Biology subjects

Worthen, G. S.

Publications and source records attributed to Worthen, G. S..

7 recordsLinked to original sources

bioRxiv2025

Microengineered transplantation of human solid tumors for in vitro studies of CAR T immunotherapy

Treatment of solid malignancies using chimeric antigen receptor (CAR) T cells remains a significant challenge, but current efforts to advance this therapy are challenged by our limited capacity to probe and understand cancer-immune interactions in human solid tumors. Here, we present a microengineered platform for in vitro modeling of malignant solid tumors during CAR T therapy. This system makes it possible to vascularize human tumor explants and perfuse them with blood-borne immune cells in a controlled manner. We first present a microphysiological model of human lung adenocarcinomas infused with CAR-T cells and show how this system can be used to simulate, visualize, and interrogate tumor-directed trafficking and effector function of CAR T cells. We then demonstrate the proof-of-principle of testing a chemokine-directed CAR T cell engineering strategy in a model of malignant pleural mesothelioma and validating our in vitro assessment using a matching in vivo mouse model. Finally, we describe a potential therapeutic target discovered by single-cell RNA sequencing that can be pharmacologically modulated to increase the efficacy of CAR T cells for lung adenocarcinoma, for which we also present specific biomarkers identified by global metabolomics analysis. We believe that the bioengineering principle demonstrated here will make important contributions to developing new capabilities for preclinical studies of adoptive cell therapies for cancer and other complex diseases.

bioengineering↗

bioRxiv2022

Nanoparticle-induced augmentation of neutrophils' phagocytosis of bacteria

Despite the power of antibiotics, bacterial infections remain a major killer, due to antibiotic resistance and hosts with dysregulated immune systems. We and others have been developing drug-loaded nanoparticles that home to the sites of infection and inflammation via engineered tropism for neutrophils, the first-responder leukocytes in bacterial infections. Here, we examined how a member of a broad class of neutrophil-tropic nanoparticles affects neutrophil behavior, specifically questioning whether the nanoparticles attenuate an important function, bacterial phagocytosis. We found these nanoparticles actually augment phagocytosis of non-opsonized bacteria, increasing it by ~50%. We showed this augmentation of phagocytosis is likely co-opting an evolved response, as opsonized bacteria also augment phagocytosis of non-opsonized bacteria. Enhancing phagocytosis of non-opsonized bacteria may prove particularly beneficial in two clinical situations: in hypocomplementemic patients (meaning low levels of the main bacterial opsonins, complement proteins, seen in conditions such as neonatal sepsis and liver failure) or for bacteria that are largely resistant to complement opsonization (e.g., Neisseria). Additionally, we observe that; a) prior treatment with bacteria augments neutrophil uptake of neutrophil-tropic nanoparticles; b) neutrophil-tropic nanoparticles colocalize with bacteria inside of neutrophils. The observation that neutrophil-tropic nanoparticles enhance neutrophil phagocytosis and localize with bacteria inside neutrophils suggests that these nanoparticles will serve as useful carriers for drugs to ameliorate bacterial diseases.

immunology↗

bioRxiv2021

Circadian regulation of lung repair and regeneration

Optimal lung repair and regeneration is essential for recovery from viral infections such as that induced by influenza A virus (IAV). We have previously demonstrated that lung inflammation induced by IAV is under circadian control. However, it is not known if the circadian clock exerts its influence on lung repair and regenerative processes independent of acute inflammation from IAV. Here, we demonstrate for the first time that lung organoids have a functional clock as they mature and that the absence of an intact circadian clock impairs regenerative capacity. Using several models of circadian disruption, we show that with the absence of an intact clock lung proliferation is disrupted. Further, we find that the circadian clock acts through direct control of the Wnt/{beta}-catenin pathway. We speculate, that adding the circadian dimension to the critical process of lung repair and regeneration will lead to novel therapies and improve outcomes. Finally, we use data from UK Biobank to demonstrate at the population level, the role of poor circadian rhythms in mediating negative outcomes following lung infection.

cell biology↗

bioRxiv2021

Type II alveolar cells with constitutive expression of MHCII and limited antigen presentation capacity contribute to improved respiratory viral disease outcomes

Type II alveolar cells (AT2s) are critical for basic respiratory homeostasis and tissue repair after lung injury. Prior studies indicate that AT2s also express major histocompatibility complex II (MHCII) molecules, but how MHCII expression by AT2s is regulated and how it contributes to host defense remain unclear. Here we show that AT2s express high levels of MHCII independent of conventional inflammatory stimuli, and that selective loss of MHCII from AT2s in mice results in the worsening of respiratory virus disease following influenza and Sendai virus infections. We also find that AT2s exhibit MHCII presentation capacity that is substantially limited in comparison to professional antigen presenting cells. The combination of constitutive MHCII expression and restrained presentation may position AT2s to contribute to lung adaptive immune responses in a measured fashion, without over-amplifying damaging inflammation.

immunology↗

bioRxiv2021

Red Blood Cells Function as DNA Sensors

Erythrocytes have long been mistaken as exclusively inert oxygen carriers lacking immune function. Here we show that red blood cells (RBCs) serve as immune sensors through surface expression of the nucleic acid-sensing toll-like receptor 9 (TLR9), a classically endosomal receptor that initiates immune responses following the detection of unmethylated CpG motifs present in pathogen and mitochondrial DNA. Mammalian RBCs express TLR9 on their surface and bind CpG-containing bacterial, malarial, and mitochondrial DNA. Erythrocyte-bound CpG DNA increases during infection, and CpG-carrying RBCs trigger accelerated erythrophagocytosis and innate immune activation characterized by RBC-TLR9 dependent local and systemic cytokine production. Thus, RBC nucleic acid detection and capture regulates red cell clearance and immune responses and provides evidence for RBCs as innate immune sentinels during pathologic states. One Sentence SummaryThe ability of RBCs to detect and bind cell-free nucleic acids contributes to immunity during acute inflammatory states.

immunology↗

bioRxiv2020

Supramolecular Organization Predicts Protein Nanoparticle Delivery to Neutrophils for Acute Lung Inflammation Diagnosis and Treatment

Acute lung inflammation has severe morbidity, as seen in COVID-19 patients. Lung inflammation is accompanied or led by massive accumulation of neutrophils in pulmonary capillaries ("margination"). We sought to identify nanostructural properties that predispose nanoparticles to accumulate in pulmonary marginated neutrophils, and therefore to target severely inflamed lungs. We designed a library of nanoparticles and conducted an in vivo screen of biodistributions in naive mice and mice treated with lipopolysaccharides. We found that supramolecular organization of protein in nanoparticles predicts uptake in inflamed lungs. Specifically, nanoparticles with agglutinated protein (NAPs) efficiently home to pulmonary neutrophils, while protein nanoparticles with symmetric structure (e.g. viral capsids) are ignored by pulmonary neutrophils. We validated this finding by engineering protein-conjugated liposomes that recapitulate NAP targeting to neutrophils in inflamed lungs. We show that NAPs can diagnose acute lung injury in SPECT imaging and that NAP-like liposomes can mitigate neutrophil extravasation and pulmonary edema arising in lung inflammation. Finally, we demonstrate that ischemic ex vivo human lungs selectively take up NAPs, illustrating translational potential. This work demonstrates that structure-dependent interactions with neutrophils can dramatically alter the biodistribution of nanoparticles, and NAPs have significant potential in detecting and treating respiratory conditions arising from injury or infections.

bioengineering↗

bioRxiv2018

Using selective lung injury to improve murine models of spatially heterogeneous lung diseases

Many lung diseases, such as acute respiratory distress syndrome (ARDS), display significant regional heterogeneity, with patches of severely injured tissue adjacent to apparently healthy tissue. Current mouse models that aim to mimic ARDS generally produce diffuse injuries that cannot reproducibly generate ARDSs regional heterogeneity. This deficiency prevents the evaluation of how well therapeutic agents reach the most injured regions, and precludes many regenerative medicine studies, since it is not possible to know which apparently healing regions suffered severe injury initially. Finally, these diffuse injury models must be mild to allow for survival, as their diffuse nature does not allow for residual healthy lung to keep an animal alive long enough for many drug and regenerative medicine studies. To solve all of these deficiencies of current animal models, we have created a simple and reproducible technique to selectively induce lung injury in specific areas of the lung. Our technique, catheter-in-catheter selective lung injury (CICSLI), involves guiding an inner catheter to a particular area of the lung and delivering an injurious agent mixed with nanoparticles (fluorescently and/or radioactively labeled) that can be used to track the location and extent of where the initial injury was, days later. Further, we demonstrate that CICSLI can produce a more severe injury than diffuse models, yet has much higher survival since CICSLI intentionally leaves undamaged lung regions. Collectively, these attributes of CICSLI will allow better study of how drugs act within heterogeneous lung pathologies and how regeneration occurs in severely damaged lung tissue, thereby aiding the development of new therapies for ARDS and other lung diseases.

pharmacology and toxicology↗