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Biology subjects

Curry, J.

Publications and source records attributed to Curry, J..

4 recordsLinked to original sources

Compound Delivery of eVLPs Enhances Prime Editing for Targeted Genome Engineering and High-Throughput Screening

Engineered virus-like particles (eVLPs) enable transgene-free ribonucleoprotein delivery for genome editing applications, yet optimized delivery strategies for high-throughput applications remain unexplored. Prime editing enables precise genomic modifications but suffers from limited efficiency that constrains its widespread adoption. Here, we present PRIME-VLP (Progressive Repeated Infections for Maximized Editing via Virus-Like Particles), a delivery strategy that enhances prime editing efficiency for both targeted genome engineering and high-throughput prime editing screening. PRIME-VLP leverages the temporal dynamics of eVLP-mediated editing through multiple sequential transductions with sub-saturating eVLP doses delivered at optimal intervals. This approach achieves 1.5 to 2.8-fold improvements in editing efficiency across diverse genomic targets and cell types. PRIME-VLP maintains high specificity without increasing off-target effects, compromising cellular viability or causing transcriptional perturbations. By decoupling pegRNA and editor delivery through pegRNA-free eVLPs, PRIME-VLP enables pooled prime editing screens, circumventing transgene silencing limitations of conventional lentiviral-based screens. Using a 6,000-pegRNA library targeting TP53, PRIME-VLP achieved 2.8-fold higher editing efficiency and improved reproducibility compared to conventional lentiviral delivery. An eVLP-based screen identified functional TP53 loss-of-function variants that confer resistance to MDM2 inhibition by Nutlin-3. This work expands the versatility of eVLPs beyond their current in vivo therapeutic applications, demonstrating their promise for high-throughput functional genomics by overcoming the delivery limitations of lentiviral systems.

genomics↗

Distinct cell types along thick ascending limb express pathways for monovalent and divalent cation transport

Kidney thick ascending limb cells reabsorb sodium, potassium, calcium, and magnesium and contribute to urinary concentration. These cells are typically viewed as of a single type that recycles potassium across the apical membrane and generates a lumen-positive transepithelial voltage driving calcium and magnesium reabsorption, although variability in potassium channel expression has been reported. Additionally, recent transcriptomic analyses suggest that different cell types exist along this segment, but classifications have varied and have not led to a new consensus model. We used immunolocalization, electrophysiology and enriched single nucleus RNA-Seq to identify thick ascending limb cell types in rat, mouse and human. We identified three major TAL cell types defined by expression of potassium channels and claudins. One has apical potassium channels, low basolateral potassium conductance, and is bordered by a sodium-permeable claudin. A second lacks apical potassium channels, has high basolateral potassium conductance and is bordered by calcium- and magnesium-permeable claudins. A third type also lacks apical potassium channels and has a high basolateral potassium conductance, but these cells are ringed by sodium-permeable claudins. The recognition of diverse cell types resolves longstanding questions about how solute transport can be modulated selectively and how disruption of these cells leads to human disease.

physiology↗

Epithelial heme oxygenase-1 enhances colonic tumorigenesis by inhibiting ferroptosis

Induction of heme oxygenase-1 (HO-1/Hmox1) is broadly considered cytoprotective, but the role of colonic epithelial HO-1 in colitis-associated tumorigenesis is poorly defined. HO-1 catabolizes heme, releasing ferrous iron, a key driver of oxidative stress and lipid peroxidation. We observed that colonic epithelial HO-1 is induced during colitis and tumorigenesis. We also found that HO-1 is upregulated in ferroptosis-inducing conditions in murine and human colonic epithelial organoids, and correlated with lipid peroxidation and ferroptosis markers in colonic tumors. In colonic epithelial organoids exposed to heme, deletion of Hmox1 amplified a compensatory oxidative stress and detoxification transcriptional program, likely reflecting unresolved oxidative and non-oxidative toxicity from heme. In vivo, epithelial HO-1 deficient mice developed significantly fewer and smaller tumors compared to littermate controls in a colitis-associated tumorigenesis model, despite similar inflammatory injury. Tumors from knockout mice exhibited reduced iron levels, decreased lipid peroxidation, lower oxidative DNA damage, and decreased proliferation. Single-cell RNA sequencing of tumor epithelial cells revealed a shift from a proliferative to a stress-adaptive program with loss of HO-1. These findings identify epithelial HO-1 as a context-dependent regulator of tumorigenesis: protective against acute heme toxicity, but promoting iron-dependent oxidative damage and proliferation in the setting of chronic inflammation.

cancer biology↗

Faster Cognitive Decline in Dementia due to Alzheimer Disease with Clinically Undiagnosed Lewy Body Disease

Neuropathology has demonstrated a high rate of comorbid pathology in dementia due to Alzheimers disease (ADD). The most common major comorbidity is Lewy body disease (LBD), either as dementia with Lewy bodies (AD-DLB) or Alzheimers disease with Lewy bodies (AD-LB), the latter representing subjects with ADD and LBD not meeting neuropathological distribution and density thresholds for DLB. Although it has been established that ADD subjects with undifferentiated LBD have a more rapid cognitive decline than those with ADD alone, it is still unknown whether AD-LB subjects, who represent the majority of LBD and approximately one-third of all those with ADD, have a different clinical course. Subjects with dementia included those with \"pure\" ADD (n = 137), AD-DLB (n = 64) and AD-LB (n = 114), all with two or more complete Mini Mental State Examinations (MMSE) and a full neuropathological examination. Linear mixed models assessing MMSE change showed that the AD-LB group had significantly greater decline compared to the ADD group ({beta} = -0.69, 95% CI: -1.05, -0.33, p<0.001) while the AD-DLB group did not ({beta} = -0.30, 95% CI: -0.73, 0.14, p = 0.18). Of those with AD-DLB and AD-LB, only 66% and 2.1%, respectively, had been diagnosed with LBD at any point during their clinical course. The probable cause of LBD clinical detection failure is the lack of a sufficient set of characteristic core clinical features. Core DLB clinical features were not more common in AD-LB as compared to ADD. Compared with clinically-diagnosed AD-DLB subjects, those that were clinically undetected had significantly lower prevalences of parkinsonism (p = 0.046), visual hallucinations (p = 0.0008) and dream enactment behavior (0.013). Clinical identification of ADD with LBD would allow stratified analyses of ADD clinical trials, potentially improving the probability of trial success.

neuroscience↗