Biology subjects

Miller, B.

Publications and source records attributed to Miller, B..

At least 19 recordsLinked to original sources

bioRxiv2026

Large-scale cerebrospinal fluid proteomics identifies diagnostic biomarker candidates across the clinico-pathological continuum of frontotemporal lobar degeneration

Frontotemporal lobar degeneration (FTLD), predominantly comprised of tau and TDP-43 proteinopathies, is a common cause of early-onset dementia. Biomarkers that reliably classify FTLD subtypes are limited, thereby hindering in-vivo diagnosis and clinical trial stratification. We conducted large-scale, multi-platform cerebrospinal fluid proteomics in 566 individuals, including 274 FTLD-spectrum (48 autopsy-confirmed FTLD-TDP, 90 autopsy-confirmed FTLD-tau), 171 Alzheimers disease, and 95 controls. In neuropathological subtype contrasts, elevated matrix metalloproteinase MMP10 classified Picks disease (PiD) versus other subtypes with near-perfect accuracy across proteomic platforms. We further validated CSF MMP10 as a potential PiD diagnostic biomarker via a targeted immunoassay in an independent, autopsy-confirmed FTLD cohort. Post-synaptic proteins HOMER1 and DLG4 exhibited elevations across FTLD-TDP subtypes (A, B, and C) versus FTLD-tau. Network analysis identified RNA metabolism and pro-inflammatory signatures in FTLD-TDP, and cytoskeletal and heat shock signatures in progressive supranuclear palsy. These findings reveal candidate diagnostic biomarkers and proteomic pathways underlying FTLD clinico-pathological heterogeneity.

neuroscience↗

bioRxiv2026

Plaque-associated oligodendrocyte proteostatic failure underlies myelin loss in Alzheimers disease

Alzheimers disease (AD) features amyloid-{beta} plaques and tau pathology, yet the mechanism underlying early and clinically significant myelin loss remains unresolved. Here, we report human iPSC-derived forebrain organoids with doxycycline-inducible expression of SOX10, OLIG2, and NKX6-2 (SON), which generate robust, mature oligodendrocytes and compact myelin in vitro and in vivo. Introducing amyloid precursor protein (APP) pathogenic mutations produces extracellular amyloid-{beta} plaques and phosphorylated tau, accompanied by reduced myelin basic protein (MBP) expression and disrupted myelin ultrastructure. Single-cell and spatial transcriptomics combined with amyloid plaque imaging reveal that oligodendrocytes in plaque-dense regions show pathological changes in calcium signaling, immune activation, lipid remodeling, and protein catabolic pathways. Notably, MBP protein is reduced despite elevated myelin-related transcription, suggesting plaque-induced degradation of myelin proteins. Consistent with this, proteasomal inhibition restores MBP protein levels and improves compact myelin ultrastructure in AD organoids. In human AD brain tissue, protein catabolic pathways are similarly upregulated with increasing plaque density. Together, these findings identify plaque-associated oligodendrocyte proteostatic failure as a candidate mechanism of myelin loss and a potential therapeutic pathway in AD.

neuroscience↗

bioRxiv2026

Transient MYC Mimicking the Exercise Response Orchestrates Multifaceted Skeletal Muscle Adaptations

Despite decades of study, MYCs physiological role in adult tissues remains obscured by the models used to investigate it. Most work relies almost exclusively on chronic or constitutive MYC induction that recapitulates the sustained activity found in tumorigenesis and expectedly produces pathological outcomes. What has gone largely untested is how MYC operates when induced in a controlled and physiologically relevant manner, as it is during adaptive processes such as exercise. Using a recombination-independent strategy in adult skeletal muscle, transient MYC bursts drive coordinated hypertrophic-metabolic reprogramming followed by a shift in myosin fiber type, recapitulating adaptations characteristic of concurrent endurance and resistance training. A single pleiotropic transcription factor governing several aspects of muscle health reframes perspectives on a gene understood almost entirely in the context of pathology. We uncover a previously unrecognized muscle-specific role for MYC in controlling muscle cell composition and present a multi-timepoint multi-omic resource for interrogating MYC: data.myoanalytics.com/study/myc_transient/gene.

Cell Biology↗

bioRxiv2026

Cell autonomous inflammation in VEXAS is mediated by cGAS-STING

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) is a severe adult-onset inflammatory disease caused by somatic mutations that reduce cytoplasmic activity of UBA1, the primary initiating enzyme for ubiquitylation. How this hypomorphic state drives cell-intrinsic immune activation in mature myeloid cells is unknown. Using unbiased multi-omic, biochemical, and cell biological analyses of model systems and patient-derived cells, we show that loss of cytoplasmic UBA1 activity convergently disrupts endoplasmic reticulum- associated degradation (ERAD) and mitochondrial homeostasis. ERAD failure arises from preferential under-charging of ERAD E2 enzymes, explaining hallmark VEXAS features, including ER-derived vacuoles and unfolded protein response activation, and promotes accumulation of the ERAD substrate STING. Simultaneously, mitochondrial dysfunction drives cytosolic leakage of mitochondrial DNA, inducing cGAS-dependent STING signaling and inflammatory cytokine production. STING inhibition or reversal of mitochondrial DNA leakage resolves multi-cytokine inflammation in VEXAS models and patient myeloid cells, establishing the cGAS-STING pathway as a therapeutically actionable vulnerability.

genetics↗

bioRxiv2026

BioDCASE: Using data challenges to make community advances in computational bioacoustics

Computational bioacoustics has seen significant advances in recent decades. However, the rate of insights from automated analysis of bioacoustic audio lags behind our rate of collecting the data - due to key capacity constraints in data annotation and bioacoustic algorithm development. Gaps in analysis methodology persist: not because they are intractable, but because of resource limitations in the bioacoustics community. To bridge these gaps, we advocate the open science method of data challenges, structured as public contests. We conducted a bioacoustics data challenge named BioDCASE, within the format of an existing event (DCASE). In this work we report on the procedures needed to select and then conduct useful bioacoustics data challenges. We consider aspects of task design such as dataset curation, annotation, and evaluation metrics. We report the three tasks included in BioDCASE 2025 and the resulting progress made. Based on this we make recommendations for open community initiatives in computational bioacoustics.

animal behavior and cognition↗

bioRxiv2026

Autolab HBH: A Rapid Hyperbaric Heating Device for Streamlined, PCR-Ready Sample Preparation Across Diverse Biological Matrices and Organisms

Traditional nucleic acid extraction methods are costly, lengthy, and highly variable depending on the complexity of the sample matrix or the organism of interest. Workflows may exceed twenty steps, require separate kits for RNA and DNA, and demand expensive instrumentation, creating barriers to both speed and scalability. The AutolabTM HBH system addresses these limitations by using hyperbaric heating (HBH) to achieve temperatures above 100 {degrees}C in a sealed, pressurized environment through induction heating, enabling rapid lysis of diverse organisms and neutralization of macromolecular PCR inhibitors within minutes. The combination of extreme heat and HBH-optimized lyophilized reagents rapidly inactivates nucleases while preserving free nucleic acids. The workflow is streamlined to two steps: heating up to 1 mL of sample in the proprietary HBH bullet, followed by a brief centrifugation to pellet additives. The resulting supernatant is immediately compatible with real-time reverse transcription polymerase chain reaction (RT-PCR) and other downstream molecular assays. Here, we evaluate the systems broad compatibility with diverse sample buffers, matrices, and organisms. Comparative testing was conducted alongside Qiagen extraction methods to benchmark performance.

molecular biology↗

bioRxiv2026

Physiological detection of flow states across varied gameplay workloads

Flow is a cognitive state associated with heightened and seemingly effortless behavioral performance. Pioneering research suggests flow is an optimal cognitive mode for demanding tasks but the physiological underpinnings and identification on acute timescales, particularly across task contexts, remains an active area of research. Studies have demonstrated flow experiences are ubiquitous, in that they can arise during nearly any type of activity, suggesting flow represents a fundamental mechanism of skill mastery under which sensory inputs are seamlessly coupled to the necessary motor outputs. Cognitively, flow states are accompanied by a sense of complete task immersion, feelings of control, automatic behavior, decreased self-referential thinking and anxiety, changes in the perception of time, and improved affect to the point that arduous tasks can become autotelic, or self-rewarding. As wearable sensor technology continues to advance, the identification and manipulation of cognitive states in real-time is increasingly becoming a reality, with the potential to revolutionize learning, treatment of neurological disorders, and optimize task performance in domains ranging from professional sports to industry. This study aims to capture flow states from physiological measures so that they might be identified through wearable sensors coupled to machine-learning pipelines. In this work, models are made to predict high behavioral performance across disparately varied task conditions using multimodal physiological data, and these behavioral bouts are loosely correlated to participant responses to traditional flow state survey questions.

neuroscience↗

bioRxiv2025

Deletion of the polarity protein Llgl1 impairs cardiomyocyte intercalated disc integrity and permits cell cycle activity into adulthood

BackgroundCell polarity orchestrates spatial organization within tissues influencing cellular processes such as adhesion, proliferation, and differentiation. While the role of polarity proteins is well-established in epithelial systems, their function in mammalian cardiomyocytes remains poorly understood. Global deletion of the polarity protein, Llgl1, has been shown to impair cardiac trabeculation and disrupt cardiomyocyte junctions in zebrafish. Here, we investigate the role of Llgl1 in mammalian cardiomyocyte function. MethodsWe developed a mouse model whereby Llgl1 is deleted from cardiomyocytes (Llgl1CKO) and assessed cardiomyocyte intercalated disc integrity, cell cycle activity, cardiac function, and electrophysiology. We subjected mice to myocardial infarction to test if permanent Llgl1 deletion, or inducible Llgl1 deletion in adult cardiomyocytes (Llgl1TamCKO), influences the cardiac injury response. We performed RNAsequencing and in vitro knockdown and viral overexpression experiments to delineate the mechanisms by which Llgl1 influences cardiomyocyte phenotypes. ResultsLlgl1CKO mice display disrupted intercalated disc integrity indicated by reduced protein density at cardiomyocyte junctions, associated with electrical conduction defects that manifest as ventricular arrhythmia. Furthermore, Llgl1CKO mice display enhanced cardiomyocyte cell cycle activity extending into adulthood. Llgl1CKO mice and mice whereby Llgl1 is deleted by tamoxifen induction in adulthood both show improved cardiac function and reduced scar size following myocardial infarction. Mechanistically, Llgl1 alters mechanotransduction and cell cycle pathways in the heart, and regulates proper localization of N-cadherin to the cell membrane, a process that is optimized by phosphorylation of five serine residues at the C-terminus of Llgl1. ConclusionsWe elucidate a key role for Llgl1 in establishing proper intercalated disc integrity in mammalian cardiomyocytes. Disruption of intercalated discs and mechanotransduction via Llgl1 knockout is associated with cardiac arrhythmia, elevated cell cycle activity and resistance to cardiac injury. These studies shed light on mechanisms underlying intercalated disc establishment and connect disrupted cardiomyocyte junctional integrity with enhanced cell cycle activity.

cell biology↗

bioRxiv2025

SPACE: spatially resolved multiomic analysis for high-throughput CRISPR screening in 3D models

Current spatial CRISPR screening technologies are limited by targeted readouts and high costs, restricting the scope of biological discovery. Here we present SPAtial Cell Exploration (SPACE), a spatial CRISPR screening platform that integrates whole-transcriptome profiling ([~]18,000 genes), multiplexed protein detection ([~]68 markers), and CRISPR perturbation mapping at subcellular resolution. SPACE significantly reduces whole-transcriptome profiling costs compared to sequencing methods while preserving spatial context. We demonstrate SPACE by screening 43 CRISPR knockouts (KOs) across [~]100,000 cells in hundreds of cancer-associated fibroblast (CAF)-tumor spheroids, obtaining whole-transcriptome and multiplexed protein readout from the same exact cells. SPACE revealed previously unknown regulatory mechanisms on tumor extracellular matrix (ECM) remodeling, and identified spatially-resolved ligand-receptor interactions and perturbation-specific spatial gene signatures that are not detectable with dissociation-based methods. This scalable, cost-effective platform provides a transformative framework for high-throughput spatial perturbation studies in complex tissue models.

cell biology↗

bioRxiv2025

A Dual-Readout Photonic Sensor for Simultaneous Measure-ment of Enzyme Activity and Concentration

Enzyme assays are a cornerstone of basic biology and clinical diagnosis. Typically, enzyme activity is measured, but concentration of the enzyme is also of interest, as are comparisons between concentration and activity. In these situations, separate concentration (i.e. ELISA) and activity (i.e. absorbance) assays are required to fully quantify. Here, we report a multiplex disposable photonic biosensor for simultaneous measurement of enzyme activity and concentration. Capture of the enzyme by a ring resonator-bound antibody produces a red shift in resonance, which can be referenced to a nonspecific binding control. At the same time, enzyme-mediated degradation of a ring-bound substrate produces a resonance blue shift, which can be referenced to a peptide inert to enzymatic cleavage. We tested the dual assay with human Cathepsin-L, dysfunction of which is a hallmark of several diseases, including COVID-19, kidney failure, and cancer. Both assays were found to be well-behaved analytically, with lower limits of detection of 2.0 ng*mL-1 (concentration) and 1.8 ng*mL-1 (activity), well within the range clinically relevant concentrations. Further assessment with a panel of 25 single-donor human serum samples confirmed utility of the assay in a complex, biologically relevant matrix. This approach therefore serves as a useful method for Cathepsin-L detection, and a prototype for other dual-mode photonic enzyme assays.

bioengineering↗

bioRxiv2024

A new class of penicillin-binding protein inhibitors to address drug-resistant Neisseria gonorrhoeae

{beta}-Lactams are the most widely used antibiotics for the treatment of bacterial infections because of their proven track record of safety and efficacy. However, susceptibility to {beta}-lactam antibiotics is continually eroded by resistance mechanisms. Emerging multidrug-resistant (MDR) Neisseria gonorrhoeae strains possessing altered penA alleles (encoding PBP2) pose a global health emergency as they threaten the utility of ceftriaxone, the last remaining outpatient antibiotic. Here we disclose a novel benzoxaborinine-based penicillin-binding protein inhibitor series (boro-PBPi) that is envisioned to address penA-mediated resistance while offering protection against evolution and expansion of {beta}-lactamases. Optimization of boro-PBPi led to the identification of compound 21 (VNRX-14079) that exhibits potent antibacterial activity against MDR N. gonorrhoeae achieved by high affinity binding to the PBP2 target. Boro-PBPi/PBP2 complex structures confirmed covalent interaction of the boron atom with Ser310 and the importance of the {beta}3-{beta}4 loop for improved affinity. 21 elicits bactericidal activity, a low frequency of resistance, a good safety profile, suitable pharmacokinetic properties, and in vivo efficacy in a murine infection model against ceftriaxone-resistant N. gonorrhoeae. 21 is a promising anti-gonorrhea agent poised for further advancement.

microbiology↗

bioRxiv2024

Cefepime-Taniborbactam and Ceftibuten-Ledaborbactam Maintain Activity Against KPC Variants that Lead to Ceftazidime-Avibactam Resistance

Klebsiella pneumoniae carbapenemases (KPCs) are widespread {beta}-lactamases that are a major cause of clinical non-susceptibility of Gram-negative bacteria to carbapenems and other {beta}-lactam antibiotics. Ceftazidime combined with the {beta}-lactamase inhibitor avibactam (CAZ-AVI) has been effective for treating infections by KPC-producing bacteria, but emergent KPC variants confer resistance to the combination. Taniborbactam and ledaborbactam are bicyclic boronate {beta}-lactamase inhibitors under development with cefepime and ceftibuten, respectively, to treat carbapenem-resistant bacterial infections. Here, we assessed the effects of clinically important KPC-2 and KPC-3 variants (V240G, D179Y, D179Y T243M) on the antibacterial activity of cefepime-taniborbactam (FEP-TAN) and ceftibuten-ledaborbactam (CTB-LED) and examined catalytic activity and inhibition of these variants. FEP-TAN and CTB-LED were highly active against CAZ-AVI-resistant engineered E. coli strains expressing these variants. Purified KPC variants catalyzed more efficient CAZ hydrolysis than wild-type enzymes, and D179Y-containing KPC-3 variants additionally catalyzed more efficient FEP hydrolysis than wild-type KPC-3. All KPC variants poorly hydrolyzed CTB, and D179Y-containing variants demonstrated significantly higher affinity for CAZ than FEP or CTB. Second-order rate constants (k2/K) for inhibition of D179Y-containing KPC-2 variants were significantly reduced relative to wild-type KPC-2, with AVI most impacted. K2/K was less affected for D179Y-containing KPC-3 variants, and reflected robust inhibition by TAN, LED and AVI. Together, the findings illustrate a biochemical basis for greater FEP-TAN and CTB-LED antibacterial activity in KPC variant expression backgrounds relative to CAZ-AVI, whereby the boronate inhibitors have sufficient inhibitory activity, whilst FEP and CTB are poorer substrates and bind to the variant enzymes with reduced affinity compared to CAZ.

biochemistry↗

bioRxiv2024

Efficient Generation of Human Pluripotent Stem Cells from Frozen Cord Tissue via Chemical Reprogramming

Chemical reprogramming presents an innovative approach for generating induced pluripotent stem cells (iPSCs), bypassing the genetic instability and safe concern associated with viral vector approach. We describe a novel, efficient chemical method for reprogramming human umbilical cord tissue-derived mesenchymal stem cells (MSCs) into induced pluripotent stem cells (iPSCs). Compared to previous sources like adipose tissue and skin, frozen umbilical cord tissue offers an abundant, non-invasive, long-term storable, and ethically sound cell source. Our findings not only showcase the feasibility and safety of utilizing chemical reprogramming on cells from frozen umbilical cords but also underscore its potential in regenerative medicine, especially for developing safer and more effective therapies for cardiovascular diseases.

cell biology↗

bioRxiv2024

Human chorionic gonadotropin decreases cerebral cystic encephalomalacia and parvalbumin interneuron degeneration in a pro-inflammatory model of mouse neonatal hypoxia-ischemia.

The pregnancy hormone, human chorionic gonadotropin (hCG) is an immunoregulatory and neurotrophic glycoprotein of potential clinical utility in the neonate at risk for cerebral injury. Despite its well-known role in its ability to modulate the innate immune response during pregnancy, hCG has not been demonstrated to affect the pro-degenerative actions of inflammation in neonatal hypoxia-ischemia (HI). Here we utilize a neonatal mouse model of mild HI combined with intraperitoneal administration of lipopolysaccharide (LPS) to evaluate the neuroprotective actions of hCG in the setting of endotoxin-mediated systemic inflammation. Intraperitoneal treatment of hCG shortly prior to LPS injection significantly decreased tissue loss and cystic degeneration in the hippocampal and cerebral cortex in the term-equivalent neonatal mouse exposed to mild HI. Noting that parvalbumin immunoreactive interneurons have been broadly implicated in neurodevelopmental disorders, it is notable that hCG significantly improved the injury-mediated reduction of these neurons in the cerebral cortex, striatum and hippocampus. The above findings were associated with a decrease in the amount of Iba1 immunoreactive microglia in most of these brain regions. These observations implicate hCG as an agent capable of improving the neurological morbidity associated with peripheral inflammation in the neonate affected by HI. Future preclinical studies should aim at demonstrating added neuroprotective benefit by hCG in the context of therapeutic hypothermia and further exploring the mechanisms responsible for this effect. This research is likely to advance the therapeutic role of gonadotropins as a treatment for neonates with neonatal brain injury. Key pointsO_LIIntraperitoneal administration of human chorionic gonadotropin (hCG) decreases lipopolysaccharide (LPS)-augmented hypoxic-ischemic neurodegeneration in the term-equivalent mouse neonate C_LIO_LIPretreatment with hCG reduces LPS-mediated cystic encephalomalacia of the cerebral cortex and ameliorates hippocampal tissue loss after neonatal hypoxia-ischemia (HI) C_LIO_LIhCG decreases LPS+HI-mediated parvalbumin immunoreactive interneuron loss in the cerebral cortex, hippocampus and dorsal striatum. C_LIO_LIhCG decreases LPS+HI-augmented microglial Iba1 immunoreactivity in the cerebral cortex and hippocampus. C_LI

neuroscience↗

bioRxiv2024

Mimicking an in cellulo environment for enzyme-free paper-based nucleic acid tests at the point of care

Point of care (PoC) nucleic acid amplification tests (NAATs) are a cornerstone of public health, providing the earliest and most accurate diagnostic method for many communicable diseases, such as HIV, in the same location the patient receives treatment. Communicable diseases disproportionately impact low-resource communities where NAATs are often unobtainable due to the resource intensive enzymes that drive the tests. Enzyme-free nucleic acid detection methods, such as hybridization chain reaction (HCR), use DNA secondary structures for self-driven amplification schemes producing large DNA nanostructures and capable of single molecule detection in cellulo. These thermodynamically driven DNA-based tests have struggled to penetrate the PoC diagnostic field due to their inadequate limits of detection or complex workflows. Here we present a proof-of-concept NAAT that combines HCR-based amplification of a target nucleic acid sequence with paper-based nucleic acid filtration and enrichment capable of detecting sub pM levels of synthetic DNA. We reconstruct the favorable hybridization conditions of an in cellulo reaction in vitro by incubating HCR in an evaporating, microvolume environment containing poly(ethylene glycol) as a crowding agent. We demonstrate that the kinetics and thermodynamics of DNA-DNA and DNA-RNA hybridization is enhanced by the dynamic evaporating environment and inclusion of crowding agents, bringing HCR closer to meeting PoC NAAT needs.

biophysics↗

bioRxiv2024

Taking identity-by-descent analysis into the wild: Estimating realized relatedness in free-ranging macaques

Biological relatedness is a key consideration in studies of behavior, population structure, and trait evolution. Except for parent-offspring dyads, pedigrees capture relatedness imperfectly. The number and length of DNA segments that are identical-by-descent (IBD) yield the most precise estimates of relatedness. Here, we leverage novel methods for estimating locus-specific IBD from low coverage whole genome resequencing data to demonstrate the feasibility and value of resolving fine-scaled gradients of relatedness in free-living animals. Using primarily 4-6x coverage data from a rhesus macaque (Macaca mulatta) population with available long-term pedigree data, we show that we can call the number and length of IBD segments across the genome with high accuracy even at 0.5x coverage. The resulting estimates demonstrate substantial variation in genetic relatedness within kin classes, leading to overlapping distributions between kin classes. They identify cryptic genetic relatives that are not represented in the pedigree and reveal elevated recombination rates in females relative to males, which allows us to discriminate maternal and paternal kin using genotype data alone. Our findings represent a breakthrough in the ability to understand the predictors and consequences of genetic relatedness in natural populations, contributing to our understanding of a fundamental component of population structure in the wild.

ecology↗

bioRxiv2023

The Integration of Proteogenomics and Ribosome Profiling Circumvents Key Limitations to Increase the Coverage and Confidence of Novel Microproteins

There has been a dramatic increase in the identification of non-conical translation and a significant expansion of the protein-coding genome and proteome. Among the strategies used to identify novel small ORFs (smORFs), Ribosome profiling (Ribo-Seq) is the gold standard for the annotation of novel coding sequences by reporting on smORF translation. In Ribo-Seq, ribosome-protected footprints (RPFs) that map to multiple sites in the genome are computationally removed since they cannot unambiguously be assigned to a specific genomic location, or to a specific transcript in the case of multiple isoforms. Furthermore, RPFs necessarily result in short (25-34 nucleotides) reads, increasing the chance of ambiguous and multi-mapping alignments, such that smORFs that reside in these regions cannot be identified by Ribo-Seq. Here, we show that the inclusion of proteogenomics to create a Ribosome Profiling and Proteogenomics Pipeline (RP3) bypasses this limitation to identify a group of microprotein-encoding smORFs that are missed by current Ribo-Seq pipelines. Moreover, we show that the microproteins identified by RP3 have different sequence compositions from the ones identified by Ribo-Seq-only pipelines, which can affect proteomics identification. In aggregate, the development of RP3 maximizes the detection and confidence of protein-encoding smORFs and microproteins.

bioinformatics↗

bioRxiv2023

Pharmacokinetic considerations for optimizing inhaled spray-dried pyrazinoic acid formulations

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a leading cause of death with 1.6 million deaths worldwide reported in 2021. Oral pyrazinamide (PZA) is an integral part of anti-TB regimens, but its prolonged use has the potential to drive development of PZA resistant Mtb. PZA is converted to the active moiety pyrazinoic acid (POA) by the Mtb pyrazinamidase encoded by pncA, and mutations in pncA are associated with the majority of PZA resistance. Conventional oral and parenteral therapies may result in subtherapeutic exposure in the lung, hence direct pulmonary administration of POA may provide an approach to rescue PZA efficacy for treating pncA-mutant PZA-resistant Mtb. The objectives of the current study were to i) develop novel dry powder POA formulations ii) assess their feasibility for pulmonary delivery using physicochemical characterization, iii) evaluate their pharmacokinetics (PK) in the guinea pig model and iv) develop a mechanism based pharmacokinetic model (MBM) using in vivo PK data to select a formulation providing adequate exposure in epithelial lining fluid (ELF) and lung tissue. We developed three POA formulations for pulmonary delivery and characterized their PK in plasma, ELF, and lung tissue following passive inhalation in guinea pigs. Additionally, the PK of POA following oral, intravenous and intratracheal administration was characterized in guinea pigs. The MBM was used to simultaneously model PK data following administration of POA and its formulations via the different routes. The MBM described POA PK well in plasma, ELF and lung tissue. Physicochemical analyses and MBM predictions suggested that POA maltodextrin was the best among the three formulations and an excellent candidate for further development as it has: (i) the highest ELF-to-plasma exposure ratio (203) and lung tissue-to-plasma exposure ratio (30.4) compared with POA maltodextrin and leucine (75.7/16.2) and POA leucine salt (64.2/19.3); (ii) the highest concentration in ELF (CmacELF: 171 nM) within 15.5 minutes, correlating with a fast transfer into ELF after pulmonary administration (kPM: 22.6 1/h). The data from the guinea pig allowed scaling, using the MBM to a human dose of POA maltodextrin powder demonstrating the potential feasibility of an inhaled product. Table of Contents (TOC)/Abstract Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=107 SRC="FIGDIR/small/534965v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@c548fforg.highwire.dtl.DTLVardef@3b8efborg.highwire.dtl.DTLVardef@281d94org.highwire.dtl.DTLVardef@1ae07a2_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗