Adjuvant Interactions with Lipid Membranes and Their Effect on Cellular Immune Responses

Adjuvants are commonly included in vaccines and have been invaluable in making them safer and more robust. Despite their prolific use, adjuvant mechanisms of action remain poorly understood. Many receptor-mediated mechanisms have been proposed for adjuvants, and many likely contribute to their mechanisms of action, but several adjuvants also interact with the plasma membrane. Although few have considered how lipid-mediated interactions contribute to adjuvanticity, previous studies suggested aluminum-based adjuvants (ABAs) have high affinity for sphingomyelin and cholesterol, which allowed them to activate dendritic cells exclusively through lipid sorting. This dissertation sought to understand how lipid interactions contribute to the immunostimulatory properties of adjuvants. The membrane interaction of Alhydrogel (AH) and Adju-Phos (AP) was initially investigated in a simple lipid monolayer representative of the outer leaflet of the plasma membrane. AH and AP interacted with the model monolayer and promoted lipid clustering, although the physiochemical properties of each adjuvant caused them to interact differently. In a more complex lipid system containing sphingomyelin and cholesterol, the lipid interaction behavior was consistent and revealed AH and AP stabilized sphingomyelin- and cholesterol-rich lipid domains even in the presence of an antigen. Lipid raft clustering observed in dendritic cells exposed to ABAs in vitro was reminiscent of domain clustering observed in the monolayer and corresponded to conditions which enhanced cell activation, suggesting membrane interactions and lipid sorting could indeed contribute to ABA mechanisms of action. Lipid-interactions were also considered while designing an adjuvant-based antigen-specific immunotherapy (ASIT). An MF59-analog (MF59a) made in our lab was selected to co-deliver ovalbumin and dexamethasone based on its ability to solubilize dexamethasone, extend its release, and enhance its membrane permeability and internalization. The combination of MF59a, ovalbumin, and dexamethasone inhibited several pro-inflammatory cytokines in dendritic cells and ovalbumin-educated splenocytes, and proved emulsion adjuvants could provide an ideal vehicle to create targeted, tolerizing ASITs. Therefore, lipid interactions can provide valuable insight while selecting the physiochemical properties of an adjuvant for pro- and anti-inflammatory applications. Our results provide compelling evidence that lipid interactions participate in adjuvant mechanisms of action, and should be considered when developing novel vaccines and adjuvants

Peak shaving through closed-loop optimization applied to machine tools with periodic behaviour

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This paper deals with machine tools characterized by a periodic behaviour and high-power peaks that require an oversized electrical network and cause high costs because electrical utilities charge greatly each power peak.To solve this issue, a new peak-shaving methodology is proposed based on polynomial models and optimization, to reduce the power-consumption peaks height in machine tools with periodic behaviour. A test-bench that emulates the electrical behaviour of a machine tool is used in order to test the proposed method with real data. In the scenarios simulated, the peak height has been reduced between 35% and 15%.Peer ReviewedPostprint (author's final draft

Preformulation Characterization and Stability Assessments of Secretory IgA Monoclonal Antibodies as Potential Candidates for Passive Immunization by Oral Administration

Enterotoxigenic Escherichia coli (ETEC) is a major cause of diarrheal disease in children in developing countries, and there are no licensed vaccines to protect against ETEC. Passive immunization by oral delivery of ETEC-specific secretory IgAs (sIgAs) could potentially provide an alternative approach for protection in targeted populations. In this study, a series of physiochemical techniques and an in vitro gastric digestion model were used to characterize and compare key structural attributes and stability profiles of three anti-heat labile enterotoxin monoclonal antibodies (sIgA1, sIgA2 and IgG1 produced in CHO cells). The mAbs were evaluated in terms of primary structure, N-linked glycan profiles, size and aggregate content, relative apparent solubility, conformational stability, and in vitro antigen binding. Compared to IgG1 mAb, sIgA1 and sIgA2 mAbs showed increased sample heterogeneity, especially in terms of N-glycan composition and the presence of higher molecular weight species. The sIgA mAbs showed overall better physical stability and were more resistant to loss of antigen binding activity during incubation at low pH, 37 degrees C with pepsin. These results are discussed in terms of future challenges to design stable, low-cost formulations of sIgA mAbs as an oral supplement for passive immunization to protect against enteric diseases in the developing world

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Addressing Global Human Resource Management Challenges Faced by U.S.-Based Business Process Outsourcing Companies Nearshoring to Honduras

When human resource management is conducted in an international setting, HR\u27s main functions are affected by global talent risks, regional trends, and specific characteristics of each location. HR, as we know it domestically, shifts from the regular strategies to new priorities related to the location. To illustrate this premise, the following paper describes the specific characteristics of Honduras, and in particular of its emerging nearshoring industry. The main findings in the literature review are cross-referenced to HR\u27s main functions. In response to the challenges identified, this paper concludes with the proposal of a multi-dynamic model that involves all key stakeholders in the implementation of strategies to overcome HR challenges and risks faced by U.S. nearshoring companies located in Honduras

Peak shaving through closed-loop optimization applied to machine tools with periodic behaviour

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This paper deals with machine tools characterized by a periodic behaviour and high-power peaks that require an oversized electrical network and cause high costs because electrical utilities charge greatly each power peak.To solve this issue, a new peak-shaving methodology is proposed based on polynomial models and optimization, to reduce the power-consumption peaks height in machine tools with periodic behaviour. A test-bench that emulates the electrical behaviour of a machine tool is used in order to test the proposed method with real data. In the scenarios simulated, the peak height has been reduced between 35% and 15%.Peer Reviewe

Codelivery of antigen and an immune cell adhesion inhibitor is necessary for efficacy of soluble antigen arrays in experimental autoimmune encephalomyelitis

Autoimmune diseases such as multiple sclerosis (MS) are typified by the misrecognition of self-antigen and the clonal expansion of autoreactive T cells. Antigen-specific immunotherapies (antigen-SITs) have long been explored as a means to desensitize patients to offending self-antigen(s) with the potential to retolerize the immune response. Soluble antigen arrays (SAgAs) are composed of hyaluronic acid (HA) cografted with disease-specific autoantigen (proteolipid protein peptide) and an ICAM-1 inhibitor peptide (LABL). SAgAs were designed as an antigen-SIT that codeliver peptides to suppress experimental autoimmune encephalomyelitis (EAE), a murine model of MS. Codelivery of antigen and cell adhesion inhibitor (LABL) conjugated to HA was essential for SAgA treatment of EAE. Individual SAgA components or mixtures thereof reduced proinflammatory cytokines in cultured splenocytes from EAE mice; however, these treatments showed minimal to no in vivo therapeutic effect in EAE mice. Thus, carriers that codeliver antigen and a secondary “context” signal (e.g., LABL) in vivo may be an important design criteria to consider when designing antigen-SIT for autoimmune therapy

Systematic influenza screening in cardiac intensive care units during the influenza season: A prospective study in Spain

Background: Little is known about the incidence of influenza among admissions to the cardiac intensive care unit (C-ICU), accuracy of clinical suspicion, and influenza vaccination uptake. We evaluated the incidence of influenza at C-ICU admission during the influenza season, potential underdiagnosis, and vaccination uptake. Methods: Prospective study at five C-ICUs during the 2017-2020 influenza seasons. A nasopharyngeal swab was collected at admission from patients who consented (n = 788). Testing was with Xpert®XpressFlu/RSV. Results: Influenza was detected in 43 patients (5.5%) (40 FluA; 3 FluB) and clinically suspected in 27 (62.8%). Compared to patients without influenza, patients with influenza more frequently had heart failure (37.2% vs 22.8%, P = 0.031), previous contact with relatives with influenza-like illnesses (23.3% vs 12.5%, P = 0.042), antimicrobial use (67.4% vs 23.2%, P <0.01), and need for mechanical ventilation (25.6% vs 14.5%, P = 0.048). Patients received oseltamivir promptly. We found no differences in mortality (11.6% vs 5.2%, P = 0.076). Patients with influenza more frequently had myocarditis (9.3% vs 0.9%, P <0.01) and pericarditis (7.0% vs 0.8%, P = 0.01). Overall, 43.0% of patients (339/788) were vaccinated (51.9% of those with a clear indication [303/584]). Conclusion: Influenza seems to be a frequently underdiagnosed underlying condition in admissions to the C-ICU. Influenza should be screened for at C-ICU admission during influenza epidemics