A novel CSP C-terminal epitope targeted by an antibody with protective activity against Plasmodium falciparum.

Potent and durable vaccine responses will be required for control of malaria caused by Plasmodium falciparum (Pf). RTS,S/AS01 is the first, and to date, the only vaccine that has demonstrated significant reduction of clinical and severe malaria in endemic cohorts in Phase 3 trials. Although the vaccine is protective, efficacy declines over time with kinetics paralleling the decline in antibody responses to the Pf circumsporozoite protein (PfCSP). Although most attention has focused on antibodies to repeat motifs on PfCSP, antibodies to other regions may play a role in protection. Here, we expressed and characterized seven monoclonal antibodies to the C-terminal domain of CSP (ctCSP) from volunteers immunized with RTS,S/AS01. Competition and crystal structure studies indicated that the antibodies target two different sites on opposite faces of ctCSP. One site contains a polymorphic region (denoted α-ctCSP) and has been previously characterized, whereas the second is a previously undescribed site on the conserved ß-sheet face of the ctCSP (denoted ß-ctCSP). Antibodies to the ß-ctCSP site exhibited broad reactivity with a diverse panel of ctCSP peptides whose sequences were derived from field isolates of P. falciparum whereas antibodies to the α-ctCSP site showed very limited cross reactivity. Importantly, an antibody to the ß-site demonstrated inhibition activity against malaria infection in a murine model. This study identifies a previously unidentified conserved epitope on CSP that could be targeted by prophylactic antibodies and exploited in structure-based vaccine design.

Clinicians' use of Health Information Exchange technologies for medication reconciliation in the U.S. Department of Veterans Affairs: a qualitative analysis.

BACKGROUND: Medication reconciliation is essential for optimizing medication use. In part to promote effective medication reconciliation, the Department of Veterans Affairs (VA) invested substantial resources in health information exchange (HIE) technologies. The objectives of this qualitative study were to characterize VA clinicians' use of HIE tools for medication reconciliation in their clinical practice and to identify facilitators and barriers. METHODS: We recruited inpatient and outpatient prescribers (physicians, nurse practitioners, physician assistants) and pharmacists at four geographically distinct VA medical centers for observations and interviews. Participants were observed as they interacted with HIE or medication reconciliation tools during routine work. Participants were interviewed about clinical decision-making pertaining to medication reconciliation and use of HIE tools, and about barriers and facilitators to use of the tools. Qualitative data were analyzed via inductive and deductive approaches using a priori codes. RESULTS: A total of 63 clinicians participated. Over half (58%) were female, and the mean duration of VA clinical experience was 7 (range 0-32) years. Underlying motivators for clinicians seeking data external to their VA medical center were having new patients, current patients receiving care from an external institution, and clinicians' concerns about possible medication discrepancies among institutions. Facilitators for using HIE software were clinicians' familiarity with the HIE software, clinicians' belief that medication information would be available within HIE, and their confidence in the ability to find HIE medication-related data of interest quickly. Six overarching barriers to HIE software use for medication coordination included visual clutter and information overload within the HIE display; challenges with HIE interface navigation; lack of integration between HIE and other electronic health record interfaces, necessitating multiple logins and application switching; concerns with the dependability of HIE medication information; unfamiliarity with HIE tools; and a lack of HIE data from non-VA facilities. CONCLUSIONS: This study is believed to be the first to qualitatively characterize clinicians' HIE use with respect to medication reconciliation. Results inform recommendations to optimize HIE use for medication management activities. We expect that healthcare organizations and software vendors will be able to apply the findings to develop more effective and usable HIE information displays.

A Community-Informed Maternal and Infant Health Needs Assessment in Alabama.

BACKGROUND: Maternal mortality is a global clinical and public health crisis. Researchers and leading organizations have highlighted the need for local partnerships to implement evidence-based strategies to mitigate poor outcomes. Alabama has the third highest maternal mortality rate in the nation. Research on the complexity of maternity mortality is strengthening, but poor outcomes in Alabama persist and there is limited data highlighting the perspectives of those on the frontlines of providing and receiving care. PURPOSE: We conducted a qualitative, statewide, community-informed, maternal and infant health research assessment with physicians, providers, professionals, and birthing persons to identify challenges and solutions to addressing the states' poor perinatal health outcomes.   METHODS: Data were collected using a four-phase, research design that included semi-structured interviews, focus groups, one state-wide data sharing event, and five regional data sharing events. Data were collected between January 2020 and October 2021. The data were analyzed using consensus coding and thematic analysis. MAIN FINDINGS: Fifty-nine (N = 59) individuals participated. Three themes emerged: 1) "They were making me feel so overlooked.": A disconnect between perinatal healthcare services and patient needs; 2) "That shouldn't be something you have to ask for.": Limitations to providing respectful perinatal healthcare; and 3) "If they work together, they can have all the tools they need.": Building a case for collaborative care. CONCLUSIONS: Participants advocated for a collaborative perinatal healthcare model that focuses on the provision of respectful, quality perinatal healthcare. Our approach can be applied across contexts and used to support the effective implementation of contextually relevant maternity care practices.

Detecting Psychological Interventions Using Bilateral Electromyographic Wearable Sensors.

This study investigated the impact of auditory stimuli on muscular activation patterns using wearable surface electromyography (EMG) sensors. Employing four key muscles (Sternocleidomastoid Muscle (SCM), Cervical Erector Muscle (CEM), Quadricep Muscles (QMs), and Tibialis Muscle (TM)) and time domain features, we differentiated the effects of four interventions: silence, music, positive reinforcement, and negative reinforcement. The results demonstrated distinct muscle responses to the interventions, with the SCM and CEM being the most sensitive to changes and the TM being the most active and stimulus dependent. Post hoc analyses revealed significant intervention-specific activations in the CEM and TM for specific time points and intervention pairs, suggesting dynamic modulation and time-dependent integration. Multi-feature analysis identified both statistical and Hjorth features as potent discriminators, reflecting diverse adaptations in muscle recruitment, activation intensity, control, and signal dynamics. These features hold promise as potential biomarkers for monitoring muscle function in various clinical and research applications. Finally, muscle-specific Random Forest classification achieved the highest accuracy and Area Under the ROC Curve for the TM, indicating its potential for differentiating interventions with high precision. This study paves the way for personalized neuroadaptive interventions in rehabilitation, sports science, ergonomics, and healthcare by exploiting the diverse and dynamic landscape of muscle responses to auditory stimuli.

Assessing Doula Preparedness for Supporting Clients in a Hospital-Based Volunteer Doula Program.

PURPOSE AND BACKGROUND: The purpose of this evaluation was to assess doulas' sense of preparedness after completing birth doula training. The extent to which doulas feel prepared to serve clients after training is unknown. METHODS: This program evaluation took place within a hospital-based volunteer doula program in the southeastern United States. The analysis focused on comparing the self-reported preparedness of volunteer doulas trained through the Partners in Birth Training program, a doula training created by the doula program, with preparedness of volunteer doulas trained by nationally recognized training programs. A survey assessed doulas' preparedness to provide physical, emotional, and informational support. RESULTS: Of the 100 doulas active in the program at the time of survey administration, 48 had completed the Partners in Birth Training program, 26 (54%) of whom completed the survey. Of the 32 doulas who entered the doula program following training with national organizations, 19 (59%) completed the survey. The remaining 20 doulas in the program completed a third training option and were excluded from this evaluation. In comparing doulas' overall sense of preparedness between the 2 groups, results were similar, with the median response for both groups being mostly prepared (4 on a Likert scale from 1 to 5). CONCLUSIONS: Results suggest that localized doula training offered by hospital-based doula programs may be as effective at preparing doulas to serve in such programs as Other training organizations. IMPLICATIONS FOR PRACTICE AND RESEARCH: Systematic evaluations can help researchers and doulas identify topics and pedagogical approaches to training that increase preparedness.

COVID-19 Vaccination Effectiveness Against Infection or Death in a National U.S. Health Care System : A Target Trial Emulation Study.

BACKGROUND: Little is known about real-world COVID-19 vaccine effectiveness (VE) in racially and ethnically diverse, elderly populations with high comorbidity burden. OBJECTIVE: To determine the effectiveness of messenger RNA COVID-19 vaccines. DESIGN: Target trial emulation study comparing newly vaccinated persons with matched unvaccinated controls. SETTING: U.S. Department of Veterans Affairs health care system. PARTICIPANTS: Among persons receiving care in the Veterans Affairs health care system (n = 5 766 638), those who received at least 1 dose of the Moderna or Pfizer-BioNTech COVID-19 vaccine from 11 December 2020 to 25 March 2021 (n = 2 099 871) were matched to unvaccinated controls in a 1:1 ratio according to demographic, clinical, and geographic characteristics. INTERVENTION: Follow-up for SARS-CoV-2 infection or SARS-CoV-2-related death, defined as death within 30 days of infection, began after the vaccination date or an identical index date for the matched unvaccinated controls and continued until up to 30 June 2021. MEASUREMENTS: Vaccine effectiveness against SARS-CoV-2 infection or SARS-CoV-2-related death. RESULTS: Vaccinated and unvaccinated groups were well matched; both were predominantly male (92.9% vs. 93.4%), had advanced age (mean, 68.7 years in both groups), had diverse racial and ethnic distribution (for example, Black: 17.3% vs. 17.0%, Hispanic: 6.5% vs. 6.1%), and had substantial comorbidity burden. Vaccine effectiveness 7 or more days after the second vaccine dose was 69% (95% CI, 67% to 70%) against SARS-CoV-2 infection and 86% (CI, 82% to 89%) against SARS-CoV-2-related death and was similar when follow-up was extended to 31 March versus 30 June. Vaccine effectiveness against infection decreased with increasing age and comorbidity burden. LIMITATION: Predominantly male population and lack of data on SARS-CoV-2 variants. CONCLUSION: In an elderly, diverse, high-comorbidity population, COVID-19 VE against infection was substantially lower than previously reported, but VE against death was high. Complementary infection mitigation efforts remain important for pandemic control, even with vaccination. PRIMARY FUNDING SOURCE: U.S. Department of Veterans Affairs.

Trends Over Time in the Risk of Adverse Outcomes Among Patients With Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

BACKGROUND: We aimed to describe trends in adverse outcomes among patients who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) between February and September 2020 within a national healthcare system. METHODS: We identified enrollees in the national United States Veterans Affairs healthcare system who tested positive for SARS-CoV-2 between 28 February 2020 and 30 September 2020 (n = 55 952), with follow-up extending to 19 November 2020. We determined trends over time in incidence of the following outcomes that occurred within 30 days of testing positive: hospitalization, intensive care unit (ICU) admission, mechanical ventilation, and death. RESULTS: Between February and July 2020, there were marked downward trends in the 30-day incidence of hospitalization (44.2% to 15.8%), ICU admission (20.3% to 5.3%), mechanical ventilation (12.7% to 2.2%), and death (12.5% to 4.4%), which subsequently plateaued between July and September 2020. These trends persisted after adjustment for sociodemographic characteristics, comorbid conditions, documented symptoms, and laboratory tests, including among subgroups of patients hospitalized, admitted to the ICU, or treated with mechanical ventilation. From February to September, there were decreases in the use of hydroxychloroquine (56.5% to 0%), azithromycin (48.3% to 16.6%), vasopressors (20.6% to 8.7%), and dialysis (11.6% to 3.8%) and increases in the use of dexamethasone (3.4% to 53.1%), other corticosteroids (4.9% to 29.0%), and remdesivir (1.7% to 45.4%) among hospitalized patients. CONCLUSIONS: The risk of adverse outcomes in SARS-CoV-2-positive patients decreased markedly between February and July, with subsequent stabilization from July to September. These trends were not explained by changes in measured baseline patient characteristics and may reflect changing treatment practices or viral pathogenicity.

Structure and mechanism of monoclonal antibody binding to the junctional epitope of Plasmodium falciparum circumsporozoite protein.

Lasting protection has long been a goal for malaria vaccines. The major surface antigen on Plasmodium falciparum sporozoites, the circumsporozoite protein (PfCSP), has been an attractive target for vaccine development and most protective antibodies studied to date interact with the central NANP repeat region of PfCSP. However, it remains unclear what structural and functional characteristics correlate with better protection by one antibody over another. Binding to the junctional region between the N-terminal domain and central NANP repeats has been proposed to result in superior protection: this region initiates with the only NPDP sequence followed immediately by NANP. Here, we isolated antibodies in Kymab mice immunized with full-length recombinant PfCSP and two protective antibodies were selected for further study with reactivity against the junctional region. X-ray and EM structures of two monoclonal antibodies, mAb667 and mAb668, shed light on their differential affinity and specificity for the junctional region. Importantly, these antibodies also bind to the NANP repeat region with equal or better affinity. A comparison with an NANP-only binding antibody (mAb317) revealed roughly similar but statistically distinct levels of protection against sporozoite challenge in mouse liver burden models, suggesting that junctional antibody protection might relate to the ability to also cross-react with the NANP repeat region. Our findings indicate that additional efforts are necessary to isolate a true junctional antibody with no or much reduced affinity to the NANP region to elucidate the role of the junctional epitope in protection.

Cirrhosis and Severe Acute Respiratory Syndrome Coronavirus 2 Infection in US Veterans: Risk of Infection, Hospitalization, Ventilation, and Mortality.

BACKGROUND AND AIMS: Whether patients with cirrhosis have increased risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the extent to which infection and cirrhosis increase the risk of adverse patient outcomes remain unclear. APPROACH AND RESULTS: We identified 88,747 patients tested for SARS-CoV-2 between March 1, 2020, and May 14, 2020, in the Veterans Affairs (VA) national health care system, including 75,315 with no cirrhosis-SARS-CoV-2-negative (C0-S0), 9,826 with no cirrhosis-SARS-CoV-2-positive (C0-S1), 3,301 with cirrhosis-SARS-CoV-2-negative (C1-S0), and 305 with cirrhosis-SARS-CoV-2-positive (C1-S1). Patients were followed through June 22, 2020. Hospitalization, mechanical ventilation, and death were modeled in time-to-event analyses using Cox proportional hazards regression. Patients with cirrhosis were less likely to test positive than patients without cirrhosis (8.5% vs. 11.5%; adjusted odds ratio, 0.83; 95% CI, 0.69-0.99). Thirty-day mortality and ventilation rates increased progressively from C0-S0 (2.3% and 1.6%) to C1-S0 (5.2% and 3.6%) to C0-S1 (10.6% and 6.5%) and to C1-S1 (17.1% and 13.0%). Among patients with cirrhosis, those who tested positive for SARS-CoV-2 were 4.1 times more likely to undergo mechanical ventilation (adjusted hazard ratio [aHR], 4.12; 95% CI, 2.79-6.10) and 3.5 times more likely to die (aHR, 3.54; 95% CI, 2.55-4.90) than those who tested negative. Among patients with SARS-CoV-2 infection, those with cirrhosis were more likely to be hospitalized (aHR, 1.37; 95% CI, 1.12-1.66), undergo ventilation (aHR, 1.61; 95% CI, 1.05-2.46) or die (aHR, 1.65; 95% CI, 1.18-2.30) than patients without cirrhosis. Among patients with cirrhosis and SARS-CoV-2 infection, the most important predictors of mortality were advanced age, cirrhosis decompensation, and high Model for End-Stage Liver Disease score. CONCLUSIONS: SARS-CoV-2 infection was associated with a 3.5-fold increase in mortality in patients with cirrhosis. Cirrhosis was associated with a 1.7-fold increase in mortality in patients with SARS-CoV-2 infection.

Caregiver Experiences and Roles in Care Seeking During COPD Exacerbations: A Qualitative Study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a progressive, debilitating illness characterized by exacerbations that require timely intervention. COPD patients often rely on informal caregivers-relatives or friends-for assistance with functioning and support. Caregivers perform roles that may be particularly important during acute exacerbations in monitoring symptoms and seeking medical intervention. However, little is known about caregivers' roles and experiences as they support their patients during exacerbations. PURPOSE: To explore the experiences, roles in care seeking, and needs of caregivers during COPD exacerbations. METHODS: Semi-structured interviews were conducted with 24 caregivers of Veterans with COPD who experienced a recent exacerbation. Interviews were recorded, transcribed, and analyzed using inductive content analysis. RESULTS: Five themes arose: (a) caregivers reported continuously monitoring changes in patients symptom severity to identify exacerbations; (b) caregivers described emotional reactions evoked by exacerbations and constant vigilance; (c) caregivers described disagreements with their patient in interpreting symptoms and determining the need for care seeking; (d) caregivers noted uncertainty regarding their roles and responsibilities in pursuing care and their approaches to promote care varied; and (e) expressed their need for additional information and support. Caregivers of patients with COPD often influence whether and when patients seek care during exacerbations. Discrepancies in symptom evaluations between patients and caregivers paired with the lack of information and support available to caregivers are related to delays in care seeking. Clinical practice should foster self-management support to patient-caregiver dyads to increase caregiver confidence and patient openness to their input during exacerbations.

Potential Explanatory Factors for the Concurrent Experience of Dyspnea and Pain in Patients with COPD.

Previous research has identified unexpectedly strong associations between dyspnea and pain, but the reasons remain unclear. Ascertaining the underlying biological and psychological mechanisms might enhance the understanding of the experience of both conditions, and suggest novel treatments. We sought to elucidate whether demographic factors, disease severity, psychological symptoms and biomarkers might account for the association between pain and dyspnea in individuals with COPD. We analyzed data from 301 patients with COPD who were followed in a prospective longitudinal observational study over 2 years. Measures included self-reported dyspnea and pain, pulmonary function tests, serum levels of inflammatory cytokines, measures of physical deconditioning, and scales for depression and anxiety. Analyses involved cross-sectional and longitudinal linear regression models. Pain and dyspnea were strongly correlated cross-sectionally (r = 0.77, 95% CI 0.72-0.82) and simultaneously across time (r = 0.42, 95% CI 0.28-0.56). Accounting for any of the other health factors only slightly mitigated the associations. Symptoms of pain and dyspnea thus may be fundamentally linked in COPD, rather than being mediated by common biological, psychological, or functional factors. From the patient's perspective, pain and dyspnea may be part of the same essential experience. It is possible that treatments for one condition would improve the other.

Identifying Individuals Who Currently Report Feelings of Anxiety Using Walking Gait and Quiet Balance: An Exploratory Study Using Machine Learning.

Literature suggests that anxiety affects gait and balance among young adults. However, previous studies using machine learning (ML) have only used gait to identify individuals who report feeling anxious. Therefore, the purpose of this study was to identify individuals who report feeling anxious at that time using a combination of gait and quiet balance ML. Using a cross-sectional design, participants (n = 88) completed the Profile of Mood Survey-Short Form (POMS-SF) to measure current feelings of anxiety and were then asked to complete a modified Clinical Test for Sensory Interaction in Balance (mCTSIB) and a two-minute walk around a 6 m track while wearing nine APDM mobility sensors. Results from our study finds that Random Forest classifiers had the highest median accuracy rate (75%) and the five top features for identifying anxious individuals were all gait parameters (turn angles, variance in neck, lumbar rotation, lumbar movement in the sagittal plane, and arm movement). Post-hoc analyses suggest that individuals who reported feeling anxious also walked using gait patterns most similar to older individuals who are fearful of falling. Additionally, we find that individuals who are anxious also had less postural stability when they had visual input; however, these individuals had less movement during postural sway when visual input was removed.

The Plasmodium falciparum circumsporozoite protein produced in Lactococcus lactis is pure and stable.

The Plasmodium falciparum circumsporozoite protein (PfCSP) is a sporozoite surface protein whose role in sporozoite motility and cell invasion has made it the leading candidate for a pre-erythrocytic malaria vaccine. However, production of high yields of soluble recombinant PfCSP, including its extensive NANP and NVDP repeats, has proven problematic. Here, we report on the development and characterization of a secreted, soluble, and stable full-length PfCSP (containing 4 NVDP and 38 NANP repeats) produced in the Lactococcus lactis expression system. The recombinant full-length PfCSP, denoted PfCSP4/38, was produced initially with a histidine tag and purified by a simple two-step procedure. Importantly, the recombinant PfCSP4/38 retained a conformational epitope for antibodies as confirmed by both in vivo and in vitro characterizations. We characterized this complex protein by HPLC, light scattering, MS analysis, differential scanning fluorimetry, CD, SDS-PAGE, and immunoblotting with conformation-dependent and -independent mAbs, which confirmed it to be both pure and soluble. Moreover, we found that the recombinant protein is stable at both frozen and elevated-temperature storage conditions. When we used L. lactis-derived PfCSP4/38 to immunize mice, it elicited high levels of functional antibodies that had the capacity to modify sporozoite motility in vitro We concluded that the reported yield, purity, results of biophysical analyses, and stability of PfCSP4/38 warrant further consideration of using the L. lactis system for the production of circumsporozoite proteins for preclinical and clinical applications in malaria vaccine development.

Risk Factors for Testing Positive for Severe Acute Respiratory Syndrome Coronavirus 2 in a National United States Healthcare System.

BACKGROUND: Identifying risk factors for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection could help health systems improve testing and screening strategies. The aim of this study was to identify demographic factors, comorbid conditions, and symptoms independently associated with testing positive for SARS-CoV-2. METHODS: This was an observational cross-sectional study at the Veterans Health Administration, including persons tested for SARS-CoV-2 nucleic acid by polymerase chain reaction (PCR) between 28 February and 14 May 2020. Associations between demographic characteristics, diagnosed comorbid conditions, and documented symptoms with testing positive for SARS-CoV-2 were measured. RESULTS: Of 88 747 persons tested, 10 131 (11.4%) were SARS-CoV-2 PCR positive. Positivity was associated with older age (≥80 vs <50 years: adjusted odds ratio [aOR], 2.16 [95% confidence interval {CI}, 1.97-2.37]), male sex (aOR, 1.45 [95% CI, 1.34-1.57]), regional SARS-CoV-2 burden (≥2000 vs <400 cases/million: aOR, 5.43 [95% CI, 4.97-5.93]), urban residence (aOR, 1.78 [95% CI, 1.70-1.87]), black (aOR, 2.15 [95% CI, 2.05-2.26]) or American Indian/Alaska Native Hawaiian/Pacific Islander (aOR, 1.26 [95% CI, 1.05-1.52]) vs white race, and Hispanic ethnicity (aOR, 1.52 [95% CI, 1.40-1.65]). Obesity and diabetes were the only 2 medical conditions associated with testing positive. Documented fevers, chills, cough, and diarrhea were also associated with testing positive. The population attributable fraction of positive tests was highest for geographic location (35.3%), followed by demographic variables (27.1%), symptoms (12.0%), obesity (10.5%), and diabetes (0.4%). CONCLUSIONS: The majority of positive SARS-CoV-2 tests were attributed to geographic location, demographic characteristics, and obesity, with a minor contribution of chronic comorbid conditions.

Sociodemographic Characteristics and Physical Activity in Patients with COPD: A 3-Month Cohort Study.

Decreased physical activity (PA) is associated with morbidity and mortality in COPD patients. In this secondary analysis of data from a 12-week longitudinal study, we describe factors associated with PA in COPD. Participants completed the Physical Activity Checklist (PAC) daily for a 7- to 8-day period. PA was measured monthly using the Physical Activity Scale for the Elderly (PASE). At three different time points, daily step count was measured for one week with an Omron HJ-720ITC pedometer. The 35 participants were primarily male (94%) and White (91%), with an average age of 66.5 years and FEV1 44.9% predicted. Common activities reported on the PAC were walking (93%), preparing a meal (89%), and traveling by vehicle (96%). PA measured by both PASE score (p = 0.01) and average daily step count (p = 0.04) decreased during follow-up. In repeated measures multivariable modeling, participants living with others had a higher daily step count (ß = 942 steps, p = 0.01) and better PASE scores (ß = 46.4, p < 0.001). Older age was associated with decreased step count (ß = -77 steps, p < 0.001) whereas White race was associated with lower PASE scores (ß = -55.4, p < 0.001) compared to non-White race. Other demographic factors, quality of life, and medications were not associated with PA. A better understanding of the role of social networks and social support may help develop interventions to improve PA in COPD.

Comparison of ELISA with electro-chemiluminescence technology for the qualitative and quantitative assessment of serological responses to vaccination.

BACKGROUND: Profiling immune responses induced by either infection or vaccination can provide insight into identification of correlates of protection. Furthermore, profiling of serological responses can be used to identify biomarkers indicative of exposure to pathogens. Conducting such immune surveillance requires readout methods that are high-throughput, robust, and require small sample volumes. While the enzyme-linked immunosorbent assay (ELISA) is the classical readout method for assessing serological responses, the advent of multiplex assays has significantly increased the throughput and capacity for immunoprofiling. This report describes the development and assay performance (sensitivity, linearity of detection, requirement for multiple dilutions for each sample, intra- and inter-assay variability) of an electro-chemiluminescence (ECLIA)-based multiplex assay. METHODS: The current study describes the development of a multiplex ECLIA-based assay and characterizes the sensitivity, linear range, and inter- and intra-assay variability of the ECLIA platform and its agreement with the traditional ELISA. Special emphasis was placed on potential antigenic competition when testing closely related antigens in the multiplex format. RESULTS: Multiplexing of antigens in ECLIA provides significant practical benefits in terms of reducing sample volume requirements and experimental time. Beyond the practical advantages of multiplexing, the ECLIA provides superior assay performance when compared to the ELISA. Not only does ECLIA show good agreement with the ELISA assay, but the linear range of ECLIA is also sufficiently wide to permit single-dilution measurements of concentration without the need to do serial dilutions. The lack of antigenic competition allows the simultaneous testing of closely related antigens, such as plate antigens representing different alleles of the same protein, which can inform about cross-reactivities-or lack thereof-of serological responses. CONCLUSION: The advantages of the newly developed tool for assessing the antigen profiles of serological responses may ultimately lead to the identification of biomarkers associated with various disease stages and or protection against disease.

Characterization of two in vivo challenge models to measure functional activity of monoclonal antibodies to Plasmodium falciparum circumsporozoite protein.

BACKGROUND: New strategies are needed to reduce the incidence of malaria, and promising approaches include the development of vaccines and monoclonal antibodies (mAbs) that target the circumsporozoite protein (CSP). To select the best candidates and speed development, it is essential to standardize preclinical assays to measure the potency of such interventions in animal models. METHODS: Two assay configurations were studied using transgenic Plasmodium berghei expressing Plasmodium falciparum full-length circumsporozoite protein. The assays measured (1) reduction in parasite infection of the liver (liver burden) following an intravenous (i.v) administration of sporozoites and (2) protection from parasitaemia following mosquito bite challenge. Two human CSP mAbs, AB311 and AB317, were compared for their ability to inhibit infection. Multiple independent experiments were conducted to define assay variability and resultant impact on the ability to discriminate differences in mAb functional activity. RESULTS: Overall, the assays produced highly consistent results in that all individual experiments showed greater functional activity for AB317 compared to AB311 as calculated by the dose required for 50% inhibition (ID50) as well as the serum concentration required for 50% inhibition (IC50). The data were then used to model experimental designs with adequate statistical power to rigorously screen, compare, and rank order novel anti-CSP mAbs. CONCLUSION: The results indicate that in vivo assays described here can provide reliable information for comparing the functional activity of mAbs. The results also provide guidance regarding selection of the appropriate experimental design, dose selection, and group sizes.

Optimization of an in vivo model to study immunity to Plasmodium falciparum pre-erythrocytic stages.

BACKGROUND: The circumsporozoite protein (CSP) of Plasmodium is a key surface antigen that induces antibodies and T-cells, conferring immune protection in animal models and humans. However, much of the work on CSP and immunity has been developed based on studies using rodent or non-human primate CSP antigens, which may not be entirely translatable to CSP expressed by human malaria parasites, especially considering the host specificity of the different species. METHODS: Using a genetically engineered strain of Plasmodium berghei that expresses luciferase, GFP and the Plasmodium falciparum orthologue of CSP, the effect of laboratory preparation, mosquito treatment and mouse factors on sporozoite infectivity was assessed using an in vivo bioluminescence assay on mice. This assay was compared with a PCR-based protection assay using an already described monoclonal antibody that can provide sterile protection against sporozoite challenge. RESULTS: Bioluminescence assay demonstrated similar detection levels of the quantity and kinetics of liver-stage infection, compared to PCR-based detection. This assay was used to evaluate treatment of sporozoite and delivery method on mouse infectivity, as well as the effects of age, sex and strain of mice. Finally, this assay was used to test the protective capacity of monoclonal antibody AB317; results strongly recapitulate the findings of previous work on this antibody. CONCLUSIONS: The PbGFP-Luc line and in vivo bioluminescence imaging provide highly sensitive read-outs of liver-stage infection in mice, and this method can be useful to reliably evaluate potency of pre-erythrocytic interventions.

Using Video Telehealth to Facilitate Inhaler Training in Rural Patients with Obstructive Lung Disease.

BACKGROUND: Proper inhaler technique is important for effective drug delivery and symptom control in chronic obstructive pulmonary disease (COPD) and asthma, yet not all patients receive inhaler instructions. INTRODUCTION: Using a retrospective chart review of participants in a video telehealth inhaler training program, the study compared inhaler technique within and between monthly telehealth visits and reports associated with patient satisfaction. MATERIALS AND METHODS: Seventy-four (N = 74) rural patients prescribed ≥1 inhaler participated in three to four pharmacist telehealth inhaler training sessions using teach-to-goal (TTG) methodology. Within and between visit inhaler technique scores are compared, with descriptive statistics of pre- and postprogram survey results including program satisfaction and computer technical issues. Healthcare utilization is compared between pre- and post-training periods. RESULTS: Sixty-nine (93%) patients completed all three to four video telehealth inhaler training sessions. During the initial visit, patients demonstrated improvement in inhaler technique for metered dose inhalers (albuterol, budesonide/formoterol), dry powder inhalers (formoterol, mometasone, tiotropium), and soft mist inhalers (ipratropium/albuterol) (p < 0.01 for all). Improved inhaler technique was sustained at 2 months (p < 0.01). Ninety-four percent of participants were satisfied with the program. Although technical issues were common, occurring among 63% of attempted visits, most of these visits (87%) could be completed. There was no significant difference in emergency department visits and hospitalizations pre- and post-training. DISCUSSION: This study demonstrated high patient acceptance of video telehealth training and objective improvement in inhaler technique. CONCLUSIONS: Video telehealth inhaler training using the TTG methodology is a promising program that improved inhaler technique and access to inhaler teaching for rural patients with COPD or asthma.