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1.
Biophys J ; 122(22): 4425-4439, 2023 11 21.
Article in English | MEDLINE | ID: mdl-37992690

ABSTRACT

Mechanisms by which electric (E) or magnetic (B) fields might be harnessed to affect tumor cell behavior remain poorly defined, presenting a barrier to translation. We hypothesized in early studies that the glycocalyx of lung cancer cells might play a role in mediating plasma membrane leak by low-frequency pulsed magnetic fields (Lf-PMF) generated on a low-energy solenoid platform. In testing glioblastoma and neuroblastoma cells known to overexpress glycoproteins rich in modifications by the anionic glycan sialic acid (Sia), exposure of brain tumor cells on the same platform to a pulse train that included a 5 min 50Hz Lf-PMF (dB/dt ∼ 2 T/s at 10 ms pulse widths) induced a very modest but significant protease leak above that of control nonexposed cells (with modest but significant reductions in long-term tumor cell viability after the 5 min exposure). Using a markedly higher dB/dt system (80 T/s pulses, 70 µs pulse-width at 5.9 cm from a MagVenture coil source) induced markedly greater leak by the same cells, and eliminating Sia by treating cells with AUS sialidase immediately preexposure abrogated the effect entirely in SH-SY5Y neuroblastoma cells, and partially in T98G glioblastoma cells. The system demonstrated significant leak (including inward leak of propidium iodide), with reduced leak at lower dB/dt in a variety of tumor cells. The ability to abrogate Lf-PMF protease leak by pretreatment with sialidase in SH-SY5Y brain tumor cells or with heparin lyase in A549 lung tumor cells indicated the importance of heavy Sia or heparan sulfate glycosaminoglycan glycocalyx modifications as dominant glycan species mediating Lf-PMF membrane leak in respective tumor cells. This "first-physical" Lf-PMF tumor glycocalyx event, with downstream cell stress, may represent a critical and "tunable" transduction mechanism that depends on characteristic anionic glycans overexpressed by distinct malignant tumors.


Subject(s)
Brain Neoplasms , Glioblastoma , Neuroblastoma , Humans , Glycocalyx/metabolism , Neuraminidase , Neuroblastoma/metabolism , Neuroblastoma/pathology , Magnetic Fields , Cell Line, Tumor , N-Acetylneuraminic Acid/metabolism , Peptide Hydrolases , Polysaccharides
2.
Biophys J ; 118(7): 1552-1563, 2020 04 07.
Article in English | MEDLINE | ID: mdl-32142642

ABSTRACT

Tumor cells express a unique cell surface glycocalyx with upregulation of sulfated glycosaminoglycans and charged glycoproteins. Little is known about how electromagnetic fields interact with this layer, particularly with regard to harnessing unique properties for therapeutic benefit. We applied a pulsed 20-millitesla (mT) magnetic field with rate of rise (dB/dt) in the msec range to cultured tumor cells to assess whether this affects membrane integrity as measured using cytolytic assays. A 10-min exposure of A549 human lung cancer cells to sequential 50- and 385-Hz oscillating magnetic fields was sufficient to induce intracellular protease release, suggesting altered membrane integrity after the field exposure. Heparinase treatment, which digests anionic sulfated glycan polymers, before exposure rendered cells insensitive to this effect. We further examined a non-neoplastic human primary cell line (lung lymphatic endothelial cells) as a typical normal host cell from the lung cancer microenvironment and found no effect of field exposure on membrane integrity. The field exposure was also sufficient to alter proliferation of tumor cells in culture, but not that of normal lymphatic cells. Pulsed magnetic field exposure of human breast cancer cells that express a sialic-acid rich glycocalyx also induced protease release, and this was partially abrogated by sialidase pretreatment, which removes cell surface anionic sialic acid. Scanning electron microscopy showed that field exposure may induce unique membrane "rippling" along with nanoscale pores on A549 cells. These effects were caused by a short exposure to pulsed 20-mT magnetic fields, and future work may examine greater magnitude effects. The proof of concept herein points to a mechanistic basis for possible applications of pulsed magnetic fields in novel anticancer strategies.


Subject(s)
Endothelial Cells , Magnetic Fields , Cell Survival , Electromagnetic Fields , Humans , Tumor Cells, Cultured
3.
Clin Infect Dis ; 70(9): 2002-2004, 2020 04 15.
Article in English | MEDLINE | ID: mdl-31504321

ABSTRACT

Encephalopathy complicates beta-lactam therapy, particularly with impaired renal function, though no studies have reported ceftaroline-associated encephalopathy. Among 28 patients with estimated glomerular filtration rates <30 mL/min who received ≥5 days of ceftaroline, 3 developed encephalopathy. Ceftaroline, when dosed supra-therapeutically for serious infections, may be a cause of antibiotic-associated encephalopathy.


Subject(s)
Brain Diseases , Renal Insufficiency , Anti-Bacterial Agents/adverse effects , Brain Diseases/chemically induced , Brain Diseases/drug therapy , Cephalosporins/adverse effects , Humans , Renal Insufficiency/chemically induced , Renal Insufficiency/complications , Ceftaroline
4.
Circ Res ; 119(2): 210-21, 2016 07 08.
Article in English | MEDLINE | ID: mdl-27225479

ABSTRACT

RATIONALE: Lymphatic vessel growth is mediated by major prolymphangiogenic factors, such as vascular endothelial growth factor (VEGF-C) and VEGF-D, among other endothelial effectors. Heparan sulfate is a linear polysaccharide expressed on proteoglycan core proteins on cell membranes and matrix, playing roles in angiogenesis, although little is known about any function(s) in lymphatic remodeling in vivo. OBJECTIVE: To explore the genetic basis and mechanisms, whereby heparan sulfate proteoglycans mediate pathological lymphatic remodeling. METHODS AND RESULTS: Lymphatic endothelial deficiency in the major heparan sulfate biosynthetic enzyme N-deacetylase/N-sulfotransferase-1 (Ndst1; involved in glycan-chain sulfation) was associated with reduced lymphangiogenesis in pathological models, including spontaneous neoplasia. Mouse mutants demonstrated tumor-associated lymphatic vessels with apoptotic nuclei. Mutant lymphatic endothelia demonstrated impaired mitogen (Erk) and survival (Akt) pathway signaling and reduced VEGF-C-mediated protection from starvation-induced apoptosis. Lymphatic endothelial-specific Ndst1 deficiency (in Ndst1(f/f)Prox1(+/CreERT2) mice) was sufficient to inhibit VEGF-C-dependent lymphangiogenesis. Lymphatic heparan sulfate deficiency reduced phosphorylation of the major lymphatic growth receptor VEGF receptor-3 in response to multiple VEGF-C species. Syndecan-4 was the dominantly expressed heparan sulfate proteoglycan in mouse lymphatic endothelia, and pathological lymphangiogenesis was impaired in Sdc4((-/-)) mice. On the lymphatic cell surface, VEGF-C induced robust association between syndecan-4 and VEGF receptor-3, which was sensitive to glycan disruption. Moreover, VEGF receptor-3 mitogen and survival signaling was reduced in the setting of Ndst1 or Sdc4 deficiency. CONCLUSIONS: These findings demonstrate the genetic importance of heparan sulfate and the major lymphatic proteoglycan syndecan-4 in pathological lymphatic remodeling. This may introduce novel future strategies to alter pathological lymphatic-vascular remodeling.


Subject(s)
Lymphangiogenesis/physiology , Lymphatic Vessels/pathology , Lymphatic Vessels/physiology , Proteoglycans/physiology , Vascular Endothelial Growth Factor C/physiology , Vascular Endothelial Growth Factor Receptor-3/physiology , Animals , Cells, Cultured , Humans , Lung/cytology , Lung/metabolism , Mice
5.
J Biol Chem ; 291(24): 12627-12640, 2016 Jun 10.
Article in English | MEDLINE | ID: mdl-27044744

ABSTRACT

TNF-stimulated gene-6 (TSG-6) is a multifunctional protein secreted in response to pro-inflammatory stimuli by a wide range of cells, including neutrophils, monocytes, and endothelial cells. It has been shown to mediate anti-inflammatory and protective effects when administered in disease models, in part, by reducing neutrophil infiltration. Human TSG-6 inhibits neutrophil migration by binding CXCL8 through its Link module (Link_TSG6) and interfering with the presentation of CXCL8 on cell-surface glycosaminoglycans (GAGs), an interaction that is vital for the function of many chemokines. TSG-6 was also found to interact with chemokines CXCL11 and CCL5, suggesting the possibility that it may function as a broad specificity chemokine-binding protein, functionally similar to those encoded by viruses. This study was therefore undertaken to explore the ability of TSG-6 to regulate the function of other chemokines. Herein, we demonstrate that Link_TSG6 binds chemokines from both the CXC and CC families, including CXCL4, CXCL12, CCL2, CCL5, CCL7, CCL19, CCL21, and CCL27. We also show that the Link_TSG6-binding sites on chemokines overlap with chemokine GAG-binding sites, and that the affinities of Link_TSG6 for these chemokines (KD values 1-85 nm) broadly correlate with chemokine-GAG affinities. Link_TSG6 also inhibits chemokine presentation on endothelial cells not only through a direct interaction with chemokines but also by binding and therefore masking the availability of GAGs. Along with previous work, these findings suggest that TSG-6 functions as a pluripotent regulator of chemokines by modulating chemokine/GAG interactions, which may be a major mechanism by which TSG-6 produces its anti-inflammatory effects in vivo.


Subject(s)
Cell Adhesion Molecules/metabolism , Chemokines/metabolism , Endothelial Cells/metabolism , Glycosaminoglycans/metabolism , Animals , Binding Sites , Cell Adhesion , Cell Adhesion Molecules/genetics , Cell Line , Cell Movement , Cells, Cultured , Endothelial Cells/cytology , Heparin/metabolism , Humans , Models, Molecular , Mutation , Protein Binding , Surface Plasmon Resonance
6.
Curr Top Microbiol Immunol ; 389: 1-29, 2015.
Article in English | MEDLINE | ID: mdl-25821102

ABSTRACT

HIV Attachment. In this cross section, HIV is shown at the top and a target cell is shown at the bottom in blues. HIV envelope protein (A) has bound to the receptor CD4 (B) and then to coreceptor CCR5 (C), causing a change in conformation that inserts fusion peptides into the cellular membrane Antiretroviral therapy changed the face of HIV/AIDS from that of soon and certain death to that of a chronic disease in the years following introduction of highly active antiretroviral therapy in 1995-1996 (initially termed HAART, but now most often abbreviated to ART since not all combinations of regimens are equally active). Since then, many new agents have been developed and introduced in response to problems of resistance, toxicity, and tolerability, and great advances have been achieved in accessibility of HIV drugs in resource-poor global regions. Potential challenges that providers of HIV therapy will face in the coming decade include continuing problems with resistance, especially where access to drugs is inconsistent, determining how best to combine new and existing agents, defining the role of preventive treatment (pre-exposure prophylaxis or PrEP), and evaluating the potential of strategies for cure in some populations.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Humans
7.
J Immunol ; 192(5): 2133-42, 2014 Mar 01.
Article in English | MEDLINE | ID: mdl-24493818

ABSTRACT

Dendritic cells (DCs) are potent APCs essential for initiating adaptive immunity. Following pathogen exposure, trafficking of DCs to lymph nodes (LNs) through afferent lymphatic vessels constitutes a crucial step in the execution of their functions. The mechanisms regulating this process are poorly understood, although the involvement of certain chemokines in this process has recently been reported. In this study, we demonstrate that genetically altering the fine structure (N-sulfation) of heparan sulfate (HS) specifically in mouse lymphatic endothelium significantly reduces DC trafficking to regional LNs in vivo. Moreover, this alteration had the unique functional consequence of reducing CD8(+) T cell proliferative responses in draining LNs in an ovalbumin immunization model. Mechanistic studies suggested that lymphatic endothelial HS regulates multiple steps during DC trafficking, including optimal presentation of chemokines on the surface of DCs, thus acting as a co-receptor that may function "in trans" to mediate chemokine receptor binding. This study not only identifies novel glycan-mediated mechanisms that regulate lymphatic DC trafficking, but it also validates the fine structure of lymphatic vascular-specific HS as a novel molecular target for strategies aiming to modulate DC behavior and/or alter pathologic T cell responses in lymph nodes.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Cell Movement/immunology , Dendritic Cells/immunology , Endothelium, Lymphatic/immunology , Heparitin Sulfate/immunology , Lymph Nodes/immunology , Animals , CD8-Positive T-Lymphocytes/cytology , Cell Movement/genetics , Chemokines/genetics , Chemokines/immunology , Dendritic Cells/cytology , Endothelium, Lymphatic/cytology , Heparitin Sulfate/genetics , Humans , Lymph Nodes/cytology , Mice , Mice, Transgenic
8.
J Infect Chemother ; 19(1): 42-9, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22797874

ABSTRACT

There are many limitations to the current antibiotics used for the treatment of severe methicillin-resistant Staphylococcus aureus (MRSA) infections. Ceftaroline is a new fifth-generation cephalosporin approved for the treatment of skin and soft tissue infections caused by MRSA and community-acquired pneumonia. We propose that ceftaroline can also be used successfully in more severe MRSA infections, including endocarditis. We conducted a retrospective chart review in a university-affiliated Department of Veterans Affairs hospital in San Diego, California (USA) of ten inpatients treated with ceftaroline for severe MRSA infection, including five cases of probable endocarditis (including two endocardial pacemaker infections), one case of pyomyositis with possible endocarditis, two cases of pneumonia (including one case of empyema), two cases of septic arthritis (including one case of prosthetic joint infection), and two cases of osteomyelitis. Seven of the 10 patients achieved microbiological cure. Six of the 10 patients achieved clinical cure. Seven patients were discharged from the hospital. Three patients were placed on comfort care and expired in the hospital; one achieved microbiological cure before death, and two remained bacteremic at time of death. In most patients, ceftaroline was effective for treatment of MRSA bacteremia and other severe MRSA infections. Adverse effects seen included rash, eosinophilia, pruritus, and Clostridium difficile infection. Ceftaroline can be a safe and effective drug for treatment of severe MRSA infections, and further comparative studies are warranted.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Bacteremia/drug therapy , Cephalosporins/therapeutic use , Endocarditis, Bacterial/drug therapy , Methicillin-Resistant Staphylococcus aureus/drug effects , Prodrugs/therapeutic use , Staphylococcal Infections/drug therapy , Adult , Aged , Aged, 80 and over , Arthritis, Infectious/drug therapy , Arthritis, Infectious/microbiology , Bacteremia/microbiology , Endocarditis, Bacterial/microbiology , Female , Humans , Male , Middle Aged , Osteomyelitis/drug therapy , Osteomyelitis/microbiology , Pneumonia, Staphylococcal/drug therapy , Pneumonia, Staphylococcal/microbiology , Retrospective Studies , Staphylococcal Infections/microbiology , Treatment Outcome , Ceftaroline
9.
J Biol Chem ; 286(17): 14952-62, 2011 Apr 29.
Article in English | MEDLINE | ID: mdl-21343305

ABSTRACT

Growth and remodeling of lymphatic vasculature occur during development and during various pathologic states. A major stimulus for this process is the unique lymphatic vascular endothelial growth factor-C (VEGF-C). Other endothelial growth factors, such as fibroblast growth factor-2 (FGF-2) or VEGF-A, may also contribute. Heparan sulfate is a linear sulfated polysaccharide that facilitates binding and action of some vascular growth factors such as FGF-2 and VEGF-A. However, a direct role for heparan sulfate in lymphatic endothelial growth and sprouting responses, including those mediated by VEGF-C, remains to be examined. We demonstrate that VEGF-C binds to heparan sulfate purified from primary lymphatic endothelia, and activation of lymphatic endothelial Erk1/2 in response to VEGF-C is reduced by interference with heparin or pretreatment of cells with heparinase, which destroys heparan sulfate. Such treatment also inhibited phosphorylation of the major VEGF-C receptor VEGFR-3 upon VEGF-C stimulation. Silencing lymphatic heparan sulfate chain biosynthesis inhibited VEGF-C-mediated Erk1/2 activation and abrogated VEGFR-3 receptor-dependent binding of VEGF-C to the lymphatic endothelial surface. These findings prompted targeting of lymphatic N-deacetylase/N-sulfotransferase-1 (Ndst1), a major sulfate-modifying heparan sulfate biosynthetic enzyme. VEGF-C-mediated Erk1/2 phosphorylation was inhibited in Ndst1-silenced lymphatic endothelia, and scratch-assay responses to VEGF-C and FGF-2 were reduced in Ndst1-deficient cells. In addition, lymphatic Ndst1 deficiency abrogated cell-based growth and proliferation responses to VEGF-C. In other studies, lymphatic endothelia cultured ex vivo from Ndst1 gene-targeted mice demonstrated reduced VEGF-C- and FGF-2-mediated sprouting in collagen matrix. Lymphatic heparan sulfate may represent a novel molecular target for therapeutic intervention.


Subject(s)
Lymphangiogenesis , Vascular Endothelial Growth Factor C/physiology , Animals , Endothelium, Lymphatic , Heparitin Sulfate/deficiency , Lymphatic Vessels , Mice , Mitogen-Activated Protein Kinase 3/metabolism , Protein Binding , Sulfotransferases/metabolism , Vascular Endothelial Growth Factor Receptor-3
10.
Sci Rep ; 12(1): 5382, 2022 03 30.
Article in English | MEDLINE | ID: mdl-35354833

ABSTRACT

Survival from influenza A virus (IAV) infection largely depends on an intricate balance between pathogen clearance and immunomodulation in the lung. We demonstrate that genetic alteration of the glycan heparan sulfate (HS) in CD11c + cells via Ndst1f/f CD11cCre + mutation, which inhibits HS sulfation in a major antigen presenting cell population, reduces lung inflammation by A/Puerto Rico/8/1934(H1N1) influenza in mice. Mutation was also characterized by a reduction in lung infiltration by CD4+ regulatory T (Treg) cells in the late infection/effector phase, 9 days post inoculation (p.i.), without significant differences in lung CD8 + T cells, or Treg cells at an earlier point (day 5) following infection. Induction of under-sulfated HS via Ndst1 silencing in a model dendritic cell line (DC2.4) resulted in up-regulated basal expression of the antiviral cytokine interferon ß (IFN-ß) relative to control. Stimulating cells with the TLR9 ligand CpG resulted in greater nuclear factor-κB (NFκB) phosphorylation in Ndst1 silenced DC2.4 cells. While stimulating cells with CpG also modestly increased IFN-ß expression, this did not lead to significant increases in IFN-ß protein production. In further IFN-ß protein response studies using primary bone marrow DCs from Ndst1f/f CD11cCre + mutant and Cre- control mice, while trace IFN-ß protein was detected in response to CpG, stimulation with the TLR7 ligand R848 resulted in robust IFN-ß production, with significantly higher levels associated with DC Ndst1 mutation. In vivo, improved pathogen clearance in Ndst1f/f CD11cCre + mutant mice was suggested by reduced IAV AA5H nucleoprotein in lung examined in the late/effector phase. Earlier in the course of infection (day 5 p.i.), mean viral load, as measured by viral RNA, was not significantly different among genotypes. These findings point to novel regulatory roles for DC HS in innate and adaptive immunity during viral infection. This may have therapeutic potential and guide DC targeted HS engineering platforms in the setting of IAV or other respiratory viruses.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza A virus , Influenza, Human , Animals , Heparitin Sulfate , Humans , Inflammation/genetics , Mice , Mutation
11.
Physiol Rep ; 10(3): e15185, 2022 02.
Article in English | MEDLINE | ID: mdl-35150208

ABSTRACT

Pulmonary arterial hypertension (PAH) is associated with significant morbidity and mortality. PAH is characterized by pulmonary artery remodeling, elevated right ventricular pressure (RVP) and, ultimately, cardiac failure. Pulmonary endothelial cells can sense danger or damage caused by mechanical injury or pathogens through alarmin cytokines. These cytokines can signal proliferation to restore barrier integrity or aberrant hyperproliferation and remodeling. We hypothesized that IL-33 signals pulmonary artery endothelial cells to proliferate under hypertensive conditions during the remodeling response and rise in RVP. To test this hypothesis, pulmonary hypertension (PH) was induced in C57Bl/6J, IL-33 receptor gene deleted (ST2-/- ) and MYD88 gene deleted (MYD88-/- ) mice by exposure to 10% O2 and SU5416 injections (SUHX). RVP, arterial wall thickness, endothelial cell proliferation and IL-33 levels and signaling were evaluated. In response to SUHX. RVP increased in C57Bl/6J mice in response to SUHX (49% male and 70% female; p < 0.0001) and this SUHX response was attenuated in ST2-/- mice (29% male p = 0.003; 30% female p = 0.001) and absent in MYD88-/- mice. Wall thickness was increased in SUHX C57Bl/6J mice (p = 0.005), but not in ST2-/- or MYD88-/- mice. Proliferating cells were detected in C57Bl/6J mice by flow cytometry (CD31+ /BrDU+ ; p = 0.02) and immunofluorescence methods (Ki-67+). IL-33 was increased by SUHX (p = 0.03) but a genotype effect was not observed (p = 0.76). We observed that in hPAECs, IL-33 expression is regulated by both IL-33 and DLL4. These data suggest IL-33/ST2 signaling is essential for the endothelial cell proliferative response in PH.


Subject(s)
Hypertension, Pulmonary/metabolism , Interleukin-1 Receptor-Like 1 Protein/genetics , Interleukin-33/metabolism , Signal Transduction , Animals , Cells, Cultured , Female , Gene Deletion , Hypertension, Pulmonary/etiology , Indoles/toxicity , Interleukin-1 Receptor-Like 1 Protein/metabolism , Male , Mice , Mice, Inbred C57BL , Myeloid Differentiation Factor 88/genetics , Pyrroles/toxicity
12.
Open Forum Infect Dis ; 9(3): ofab606, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35146040

ABSTRACT

BACKGROUND: Observational data suggest ceftaroline may be effective for methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection (BSI), but comparative data with standard of care are limited. This analysis compares the outcomes of MRSA BSI treated with ceftaroline or daptomycin. METHODS: Multicenter, retrospective, observational cohort study of adult patients with MRSA BSI from 2010 to 2017. Patients treated with ≥72 hours of ceftaroline or daptomycin were included. Those clearing BSI before study drug and those with a pneumonia source were excluded. The primary outcome was composite treatment failure, defined as 30-day mortality, BSI duration ≥7 days on study drug, and 60-day MRSA BSI recurrence. Inverse probability of treatment weighted risk difference in composite failure between daptomycin and ceftaroline groups was computed and 15% noninferiority margin applied. RESULTS: Two hundred seventy patients were included; 83 ceftaroline and 187 daptomycin. Ceftaroline was noninferior to daptomycin with respect to composite failure (39% daptomycin, 32.5% ceftaroline; weighted risk difference, 7.0% [95% confidence interval, -5.0% to 19.0%]). No differences between treatment groups was observed for 30-day mortality or other secondary efficacy outcomes. Creatine phosphokinase elevation was significantly more common among daptomycin patients (5.3% vs 0%, P = .034). Rash was significantly more common among ceftaroline patients (10.8 vs 1.1%, P = .001). CONCLUSIONS: No difference in treatment failure or mortality was observed between MRSA BSI treated with ceftaroline or daptomycin. These data support future study of ceftaroline as a primary MRSA BSI treatment and current use of ceftaroline when an alternative to vancomycin and daptomycin is required.

13.
Neoplasia ; 23(11): 1137-1143, 2021 11.
Article in English | MEDLINE | ID: mdl-34715561

ABSTRACT

Early lung carcinoma development may be modulated by innate host cellular mechanisms that promote tumor growth and invasion. We recently identified how a loss-of-function mutation in the glycan sulfating enzyme N-deacetylase/N-sulfotransferase-1 (Ndst1; involved in heparan sulfate biosynthesis) targeted to antigen presenting cells (APCs) may augment acquired anti-tumor T cell immune mechanisms. Crossing this mutation (Ndst1f/f CD11cCre+) onto a model of inducible spontaneous Kras mutant lung cancer [CCSP-rtTA; (tetO7) CMV-Kras-G12D] allowed us to examine how the APC mutation affects the formation and growth of early lung carcinoma. We examined early bronchocentric adenoma formation in the model, and the frequency of such events was significantly reduced on the mutant background. This was associated with significant reductions in tumor associated FOXP3+ cellular infiltration and CD163+ M2-type macrophage infiltration. The findings evolved prior to effector CD8+ T cell infiltration into tumors. The impact of this unique glycan under-sulfating mutation on inhibiting early Kras G12D mutant bronchocentric adenoma formation along with a cellular phenotype of inhibited tumor infiltration by cells involved in suppressive T-regulatory cell signaling (FOXP3+ cells) or tumor-permissive M2 macrophage functions (CD163+ cells) provides insight on how glycan targeting may modulate innate cellular mechanisms during early lung tumor development. The findings may also impact the future design of host-centered immunologic anti-tumor therapeutic strategies.


Subject(s)
Adenoma/pathology , CD11c Antigen/metabolism , Lung Neoplasms/pathology , Mutation , Myeloid Cells/immunology , Polysaccharides/chemistry , Proto-Oncogene Proteins p21(ras)/genetics , Adenoma/etiology , Adenoma/metabolism , Animals , CD8-Positive T-Lymphocytes , Heparitin Sulfate/chemistry , Humans , Lung Neoplasms/etiology , Lung Neoplasms/metabolism , Lymphocytes, Tumor-Infiltrating/immunology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Myeloid Cells/metabolism , Myeloid Cells/pathology , Sulfates/metabolism , Sulfotransferases/physiology , T-Lymphocytes, Regulatory/immunology
14.
Infect Control Hosp Epidemiol ; 42(1): 51-56, 2021 01.
Article in English | MEDLINE | ID: mdl-32943129

ABSTRACT

OBJECTIVE: Lack of judicious testing can result in the incorrect diagnosis of Clostridioides difficile infection (CDI), unnecessary CDI treatment, increased costs and falsely augmented hospital-acquired infection (HAI) rates. We evaluated facility-wide interventions used at the VA San Diego Healthcare System (VASDHS) to reduce healthcare-onset, healthcare-facility-associated CDI (HO-HCFA CDI), including the use of diagnostic stewardship with test ordering criteria. DESIGN: We conducted a retrospective study to assess the effectiveness of measures implemented to reduce the rate of HO-HCFA CDI at the VASDHS from fiscal year (FY)2015 to FY2018. INTERVENTIONS: Measures executed in a stepwise fashion included a hand hygiene initiative, prompt isolation of CDI patients, enhanced terminal room cleaning, reduction of fluoroquinolone and proton-pump inhibitor use, laboratory rejection of solid stool samples, and lastly diagnostic stewardship with C. difficile toxin B gene nucleic acid amplification testing (NAAT) criteria instituted in FY2018. RESULTS: From FY2015 to FY2018, 127 cases of HO-HCFA CDI were identified. All rate-reducing initiatives resulted in decreased HO-HCFA cases (from 44 to 13; P ≤ .05). However, the number of HO-HCFA cases (34 to 13; P ≤ .05), potential false-positive testing associated with colonization and laxative use (from 11 to 4), hospital days (from 596 to 332), CDI-related hospitalization costs (from $2,780,681 to $1,534,190) and treatment cost (from $7,158 vs $1,476) decreased substantially following the introduction of diagnostic stewardship with test criteria from FY2017 to FY2018. CONCLUSIONS: Initiatives to decrease risk for CDI and diagnostic stewardship of C. difficile stool NAAT significantly reduced HO-HCFA CDI rates, detection of potential false-positives associated with laxative use, and lowered healthcare costs. Diagnostic stewardship itself had the most dramatic impact on outcomes observed and served as an effective tool in reducing HO-HCFA CDI rates.


Subject(s)
Bacterial Toxins , Clostridioides difficile , Clostridium Infections , Cross Infection , Clostridioides , Clostridium Infections/diagnosis , Clostridium Infections/drug therapy , Clostridium Infections/epidemiology , Cross Infection/diagnosis , Cross Infection/drug therapy , Cross Infection/prevention & control , Health Expenditures , Hospitals , Humans , Retrospective Studies
15.
Mol Cancer ; 9: 316, 2010 Dec 20.
Article in English | MEDLINE | ID: mdl-21172016

ABSTRACT

BACKGROUND: Lymph node metastasis constitutes a key event in tumor progression. The molecular control of this process is poorly understood. Heparan sulfate is a linear polysaccharide consisting of unique sulfate-modified disaccharide repeats that allow the glycan to bind a variety of proteins, including chemokines. While some chemokines may drive lymphatic trafficking of tumor cells, the functional and genetic importance of heparan sulfate as a possible mediator of chemokine actions in lymphatic metastasis has not been reported. RESULTS: We applied a loss-of-function genetic approach employing lymphatic endothelial conditional mutations in heparan sulfate biosynthesis to study the effects on tumor-lymphatic trafficking and lymph node metastasis. Lymphatic endothelial deficiency in N-deacetylase/N-sulfotransferase-1 (Ndst1), a key enzyme involved in sulfating nascent heparan sulfate chains, resulted in altered lymph node metastasis in tumor-bearing gene targeted mice. This occurred in mice harboring either a pan-endothelial Ndst1 mutation or an inducible lymphatic-endothelial specific mutation in Ndst1. In addition to a marked reduction in tumor metastases to the regional lymph nodes in mutant mice, specific immuno-localization of CCL21, a heparin-binding chemokine known to regulate leukocyte and possibly tumor-cell traffic, showed a marked reduction in its ability to associate with tumor cells in mutant lymph nodes. In vitro modified chemotaxis studies targeting heparan sulfate biosynthesis in lymphatic endothelial cells revealed that heparan sulfate secreted by lymphatic endothelium is required for CCL21-dependent directional migration of murine as well as human lung carcinoma cells toward the targeted lymphatic endothelium. Lymphatic heparan sulfate was also required for binding of CCL21 to its receptor CCR7 on tumor cells as well as the activation of migration signaling pathways in tumor cells exposed to lymphatic conditioned medium. Finally, lymphatic cell-surface heparan sulfate facilitated receptor-dependent binding and concentration of CCL21 on the lymphatic endothelium, thereby serving as a mechanism to generate lymphatic chemokine gradients. CONCLUSIONS: This work demonstrates the genetic importance of host lymphatic heparan sulfate in mediating chemokine dependent tumor-cell traffic in the lymphatic microenvironment. The impact on chemokine dependent lymphatic metastasis may guide novel therapeutic strategies.


Subject(s)
Endothelial Cells/metabolism , Heparitin Sulfate/metabolism , Lymphatic Metastasis/physiopathology , Animals , Blotting, Western , Cell Line, Tumor , Cell Movement/drug effects , Cell Movement/genetics , Cells, Cultured , Chemokine CCL21/metabolism , Chromatography, Affinity , Culture Media, Conditioned/chemistry , Culture Media, Conditioned/pharmacology , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique , Humans , Immunohistochemistry , Lymphatic Metastasis/genetics , Mice , Reverse Transcriptase Polymerase Chain Reaction , Sulfotransferases/genetics
16.
Int J Pharm Pract ; 18(2): 100-7, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20441119

ABSTRACT

OBJECTIVE: The aim was to measure patient satisfaction with the Pharmacy Specialty Immunization Clinic (PSIC), a pharmacist-run vaccination clinic. METHODS: Patient satisfaction was measured using a non-validated instrument containing 10 items with a five-point Likert scale (strongly agree, agree, not sure, disagree and strongly disagree). Patients who were seen at the PSIC and who received at least one vaccination were eligible to take part in the patient satisfaction survey. Priority index, a method used to identify areas where limited resources can be used to maximize patient satisfaction, was calculated for the different items of the instrument to determine areas for quality improvement. This study was conducted at the Veterans Affairs San Diego Healthcare System (VASDHS). KEY FINDINGS: A total of 188 (55.1%) out of 341 patients who received at least one vaccine in the PSIC completed the survey. Prior to any encounter with the PSIC, patients perceived that the VASDHS was doing a good job providing vaccinations (92.5% answered agree or strongly agree). This perception continued when asked about overall satisfaction after receiving vaccination through the PSIC (86.9% answered agree or strongly agree). When asked about the time the pharmacist spent with the patient, nearly all answered that the pharmacist spent as much time as necessary (97.8% answered agree or strongly agree). Patient satisfaction with pharmacist counselling was equally well received and reflected good communication between patient and pharmacist (97.8% answered agree or strongly agree). In regard to pharmacist competency, 98.9% (n = 184) of patients agreed that pharmacists in the PSIC administered vaccinations appropriately. Priority index identified access to the vaccine as an area where performance-improvement efforts should be committed to improve patient satisfaction. CONCLUSIONS: Patients perceived good overall satisfaction with the pharmacist-run immunization clinic in terms of professionalism and access to vaccination. Priority index identified access to vaccination as a focus for future quality improvement.


Subject(s)
Immunization Programs/standards , Patient Satisfaction , Pharmaceutical Services/standards , Pharmacists/standards , Aged , Aged, 80 and over , Ambulatory Care Facilities , Clinical Competence , Data Collection , Female , Health Services Accessibility , Humans , Immunization Programs/organization & administration , Male , Middle Aged , Patient Education as Topic/methods , Patient Education as Topic/standards , Pharmaceutical Services/organization & administration , Pharmacists/organization & administration , United States , United States Department of Veterans Affairs
17.
Neoplasia ; 22(2): 86-97, 2020 02.
Article in English | MEDLINE | ID: mdl-31896526

ABSTRACT

While recent research points to the importance of glycans in cancer immunity, knowledge on functional mechanisms is lacking. In lung carcinoma among other tumors, anti-tumor immunity is suppressed; and while some recent therapies boost T-cell mediated immunity by targeting immune-checkpoint pathways, robust responses are uncommon. Augmenting tumor antigen-specific immune responses by endogenous dendritic cells (DCs) is appealing from a specificity standpoint, but challenging. Here, we show that restricting a heparan sulfate (HS) loss-of-function mutation in the HS sulfating enzyme Ndst1 to predominantly conventional DCs (Ndst1f/f CD11cCre+ mutation) results in marked inhibition of Lewis lung carcinoma growth along with increased tumor-associated CD8+ T cells. In mice deficient in a major DC HS proteoglycan (syndecan-4), splenic CD8+ T cells showed increased anti-tumor cytotoxic responses relative to controls. Studies examining Ndst1f/f CD11cCre + mutants revealed that mutation was associated with an increase in anti-tumor cytolysis using either splenic CD8+ T cells or tumor-infiltrating (TIL) CD8+ T cells purified ex-vivo, and tested in pooled effector-to-target cytolytic assays against tumor cells from respective animals. On glycan compositional analysis, HS purified from Ndst1f/f CD11cCre + mutant DCs had reduced overall sulfation, including reduced sulfation of a tri-sulfated disaccharide species that was intriguingly abundant on wildtype DC HS. Interestingly, antigen presentation in the context of major histocompatibility complex class-I (MHC-I) was enhanced in mutant DCs, with more striking effects in the setting of HS under-sulfation, pointing to a likely regulatory role by sulfated glycans at the antigen/MHC-I - T-cell interface; and possibly future opportunities to improve antigen-specific T cell responses by immunologic targeting of HS proteoglycans in cancer.


Subject(s)
Carcinoma, Lewis Lung/drug therapy , Major Histocompatibility Complex/genetics , Polysaccharides/genetics , Proteoglycans/genetics , Sulfotransferases/genetics , Animals , CD11c Antigen/genetics , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/immunology , Carcinoma, Lewis Lung/genetics , Carcinoma, Lewis Lung/immunology , Carcinoma, Lewis Lung/pathology , Dendritic Cells/immunology , Dendritic Cells/pathology , Heparitin Sulfate/pharmacology , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/immunology , Humans , Immunity, Cellular/genetics , Immunity, Cellular/immunology , Loss of Function Mutation/genetics , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Major Histocompatibility Complex/immunology , Mice , Polysaccharides/antagonists & inhibitors , Proteoglycans/antagonists & inhibitors , Proteoglycans/immunology , T-Lymphocytes/immunology , T-Lymphocytes/pathology
18.
Article in English | MEDLINE | ID: mdl-31025885

ABSTRACT

Objective: Susceptibility-weighted imaging (SWI) has been used to identify neurodegeneration in amyotrophic lateral sclerosis (ALS) through qualitative gross visual comparison of signal intensity. The aim of this study was to quantitatively identify cerebral degeneration in ALS on SWI using texture analysis. Methods: SW images were acquired from 17 ALS patients (58.4 ± 10.3 years, 13M/4F, ALSFRS-R 41.2 ± 4.1) and 18 healthy controls (56.3 ± 17.6 years, 9M/9F) at 4.7 tesla. Textures were computed within the precentral gyrus and basal ganglia and compared between patients and controls using ANCOVA with age and gender as covariates. Texture features were correlated with clinical measures in patients. Texture features found to be significantly different between patients and controls in the precentral gyrus were then used in a whole-brain 3D texture analysis. Results: The texture feature autocorrelation was significantly higher in ALS patients compared to healthy controls in the precentral gyrus and basal ganglia (p < 0.05). Autocorrelation correlated significantly with clinical measures such as disease progression rate and finger tapping speed (p < 0.05). Whole brain 3D texture analysis using autocorrelation revealed differences between ALS patients and controls within the precentral gyrus on SWI images (p < 0.001). Conclusion: Texture analysis on SWI can quantitatively identify cerebral differences between ALS patients and controls.


Subject(s)
Amyotrophic Lateral Sclerosis/diagnostic imaging , Brain/diagnostic imaging , Disease Progression , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Adult , Aged , Amyotrophic Lateral Sclerosis/metabolism , Brain/metabolism , Cohort Studies , Female , Humans , Male , Middle Aged , Multimodal Imaging/methods , Prospective Studies
19.
AIDS Res Hum Retroviruses ; 34(7): 603-606, 2018 07.
Article in English | MEDLINE | ID: mdl-29661022

ABSTRACT

Herpes zoster (HZ) occurs at a higher age-specific rate in people living with HIV (PLWH) than in the general population. We implemented a quality improvement study to assess herpes zoster vaccine (HZV) usage among PLWH, assess HZV usage after additional reminders/prompts, and identify barriers to HZV among older PLWH. HZV rates in PLWH were determined in six institutions with varying payment structures. For the intervention, Part 1, PLWH eligible for HZV at the University of Colorado were identified, and providers were notified of patient eligibility. In Part 2, in addition to provider notification, an order for HZV was placed in the patient's chart before a clinic appointment. HZ vaccination rates ranged from 1.5% to 42.4% at six sites. Before the intervention, 21.3% of eligible University of Colorado patients had received HZV. An additional 8.3% received HZV with Part 1 and 17.8% with Part 2 interventions. At completion, a total of 53.2% of eligible patients had received HZV through routine clinical care or the interventions. Insurance coverage concern was cited as a common reason for not receiving HZV. Minor adverse reactions occurred in 26.7% patients and did not require medical care. HZV coverage was low at a majority of sites. Clinical reminders with links to vaccination orders or preplaced vaccination orders led to improved HZV coverage in our clinic, but published guidelines for use of HZV in PLWH and improvement in logistic or insurance barriers to HZV receipt are paramount to improved HZV coverage.


Subject(s)
HIV Infections/complications , Herpes Zoster Vaccine/administration & dosage , Herpes Zoster/prevention & control , Vaccination Coverage , Aged , Aged, 80 and over , Colorado , Female , Health Services Accessibility , Humans , Male , Middle Aged
20.
IDCases ; 10: 65-67, 2017.
Article in English | MEDLINE | ID: mdl-28951848

ABSTRACT

INTRODUCTION: Aureobasidium pullulans is a saprophytic fungus that is widely distributed in the environment, and in the right host can be an opportunistic human pathogen. PRESENTATION OF CASE: A 66-year-old man with Crohn's disease with a single kidney, and requiring total parenteral nutrition via a Hickman catheter, was admitted with a 10-week history of progressive shortness of breath, fevers and weight loss. Chest imaging demonstrated new multifocal lung parenchymal opacities compatible with septic pulmonary emboli. Blood culture grew a yeast-like organism that transformed into a black mold on subculture, eventually identified as A. pullulans. Due to triazole resistance, the patient was treated with liposomal amphotericin and micafungin. Serum (1,3)-ß-d-glucan level was used to monitor therapy, initially measured at >500 pg/mL and decreasing to 66 pg/mL after one year of therapy. DISCUSSION: We describe the successful treatment of a case of catheter related fungemia and septic pulmonary emboli due A. pullulans. While initially appearing as an oval yeast on blood culture, subsequent growth as a black mold led to identification of the fungus as A. pullulans. The infection was cured with a combination of antifungal agents, even though the foreign body could not be safely removed. Nephrotoxicity required dosing adjustment of the amphotericin to biweekly during the maintenance phase of treatment. The serum (1,3)-ß-d-glucan level proved to be useful in monitoring response to therapy. CONCLUSION: We report here successful treatment of a disseminated A. pullulans infection with an induction and maintenance approach to liposomal amphotericin dosing, and monitoring response to therapy with serum (1,3)-ß-d-glucan levels.

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