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Sorace, A. G.

Publications and source records attributed to Sorace, A. G..

5 recordsLinked to original sources

Unmasking Early Renal Fibrosis in Polycystic Kidney Disease Using Noninvasive Precision Molecular MRI of Collagen

Fibrotic remodeling of extracellular matrix is a central driver of autosomal dominant polycystic kidney disease (ADPKD) progression since early stages of the disease. Unfortunately, it cannot be assessed with currently available methodologies before irreversible structural and functional decline, creating a diagnostic blind spot that hinders accurate early risk stratification and management. Here, we report the development of Gd-hProCA32.Collagen, a collagen -targeted protein MRI contrast agent that enables precision molecular MRI (pMRI) of early fibrosis by directly imaging collagen type I deposition in vivo before conventional laboratory and imaging methods detect changes in kidneys and liver of Pkhd1PCK/PCK (PCK) rats and Pkd2 mutant mice. Gd-hProCA32.Collagen, used at 10-fold lower dose, outperformed the widely clinically used agent gadobutrol (Gadovist), detecting approximately 2.8-fold greater total renal cyst volume ([~]8,500 vs [~]3,000 mm3, p<0.0001) and 1.5-fold higher total cyst count ([~]245 vs [~]160, p<0.0001), with superior T1W and T2W kidney AUC (p<0.01 and p<0.001) and preferential sensitivity to small and medium cysts. Signal enhancement in kidneys and liver correlated strongly with histological collagen burden quantified by Sirius red staining, whereas Gadovist showed no meaningful correlation. Gd-hProCA32.Collagen also enabled in vivo visualization of previously undetectable changes resembling radial striations at sites of microcyst cluster-adjacent microfibrosis and sustained delayed MRI enhancement due to specific collagen binding. These results reveal a previously inaccessible subclinical fibrotic phase of cystic kidney and liver disease and establish collagen-targeted pMRI as a strategy for early noninvasive detection and spatial mapping of multi-organ extracellular matrix remodeling when conventional biomarkers remain non-discriminating. One-sentence summaryWe report a first-in-class collagen-targeted MRI contrast agent with Precision molecular MRI that noninvasively reveals a previously inaccessible subclinical fibrotic phase of polycystic kidney disease across kidney and liver, overcoming limitations of current diagnostic methodology.

molecular biology↗

Headbutting goats self-inflict traumatic brain injury

Traumatic brain injury (TBI) is a characteristic feature of neurodegenerative diseases such as Alzheimers disease and chronic traumatic encephalopathy. Small animal models have been used to establish clinically relevant biomarkers of neuropathology, however, they show significant anatomical differences from humans and are affected by artificial experimental manipulations, making them often unsuitable for longitudinal study of repetitive mild TBI. There is a need for more diverse and translationally relevant animal models to better understand disease onset and development. Building on a previous study of neuropathology in headbutting bovids in the wild, this pilot study investigated whether freely headbutting domestic goats, which naturally engage in low-intensity, high-frequency head impacts, accumulate measurable biomarkers of neurodegeneration in cerebrospinal fluid (CSF) and brain tissue. Over a six-month period, three male goats (Capra hircus) were allowed to freely headbutt under continuous video surveillance. Monthly CSF samples were collected, and concentrations of key neurodegeneration biomarkers were measured via multiplex immunoassays, including amyloid-{beta} peptides (A{beta}40, A{beta}42), total and phosphorylated tau (tTau and pTau), glial fibrillary acidic protein (GFAP), S100 calcium-binding protein B (S100B), and neurofilament M (NF-M). Imaging studies were completed for non-invasive assessment of glucose metabolism ([18F]-FDG) and neuroinflammation via translocator protein (TSPO, [18F]DPA-714). Postmortem immunohistochemistry was conducted on prefrontal cortical tissues using antibodies targeting pTau, GFAP, and S100B. Head impact kinematics were quantified using horn-mounted accelerometer and inclinometer sensors that recorded linear acceleration, rotational velocity, and head orientation during naturally occurring headbutting events. Several notable trends were observed. Phosphorylated tau as well as reactive astrocytes were detected in the brain tissue, mirrored by elevated GFAP detected in the CSF. PET TSPO did not illustrate a significant signal, however, PET FDG revealed frontal-dominant activity in all goats, and one with asymmetrical activation. Overall, the goats sustained 5,000-7,000 head impacts each over six months. Accelerometer measurements recorded forces up to 388 N and peak acceleration up to 16.5 g. This multi-modal observational study is the first to characterize neurodegeneration biomarkers and kinematics in headbutting goats. Even at one year old, the combination of pTau and gliosis in both the brain tissue and CSF indicates that the goats repetitive head impacts begin to show neurodegenerative consequences early in life. Likely, the severity of these consequences increases with headbutts and age, eventually resulting in chronic neurodegeneration. This system shows promise as a large-animal model for the longitudinal study of the onset and progression of neurodegenerative disease.

neuroscience↗

Modeling tumor dynamics and predicting response to chemo-, targeted-, and immune-therapies in a murine model of pancreatic cancer

We seek to establish a parsimonious mathematical framework for understanding the interaction and dynamics of the response of pancreatic cancer to the NGC triple chemotherapy regimen (mNab-paclitaxel, gemcitabine, and cisplatin), stromal-targeting drugs (calcipotriol and losartan), and an immune checkpoint inhibitor (anti-PD-L1). We developed a set of ordinary differential equations describing changes in tumor size (growth and regression) under the influence of five cocktails of treatments. Model calibration relies on three tumor volume measurements obtained over a 14-day period in a genetically engineered pancreatic cancer model (KrasLSLG12D-Trp53LSLR172H-Pdx1-Cre). Our model reproduces tumor growth in the control and treatment scenarios with an average concordance correlation coefficient (CCC) of 0.99{+/-}0.01. We conduct leave-one-out predictions (average CCC=0.74{+/-}0.06), mouse-specific predictions (average CCC=0.75{+/-}0.02), and hybrid, group-informed, mouse-specific predictions (average CCC=0.85{+/-}0.04). The developed mathematical model demonstrates high accuracy in fitting the experimental tumor data and a robust ability to predict tumor response to treatment. This approach has important implications for optimizing combination NGC treatment strategies.

bioinformatics↗

A mouse model of ZTTK syndrome reveals indispensable SON functions in organ development and hematopoiesis

Rare diseases are underrepresented in biomedical research, leading to insufficient awareness. Zhu-Tokita-Takenouchi-Kim (ZTTK) syndrome is a rare disease caused by genetic alterations that result in heterozygous loss-of-function of SON. While ZTTK syndrome patients suffer from numerous symptoms, the lack of model organisms hamper our understanding of both SON and this complex syndrome. Here, we developed Son haploinsufficiency (Son+/-) mice as a model of ZTTK syndrome and identified the indispensable roles of Son in organ development and hematopoiesis. Son+/- mice recapitulated clinical symptoms of ZTTK syndrome, including growth retardation, cognitive impairment, skeletal abnormalities, and kidney agenesis. Furthermore, we identified hematopoietic abnormalities in Son+/- mice, similar to those observed in human patients. Surface marker analyses and single-cell transcriptome profiling of hematopoietic stem and progenitor cells revealed that Son haploinsufficiency inclines cell fate toward the myeloid lineage but compromises lymphoid lineage development by reducing key genes required for lymphoid and B cell lineage specification. Additionally, Son haploinsufficiency causes inappropriate activation of erythroid genes and impaired erythroid maturation. These findings highlight the importance of the full gene dosage of Son in organ development and hematopoiesis. Our model serves as an invaluable research tool for this rare disease and related disorders associated with SON dysfunction.

genetics↗

RORγt-Expressing Pathogenic CD4+T Cells Cause Brain Inflammation During Chronic Colitis

Neurobehavioral disorders and brain abnormalities have been extensively reported in both Crohns Disease (CD) and Ulcerative Colitis (UC) patients. However, the mechanism causing neuropathological disorders in inflammatory bowel disease (IBD) patients remains unknown. Studies have linked the Th17 subset of CD4+T cells to brain diseases associated with neuroinflammation and cognitive impairment, including multiple sclerosis (MS), ischemic brain injury and Alzheimers disease. To better understand how CD4+T lymphocytes, contribute to brain pathology in chronic intestinal inflammation, we investigated the development of brain inflammation in the T cell transfer model of chronic colitis. Our findings demonstrate that CD4+T cells infiltrate the brain of colitic Rag1-/- mice in proportional levels to colitis severity. Colitic mice developed hypothalamic astrogliosis that correlated with neurobehavioral disorders. Moreover, the brain-infiltrating CD4+T cells expressed Th17 cell transcription factor ROR{gamma}t and displayed a pathogenic Th17 cellular phenotype similar to colonic Th17 cells. Adoptive transfer of ROR{gamma}t-deficient naive CD4+T cells failed to cause brain inflammation and neurobehavioral disorders in Rag1-/- recipients, with significantly less brain infiltration of CD4+T cells. These findings suggest that pathogenic ROR{gamma}t+CD4+T cells that aggravate colitis migrate preferentially into the brain, contributing to brain inflammation and neurobehavioral disorders, thereby linking colitis severity to neuroinflammation.

immunology↗