The human α-defensin-derived peptide HD5(1-9) inhibits cellular attachment and entry of human cytomegalovirus

2019 ◽  
Author(s):  
Rebecca Böffert ◽  
Ramona Businger ◽  
Hannes Preiß ◽  
Dirk Ehmann ◽  
Vincent Truffault ◽  
...  

ABSTRACTHuman cytomegalovirus (HCMV) infection causes severe illness in newborns and immunocompromised patients. Since treatment options are limited there is an unmet need for new therapeutic approaches. Defensins are cationic peptides, produced by various human tissues, which serve as antimicrobial effectors of the immune system. Furthermore, some defensins are proteolytically cleaved, resulting in the generation of smaller fragments with increased activity. Together, this led us to hypothesize that defensin-derived peptides are natural human inhibitors of virus infection with low toxicity. We screened several human defensin HNP4- and HD5-derived peptides and found HD5(1-9) to be antiviral without toxicity at high concentrations. HD5(1-9) inhibited HCMV cellular attachment and thereby entry and was active against primary as well as a multiresistant HCMV isolate. Moreover, cysteine and arginine residues were identified to mediate the antiviral activity of HD5(1-9). Altogether, defensin-derived peptides, in particular HD5(1-9), qualify as promising candidates for further development as a novel class of HCMV entry inhibitors.AUTHOR SUMMARYDefensins are peptides produced by various human organs which take part in the natural defense against pathogens. Recently, it has been shown that defensins are further cleaved to smaller peptides that have high intrinsic anti-microbial activity. We here challenged the hypothesis that these peptides might have antiviral activity, and due to their presumably natural occurrence, low toxicity. Indeed, we found one peptide fragment that turned out to block the attachment of the human cytomegalovirus (HCMV) to cells. Furthermore, this peptide did not show toxicity in various cellular assays or impede the embryonic development of zebrafish at the concentrations used to block HCMV. This is important, since HCMV is one of the most important viral congenital infections. Altogether, our results hold promise for the development of a new class of antivirals against HCMV.

Cancers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1715
Author(s):  
Robin Park ◽  
Laercio Lopes ◽  
Anwaar Saeed

Advanced gastroesophageal cancer (GEC) has a poor prognosis and limited treatment options. Immunotherapy including the anti-programmed death-1 (PD-1) antibodies pembrolizumab and nivolumab have been approved for use in various treatment settings in GEC. Additionally, frontline chemoimmunotherapy regimens have recently demonstrated promising efficacy in large phase III trials and have the potential to be added to the therapeutic armamentarium in the near future. There are currently several immunotherapy biomarkers that are validated for use in the clinical setting for GEC including programmed death ligand-1 (PD-L1) expression as well as the tumor agnostic biomarkers such as mismatch repair or microsatellite instability (MMR/MSI) and tumor mutational burden (TMB). However, apart from MMR/MSI, these biomarkers are imperfect because none are highly sensitive nor specific. Therefore, there is an unmet need for immunotherapy biomarker development. To this end, several biomarkers are currently being evaluated in ongoing trials with some showing promising predictive potential. Here, we summarize the landscape of immunotherapy predictive biomarkers that are currently being evaluated in GEC.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S617-S617
Author(s):  
Dan Smelter ◽  
Sue McCrone ◽  
Warren Rose

Abstract Background MSSA Infective endocarditis (IE) is inherently a high-burden infection with up to a 30% mortality rate. Cefazolin is an appealing treatment option for IE with low toxicity and a favorable dosing scheme. However, cefazolin has been associated with treatment failure in IE, attributed to an inoculum effect. The specific mechanism underlying the cefazolin inoculum effect (CIE) remains undetermined, but CIE has been linked to both blaZ expression and agr dysfunction. This study aims to determine whether CIE is linked to reduced susceptibility to other antibiotics and worse outcomes regardless of therapy in MSSA endovascular infections. Methods Sixty-four MSSA strains were collected from patients with endovascular infections not treated with cefazolin. To determine CIE phenotype, strains were cultured and MICs assayed for cefazolin, nafcillin, and vancomycin at 107 CFU/mL for high-inocula (HI) and 105 CFU/mL for standard-inocula (SI). This study defined CIE as a ≥ 4-fold increase in MIC at HI compared to SI, with at least an MIC of 4 mg/L at HI. Nitrocefin disks identified blaZ expression, and beta lysin disks were used to determine hemolysin type and agr function. Patient outcomes of mortality and bacteremia duration were assessed across cohorts. Results Twenty-four strains exhibit a CIE (38%), with 10 strains having an MIC of ≥ 32mg/L at HI. Nafcillin and vancomycin also had an inoculum effect, uncoupled from the CIE and occurring at a lower frequency and amplitude at HI. Presence of CIE had a greater association with blaZ expression (71% vs 25%) than agr dysfunction (38% vs 20%). 50% (9/18) of CIE infections were cleared within 48 hours while 77% (20/26) of CIE-negative infections were cleared within 48 hours (P=0.106). However, presence of CIE was not associated with increased mortality (25% CIE-positive vs 35%; P=0.578) Conclusion Previous studies for CIE failed to enrich for isolates from endovascular sources, where inocula are known to be high. This study presents one of the largest endovascular source cohorts for CIE evaluation. It identifies that CIE prevalence (38%) is higher than reports from diverse infection sources (10-36%). CIE appears to predict bacteremia duration with other MSSA treatment options, suggesting mechanisms independent of blaZ and agr function for this phenomenon. Disclosures Warren Rose, PharmD, MPH, Merck (Grant/Research Support)Paratek (Grant/Research Support)


BMJ Open ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. e045343
Author(s):  
Ray Moynihan ◽  
Sharon Sanders ◽  
Zoe A Michaleff ◽  
Anna Mae Scott ◽  
Justin Clark ◽  
...  

ObjectivesTo determine the extent and nature of changes in utilisation of healthcare services during COVID-19 pandemic.DesignSystematic review.EligibilityEligible studies compared utilisation of services during COVID-19 pandemic to at least one comparable period in prior years. Services included visits, admissions, diagnostics and therapeutics. Studies were excluded if from single centres or studied only patients with COVID-19.Data sourcesPubMed, Embase, Cochrane COVID-19 Study Register and preprints were searched, without language restrictions, until 10 August, using detailed searches with key concepts including COVID-19, health services and impact.Data analysisRisk of bias was assessed by adapting the Risk of Bias in Non-randomised Studies of Interventions tool, and a Cochrane Effective Practice and Organization of Care tool. Results were analysed using descriptive statistics, graphical figures and narrative synthesis.Outcome measuresPrimary outcome was change in service utilisation between prepandemic and pandemic periods. Secondary outcome was the change in proportions of users of healthcare services with milder or more severe illness (eg, triage scores).Results3097 unique references were identified, and 81 studies across 20 countries included, reporting on >11 million services prepandemic and 6.9 million during pandemic. For the primary outcome, there were 143 estimates of changes, with a median 37% reduction in services overall (IQR −51% to −20%), comprising median reductions for visits of 42% (−53% to −32%), admissions 28% (−40% to −17%), diagnostics 31% (−53% to −24%) and for therapeutics 30% (−57% to −19%). Among 35 studies reporting secondary outcomes, there were 60 estimates, with 27 (45%) reporting larger reductions in utilisation among people with a milder spectrum of illness, and 33 (55%) reporting no difference.ConclusionsHealthcare utilisation decreased by about a third during the pandemic, with considerable variation, and with greater reductions among people with less severe illness. While addressing unmet need remains a priority, studies of health impacts of reductions may help health systems reduce unnecessary care in the postpandemic recovery.PROSPERO registration numberCRD42020203729.


2020 ◽  
Vol 41 (S1) ◽  
pp. s59-s60
Author(s):  
Hannah E. Reses ◽  
Kelly Hatfield ◽  
Jesse Jacob ◽  
Chris Bower ◽  
Elisabeth Vaeth ◽  
...  

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB) is an important cause of healthcare-associated infections with limited treatment options and high mortality. To describe risk factors for mortality, we evaluated characteristics associated with 30-day mortality in patients with CRAB identified through the Emerging Infections Program (EIP). Methods: From January 2012 through December 2017, 8 EIP sites (CO, GA, MD, MN, NM, NY, OR, TN) participated in active, laboratory-, and population-based surveillance for CRAB. An incident case was defined as patient’s first isolation in a 30-day period of A. baumannii complex from sterile sites or urine with resistance to ≥1 carbapenem (excluding ertapenem). Medical records were abstracted. Patients were matched to state vital records to assess mortality within 30 days of incident culture collection. We developed 2 multivariable logistic regression models (1 for sterile site cases and 1 for urine cases) to evaluate characteristics associated with 30-day mortality. Results: We identified 744 patients contributing 863 cases, of which 185 of 863 cases (21.4%) died within 30 days of culture, including 113 of 257 cases (44.0%) isolated from a sterile site and 72 of 606 cases (11.9%) isolated from urine. Among 628 hospitalized cases, death occurred in 159 cases (25.3%). Among hospitalized fatal cases, death occurred after hospital discharge in 27 of 57 urine cases (47.4%) and 21 of 102 cases from sterile sites (20.6%). Among sterile site cases, female sex, intensive care unit (ICU) stay after culture, location in a healthcare facility, including a long-term care facility (LTCF), 3 days before culture, and diagnosis of septic shock were associated with increased odds of death in the model (Fig. 1). In urine cases, age 40–54 or ≥75 years, ICU stay after culture, presence of an indwelling device other than a urinary catheter or central line (eg, endotracheal tube), location in a LTCF 3 days before culture, diagnosis of septic shock, and Charlson comorbidity score ≥3 were associated with increased odds of mortality (Fig. 2). Conclusion: Overall 30-day mortality was high among patients with CRAB, including patients with CRAB isolated from urine. A substantial fraction of mortality occurred after discharge, especially among patients with urine cases. Although there were some differences in characteristics associated with mortality in patients with CRAB isolated from sterile sites versus urine, LTCF exposure and severe illness were associated with mortality in both patient groups. CRAB was associated with major mortality in these patients with evidence of healthcare experience and complex illness. More work is needed to determine whether prevention of CRAB infections would improve outcomes.Funding: NoneDisclosures: None


2021 ◽  
Vol 9 (11) ◽  
pp. 183-187
Author(s):  
S.U. Basnayake ◽  
◽  
T.G Dissanayakege ◽  

Although COVID 19 infections in children are generally mild and non-fatal, there is increasing recognition of a multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19, leading to severe illness and long-term sequelae. Even though there is some evidence that the MIS-C is a post-viral immunological reaction to COVID-19, understanding of the immune response induced by SARS-CoV-2 remains unclear.Various local and international guidelines are being widely practiced in the diagnosis and management of patients with MIS-C. A case report of a young child who was diagnosed and managed as MIS-C is discussed here. The diagnostic challenges with the available case definitions and currently accepted treatment options are elaborated herein.


2000 ◽  
Vol 11 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Olaf Weber ◽  
Jürgen Reefschläger ◽  
Helga Rübsamen-Waigmann ◽  
Siegfried Raddatz ◽  
Matthias Hesseling ◽  
...  

Novel peptide aldehydes (PAs) were identified as potent inhibitors of human cytomegalovirus (HCMV) in vitro. Although these compounds were highly effective against HCMV, they did not exhibit any activity against murine cytomegalovirus (MCMV). The purpose of this study was to test the antiviral activity of PA 8 as a representative of this novel class of inhibitors against HCMV in vivo. Because of the strict species specificity of HCMV we had to use two artificial animal models. In the first model, HCMV-infected human cells were entrapped into agarose plugs and transplanted into mice. In the second model, SCID mice were transplanted with human tissues that were subsequently infected with a clinical isolate of HCMV. In these two models the antiviral activity of PA 8 was clearly demonstrated, ganciclovir only being slightly superior in its in vivo antiviral activity.


2018 ◽  
Vol 157 ◽  
pp. 128-133 ◽  
Author(s):  
Sunwen Chou ◽  
Ronald J. Ercolani ◽  
Katayoun Derakhchan

2021 ◽  
Vol 39 (3_suppl) ◽  
pp. TPS253-TPS253
Author(s):  
Farshid Dayyani ◽  
Chloe Thomas ◽  
Gwendolyn Ung ◽  
Thomas H Taylor

TPS253 Background: GEC is the third leading cause of cancer mortality and the fifth most common malignancy worldwide. Fluoropyrimidine and platinum-based combinations are the most commonly used 1L treatment regimens. There are few standard treatment options after 1st line regimens. In the 3L+ GEC Keynote-059 trial, objective response rate (ORR) with Pembro was 15.5% in PD-L1(+) vs. 6.4% in PD-L1(-) tumors. While the responses were durable, the 6-months PFS (6-PFS) was only 14.1% and the median PFS was 2.0 mo. This highlights the remaining unmet need for the majority of patients who either are refractory or develop disease progression following treatment with PD-1 inhibitors in GEC. Cabo plus checkpoint inhibitors have shown clinical benefit in various cancers including hepatocellular, renal cell (RCC), urothelial and castration-resistant prostate cancers. In the CheckMate-9ER trial, Cabo+Nivolumab improved both OS and PFS vs sunitinib in 1L RCC. In patients with RCC who had progression on anti-PD1 inhibitor treatment, Cabo showed promising activity with an ORR of 33% and DCR of 79% (ESMO 2018, abstract 3793). Hypothesis: Based on preclinical and clinical observations, Cabo might contribute to overcoming primary or secondary resistance to PD-1 blockade in GEC. Methods: Prospective, open label, non-randomized phase 2 trial. Eligibility: Diagnosis of GEC, 2+ line of treatment including previous fluoropyrimidine/platinum, ECOG 0-2, adequate organ function, prior checkpoint inhibitor if tumor PD-L1 CPS≥10%. Treatment: Cabozantinib 40mg PO daily, Pembrolizumab 200 mg IV on day 1 of 21d cycle. Primary objective: Feasibility of the combination and estimate of efficacy. Primary endpoint:PFS-6. Secondary objectives: OS, ORR, adverse events. Total number of patients to be enrolled N = 27. Current enrollment (Sep 2020) N = 10. Statistics: If the PFS-6 is > 25%, the study would be regarded as positive, in which case it is planned to expand patient enrollment into a larger single arm phase 2 trial with additional sites to establish the efficacy of the regimen. Clinical trial information: NCT04164979.


2020 ◽  
Vol 123 (6) ◽  
pp. 885-897
Author(s):  
Mark R. Middleton ◽  
Christoph Hoeller ◽  
Olivier Michielin ◽  
Caroline Robert ◽  
Caroline Caramella ◽  
...  

Abstract The emergence of human intratumoural immunotherapy (HIT-IT) is a major step forward in the management of unresectable melanoma. The direct injection of treatments into melanoma lesions can cause cell lysis and induce a local immune response, and might be associated with a systemic immune response. Directly injecting immunotherapies into tumours achieves a high local concentration of immunostimulatory agent while minimising systemic exposure and, as such, HIT-IT agents are associated with lower toxicity than systemic immune checkpoint inhibitors (CPIs), enabling their potential use in combination with other therapies. Consequently, multiple HIT-IT agents, including oncolytic viruses, pattern-recognition receptor agonists, injected CPIs, cytokines and immune glycolipids, are under investigation. This review considers the current clinical development status of HIT-IT agents as monotherapy and in combination with systemic CPIs, and the practical aspects of administering and assessing the response to these agents. The future of HIT-IT probably lies in its use in combination with systemic CPIs; data from Phase 2 trials indicate a synergy between HIT-IT and CPIs. Data also suggest that the addition of HIT-IT to a CPI might generate responses in CPI-refractory tumours, thereby overcoming resistance and addressing a current unmet need in unresectable and metastatic melanoma for treatment options following progression after CPI treatment.


Cancers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1864 ◽  
Author(s):  
Holly Tovey ◽  
Maggie Chon U. Cheang

The concept of precision medicine has been around for many years and recent advances in high-throughput sequencing techniques are enabling this to become reality. Within the field of breast cancer, a number of signatures have been developed to molecularly sub-classify tumours. Notable examples recently approved by National Institute for Health and Care Excellence in the UK to guide treatment decisions for oestrogen receptors (ER)+ human epidermal growth factor receptor 2 (HER2)- patients include Prosigna® test, EndoPredict®, and Oncotype DX®. However, a population of still unmet need are those with triple negative breast cancer (TNBC). Accounting for 15–20% of patients, this population has comparatively poor prognosis and as yet no targeted treatment options. Studies have shown that some patients with TNBC respond favourably to DNA damaging drugs (carboplatin) or agents which inhibit DNA damage response (poly ADP ribose polymerase (PARP) inhibitors). Known to be a heterogeneous population, there is a need to identify further TNBC patients who may benefit from these treatments. A number of signatures have been identified based on association with treatment response or specific genetic features/pathways however many of these were not restricted to TNBC patients and as of yet are not common practice in the clinic.


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