Outer membrane vesicles as a platform for the discovery of antibodies to bacterial pathogens.

Bacterial outer membrane vesicles (OMVs) are nanosized spheroidal particles shed by gram-negative bacteria that contain biomolecules derived from the periplasmic space, the bacterial outer membrane, and possibly other compartments. OMVs can be purified from bacterial culture supernatants, and by genetically manipulating the bacterial cells that produce them, they can be engineered to harbor cargoes and/or display molecules of interest on their surfaces including antigens that are immunogenic in mammals. Since OMV bilayer-embedded components presumably maintain their native structures, OMVs may represent highly useful tools for generating antibodies to bacterial outer membrane targets. OMVs have historically been utilized as vaccines or vaccine constituents. Antibodies that target bacterial surfaces are increasingly being explored as antimicrobial agents either in unmodified form or as targeting moieties for bactericidal compounds. Here, we review the properties of OMVs, their use as immunogens, and their ability to elicit antibody responses against bacterial antigens. We highlight antigens from bacterial pathogens that have been successfully targeted using antibodies derived from OMV-based immunization and describe opportunities and limitations for OMVs as a platform for antimicrobial antibody development. KEY POINTS: • Outer membrane vesicles (OMVs) of gram-negative bacteria bear cell-surface molecules • OMV immunization allows rapid antibody (Ab) isolation to bacterial membrane targets • Review and analysis of OMV-based immunogens for antimicrobial Ab development.

EMS Bypass to Endovascular Stroke Centers is Associated with Shorter Time to Thrombolysis and Thrombectomy for LVO Stroke.

OBJECTIVES: Large vessel occlusion (LVO) strokes may be eligible for treatment with intravenous thrombolysis (IVT) and endovascular therapy (EVT). Patients selected for treatment have better neurologic outcomes with EVT, and delays in this therapy lead to worse outcomes. However, EVT is offered at a limited number of hospitals, referred to as endovascular stroke centers (ESC). This poses a difficult decision for EMS: to take potential stroke patients to the closest primary stroke center (PSC) or longer transport time to a more distant ESC. We hypothesized that patients with LVO stroke undergoing EVT transported directly to an ESC would have more favorable outcomes as measured by the modified Rankin scale (mRS) at 90 days, compared to transport to a PSC followed by transfer to an ESC. METHODS: The OPUS-REACH consortium examined transportation patterns and outcomes in patients with LVO stroke who received endovascular treatment. This cohort includes 2400 patients with LVO stroke throughout eight endovascular centers in the Northeast U.S. from 2015 to 2020. All patients enrolled in the OPUS-REACH database were eligible for inclusion. Patients were excluded if they were missing the pickup address, had an in-hospital stroke, or arrived via mobile stroke unit. The remaining patients were separated into two groups: the bypass group, with transportation by EMS to an ESC by bypassing PSC, and the non-bypass group, with initial transport to PSC and interfacility transport to an ESC. The primary outcome was the modified Rankin scale (mRS) at 90 days, where 0-2 was defined as "good". RESULTS: The primary outcome did not reach significance with 40% of the bypass group as compared with the 33.1% of the non-bypass group having a "good" outcome. However, the bypass group underwent shorter times from last-known-well to both thrombolysis (120.9 vs 153.3 min, p < 0.001) and thrombectomy (356.1 vs 454.8 min, p = 0.001). CONCLUSIONS: In patients with LVO stroke who undergo thrombectomy, EMS transport directly to an ESC results in shorter time thrombectomy, although we did not observe a difference in 90-day functional outcomes. Additionally, bypass to reach a more capable endovascular stroke center does not delay administration of IVT from time of LKW.

Landscape analysis of environmental data sources for linkage with SEER cancer patients database.

One of the challenges associated with understanding environmental impacts on cancer risk and outcomes is estimating potential exposures of individuals diagnosed with cancer to adverse environmental conditions over the life course. Historically, this has been partly due to the lack of reliable measures of cancer patients' potential environmental exposures before a cancer diagnosis. The emerging sources of cancer-related spatiotemporal environmental data and residential history information, coupled with novel technologies for data extraction and linkage, present an opportunity to integrate these data into the existing cancer surveillance data infrastructure, thereby facilitating more comprehensive assessment of cancer risk and outcomes. In this paper, we performed a landscape analysis of the available environmental data sources that could be linked to historical residential address information of cancer patients' records collected by the National Cancer Institute's Surveillance, Epidemiology, and End Results Program. The objective is to enable researchers to use these data to assess potential exposures at the time of cancer initiation through the time of diagnosis and even after diagnosis. The paper addresses the challenges associated with data collection and completeness at various spatial and temporal scales, as well as opportunities and directions for future research.

Evaluating the Effects of Food Deserts and Food Swamps in an Urban Burn Patient Population.

Poverty is a known risk factor for burn injury and is associated with residency in food deserts and food swamps. Our aim was to determine the prevalence of residency in food deserts and food swamps and to investigate the relationship between food environment, comorbidities, and wound healing in patients with burns. We performed a retrospective chart review of all patients with burns aged ≥ 18 seen in the emergency department or admitted to the burn service at an American Burn Association-verified urban academic center between January 2016 and January 2022. Patient GeoIDs were used to classify residency in food deserts and food swamps, and comorbidities and demographics were recorded. A subset of patients with <20% total body surface area burns who underwent single-operation split-thickness skin grafting was identified for wound healing analysis. A total of 3063 patients were included, with 206 in the heal time analysis. In total, 2490 (81.3%) lived in food swamps and 96 (3.1%) lived in food deserts. Diabetes, hypertension, and tobacco smoking were more prevalent in food swamps than in food deserts or good access areas. While there was no significant effect of the food environment on wound healing, diabetes was associated with longer healing times. Most patients with burns reside in food swamps, which are associated with a higher prevalence of hypertension, diabetes, and smoking. The food environment was not significantly associated with wound healing. Not having diabetes was associated with a shorter time for wound healing.

An exploratory analysis of the impact of area-level exposome on geographic disparities in aggressive prostate cancer.

Numbers of aggressive prostate cancer (aPC) cases are rising, but only a few risk factors have been identified. In this study, we introduce a systematic approach to integrate geospatial data into external exposome research using aPC cases from Pennsylvania. We demonstrate the association between several area-level exposome measures across five Social Determinants of Health domains (SDOH) and geographic areas identified as having elevated odds of aPC. Residential locations of Pennsylvania men diagnosed with aPC from 2005 to 2017 were linked to 37 county-/tract-level SDOH exosome measures. Variable reduction processes adopted from neighborhood-wide association study along with Bayesian geoadditive logistic regression were used to identify areas with elevated odds of aPC and exposome factors that significantly attenuated the odds and reduced the size of identified areas. Areas with significantly higher odds of aPC were explained by various SDOH exposome measures, though the extent of the reduction depended on geographic location. Some areas were associated with race (social context), health insurance (access), or tract-level poverty (economics), while others were associated with either county-level water quality or a combination of factors. Area-level exposome measures can guide future patient-level external exposome research and help design targeted interventions to reduce local cancer burden.

The Association Between a Neighborhood Adverse Childhood Experiences Index and Body Mass Index Among New York City Youth.

Background: The role of neighborhood factors in the association between adverse childhood experiences (ACEs) and body mass index (BMI) has not been widely studied. A neighborhood ACEs index (NAI) captures neighborhood environment factors associated with ACE exposure. This study examined associations between BMI and an NAI among New York City (NYC) youth. An exploratory objective examined the NAI geographic distribution across NYC neighborhoods. Methods: Data for students attending NYC public general education schools in kindergarten-12th grade from 2006-2017 (n = 1,753,867) were linked to 25 geospatial datasets capturing neighborhood characteristics for every census tract in NYC. Multivariable hierarchical linear regression tested associations between BMI and the NAI; analyses also were conducted by young (<8 years), school age (8-12 years), and adolescent (>12 years) subgroups. In addition, NAI was mapped by census tract, and local Moran's I identified clusters of high and low NAI neighborhoods. Results: Higher BMI was associated with higher NAI across all sex and age groups, with largest magnitude of associations for girls (medium NAI vs. low NAI: unstandardized ß = 0.112 (SE 0.008), standardized ß [effect size]=0.097, p < 0.001; high NAI vs. low NAI: unstandardized ß = 0.195 (SE 0.008), standardized ß = 0.178, p < 0.001) and adolescents (medium NAI vs. low NAI: unstandardized ß = 0.189 (SE 0.014), standardized ß = 0.161, p < 0.001, high NAI vs. low NAI: unstandardized ß = 0.364 (SE 0.015), standardized ß = 0.334, p < 0.001 for adolescent girls; medium NAI vs. low NAI: unstandardized ß = 0.122 (SE 0.014), standardized ß = 0.095, p < 0.001, high NAI vs. low NAI: unstandardized ß = 0.217 (SE 0.015), standardized ß = 0.187, p < 0.001 for adolescent boys). Each borough of NYC included clusters of neighborhoods with higher and lower NAI exposure, although clusters varied in size and patterns of geographic dispersion across boroughs. Conclusions: A spatial index capturing neighborhood environment factors associated with ACE exposure is associated with higher BMI among NYC youth. Findings complement prior literature about relationships between neighborhood environment and obesity risk, existing research documenting ACE-obesity associations, and the potential for neighborhood factors to be a source of adversity. Collectively, evidence suggests that trauma-informed place-based obesity reduction efforts merit further exploration as potential means to interrupt ACE-obesity associations.

Structural Basis for Multivalent MUC16 Recognition and Robust Anti-Pancreatic Cancer Activity of Humanized Antibody AR9.6.

Mucin-16 (MUC16) is a target for antibody-mediated immunotherapy in pancreatic ductal adenocarcinoma (PDAC) among other malignancies. The MUC16-specific monoclonal antibody AR9.6 has shown promise for PDAC immunotherapy and imaging. Here, we report the structural and biological characterization of the humanized AR9.6 antibody (huAR9.6). The structure of huAR9.6 was determined in complex with a MUC16 SEA (Sea urchin sperm, Enterokinase, Agrin) domain. Binding of huAR9.6 to recombinant, shed, and cell-surface MUC16 was characterized, and anti-PDAC activity was evaluated in vitro and in vivo. HuAR9.6 bound a discontinuous, SEA domain epitope with an overall affinity of 88 nmol/L. Binding affinity depended on the specific SEA domain(s) present, and glycosylation modestly enhanced affinity driven by favorable entropy and enthalpy and via distinct transition state thermodynamic pathways. Treatment with huAR9.6 reduced the in vitro growth, migration, invasion, and clonogenicity of MUC16-positive PDAC cells and patient-derived organoids (PDO). HuAR9.6 blocked MUC16-mediated ErbB and AKT activation in PDAC cells, PDOs, and patient-derived xenografts and induced antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity. More importantly, huAR9.6 treatment caused substantial PDAC regression in subcutaneous and orthotopic tumor models. The mechanism of action of huAR9.6 may depend on dense avid binding to homologous SEA domains on MUC16. The results of this study validate the translational therapeutic potential of huAR9.6 against MUC16-positive PDACs.

Targeting axonal guidance dependencies in glioblastoma with ROBO1 CAR T cells.

Resistance to genotoxic therapies and tumor recurrence are hallmarks of glioblastoma (GBM), an aggressive brain tumor. In this study, we investigated functional drivers of post-treatment recurrent GBM through integrative genomic analyses, genome-wide genetic perturbation screens in patient-derived GBM models and independent lines of validation. Specific genetic dependencies were found consistent across recurrent tumor models, accompanied by increased mutational burden and differential transcript and protein expression compared to its primary GBM predecessor. Our observations suggest a multi-layered genetic response to drive tumor recurrence and implicate PTP4A2 (protein tyrosine phosphatase 4A2) as a modulator of self-renewal, proliferation and tumorigenicity in recurrent GBM. Genetic perturbation or small-molecule inhibition of PTP4A2 acts through a dephosphorylation axis with roundabout guidance receptor 1 (ROBO1) and its downstream molecular players, exploiting a functional dependency on ROBO signaling. Because a pan-PTP4A inhibitor was limited by poor penetrance across the blood-brain barrier in vivo, we engineered a second-generation chimeric antigen receptor (CAR) T cell therapy against ROBO1, a cell surface receptor enriched across recurrent GBM specimens. A single dose of ROBO1-targeted CAR T cells doubled median survival in cell-line-derived xenograft (CDX) models of recurrent GBM. Moreover, in CDX models of adult lung-to-brain metastases and pediatric relapsed medulloblastoma, ROBO1 CAR T cells eradicated tumors in 50-100% of mice. Our study identifies a promising multi-targetable PTP4A-ROBO1 signaling axis that drives tumorigenicity in recurrent GBM, with potential in other malignant brain tumors.