FUNCTIONALLY IMPAIRED ANTIBODY RESPONSE TO BNT162B2 BOOSTER VACCINATION IN CVID IgG RESPONDERS.

BACKGROUND: While previous studies described the production of IgG-antibodies in a subgroup of CVID-patients following mRNA-vaccinations with bnt162b2 SARS-CoV2 (CVID responders), the functionality of these antibodies in terms of avidity as measured by the dissociation rate constant (kdis) and the antibody response to booster immunization has not been studied. OBJECTIVE: In CVID responders and healthy individuals the avidity of anti-SARS-CoV-2 serum-antibodies and their neutralization capacity as measured by surrogate virus neutralizing antibodies were analyzed in addition to IgG-, IgM- and IgA-antibody levels and the response of circulating follicular T-helper cells after a third vaccination with BNT162b2 SARS-CoV2 mRNA-vaccine. METHODS: Binding IgG, IgA and IgM serum levels were analyzed by ELISA in CVID-patients responding to the primary vaccination (CVID responders, n=10) and healthy controls (n=41). The binding-avidity of anti-spike antibodies was investigated using biolayer interferometry in combination with biotin-labelled receptor-binding-domain (RBD) of SARS-CoV2 spike-protein and streptavidin-labelled sensors. Antigen-specific recall T-cell responses were assessed by measuring activation-induced markers by flow cytometry. RESULTS: After the third vaccination with BNT162b2 IgG-, IgM and IgA-antibody levels, sVNT levels and antibody avidity were lower in CVID responders as compared to healthy. In contrast αSpike-avidity was comparable in CVID responders and healthy individuals following primary vaccination. Follicular T-helper cell response to booster vaccination in CVID-responders was significantly reduced when compared to healthy individuals. CONCLUSION: Impaired affinity-maturation during booster-response provides new insight into CVID pathophysiology.

Antigen-Specific CD4+ T-Cell Activation in Primary Antibody Deficiency After BNT162b2 mRNA COVID-19 Vaccination

Previous studies on immune responses following COVID-19 vaccination in patients with common variable immunodeficiency (CVID) were inconclusive with respect to the ability of the patients to produce vaccine-specific IgG antibodies, while patients with milder forms of primary antibody deficiency such as immunoglobulin isotype deficiency or selective antibody deficiency have not been studied at all. In this study we examined antigen-specific activation of CXCR5-positive and CXCR5-negative CD4+ memory cells and also isotype-specific and functional antibody responses in patients with CVID as compared to other milder forms of primary antibody deficiency and healthy controls six weeks after the second dose of BNT162b2 vaccine against SARS-CoV-2. Expression of the activation markers CD25 and CD134 was examined by multi-color flow cytometry on CD4+ T cell subsets stimulated with SARS-CoV-2 spike peptides, while in parallel IgG and IgA antibodies and surrogate virus neutralization antibodies against SARS-CoV-2 spike protein were measured by ELISA. The results show that in CVID and patients with other milder forms of antibody deficiency normal IgG responses (titers of spike protein-specific IgG three times the detection limit or more) were associated with intact vaccine-specific activation of CXCR5-negative CD4+ memory T cells, despite defective activation of circulating T follicular helper cells. In contrast, CVID IgG nonresponders showed defective vaccine-specific and superantigen-induced activation of both CD4+T cell subsets. In conclusion, impaired TCR-mediated activation of CXCR5-negative CD4+ memory T cells following stimulation with vaccine antigen or superantigen identifies patients with primary antibody deficiency and impaired IgG responses after BNT162b2 vaccination.

A Model Predicting Mortality of Hospitalized Covid-19 Patients Four Days After Admission: Development, Internal and Temporal-External Validation.

Objective: To develop and validate a prognostic model for in-hospital mortality after four days based on age, fever at admission and five haematological parameters routinely measured in hospitalized Covid-19 patients during the first four days after admission. Methods: Haematological parameters measured during the first 4 days after admission were subjected to a linear mixed model to obtain patient-specific intercepts and slopes for each parameter. A prediction model was built using logistic regression with variable selection and shrinkage factor estimation supported by bootstrapping. Model development was based on 481 survivors and 97 non-survivors, hospitalized before the occurrence of mutations. Internal validation was done by 10-fold cross-validation. The model was temporally-externally validated in 299 survivors and 42 non-survivors hospitalized when the Alpha variant (B.1.1.7) was prevalent. Results: The final model included age, fever on admission as well as the slope or intercept of lactate dehydrogenase, platelet count, C-reactive protein, and creatinine. Tenfold cross validation resulted in a mean area under the receiver operating characteristic curve (AUROC) of 0.92, a mean calibration slope of 1.0023 and a Brier score of 0.076. At temporal-external validation, application of the previously developed model showed an AUROC of 0.88, a calibration slope of 0.95 and a Brier score of 0.073. Regarding the relative importance of the variables, the (apparent) variation in mortality explained by the six variables deduced from the haematological parameters measured during the first four days is higher (explained variation 0.295) than that of age (0.210). Conclusions: The presented model requires only variables routinely acquired in hospitals, which allows immediate and wide-spread use as a decision support for earlier discharge of low-risk patients to reduce the burden on the health care system. Clinical Trial Registration: Austrian Coronavirus Adaptive Clinical Trial (ACOVACT); ClinicalTrials.gov, identifier NCT04351724.

Quantitative and Functional Assessment of the Influence of Routinely Used Cryopreservation Media on Mononuclear Leukocytes for Medical Research.

Quantitative and functional analysis of mononuclear leukocyte populations is an invaluable tool to understand the role of the immune system in the pathogenesis of a disease. Cryopreservation of mononuclear cells (MNCs) is routinely used to guarantee similar experimental conditions. Immune cells react differently to cryopreservation, and populations and functions of immune cells change during the process of freeze-thawing. To allow for a setup that preserves cell number and function optimally, we tested four different cryopreservation media. MNCs from 15 human individuals were analyzed. Before freezing and after thawing, the distribution of leukocytes was quantified by flow cytometry. Cultured cells were stimulated using lipopolysaccharide, and their immune response was quantified by flow cytometry, quantitative polymerase chain reaction (qPCR), and enzyme-linked immunosorbent assay (ELISA). Ultimately, the performance of the cryopreservation media was ranked. Cell recovery and viability were different between the media. Cryopreservation led to changes in the relative number of monocytes, T cells, B cells, and their subsets. The inflammatory response of MNCs was altered by cryopreservation, enhancing the basal production of inflammatory cytokines. Different cryopreservation media induce biases, which needs to be considered when designing a study relying on cryopreservation. Here, we provide an overview of four different cryopreservation media for choosing the optimal medium for a specific task.

Heparin-Functionalized Adsorbents Eliminate Central Effectors of Immunothrombosis, including Platelet Factor 4, High-Mobility Group Box 1 Protein and Histones.

Inflammation and thrombosis are closely intertwined in numerous disorders, including ischemic events and sepsis, as well as coronavirus disease 2019 (COVID-19). Thrombotic complications are markers of disease severity in both sepsis and COVID-19 and are associated with multiorgan failure and increased mortality. Immunothrombosis is driven by the complement/tissue factor/neutrophil axis, as well as by activated platelets, which can trigger the release of neutrophil extracellular traps (NETs) and release further effectors of immunothrombosis, including platelet factor 4 (PF4/CXCL4) and high-mobility box 1 protein (HMGB1). Many of the central effectors of deregulated immunothrombosis, including activated platelets and platelet-derived extracellular vesicles (pEVs) expressing PF4, soluble PF4, HMGB1, histones, as well as histone-decorated NETs, are positively charged and thus bind to heparin. Here, we provide evidence that adsorbents functionalized with endpoint-attached heparin efficiently deplete activated platelets, pEVs, PF4, HMGB1 and histones/nucleosomes. We propose that this elimination of central effectors of immunothrombosis, rather than direct binding of pathogens, could be of clinical relevance for mitigating thrombotic complications in sepsis or COVID-19 using heparin-functionalized adsorbents.

COVID-19-related adaptations to the implementation and evaluation of a clinic-based intervention designed to improve opioid safety.

The United States faces an opioid crisis with an unprecedented and increasing death rate from opioid overdose. Successfully reducing the rates of opioid use disorder (OUD) and overdose will require the engagement of frontline clinicians to prescribe opioids more safely and to build their capacity to treat patients with OUD using evidence-based approaches. The COVID-19 pandemic has created significant challenges for patients, clinicians and health systems and has been associated with increasing risks of overdoses and deaths. Herein, we review a multidisciplinary project designed to implement and evaluate clinic-based interventions in Oregon, USA, to improve pain management, opioid prescribing and treatment of OUD. The intervention, called Improving PaIn aNd OPiOId MaNagemenT in Primary Care (PINPOINT), combines practice facilitation, academic detailing and education through the Oregon ECHO Network. Implementation of PINPOINT has occurred across the Oregon Rural Practice-based Research Network and has involved 49 clinic sites to date. To evaluate the impact of the intervention, the research team created the Provider Results of Opioid Management and Prescribing Training (PROMPT), a dataset that links information from the state prescription drug monitoring program, all-payer claims database, emergency medical services, vital records and substance use disorder treatment system. The PROMPT dataset will allow evaluation of the impact of the intervention at both the clinician and clinic levels. Due to the constraints of the COVID-19 pandemic, elements of both implementation and evaluation required significant adaptations to continue to meet the original project goals.

Safety of Tenofovir Disoproxil Fumarate for Pregnant Women Facing the Coronavirus Disease 2019 Pandemic.

We assessed the teratogenicity of tenofovir, a human immunodeficiency virus (HIV) drug similar to remdesivir that is currently being evaluated for the treatment of coronavirus disease 2019 (COVID-19). Using US Medicaid Analytic eXtract (MAX) claims data (2000-2014), we identified a population-based pregnancy cohort of women with HIV who filled at least 1 prescription for antiretroviral therapies (ART) during the first trimester. Women on tenofovir disoproxil fumarate (TDF) were compared with women receiving ART without TDF. Major malformations were identified by International Classification of Diseases, Ninth Revision, codes using validated algorithms. Relative risks and 95% confidence intervals were estimated using propensity score stratification to control for potential confounders. We incorporated the results into prior knowledge by conducting a systematic literature review and a meta-analysis. Major congenital malformations were diagnosed in 37 out of 866 (4.27%) infants exposed to TDF and 38 out of 1,020 (3.73%) infants exposed to ART other than TDF; the adjusted relative risk was 1.21 (95% confidence interval: 0.77, 1.90). Estimates for specific malformations were imprecise. The pooled relative risk from the meta-analysis with 6 prior studies was 0.88 (95% confidence interval: 0.75, 1.03). Based on evidence accumulated in patients with HIV, first-trimester TDF use does not increase the risk of major congenital malformations overall in the newborn compared with other ART.

Academic Detailing to Increase Prescribing of HIV Pre-exposure Prophylaxis.

Although HIV pre-exposure prophylaxis can decrease new cases of HIV by up to 99%, many patients who could benefit from pre-exposure prophylaxis never receive prescriptions for it. Because pre-exposure prophylaxis is indicated for patients who do not have an infectious disease, increasing pre-exposure prophylaxis prescribing by primary care and generalist clinicians represents a key element of the Ending the HIV Epidemic in the U.S. initiative. This review provides an overview of academic detailing and how it is currently being used to increase pre-exposure prophylaxis prescribing. Academic detailing is outreach education that engages with clinicians in 1-to-1 or small group interactions focused on identifying and addressing an individual clinician's needs to increase their use of evidence-based practices. Academic detailing has been proven in multiple previous research studies, and the principles required for successful implementation include interactivity, clinical relevance of content, and focus on defined behavior change objectives. Clinician barriers to pre-exposure prophylaxis prescribing may occur in the domains of knowledge, attitudes, or behavior, and academic detailing has the potential to address all of these areas. State and local health departments have developed academic detailing programs focused on pre-exposure prophylaxis prescribing and other elements of HIV prevention-sometimes describing the approach as public health detailing. Few studies of academic detailing for pre-exposure prophylaxis have been published to date; rigorous evaluation of HIV-specific adaptations and innovations of the approach would represent an important contribution. In the setting of the COVID-19 pandemic, interest in virtual delivery of academic detailing has grown, which could inform efforts to implement academic detailing in rural communities and other underserved areas. Increasing this capacity could make an important contribution to Ending the HIV Epidemic in the U.S. and other HIV prevention efforts.

Non-Visit-Based and Non-Infection-Related Antibiotic Use in the US: A Cohort Study of Privately Insured Patients During 2016-2018.

BACKGROUND: Ambulatory antibiotic prescriptions without a clinic visit or without documentation of infection could represent overuse and contribute to adverse outcomes. We aim to describe US ambulatory antibiotic prescribing, including those without an associated visit or infection diagnosis. METHODS: We conducted an observational cohort study using data of all patients receiving antibacterial, antibiotic prescriptions from 04/01/2016 to 06/30/2018 in a large US private health insurance plan. We identified outpatient antibiotic prescriptions as (1) associated with a clinician visit and an infection-related diagnosis; (2) associated with a clinician visit but no infection-related diagnosis; or (3) not associated with an in-person clinician visit in the 7 days before the prescription (non-visit-based). We then assessed whether non-visit-based antibiotic prescriptions (NVBAPs) differed from visit-based antibiotics by patient, clinician, or antibiotic characteristics using multivariable models. RESULTS: The cohort included 8.6M enrollees who filled 22.3M antibiotic prescriptions. NVBAP accounted for 31% (6.9M) of fills, and non-infection-related prescribing accounted for 22% (4.9M). NVBAP rates were lower for children than for adults (0-17 years old, 16%; 18-64 years old, 33%; >65 years old, 34%). Among most commonly prescribed antibiotic classes, NVBAP was highest for penicillins (36%) and lowest for cephalosporins (25%) and macrolides (25%). Specialist physicians had the highest rate of NVBAP (38%), followed by internists (28%), family medicine (20%), and pediatricians (10%). In multivariable models, NVBAP was associated with increasing age, and NVBAP was less likely for patients in the South, those with more baseline clinical visits, or those with chronic lung disease. CONCLUSIONS: Over half of ambulatory antibiotic use was either non-visit-based or non-infection-related. Particularly given health care changes due to the coronavirus disease 2019 pandemic, efforts to improve antibiotic prescribing must account for non-visit-based and non-infection-related prescribing.