scholarly journals Neutrophils Are Required During Immunization With the Pneumococcal Conjugate Vaccine for Protective Antibody Responses and Host Defense Against Infection

2020 ◽  
Vol 222 (8) ◽  
pp. 1363-1370 ◽  
Author(s):  
Essi Y I Tchalla ◽  
Manmeet Bhalla ◽  
Elizabeth A Wohlfert ◽  
Elsa N Bou Ghanem
Keyword(s):  
Conjugate Vaccine ◽  
Survival Rates ◽  
Antibody Responses ◽  
Host Protection ◽  
Lethal Infection ◽  
Neutrophil Depletion ◽  
Opsonophagocytic Killing ◽  
Full Protection

Abstract Neutrophils can shape adaptive immunity; however, their role in vaccine-induced protection against infections in vivo remains unclear. Here, we tested their role in the clinically relevant polysaccharide conjugate vaccine against Streptococcus pneumoniae (pneumococcus). We antibody depleted neutrophils during vaccination, allowed them to recover, and 4 weeks later challenged mice with pneumococci. We found that while isotype-treated vaccinated controls were protected against an otherwise lethal infection in naive mice, full protection was lost upon neutrophil depletion. Compared to vaccinated controls, neutrophil-depleted mice had higher lung bacterial burdens, increased incidence of bacteremia, and lower survival rates. Sera from neutrophil-depleted mice had less antipneumococcal IgG2c and IgG3, were less efficient at inducing opsonophagocytic killing of bacteria by neutrophils in vitro, and were worse at protecting naive mice against pneumococcal pneumonia. In summary, neutrophils are required during vaccination for optimal host protection, which has important implications for future vaccine design against pneumococci and other pathogens.

scholarly journals Neutrophils are required during immunization with the pneumococcal conjugate vaccine for protective antibody responses and host defense against infection

2020 ◽  
Author(s):  
Essi Y. I. Tchalla ◽  
Elizabeth A. Wohlfert ◽  
Elsa N. Bou Ghanem
Keyword(s):  
Conjugate Vaccine ◽  
Survival Rates ◽  
Antibody Responses ◽  
Host Protection ◽  
Lethal Infection ◽  
Neutrophil Depletion ◽  
Opsonophagocytic Killing ◽  
Full Protection

AbstractNeutrophils can shape adaptive immunity, however their role in vaccine-induced protection against infections in vivo remains unclear. Here, we tested their role in the clinically relevant polysaccharide conjugate vaccine against Streptococcus pneumoniae (pneumococcus). We antibody depleted neutrophils during vaccination, allowed them to recover, and four weeks later challenged mice with pneumococci. We found that while isotype-treated vaccinated controls were protected against an otherwise lethal infection in naïve mice, full protection was lost upon neutrophil depletion. Compared to vaccinated controls, neutrophil-depleted mice had higher lung bacterial burdens, increased incidence of bacteremia and lower survival rates. Sera from neutrophil-depleted mice had less anti-pneumococcal IgG2c and IgG3, were less efficient at inducing opsonophagocytic killing of bacteria by neutrophils in vitro and worse at protecting naïve mice against pneumococcal pneumonia. In summary, neutrophils are required during vaccination for optimal host protection, which has important implications for future vaccine design against pneumococci and other pathogens.

scholarly journals Effects of Vitrification on the Blastocyst Gene Expression Profile in a Porcine Model

2021 ◽  
Vol 22 (3) ◽  
pp. 1222
Author(s):  
Cristina Cuello ◽  
Cristina A. Martinez ◽  
Josep M. Cambra ◽  
Inmaculada Parrilla ◽  
Heriberto Rodriguez-Martinez ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Expression Analysis ◽  
Survival Rates ◽  
Control Group ◽  
P Value ◽  
Transcriptome Profile ◽  
Embryo Viability ◽  
The Impact

This study was designed to investigate the impact of vitrification on the transcriptome profile of blastocysts using a porcine (Sus scrofa) model and a microarray approach. Blastocysts were collected from weaned sows (n = 13). A total of 60 blastocysts were vitrified (treatment group). After warming, vitrified embryos were cultured in vitro for 24 h. Non-vitrified blastocysts (n = 40) were used as controls. After the in vitro culture period, the embryo viability was morphologically assessed. A total of 30 viable embryos per group (three pools of 10 from 4 different donors each) were subjected to gene expression analysis. A fold change cut-off of ±1.5 and a restrictive threshold at p-value < 0.05 were used to distinguish differentially expressed genes (DEGs). The survival rates of vitrified/warmed blastocysts were similar to those of the control (nearly 100%, n.s.). A total of 205 (112 upregulated and 93 downregulated) were identified in the vitrified blastocysts compared to the control group. The vitrification/warming impact was moderate, and it was mainly related to the pathways of cell cycle, cellular senescence, gap junction, and signaling for TFGβ, p53, Fox, and MAPK. In conclusion, vitrification modified the transcriptome of in vivo-derived porcine blastocysts, resulting in minor gene expression changes.

scholarly journals Evaluation of a Novel Therapeutic Approach to Treating Severe Pneumococcal Infection Using a Mouse Model

2009 ◽  
Vol 16 (6) ◽  
pp. 806-810 ◽  
Author(s):  
Nikkol Melnick ◽  
Gowrisankar Rajam ◽  
George M. Carlone ◽  
Jacquelyn S. Sampson ◽  
Edwin W. Ades
Keyword(s):  
Single Dose ◽  
Combination Therapy ◽  
Polymorphonuclear Leukocytes ◽  
Low Dose ◽  
Control Level ◽  
Pneumococcal Infection ◽  
Amino Acid Peptide ◽  
Opsonophagocytic Killing

ABSTRACT P4, a 28-amino-acid peptide, is a eukaryotic cellular activator that enhances specific in vitro opsonophagocytic killing of multiple bacterial pathogens. In a previous study, we successfully recreated this phenomenon in mice in vivo by using a two-dose regimen of P4 and pathogen-specific antibodies, which significantly reduced moribundity in mice. For the present study, we hypothesized that the inclusion of a low-dose antibiotic would make it possible to treat the infected mice with a single dose containing a mixture of P4 and a pathogen-specific antibody. A single dose consisting of P4, intravenous immunoglobulin (IVIG), and ceftriaxone effectively reduced moribundity compared to that of untreated controls (n = 10) by 75% (P < 0.05) and rescued all (10 of 10) infected animals (P < 0.05). If rescued animals were reinfected with Streptococcus pneumoniae and treated with a single dose containing P4, IVIG, and ceftriaxone, they could be rerescued. This observation of the repeated successful use of P4 combination therapy demonstrates a low risk of tolerance development. Additionally, we examined the polymorphonuclear leukocytes (PMN) derived from infected mice and observed that P4 enhanced in vitro opsonophagocytic killing (by >80% over the control level; P < 0.05). This finding supports our hypothesis that PMN are activated by P4 during opsonophagocytosis and the recovery of mice from pneumococcal infection. P4 peptide-based combination therapy may offer an alternative and rapid immunotherapy to treat fulminant pneumococcal infection.

scholarly journals 766 Toward safe, systemic delivery of synthetic TLR7/8 agonists using Bottlebrush Prodrugs (BPDs)

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A801-A801
Author(s):  
Sachin Bhagchandani ◽  
Lauren Milling ◽  
Bin Liu ◽  
Timothy Fessenden ◽  
Stefani Spranger ◽  
...  
Keyword(s):  
Survival Rates ◽  
Immunomodulatory Activity ◽  
Systemic Delivery ◽  
Antibody Treatment ◽  
Tlr Agonists ◽  
Cytokine Levels ◽  
Systemic Side Effects ◽  
Tolerable Dose

BackgroundAlthough toll-like receptor (TLR) agonists such as imidazoquinoline derivatives (IMDs) have been well researched and are FDA approved as topical solutions for treatment of skin cancer, their systemic delivery for treatment of metastatic disease has not been successful due to toxicity issues. Therefore, to lessen the degree of the adverse effects of intravenous delivery of IMDs such as resiquimod (R848), a bottlebrush prodrug (BPD) system enabling controlled release of R848 at tunable rates was designed and synthesized. We hypothesized that this approach would allow for minimizing the release of the free drug in serum, allowing for a higher concentration to accumulate in the tumor while minimizing systemic side effects.MethodsR848 was conjugated to a bottlebrush polymer with different linkers designed to precisely tune the R848 release rate. The release rates of the drug delivered through this system were first tested in PBS. These prodrug formulations were validated for drug activity in vitro in mouse and human TLR reporter cells. The maximum tolerable dose was defined by monitoring weight loss and serum cytokine levels upon intravenous administration at multiple concentrations. Finally, anti-tumor efficacy of the BPD system was tested in vivo using the MC38 colon cancer model as a monotherapy and in combination with anti-PD-1 antibody treatment.ResultsThe in-vitro half-lives of the conjugated drugs varied from a few days to over a month when tested in PBS. The different BPDs demonstrated linker dependent TLR activation upon culturing with TLR reporter cells validating the immunomodulatory activity of R848. It was found that the R848-BPDs, which accumulated at the tumor site over time, significantly delayed tumor growth and improved survival rates, which was further enhanced when used in combination with anti-PD-1.ConclusionsOverall, our research suggests that our R848-BPD platform allows for safe, systemic delivery of TLR agonists to activate the immune system in treatment of cancer.

scholarly journals ISGylation drives basal breast tumour progression by promoting EGFR recycling and Akt signalling

2019 ◽  
Author(s):  
Alfonso Bolado-Carrancio ◽  
Morwenna Muir ◽  
Ailith Ewing ◽  
Kenneth Macleod ◽  
William Gallagher ◽  
...  
Keyword(s):  
Egf Receptor ◽  
Tumour Progression ◽  
Survival Rates ◽  
Breast Tumour ◽  
Breast Cancers ◽  
Breast Cancer Patients ◽  
Akt Activation ◽  
Gdp Dissociation Inhibitor

ABSTRACTISG15 is an ubiquitin-like modifier that is associated with reduced survival rates in breast cancer patients. However, the mechanism by which ISG15 achieves this remains elusive. We demonstrate that modification of Rab GDP-Dissociation Inhibitor Beta (GDI2) by ISG15 (ISGylation) alters endocytic recycling of the EGF receptor (EGFR). By regulating EGFR trafficking, ISGylation sustains Akt-signalling in vitro and in vivo. Persistent and enhanced Akt activation explains the more aggressive tumour behaviour observed in animal models and human breast cancers. We show that ISGylation can act as driver of tumour progression rather than merely being a marker of it.

Arthrospira Platensis Mediated Green Biosynthesis of Silver Nanoparticlesas Breast Cancer Controlling Agent: In-vitro and In-vivo Safety Approach.

2021 ◽  
Author(s):  
Nehal El Deeb ◽  
Mai A. Abo-Eleneen ◽  
Omyma A. Awad ◽  
Atef M. Abo-Shady
Keyword(s):  
Breast Cancer ◽  
Survival Rates ◽  
Arthrospira Platensis ◽  
Active Metabolites ◽  
Protein Marker ◽  
Anticancer Efficacy ◽  
Protein Levels ◽  
Albino Mice

Abstract Biogenic Silver Nanoparticle (bio-AgNPs) is one of the most fascinating nanomaterials used in the biomedical purposes. In the current study, we biosynthesized AgNPs (bio-AgNPs) using Arthrospira platensis(A-bio-AgNPs), Microcystis aeruginosa(M-bio-AgNPs)and Chlorella vulgaris(C-bio-AgNPs) active metabolites and evaluated their anticancer efficacy against breast cancer. The recovered bio-AgNPs were characterized using Scanning and Transmission Electron Microscopy (SEM and TEM) and their safety profiles were monitoring in-vitro on PBMCs cells and in-vivo on Albino mice. The obtained results indicated the safety usage of bio-AgNPs at concentration of 0.1 mg/ml on PBMCs cells and 1.5mg/ml on the Albino mice. The bio-AgNPs displayed dose-dependent cytotoxic effects against HepG-2, CaCO-2 and MCF-7 cell lines by inducing ROS and arresting the treated cells in G0/G1 and sub G0 phases. In addition, A-bio-AgNPs induced breast cancer cellular apoptosis by down regulating the expression of survivin, MMP7, TGF and Bcl2 genes. Upon A-bio-AgNPs treatment, a significant reduction in tumor growth and prolonged survival rates were recorded in breast cancer BALB/c model. Furthermore, A-bio-AgNPs treatment significant decreased theKi 67 protein marker from 60% (in the untreated group) to 20% and increased Caspase 3 protein levels to 65% (in treated groups) comparing with 45% (in Doxorubicin treated groups).

scholarly journals Polystyrene nanoplastics accumulate in ZFL cell lysosomes and in zebrafish larvae after acute exposure, inducing a synergistic immune response in vitro without affecting larval survival in vivo

2020 ◽  
Vol 7 (8) ◽  
pp. 2410-2422
Author(s):  
Irene Brandts ◽  
Marlid Garcia-Ordoñez ◽  
Lluis Tort ◽  
Mariana Teles ◽  
Nerea Roher
Keyword(s):  
Immune Response ◽  
Larval Survival ◽  
Liver Cells ◽  
Acute Exposure ◽  
Zebrafish Larvae ◽  
Lethal Infection ◽  
Zebrafish Liver ◽  
Immune Response In Vitro

Polystyrene nanoplastics are internalized in zebrafish liver cells, accumulating in lysosomes, and in zebrafish larvae but do not affect the larval suvival to a lethal infection.

scholarly journals The polypeptide GALNT6 Displays Redundant Functions upon Suppression of its Closest Homolog GALNT3 in Mediating Aberrant O-Glycosylation, Associated with Ovarian Cancer Progression

2019 ◽  
Vol 20 (9) ◽  
pp. 2264 ◽  
Author(s):  
Razan Sheta ◽  
Magdalena Bachvarova ◽  
Elizabeth Macdonald ◽  
Stephane Gobeil ◽  
Barbara Vanderhyden ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cancer Progression ◽  
Molecular Mechanisms ◽  
Survival Rates ◽  
Functional Redundancy ◽  
Tumor Formation ◽  
Migration And Invasion ◽  
Gene Ablation

Epithelial ovarian cancer (EOC) represents the most lethal gynecologic malignancy; a better understanding of the molecular mechanisms associated with EOC etiology could substantially improve EOC management. Aberrant O-glycosylation in cancer is attributed to alteration of N-acetylgalactosaminyltransferases (GalNAc-Ts). Reports suggest a genetic and functional redundancy between GalNAc-Ts, and our previous data are indicative of an induction of GALNT6 expression upon GALNT3 suppression in EOC cells. We performed single GALNT3 and double GALNT3/T6 suppression in EOC cells, using a combination of the CRISPR-Cas9 system and shRNA-mediated gene silencing. The effect of single GALNT3 and double GALNT3/T6 inhibition was monitored both in vitro (on EOC cells roliferation, migration, and invasion) and in vivo (on tumor formation and survival of experimental animals). We confirmed that GALNT3 gene ablation leads to strong and rather compensatory GALNT6 upregulation in EOC cells. Moreover, double GALNT3/T6 suppression was significantly associated with stronger inhibitory effects on EOC cell proliferation, migration, and invasion, and accordingly displayed a significant increase in animal survival rates compared with GALNT3-ablated and control (Ctrl) EOC cells. Our data suggest a possible functional redundancy of GalNAc-Ts (GALNT3 and T6) in EOC, with the perspective of using both these enzymes as novel EOC biomarkers and/or therapeutic targets.

scholarly journals Inhibition of LpxC Protects Mice from Resistant Acinetobacter baumannii by Modulating Inflammation and Enhancing Phagocytosis

mBio ◽  
2012 ◽  
Vol 3 (5) ◽  
Author(s):  
Lin Lin ◽  
Brandon Tan ◽  
Paul Pantapalangkoor ◽  
Tiffany Ho ◽  
Beverlie Baquir ◽  
...  
Keyword(s):  
Acinetobacter Baumannii ◽  
Gram Negative ◽  
Content Type ◽  
Novel Treatments ◽  
New Class ◽  
Virulent Strains ◽  
Lethal Infection ◽  
Tlr4 Activation ◽  
Opsonophagocytic Killing

ABSTRACT New treatments are needed for extensively drug-resistant (XDR) Gram-negative bacilli (GNB), such as Acinetobacter baumannii. Toll-like receptor 4 (TLR4) was previously reported to enhance bacterial clearance of GNB, including A. baumannii. However, here we have shown that 100% of wild-type mice versus 0% of TLR4-deficient mice died of septic shock due to A. baumannii infection, despite having similar tissue bacterial burdens. The strain lipopolysaccharide (LPS) content and TLR4 activation by extracted LPS did not correlate with in vivo virulence, nor did colistin resistance due to LPS phosphoethanolamine modification. However, more-virulent strains shed more LPS during growth than less-virulent strains, resulting in enhanced TLR4 activation. Due to the role of LPS in A. baumannii virulence, an LpxC inhibitor (which affects lipid A biosynthesis) antibiotic was tested. The LpxC inhibitor did not inhibit growth of the bacterium (MIC > 512 µg/ml) but suppressed A. baumannii LPS-mediated activation of TLR4. Treatment of infected mice with the LpxC inhibitor enhanced clearance of the bacteria by enhancing opsonophagocytic killing, reduced serum LPS concentrations and inflammation, and completely protected the mice from lethal infection. These results identify a previously unappreciated potential for the new class of LpxC inhibitor antibiotics to treat XDR A. baumannii infections. Furthermore, they have far-reaching implications for pathogenesis and treatment of infections caused by GNB and for the discovery of novel antibiotics not detected by standard in vitro screens. IMPORTANCE Novel treatments are needed for infections caused by Acinetobacter baumannii, a Gram-negative bacterium that is extremely antibiotic resistant. The current study was undertaken to understand the immunopathogenesis of these infections, as a basis for defining novel treatments. The primary strain characteristic that differentiated virulent from less-virulent strains was shedding of Gram-negative lipopolysaccharide (LPS) during growth. A novel class of antibiotics, called LpxC inhibitors, block LPS synthesis, but these drugs do not demonstrate the ability to kill A. baumannii in vitro. We found that an LpxC inhibitor blocked the ability of bacteria to activate the sepsis cascade, enhanced opsonophagocytic killing of the bacteria, and protected mice from lethal infection. Thus, an entire new class of antibiotics which is already in development has heretofore-unrecognized potential to treat A. baumannii infections. Furthermore, standard antibiotic screens based on in vitro killing failed to detect this treatment potential of LpxC inhibitors for A. baumannii infections.

scholarly journals Two-stage nanoparticle delivery of piperlongumine and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) anti-cancer therapy

TECHNOLOGY ◽  
2016 ◽  
Vol 04 (01) ◽  
pp. 60-69 ◽  
Author(s):  
Charles C. Sharkey ◽  
Jiahe Li ◽  
Sweta Roy ◽  
Qianhui Wu ◽  
Michael R. King
Keyword(s):  
Cancer Cells ◽  
Survival Rates ◽  
Xenograft Model ◽  
Plga Nanoparticles ◽  
Mouse Xenograft Model ◽  
Anti Cancer ◽  
In Vivo Testing ◽  
Hct116 Cells

This study outlines a drug delivery mechanism that utilizes two independent vehicles, allowing for delivery of chemically and physically distinct agents. The mechanism was utilized to deliver a new anti-cancer combination therapy consisting of piperlongumine (PL) and TRAIL to treat PC3 prostate cancer and HCT116 colon cancer cells. PL, a small-molecule hydrophobic drug, was encapsulated in poly (lactic-co-glycolic acid) (PLGA) nanoparticles. TRAIL was chemically conjugated to the surface of liposomes. PL was first administered to sensitize cancer cells to the effects of TRAIL. PC3 and HCT116 cells had lower survival rates in vitro after receiving the dual nanoparticle therapy compared to each agent individually. In vivo testing involved a subcutaneous mouse xenograft model using NOD-SCID gamma mice and HCT116 cells. Two treatment cycles were administered over 48 hours. Higher apoptotic rates were observed for HCT116 tumor cells that received the dual nanoparticle therapy compared to individual stages of the nanoparticle therapy alone.

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