The Impact of an Interactive Unconscious Bias Training on Perioperative Learners.

Background: Providers' unconscious biases reinforce health disparities through negative direct patient care and interactions with colleagues. Objective: We created a workshop grounded in Critical Race Theory and the importance of different intersectionalities to improve medical trainees' self-assessment of their implicit biases in curated facilitated spaces. Methods: A total of 44 UCSF first-year clinical anesthesiology residents (CA-1) (95% response rate) and 23 surgery residents in their research year (77% response rate) participated in this workshop over 4 separate sessions in September 2020 and 2021. Quantitative data from a pre-/post-workshop survey was analyzed via a paired t test to evaluate our workshop's effectiveness. Feedback on efficacy was obtained by coding themes from our survey's open-ended questions. Results: The workshop was evaluated positively by a total of 65 of 67 participants in the post-workshop survey. On a 5-point Likert scale, participants self-reported they agreed that their unconscious biases affect their clinical interactions from a pre-workshop mean of 3.3 (SD ± 1.32) to a post-workshop mean of 3.9 (SD ± 0.87, P = .008). Conclusion: Our findings suggest that this workshop was effective for perioperative residents and can be extrapolated to all residents by tailoring the workshop to their respective work environments.

Tunable and Modular miRNA Classifier through Indirect Associative Toehold Strand Displacement.

The programmability of nucleic acids allows detection devices with complex behaviors to be designed de novo. While highly specific, these high-order circuits are usually sequence constrained, making their adaptability toward biological targets challenging. Here, we devise a new strategy called indirect associative strand displacement to decouple sequence constraints between miRNA inputs and de novo strand displacement circuits. By splitting circuit inputs into their toehold and branch migration regions and controlling their association through a docking strand, we demonstrate how any miRNA sequence can be interfaced with synthetic DNA circuits, including catalytic hairpin assembly and a four-input classifier.

Bispecific antibodies for immune cell retargeting against cancer.

INTRODUCTION: Following the approval of the T cell engaging bispecific antibody blinatumomab, immune cell retargeting with bispecific or multispecific antibodies has emerged as a promising cancer immunotherapy strategy, offering alternative mechanisms compared to immune checkpoint blockade. As we gain more understanding of the complex tumor microenvironment, rules and design principles have started to take shape on how to best harness the immune system to achieve optimal anti-tumor activities. AREAS COVERED: In the present review, we aim to summarize the most recent advances and challenges in using bispecific antibodies for immune cell retargeting and to provide insights into various aspects of antibody engineering. Discussed herein are studies that highlight the importance of considering antibody engineering parameters, such as binding epitope, affinity, valency, and geometry to maximize the potency and mitigate the toxicity of T cell engagers. Beyond T cell engaging bispecifics, other bispecifics designed to recruit the innate immune system are also covered. EXPERT OPINION: Diverse and innovative molecular designs of bispecific/multispecific antibodies have the potential to enhance the efficacy and safety of immune cell retargeting for the treatment of cancer. Whether or not clinical data support these different hypotheses, especially in solid tumor settings, remains to be seen.

Controlling metabolic flux by toehold-mediated strand displacement.

To maximize desired products in engineered cellular factories it is often necessary to optimize metabolic flux. While a number of works have focused on metabolic pathway enhancement through genetic regulators and synthetic scaffolds, these approaches require time-intensive design and optimization with limited versatility and capacity for scale-up. Recently, nucleic-acid nanotechnology has emerged as an encouraging approach to overcome these limitations and create systems for modular programmable control of metabolic flux. Using toehold-mediated strand displacement (TMSD), nucleic acid constructs can be made into dynamic devices that recognize specific biomolecular triggers for conditional control of gene regulation as well as design of dynamic synthetic scaffolds. This review will consider the various approaches that have been used thus far to control metabolic flux using toehold-gated devices.

Synthetic biology approaches for targeted protein degradation.

Protein degradation is an effective native mechanism used in modulating intracellular information, and thus it plays an essential role in maintaining cellular homeostasis. Repurposing native protein degradation in a synthetic context is gaining attention as a new strategy to manipulate cellular behavior rapidly for a wide range of applications including disease detection and therapy. This review examines the native mechanisms and machineries by which mammalian cells degrade their own proteins including the sequence of events from identifying a candidate for degradation to the protein's destruction. Next, it explores engineering efforts to degrade both exogenous and native proteins with high specificity and control by targeting proteins into the degradation cascade. A complete understanding of design rules with an ability to use cellular information as signals will allow control over the cellular behavior in a well-defined manner.

Dynamic protein assembly by programmable DNA strand displacement.

Inspired by the remarkable ability of natural protein switches to sense and respond to a wide range of environmental queues, here we report a strategy to engineer synthetic protein switches by using DNA strand displacement to dynamically organize proteins with highly diverse and complex logic gate architectures. We show that DNA strand displacement can be used to dynamically control the spatial proximity and the corresponding fluorescence resonance energy transfer between two fluorescent proteins. Performing Boolean logic operations enabled the explicit control of protein proximity using multi-input, reversible and amplification architectures. We further demonstrate the power of this technology beyond sensing by achieving dynamic control of an enzyme cascade. Finally, we establish the utility of the approach as a synthetic computing platform that drives the dynamic reconstitution of a split enzyme for targeted prodrug activation based on the sensing of cancer-specific miRNAs.

Synthetic scaffolds for pathway enhancement.

Controlling local concentrations of reactants, intermediates, and enzymes in synthetic pathways is critical for achieving satisfactory productivity of any desired products. An emerging approach to exert control over local concentrations is the use of synthetic biomolecular scaffolds to co-localize key molecules of synthetic pathways. These scaffolds bring the key molecules into close proximity by recruiting pathway enzymes via ligand binding and/or physically sequestrating enzymes and metabolites into isolated compartments. Novel scaffolds made of proteins, nucleic acids, and micro-compartments with increasingly complex architecture have recently been explored and applied to a variety of pathways, with varying degrees of success. Despite these strides, precise assembly of synthetic scaffolds remains a difficult task, particularly in vivo, where interactions both intended and unexpected can lead to unpredictable results. Additionally, because heterologous enzymes often have lowered activities in their new hosts, an ideal scaffold should provide a flexible platform that can adapt to kinetic imbalances in different contexts. In this review, we discuss some of the notable advances in the creation of these synthetic scaffolds and highlight the current challenges in their application.