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Most immunoglobulin (Ig) domains bear only a single highly conserved canonical intradomain, inter-ß-sheet disulfide linkage formed between Cys23-Cys104, and incorporation of rare noncanonical disulfide linkages at other locations can enhance Ig domain stability. Here, we exhaustively surveyed the sequence tolerance of Ig variable (V) domain framework regions (FRs) to noncanonical disulfide linkages. Starting from a destabilized VH domain lacking a Cys23-Cys104 disulfide linkage, we generated and screened phage-displayed libraries of engineered VHs, bearing all possible pairwise combinations of Cys residues in neighboring ß-strands of the Ig fold FRs. This approach identified seven novel Cys pairs in VH FRs (Cys4-Cys25, Cys4-Cys118, Cys5-Cys120, Cys6-Cys119, Cys22-Cys88, Cys24-Cys86, and Cys45-Cys100; the international ImMunoGeneTics information system numbering), whose presence rescued domain folding and stability. Introduction of a subset of these noncanonical disulfide linkages (three intra-ß-sheet: Cys4-Cys25, Cys22-Cys88, and Cys24-Cys86, and one inter-ß-sheet: Cys6-Cys119) into a diverse panel of VH, VL, and VHH domains enhanced their thermostability and protease resistance without significantly impacting expression, solubility, or binding to cognate antigens. None of the noncanonical disulfide linkages identified were present in the natural human VH repertoire. These data reveal an unexpected permissiveness of Ig V domains to noncanonical disulfide linkages at diverse locations in FRs, absent in the human repertoire, whose presence is compatible with antigen recognition and improves domain stability. Our work represents the most complete assessment to date of the role of engineered noncanonical disulfide bonding within FRs in Ig V domain structure and function.
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Região Variável de Imunoglobulina , Humanos , Sequência de Aminoácidos , Técnicas de Visualização da Superfície Celular , Região Variável de Imunoglobulina/química , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/metabolismo , Domínios Proteicos/genética , Escherichia coli/genética , Dobramento de ProteínaRESUMO
BACKGROUND: Hispanic or Latino populations (hereafter, "Latinos") are a rapidly expanding U.S. demographic and have documented inequities in preventable diseases and conditions. Many Latinos reside in ethnic enclaves, and understanding the context and healthcare accessibility within these places is critical. OBJECTIVE: This study described the neighborhood social and built environment attributes of Latino enclaves and evaluated associations between enclaves and geographic healthcare accessibility. DESIGN: Cross-sectional ecologic analysis. SUBJECTS: Our unit of analysis was all neighborhoods (n ~ 20,000 census tracts) in California, Florida, New Jersey, New York, and Texas in years 2000 and 2010. MAIN MEASURES: The primary exposure of interest, "Latino enclaves," was defined using neighborhood-level data on the percentage of Latino residents, foreign-born Latinos, Spanish speakers with limited English proficiency, and linguistically isolated Spanish-speaking households. The primary outcome was a neighborhood-level measure of geographic healthcare accessibility of primary care physicians, which accounted for both the supply of physicians and population demand for healthcare (i.e., population size within driving distance). RESULTS: Approximately 30% of neighborhoods were classified as Latino enclaves, 87% of which were enclaves in both 2000 and 2010. Compared with non-enclaves, Latino enclaves had more markers of structural disadvantage including having higher proportions of poverty, uninsured individuals, crowded housing, and higher crime scores. Results from multivariable models suggest that more culturally distinct neighborhoods (i.e., higher enclave score) had lower healthcare accessibility, though when stratified, this association persisted only in high (≥ 20%) poverty neighborhoods. CONCLUSION: This study highlights several neighborhood structural disadvantages within Latino enclaves, including higher poverty, uninsured individuals, and crime compared to non-enclave neighborhoods. Moreover, our findings point to the need for interventions aimed at improving healthcare accessibility particularly within socioeconomically disadvantaged Latino enclaves. Addressing these inequities demands multifaceted approaches that consider both social and structural factors to ensure equitable healthcare access for Latino populations.
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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.
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Anti-Infecciosos , Antígenos de Bactérias , Animais , Proteínas da Membrana Bacteriana Externa , Anticorpos , Bactérias Gram-Negativas , Anticorpos Antibacterianos , Vacinas Bacterianas , MamíferosRESUMO
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.
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BACKGROUND: Examining temporal and spatial diffusion of a new technology, such as digital mammography, can provide important insights into potential disparities associated with access to new medical technologies and how quickly these technologies are adopted. Although digital mammography is currently a standard technology in the United States for breast cancer screening, its adoption and geographic diffusion, as medical facilities transitioned from film to digital units, has not been explored well. METHODS: This study evaluated the geographic diffusion of digital mammography facilities from 2001 to 2014 in the contiguous United States (excluding Alaska and Hawaii) and estimated the geographic accessibility to this new technology for women aged ≥45 years at the census tract level within a 20-minute drivetime by population density, rural/urban residence, and race/ethnicity. The number of mammography units by technology type (film or digital) and density per 10,000 women were also summarized. RESULTS: The adoption of digital mammography advanced first in densely populated regions and last in remote rural areas. Overall, proportion of digital mammography units increased from 1.4% in 2001 to 94.6% in 2014, but since 2008, there was a decline in density of units from 2.31 per 10,000 women aged ≥45 years to 1.97 in 2014. In 2014, approximately 87% of women aged ≥45 years in the contiguous United States had accessibility to digital mammography, but this proportion was substantially lower for Native American women (67%) and rural residents (32%). CONCLUSION: Understanding the diffusion of and accessibility to digital mammography may help predict future medical technology diffusion and assess its role in geographic differences in cancer diagnosis and treatment.
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Neoplasias da Mama , Programas de Rastreamento , Estados Unidos/epidemiologia , Feminino , Humanos , Mamografia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Detecção Precoce de Câncer , Havaí , Acessibilidade aos Serviços de SaúdeRESUMO
BACKGROUND: Spatial analysis can identify communities where men are at risk for aggressive prostate cancer (PCan) and need intervention. However, there are several definitions for aggressive PCan. In this study, we evaluate geospatial patterns of 3 different aggressive PCan definitions in relation to PCan-specific mortality and provide methodologic and practical insights into how each definition may affect intervention targets. METHODS: Using the Pennsylvania State Cancer Registry data (2005-2015), we used 3 definitions to assign "aggressive" status to patients diagnosed with PCan. Definition one (D1, recently recommended as the primary definition, given high correlation with PCan death) was based on staging criteria T4/N1/M1 or Gleason score ≥ 8. Definition two (D2, most frequently-used definition in geospatial studies) included distant SEER summary stage. Definition three (D3) included Gleason score ≥ 7 only. Using Bayesian spatial models, we identified geographic clusters of elevated odds ratios for aggressive PCan (binomial model) for each definition and compared overlap between those clusters to clusters of elevated hazard ratios for PCan-specific mortality (Cox regression). RESULTS: The number of "aggressive" PCan cases varied by definition, and influenced quantity, location, and extent/size of geographic clusters in binomial models. While spatial patterns overlapped across all three definitions, using D2 in binomial models provided results most akin to PCan-specific mortality clusters as identified through Cox regression. This approach resulted in fewer clusters for targeted intervention and less sensitive to missing data compared to definitions that rely on clinical TNM staging. CONCLUSIONS: Using D2, based on distant SEER summary stage, in future research may facilitate consistency and allow for standardized comparison across geospatial studies.
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Neoplasias da Próstata , Masculino , Humanos , Teorema de Bayes , Próstata/patologia , Antígeno Prostático Específico , Estadiamento de NeoplasiasRESUMO
Acinetobacter baumannii is a Gram-negative bacterial pathogen that exhibits high intrinsic resistance to antimicrobials, with treatment often requiring the use of last-resort antibiotics. Antibiotic-resistant strains have become increasingly prevalent, underscoring a need for new therapeutic interventions. The aim of this study was to use A. baumannii outer membrane vesicles as immunogens to generate single-domain antibodies (VHHs) against bacterial cell surface targets. Llama immunization with the outer membrane vesicle preparations from four A. baumannii strains (ATCC 19606, ATCC 17961, ATCC 17975, and LAC-4) elicited a strong heavy-chain IgG response, and VHHs were selected against cell surface and/or extracellular targets. For one VHH, OMV81, the target antigen was identified using a combination of gel electrophoresis, mass spectrometry, and binding studies. Using these techniques, OMV81 was shown to specifically recognize CsuA/B, a protein subunit of the Csu pilus, with an equilibrium dissociation constant of 17 nM. OMV81 specifically bound to intact A. baumannii cells, highlighting its potential use as a targeting agent. We anticipate the ability to generate antigen-specific antibodies against cell surface A. baumannii targets could provide tools for further study and treatment of this pathogen. KEY POINTS: â¢Llama immunization with bacterial OMV preparations for VHH generation â¢A. baumannii CsuA/B, a pilus subunit, identified by mass spectrometry as VHH target â¢High-affinity and specific VHH binding to CsuA/B and A. baumannii cells.
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Acinetobacter baumannii , Camelídeos Americanos , Animais , Acinetobacter baumannii/metabolismo , Membrana Celular/metabolismo , Antibacterianos/metabolismo , Proteínas de Membrana/metabolismoRESUMO
BACKGROUND: In response to citizens' concerns about elevated cancer incidence in their locales, US CDC proposed publishing cancer incidence at sub-county scales. At these scales, confidence in patients' residential geolocation becomes a key constraint of geospatial analysis. To support monitoring cancer incidence in sub-county areas, we presented summary metrics to numerically delimit confidence in residential geolocation. RESULTS: We defined a concept of Residential Address Discriminant Power (RADP) as theoretically perfect within all residential addresses and its practical application, i.e., using Emergency Dispatch (ED) Address Point Candidates of Equivalent Likelihood (CEL) to quantify Residential Geolocation Discriminant Power (RGDP) to approximate RADP. Leveraging different productivity of probabilistic, deterministic, and interactive geocoding record linkage, we simultaneously detected CEL for 5,807 cancer cases reported to North Carolina Central Cancer Registry (NC CCR)- in January 2022. Batch-match probabilistic and deterministic algorithms matched 86.0% cases to their unique ED address point candidates or a CEL, 4.4% to parcel site address, and 1.4% to street centerline. Interactively geocoded cases were 8.2%. To demonstrate differences in residential geolocation confidence between enumeration areas, we calculated sRGDP for cancer cases by county and assessed the existing uncertainty within the ED data, i.e., identified duplicate addresses (as CEL) for each ED address point in the 2014 version of the NC ED data and calculated ED_sRGDP by county. Both summary RGDP (sRGDP) (0.62-1.00) and ED_sRGDP (0.36-1.00) varied across counties and were lower in rural counties (p < 0.05); sRGDP correlated with ED_sRGDP (r = 0.42, p < 0.001). The discussion covered multiple conceptual and economic issues attendant to quantifying confidence in residential geolocation and presented a set of organizing principles for future work. CONCLUSIONS: Our methodology produces simple metrics - sRGDP - to capture confidence in residential geolocation via leveraging ED address points as CEL. Two facts demonstrate the usefulness of sRGDP as area-based summary metrics: sRGDP variability between counties and the overall lower quality of residential geolocation in rural vs. urban counties. Low sRGDP for the cancer cases within the area of interest helps manage expectations for the uncertainty in cancer incidence data. By supplementing cancer incidence data with sRGDP and ED_sRGDP, CCRs can demonstrate transparency in geocoding success, which may help win citizen trust.
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Algoritmos , Mapeamento Geográfico , Humanos , North Carolina , Sistema de Registros , Informática MédicaRESUMO
OBJECTIVES: Disparities exist throughout our healthcare system, especially related to access to care. Advanced stroke care for strokes is only available at selected endovascular centers (ESCs) in the United States. Although the number of ESCs increase each year, this does not necessarily reflect increased access to care. Here, we look at the evolution of ESC in four states and disparities in access to advanced stroke care. MATERIALS AND METHODS: This is a descriptive study of access to ESCs in four Northeastern states between 2015-2019. Using data from the United States Census Bureau and spatial analysis, we examined the proportion of the population with drive times of less than 60 minutes stratified by income, race/ethnicity, population density, and insurance. We also calculated the mean drive time for each of these socioeconomic groups from their census tracts to the nearest ESC. RESULTS: Between 2015 and 2019, the number of ESCs increased from 15 to 48. The proportion of patients within a 60-minute drive of an ESC increased from 77% to 88%. However, only 66% of the least densely populated quartile lived within 60 min of an ESC. By income, access to ESCs in the wealthiest quartile was 96.6% compared to 83.7% in the lowest quartile. Hispanics and non-Hispanic Blacks had the largest proportions of populations within 60 minutes of an ESC while Non-Hispanic Whites had the smallest. CONCLUSIONS: This study underscores the need to evaluate the placement of new ESCs to assure that these hospitals decrease disparities and increase access to advanced stroke care.
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Disparidades em Assistência à Saúde , Acidente Vascular Cerebral , Humanos , Estados Unidos/epidemiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Etnicidade , Hispânico ou Latino , População Branca , Acessibilidade aos Serviços de SaúdeRESUMO
BACKGROUND: Large vessel occlusion (LVO) strokes are best treated with rapid endovascular therapy (EVT). There are two routes that LVO stroke patients can take to EVT therapy when transported by EMS: primary transport (ambulance transports directly to an endovascular stroke center (ESC) or secondary transport (EMS transports to a non-ESC then transfers for EVT). There is no clear evidence which path to care results in better functional outcomes for LVO stroke patients. To find this answer, an analysis of a large, real-world population of LVO stroke patients must be performed. METHODS: A pragmatic registry of LVO stroke patients from nine health systems across the United States. The nine health systems span urban and rural populations as well as the spectrum of socioeconomic statuses. We will use univariate and multivariate analysis to explore the relationships between type of EMS transport, socioeconomic factors, and LVO stroke outcomes. We will use geographic information systems and spatial analysis to examine the complex movements of patients in time and space. To detect an 8% difference between groups, with a 3:1 patient ratio of primary to secondary transports, 95% confidence and 80% power, we will need approximately 1600 patients. The primary outcome is the patients with modified Rankin Scale (mRS) ≤ 2 at 90 days. Subgroup analyses include patients who receive intravenous thrombolysis and duration of stroke systems. Secondary analyses include socioeconomic factors associated with poor outcomes after LVO stroke. DISCUSSION: Using the data obtained from the OPUS-REACH registry, we will develop evidence based algorithms for prehospital transport of LVO stroke patients. Unlike prior research, the OPUS-REACH registry contains patient-level data spanning from EMS dispatch to ninety day functional outcomes. We expect that we will find modifiable factors and socioeconomic disparities associated with poor outcomes in LVO stroke. OPUS-REACH with its breadth of locations, detailed patient records, and multidisciplinary researchers will design the optimal prehospital stroke system of care for LVO stroke patients.
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Arteriopatias Oclusivas , Isquemia Encefálica , Serviços Médicos de Emergência , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Arteriopatias Oclusivas/terapia , Isquemia Encefálica/diagnóstico , Humanos , Sistema de Registros , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapiaRESUMO
Overexpression of Axl, a TAM-family receptor tyrosine kinase, plays key roles in the formation, growth, and spread of tumors as well as resistance to targeted therapies and chemotherapies. We identified novel llama VHHs against human Axl using multiple complementary phage display selection strategies and characterized a subset of high-affinity VHHs. The VHHs targeted multiple sites in Ig-like domains 1 and 2 of the Axl extracellular domain, including an immunodominant epitope overlapping the site of Gas6 interaction and two additional non-Gas6 competitive epitopes recognized by murine monoclonal antibodies. Only a subset of VHHs cross-reacted with cynomolgus monkey Axl and none recognized mouse Axl. As fusions to human IgG1 Fc, VHH-Fcs bound Axl+ tumor cell lines and mertansine-loaded VHH-Fcs were cytotoxic in vitro against Axl+ cells in proportion to their binding affinities. Engineered biparatopic VHH-VHH heterodimers bound Axl avidly, and a subset of molecules showed dramatically enhanced association rates indicative of intramolecular binding. These VHHs may have applications as modular elements of biologic drugs such as antibody-drug conjugates.
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Afinidade de Anticorpos/imunologia , Receptores Proteína Tirosina Quinases/imunologia , Anticorpos de Domínio Único/imunologia , Animais , Células CHO , Camelídeos Americanos , Morte Celular , Linhagem Celular Tumoral , Cricetulus , Células HEK293 , Humanos , Cadeias Pesadas de Imunoglobulinas/imunologia , Cinética , Ligação Proteica , Domínios Proteicos , Multimerização Proteica , Receptores Proteína Tirosina Quinases/química , Proteínas Recombinantes de Fusão/metabolismoRESUMO
PURPOSE: Cutaneous T-cell lymphoma (CTCL) is a rare type of non-Hodgkin lymphoma. Previous studies have reported geographic clustering of CTCL based on the residence at the time of diagnosis. We explore geographic clustering of CTCL using both the residence at the time of diagnosis and past residences using data from the New Jersey State Cancer Registry. METHODS: CTCL cases (n = 1,163) diagnosed between 2006-2014 were matched to colon cancer controls (n = 17,049) on sex, age, race/ethnicity, and birth year. Jacquez's Q-Statistic was used to identify temporal clustering of cases compared to controls. Geographic clustering was assessed using the Bernoulli-based scan-statistic to compare cases to controls, and the Poisson-based scan-statisic to compare the observed number of cases to the number expected based on the general population. Significant clusters (p < 0.05) were mapped, and standard incidence ratios (SIR) reported. We adjusted for diagnosis year, sex, and age. RESULTS: The Q-statistic identified significant temporal clustering of cases based on past residences in the study area from 1992 to 2002. A cluster was detected in 1992 in Bergen County in northern New Jersey based on the Bernoulli (1992 SIR 1.84) and Poisson (1992 SIR 1.86) scan-statistics. Using the Poisson scan-statistic with the diagnosis location, we found evidence of an elevated risk in this same area, but the results were not statistically significant. CONCLUSION: There is evidence of geographic clustering of CTCL cases in New Jersey based on past residences. Additional studies are necessary to understand the possible reasons for the excess of CTCL cases living in this specific area some 8-14 years prior to diagnosis.
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Linfoma Cutâneo de Células T , Neoplasias Cutâneas , Análise por Conglomerados , Humanos , Incidência , Linfoma Cutâneo de Células T/diagnóstico , Linfoma Cutâneo de Células T/epidemiologia , New Jersey/epidemiologia , Neoplasias Cutâneas/epidemiologiaRESUMO
Homodimeric antibodies devoid of light chains have evolved multiple times through convergent evolution, yet their specific immunological functions remain poorly understood. We survey the molecular and structural features of these antibodies, their immunological functions in host defense, and reflect on the long-standing question of the evolutionary forces driving their emergence.
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Anticorpos/imunologia , Evolução Molecular , Cadeias Pesadas de Imunoglobulinas/imunologia , Animais , HumanosRESUMO
Prolonged serum half-life is required for the efficacy of most protein therapeutics. One strategy for half-life extension is to exploit the long circulating half-life of serum albumin by incorporating a binding moiety that recognizes albumin. Here, we describe camelid single-domain antibodies (VH Hs) that bind the serum albumins of multiple species with moderate to high affinity at both neutral and endosomal pH and significantly extend the serum half-lives of multiple proteins in rats from minutes to days. We serendipitously identified an additional VH H (M75) that is naturally pH-sensitive: at endosomal pH, binding affinity for human serum albumin (HSA) was dramatically weakened and binding to rat serum albumin (RSA) was undetectable. Domain mapping revealed that M75 bound to HSA domain 1 and 2. Moreover, alanine scanning of HSA His residues suggested a critical role for His247, located in HSA domain 2, in M75 binding and its pH dependence. Isothermal titration calorimetry experiments were suggestive of proton-linked binding of M75 to HSA, with differing binding enthalpies observed for full-length HSA and an HSA domain 1-domain 2 fusion protein in which surface-exposed His residues were substituted with Ala. M75 conferred moderate half-life extension in rats, from minutes to hours, likely due to rapid dissociation from RSA during FcRn-mediated endosomal recycling in tandem with albumin conformational changes induced by M75 binding that prevented interaction with FcRn. Humanized VH Hs maintained in vivo half-life extension capabilities. These VH Hs represent a new set of tools for extending protein therapeutic half-life and one (M75) demonstrates a unique pH-sensitive binding interaction that can be exploited to achieve modest in vivo half-life.
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Produtos Biológicos/metabolismo , Albumina Sérica/metabolismo , Animais , Linhagem Celular , Endossomos/metabolismo , Células HEK293 , Meia-Vida , Humanos , Concentração de Íons de Hidrogênio , Masculino , Ligação Proteica/fisiologia , Ratos , Ratos WistarRESUMO
Multispecific antibodies that bridge immune effector and tumor cells have shown promising preclinical and clinical efficacies. Here, we isolated and characterized novel llama single-domain antibodies (sdAbs) against CD16. One sdAb, NRC-sdAb048, bound recombinant human and cynomolgus monkey CD16 ectodomains with equivalent affinity (KD: 1 nM) but did not recognize murine CD16. Binding was similar for human CD16a expressed on NK cells and CD16b (NA2) expressed on neutrophils but dramatically weaker (KD: â¼6 µM) for the CD16b (NA1) allotype. The sdAb stained primary human peripheral blood NK cells. Irrespective of fusion orientation and linker length, bispecific sdAb-sdAb and sdAb-scFv dimers (anti-CD16/EGFR, anti-CD16/HER2, and anti-CD16/CD19) retained full binding affinity for each target, coengaged both antigens simultaneously, elicited ADCC against target antigen-expressing tumor cells in a reporter bioassay, and triggered target-specific activation and degranulation of primary NK cells as measured via interferon-γ and CD107a expression. These molecules may have applications in cancer immunotherapy.
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Anticorpos Biespecíficos/metabolismo , Células Matadoras Naturais/transplante , Neoplasias/terapia , Proteínas Recombinantes de Fusão/metabolismo , Anticorpos de Domínio Único/metabolismo , Animais , Anticorpos Biespecíficos/genética , Citotoxicidade Celular Dependente de Anticorpos , Antígenos de Neoplasias/metabolismo , Bioensaio , Camelídeos Americanos , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/genética , Humanos , Imunoterapia/métodos , Células Jurkat , Células Matadoras Naturais/metabolismo , Macaca fascicularis , Camundongos , Neoplasias/imunologia , Cultura Primária de Células , Domínios Proteicos/genética , Receptores de IgG/antagonistas & inibidores , Receptores de IgG/genética , Proteínas Recombinantes de Fusão/genética , Anticorpos de Domínio Único/genéticaRESUMO
Pseudomonas aeruginosa is an opportunistic pathogen that is inherently resistant to many antibiotics and represents an increasing threat due to the emergence of drug-resistant strains. There is a pressing need to develop innovative antimicrobials against this pathogen. In this study, we identified the O-specific antigen (OSA) of P. aeruginosa serotype O6 as a novel target for therapeutic intervention. Binding of monoclonal antibodies and antigen-binding fragments therefrom to O6 OSA leads to rapid outer membrane destabilization and inhibition of cell growth. The antimicrobial effect correlated directly with antibody affinity. Antibody binding to the O antigen of a second lipopolysaccharide (LPS) type present in P. aeruginosa or to the LPS core did not affect cell viability. Atomic force microscopy showed that antibody binding to OSA resulted in early flagellum loss, formation of membrane blebs, and eventually complete outer membrane loss. We hypothesize that antibody binding to OSA disrupts a key interaction in the P. aeruginosa outer membrane.
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Anticorpos Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Membrana Externa Bacteriana/patologia , Antígenos O/imunologia , Pseudomonas aeruginosa/imunologia , Afinidade de Anticorpos/imunologia , Flagelos/fisiologia , Lipopolissacarídeos/imunologia , Microscopia de Força Atômica , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/crescimento & desenvolvimentoRESUMO
PURPOSE: A life course perspective to cancer incidence is important for understanding effects of the environment during early life on later cancer risk. We assessed spatial clusters of cancer incidence based on early life location defined as 1940 US Census Enumeration District (ED). METHODS: A cohort of 260,585 individuals aged 0-40 years in 1940 was selected. Individuals were followed from 1940 to cancer diagnosis, death, or last residence in Utah. We geocoded ED centroids in Utah for the 1940 Census. Spatial scan statistics with purely spatial elliptic scanning window were used to identify spatial clusters of EDs with excess cancer rates across 26 cancer types, assuming a discrete Poisson model. RESULTS: Cancer was diagnosed in 66,904 (25.67%) individuals during follow-up across 892 EDs. Average follow-up was 50.9 years. We detected 15 clusters of excess risk for bladder, breast, cervix, colon, lung, melanoma, oral, ovary, prostate, and soft tissue cancers. An urban area had dense overlap of multiple cancer types, including two EDs at increased risk for five cancer types each. CONCLUSIONS: Early environments may contribute to cancer risk later in life. Life course perspectives applied to the study of cancer incidence can provide insights for increasing understanding of cancer etiology.
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Neoplasias/epidemiologia , Adolescente , Adulto , Censos , Criança , Pré-Escolar , Análise por Conglomerados , Estudos de Coortes , Meio Ambiente , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Neoplasias/mortalidade , Sistema de Registros , Utah/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Residential histories linked to cancer registry data provide new opportunities to examine cancer outcomes by neighborhood socioeconomic status (SES). We examined differences in regional stage colon cancer survival estimates comparing models using a single neighborhood SES at diagnosis to models using neighborhood SES from residential histories. METHODS: We linked regional stage colon cancers from the New Jersey State Cancer Registry diagnosed from 2006 to 2011 to LexisNexis administrative data to obtain residential histories. We defined neighborhood SES as census tract poverty based on location at diagnosis and across the follow-up period through 31 December 2016 based on residential histories (average, time-weighted average, time-varying). Using Cox proportional hazards regression, we estimated associations between colon cancer and census tract poverty measurements (continuous and categorical), adjusted for age, sex, race/ethnicity, regional substage, and mover status. RESULTS: Sixty-five percent of the sample was nonmovers (one census tract); 35% (movers) changed tract at least once. Cases from tracts with >20% poverty changed residential tracts more often (42%) than cases from tracts with <5% poverty (32%). Hazard ratios (HRs) were generally similar in strength and direction across census tract poverty measurements. In time-varying models, cases in the highest poverty category (>20%) had a 30% higher risk of regional stage colon cancer death than cases in the lowest category (<5%) (95% confidence interval [CI] = 1.04, 1.63). CONCLUSION: Residential changes after regional stage colon cancer diagnosis may be associated with a higher risk of colon cancer death among cases in high-poverty areas. This has important implications for postdiagnostic access to care for treatment and follow-up surveillance. See video abstract: http://links.lww.com/EDE/B705.
Assuntos
Neoplasias do Colo , Disparidades nos Níveis de Saúde , Áreas de Pobreza , Características de Residência , Neoplasias do Colo/epidemiologia , Humanos , New Jersey/epidemiologia , Características de Residência/estatística & dados numéricos , Fatores Socioeconômicos , Análise de SobrevidaRESUMO
Objectives. To evaluate changes in licensed tobacco retailers and retailer density 5 years before and 3 years after novel tobacco retailer licensing regulations were implemented in a large, urban area.Methods. We used administrative tobacco license data (n = 23 806 licenses, 2012-2019) to calculate (1) annual retailer density by district (n = 18), (2) density by district and school income status, and (3) retailers within 500 feet of schools (n = 673) before and after regulations.Results. Observed tobacco retailer density declined by 20.3% (from 1.97 to 1.57 per 1000 daytime residents) 3 years after regulation implementation. Regression results showed a decline in the trend of retailers per 1000 daytime population (b = -0.19; 95% confidence interval[CI] = -0.23, -0.14) that was modestly but significantly greater in low-income districts (interaction b = -0.18; 95% CI = -0.25, -0.11) and a 12% decline in the rates of retailers near schools (rate ratio = 0.88; 95% CI = 0.85, 0.92) following implementation of the regulations. We did not observe similar density changes in comparable cities.Conclusions. Tobacco retailer licensing strategies can be an effective policy approach to reduce the availability of tobacco and tobacco marketing, lessen socioeconomic disparities in tobacco retailer density, and decrease the number of tobacco outlets near schools.
Assuntos
Comércio/legislação & jurisprudência , Licenciamento/legislação & jurisprudência , Produtos do Tabaco/legislação & jurisprudência , Comércio/estatística & dados numéricos , Philadelphia , Instituições Acadêmicas , Fatores Socioeconômicos , Produtos do Tabaco/estatística & dados numéricosRESUMO
Up-regulation of epidermal growth factor receptor (EGFR) is a hallmark of many solid tumors, and inhibition of EGFR signaling by small molecules and antibodies has clear clinical benefit. Here, we report the isolation and functional characterization of novel camelid single-domain antibodies (sdAbs or VHHs) directed against human EGFR. The source of these VHHs was a llama immunized with cDNA encoding human EGFR ectodomain alone (no protein or cell boost), which is notable in that genetic immunization of large, outbred animals is generally poorly effective. The VHHs targeted multiple sites on the receptor's surface with high affinity (KD range: 1-40â nM), including one epitope overlapping that of cetuximab, several epitopes conserved in the cynomolgus EGFR orthologue, and at least one epitope conserved in the mouse EGFR orthologue. Interestingly, despite their generation against human EGFR expressed from cDNA by llama cells in vivo (presumably in native conformation), the VHHs exhibited wide and epitope-dependent variation in their apparent affinities for native EGFR displayed on tumor cell lines. As fusions to human IgG1 Fc, one of the VHH-Fcs inhibited EGFR signaling induced by EGF binding with a potency similar to that of cetuximab (IC50: â¼30â nM). Thus, DNA immunization elicited high-affinity, functional sdAbs that were vastly superior to those previously isolated by our group through protein immunization.