Dilhari R. DeAlmeida

Antibody breadth and protective efficacy are increased by vaccination with computationally optimized hemagglutinin but not with polyvalent hemagglutinin-based H5N1 virus-like particle vaccines.

ABSTRACT One of the challenges for developing an H5N1 influenza vaccine is the diversity of antigenically distinct isolates within this subtype. Previously, our group described a novel hemagglutinin (HA) derived from a methodology termed computationally optimized broadly reactive antigen (COBRA). This COBRA HA, when used as an immunogen, elicits a broad antibody response against H5N1 isolates from different clades. In this report, the immune responses elicited by the COBRA HA virus-like particle (VLP) vaccine were compared to responses elicited by a mixture of VLPs expressing representative HA molecules from clade 2.1, 2.2, and 2.3 primary H5N1 isolates (polyvalent). The COBRA HA VLP vaccine elicited higher-titer antibodies to a panel of H5N1 HA proteins than did the other VLPs. Both COBRA and polyvalent vaccines protected vaccinated mice and ferrets from experimental infection with highly lethal H5N1 influenza viruses, but COBRA-vaccinated animals had decreased viral replication, less inflammation in the lungs of mice, and reduced virus recovery in ferret nasal washes. Both vaccines had similar cellular responses postchallenge, indicating that higher-titer serum antibodies likely restrict the duration of viral replication. Furthermore, passively transferred immune serum from the COBRA HA VLP-vaccinated mice protected recipient animals more efficiently than immune serum from polyvalent-vaccinated mice. This is the first report comparing these two vaccine strategies. The single COBRA HA antigen elicited a broader antibody response and reduced morbidity and viral titers more effectively than a polyvalent mixture of primary H5N1 HA antigens.

Adjuvants that stimulate TLR3 or NLPR3 pathways enhance the efficiency of influenza virus-like particle vaccines in aged mice.

There is intense interest in the design and use of vaccine strategies against influenza to enhance protective immune responses in the elderly. To address the need for improved influenza vaccines for the aged, two inflammatory adjuvants, Imject(®) alum (a stimulator of the Nod-like receptor, Nalp3) and poly I:C (a toll-like receptor type 3 ligand), were used during vaccination with novel influenza virus-like particles (VLP). Adult (4 month old) or aged (24 month old) mice were vaccinated with VLPs alone or in combination with adjuvant. VLP-vaccinated adult mice were protected from a lethal influenza virus challenge without the use of either adjuvant. In contrast, only aged mice that were vaccinated with VLPs plus adjuvant survived challenge, whereas ∼33% of the mice vaccinated with VLP only survived challenge. Mice vaccinated with adjuvant only did not survive challenge despite similar levels of activation of CD11b(+)/CD11c(+) dendritic cells in the lungs. The protection was not associated with HAI titers or HA specific CD8(+) T cells, since both adjuvants boosted the VLP-induced serum HAI titers and CD8(+) responses in adult mice, but not aged mice. Influenza VLPs used in combination with two different inflammatory adjuvants during vaccination allow for the immune system to overcome the deficiency in the aged immune system to influenza virus infection.

An agent-based model of inflammation and fibrosis following particulate exposure in the lung

Inflammation and airway remodeling occur in a variety of airway diseases. Modeling aspects of the inflammatory and fibrotic processes following repeated exposure to particulate matter may provide insights into a spectrum of airway diseases, as well as prevention/treatment strategies. An agent-based model (ABM) was created to examine the response of an abstracted population of inflammatory cells (nominally macrophages, but possibly including other inflammatory cells such as lymphocytes) and cells involved in remodeling (nominally fibroblasts) to particulate exposure. The model focused on a limited number of relevant interactions, specifically those among macrophages, fibroblasts, a pro-inflammatory cytokine (TNF-α), an anti-inflammatory cytokine (TGF-β1), collagen deposition, and tissue damage. The model yielded three distinct states that were equated with (1) self-resolving inflammation and a return to baseline, (2) a pro-inflammatory process of localized tissue damage and fibrosis, and (3) elevated pro- and anti-inflammatory cytokines, persistent tissue damage, and fibrosis outcomes. Experimental results consistent with these predicted states were observed in histology sections of lung tissue from mice exposed to particulate matter. Systematic in silico studies suggested that the development of each state depended primarily upon the degree and duration of exposure. Thus, a relatively simple ABM resulted in several, biologically feasible, emergent states, suggesting that the model captures certain salient features of inflammation following exposure of the lung to particulate matter. This ABM may hold future utility in the setting of airway disease resulting from inflammation and fibrosis following particulate exposure.

Elicitation of Anti-1918 Influenza Virus Immunity Early in Life Prevents Morbidity and Lower Levels of Lung Infection by 2009 Pandemic H1N1 Influenza Virus in Aged Mice

ABSTRACT The Spanish influenza virus pandemic of 1918 was responsible for 40 million to 50 million deaths and is antigenically similar to the swine lineage 2009 pandemic influenza virus. Emergence of the 2009 pandemic from swine into humans has raised the possibility that low levels of cross-protective immunity to past shared epitopes could confer protection. In this study, influenza viruslike particles (VLPs) were engineered to express the hemagglutinin (HA) and genes from the 1918 influenza virus to evaluate the duration of cross-protection to the H1N1 pandemic strain by vaccinating young mice (8 to 12 weeks) and then allowing the animals to age to 20 months. This immunity was long lasting, with homologous receptor-blocking antibodies detected throughout the lifespan of vaccinated mice. Furthermore, the 1918 VLPs fully protected aged mice from 2009 pandemic H1N1 virus challenge 16 months after vaccination. Histopathological assessment showed that aged vaccinated mice had significant protection from alveolar infection but less protection of the bronchial tissue than adult vaccinated mice. Additionally, passive transfer of immune serum from aged vaccinated mice resulted in protection from death but not morbidity. This is the first report describing the lifelong duration of cross-reactive immune responses elicited by a 1918 VLP vaccine in a murine model. Importantly, these lifelong immune responses did not result in decreased total viral replication but did prevent infection of the lower respiratory tract. These findings show that immunity acquired early in life can restrict the anatomical location of influenza viral replication, rather than preventing infection, in the aged.

C3d adjuvant activity is reduced by altering residues involved in the electronegative binding of C3d to CR2

The final degradation product of the complement protein C3, C3d, has been used as a molecular adjuvant to various antigens. Chimera proteins of the antigen and multiple copies of C3d were developed to test the adjuvant effect of this molecule. The main mechanism by which C3d enhances the immune response is interaction with CR2. In vitro studies showed that the avidity of C3d for CR2 is affected by residues located at the interacting surface (e.g. 170N) as well as by residues located in other areas. The role of the latter residues has been proposed to depend on the electrostatic nature of the C3d-CR2 interaction, where the charges of the whole molecules are responsible for their binding. C3d is primarily a negatively charged molecule, while CR2 is a positive one. Previous experiments demonstrated that elimination of a positive charge (K162A) in C3d enhanced its avidity for CR2, while elimination of negative charges or addition positives ones (D163A, N170R, respectively), impaired the avidity for CR2. Despite the extensive in vitro research, the role of these residues in the adjuvant effect of C3d is unclear. To study the role of residues at the interacting and non-interacting surface of C3d on the adjuvanticity, single as well as a double residue substitutions were engineered in the murine C3d (R162A, D163A, N170R and D163A-N170R) gene. Two copies of these mutant molecules were fused to HIV-1 Env(gp120) and the proteins were tested for their avidity to bind CR2 (sCR2). Later, these DNA constructs were tested in mice to determine their adjuvant capability. Mutation at residue 162 (R162A) neither enhanced nor impaired the avidity of Env(gp120)-C3d(2) for sCR2 in vitro. Mutations at residues D163A and N170R, on the other hand, reduced the binding affinity of Env(gp120)-C3d(2) for sCR2. Furthermore, these mutations synergized and abolished the interaction of C3d for CR2. The data correlated with the adjuvant capability of these molecules in the mouse model. In summary, residues that alter the electronegative status of C3d (D163A and N170R) impair the binding of chimera proteins to CR2, reducing the adjuvant activity of this molecule.

Clinical Decision Support for In-Hospital AKI

AKI carries a significant mortality and morbidity risk. Use of a clinical decision support system (CDSS) might improve outcomes. We conducted a multicenter, sequential period analysis of 528,108 patients without ESRD before admission, from October of 2012 to September of 2015, to determine whether use of a CDSS reduces hospital length of stay and in-hospital mortality for patients with AKI. We compared patients treated 12 months before (181,696) and 24 months after (346,412) implementation of the CDSS. Coprimary outcomes were hospital mortality and length of stay adjusted by demographics and comorbidities. AKI was diagnosed in 64,512 patients (12.2%). Crude mortality rate fell from 10.2% before to 9.4% after CDSS implementation (odds ratio, 0.91; 95% confidence interval [95% CI], 0.86 to 0.96; P=0.001) for patients with AKI but did not change in patients without AKI (from 1.5% to 1.4%). Mean hospital duration decreased from 9.3 to 9.0 days (P<0.001) for patients with AKI, with no change for patients without AKI. In multivariate mixed-effects models, the adjusted odds ratio (95% CI) was 0.76 (0.70 to 0.83) for mortality and 0.66 (0.61 to 0.72) for dialysis (P<0.001). Change in adjusted hospital length of stay was also significant (incidence rate ratio, 0.91; 95% CI, 0.89 to 0.92), decreasing from 7.2 to 6.0 days for patients with AKI. Results were robust to sensitivity analyses and were sustained for the duration of follow-up. Hence, implementation of a CDSS for AKI resulted in a small but sustained decrease in hospital mortality, dialysis use, and length of stay.

Use of an Electronic Medical Record (EMR) to Identify Glycemic Intensification Strategies in Type 2 Diabetes

Background: Current treatment guidelines for type 2 diabetes (T2D) recommend individualized intensification of therapy for glycated hemoglobin (A1C) ≥ 7% in most patients. The purpose of this investigation was to explore the ability of an electronic medical record (EMR) to identify glycemic intensification strategies among T2D patients receiving pharmacologic therapy. Methods: Patient records between 2005 and 2011 with documentation of A1C and active prescriptions for any diabetes medications were queried to identify potential candidates for intensification based on A1C ≥ 7% while on 1-2 oral diabetes medications (ODM). Patients with follow-up A1C values within 1 year of index A1C were grouped according to intensification with insulin, GLP-1 receptor agonists (GLP-1RA), a new class of ODM, or no intensification. Changes in A1C and continuation of intensification therapy were determined. Results: A total of 4921 patients meeting inclusion criteria were intensified with insulin (n = 416), GLP-1RA (n = 68), ODM (n = 1408), or no additional therapy (n = 3029). Patients receiving insulin had higher baseline (9.3 ± 2.0 vs 8.3 ± 1.2 vs 8.3 ± 1.3 vs 7.6 ± 1.0%, P < .0001) and follow-up A1C (8.1 ± 1.6 vs 7.5 ± 1.2 vs 7.6 ± 1.3 vs 7.2 ± 1.1%, P < .0001) despite experiencing larger absolute A1C reductions (−1.2 ± 2.1 vs −0.8 ± 1.4 vs −0.7 ± 1.4 vs −0.3 ± 1.1%, P < .0001). Patients receiving GLP-1RA were more obese at baseline (BMI: 33.6 ± 7.1 vs 37.7 ± 6.1 vs 33.7 ± 6.8 vs 32.9 ± 7.1 kg/m2, P < .0001) and follow-up (BMI: 33.9 ± 7.3 vs 36.6 ± 6.1 vs 33.8 ± 7.0 vs 32.4 ± 7.0 kg/m2, P < .0001) despite experiencing more absolute weight reduction. Insulin was the most and GLP-1RA the least likely therapy to be continued. Conclusions: An EMR allows identification of prescribing practices and compliance with T2D treatment guidelines. Patients receiving intensification of glycemic medications had baseline A1C >8% suggesting that treatment recommendations are not being followed.

Protocol for Systematic Review in Privacy and Security in Telehealth: Best Practices for Healthcare Professionals

Healthcare professionals engaged in telehealth are faced with complex US federal regulations (e.g., HIPAA/HITECH) and could benefit from the guidance provided by best practices in Privacy and Security (P&S). This article describes a systematic review protocol to address this need. The protocol described herein uses the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). The PRISMA-P contains 17 items that are considered essential, as well as minimum components to include in systematic reviews. PICOS (participants, interventions, comparisons, outcome(s) and study design of the systematic review) are also relevant to the development of best practices in P&S in telehealth systems. A systematic process can best determine what information should be included and how this information should be retrieved, condensed, analyzed, organized, and disseminated.

eResearch in acute kidney injury: a primer for electronic health record research

Acute kidney injury (AKI) has a significant impact on patient morbidity and mortality as well as overall health care costs. eResearch, which integrates information technology and information management to optimize research strategies, provides a perfect platform for necessary ongoing AKI research. With the recent adoption of a widely accepted definition of AKI and near-universal use of electronic health records, eResearch is becoming an important tool in AKI research. Conducting eResearch in AKI should ideally be based on a relatively uniform methodology. This article is the first of its kind to describe a methodology for pursuing eResearch specific to AKI and includes an illustrative database example for critically ill patients. We discuss strategies for using serum creatinine and urine output in large databases to identify and stage AKI and ways to interpolate missing values and validate data. Issues specific to the pediatric population include variation in serum creatinine with growth, varied severity of illness scoring systems and medication dosage based on weight. Many of these same strategies used to optimize AKI eResearch can be applicable to real-time AKI alerts with potential integration of additional clinical variables.

A Systematic Review of Research Studies Examining Telehealth Privacy and Security Practices Used By Healthcare Providers

The objective of this systematic review was to systematically review papers in the United States that examine current practices in privacy and security when telehealth technologies are used by healthcare providers. A literature search was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P). PubMed, CINAHL and INSPEC from 2003 – 2016 were searched and returned 25,404 papers (after duplications were removed). Inclusion and exclusion criteria were strictly followed to examine title, abstract, and full text for 21 published papers which reported on privacy and security practices used by healthcare providers using telehealth. Data on confidentiality, integrity, privacy, informed consent, access control, availability, retention, encryption, and authentication were all searched and retrieved from the papers examined. Papers were selected by two independent reviewers, first per inclusion/exclusion criteria and, where there was disagreement, a third reviewer was consulted. The percentage of agreement and Cohen’s kappa was 99.04% and 0.7331 respectively. The papers reviewed ranged from 2004 to 2016 and included several types of telehealth specialties. Sixty-seven percent were policy type studies, and 14 percent were survey/interview studies. There were no randomized controlled trials. Based upon the results, we conclude that it is necessary to have more studies with specific information about the use of privacy and security practices when using telehealth technologies as well as studies that examine patient and provider preferences on how data is kept private and secure during and after telehealth sessions.