which endotoxin induces its biologic activity, LPS was incorporated into phospholipid vesicles (liposomes) and compared with free LPS for ability to stimulate human monocytes. Activation of human monocytes by free LPS caused the translocation of protein kinase C (PKC) from the cytosol to the plasma membranes, the production of both IL-1, alpha and beta, and IL-1 secretion. Activation by LPS presented in multilamellar vesicles (MLV)-LPS caused IL-1 production but not IL-1 secretion. Moreover, MLV-LPS did not induce PKC translocation. MLV themselves did not inhibit monocyte stimulation by LPS, since LPS presented at the surface of lyophilized liposomes behaved like free LPS in cell activation. In contrast, MLV-LPS primed monocytes for subsequent LPS stimulation. When monocytes were activated by LPS in the presence of PKC inhibitors, no plasma membrane-associated PKC or IL-1 secretion was detected, whereas IL-1 production was observed. PKC inhibitors did not affect IL-1 alpha and IL-1 beta production, showing that PKC is not involved in the production of either IL-1. It can be concluded that IL-1 production and secretion are induced independently, and that IL-1 secretion involves PKC.


Subject(s)
Interleukin-1/metabolism , Monocytes/metabolism , Protein Kinase C/physiology , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine , Alkaloids/pharmacology , Biological Transport , Cell Compartmentation , Cell Membrane/enzymology , Dose-Response Relationship, Drug , Humans , In Vitro Techniques , Isoenzymes/physiology , Isoquinolines/pharmacology , Lipopolysaccharides/administration & dosage , Liposomes , Piperazines/pharmacology , Protein Kinase C/antagonists & inhibitors , Staurosporine
20.
J Immunol ; 147(7): 2164-9, 1991 Oct 01.
Article in English | MEDLINE | ID: mdl-1918951

ABSTRACT

To determine whether membrane-associated IL-1 is palmitylated, we labeled LPS-activated human monocytes with [3H]palmitic acid. The plasma membranes were isolated, and the membrane proteins extracted and analyzed simultaneously by SDS-PAGE-autoradiography and Western blot analysis from the same gel. When the monocytes were labeled with [3H]palmitate, 23- and 31-kDa bands were visualized, for membrane-associated IL-1 and its precursor, respectively. The 31- and 23-kDa bands were excised from several gels and rehydrated and analyzed again by SDS-PAGE, autoradiography, and Western blot analysis. The 23- and 31-kDa bands appeared again by both methods. To further investigate membrane-associated IL-1 acylation, human monocytes were labeled with [3H]palmitate, the plasma membranes isolated, and the membrane proteins extracted by CHAPS detergent. Immunoprecipitation of isolated membrane proteins using anti-IL-1 antibodies revealed two bands of 23 and 31 kDa after autoradiography. The studies demonstrate that both membrane-associated IL-1 and the IL-1 precursor are acylated with palmitic acid.


Subject(s)
Interleukin-2/metabolism , Palmitic Acids/metabolism , Acylation , Autoradiography , Blotting, Western , Cells, Cultured , Glycosylation , Humans , Membrane Proteins/immunology , Palmitic Acid , Precipitin Tests
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