IU Indianapolis ScholarWorks :: Browsing by Author "El-Achkar, Tarek M."

Browsing by Author "El-Achkar, Tarek M."

Now showing 1 - 10 of 61

A multimodal and integrated approach to interrogate human kidney biopsies with rigor and reproducibility: guidelines from the Kidney Precision Medicine Project
(American Physiological Society, 2021) El-Achkar, Tarek M.; Eadon, Michael T.; Menon, Rajasree; Lake, Blue B.; Sigdel, Tara K.; Alexandrov, Theodore; Parikh, Samir; Zhang, Guanshi; Dobi, Dejan; Dunn, Kenneth W.; Otto, Edgar A.; Anderton, Christopher R.; Carson, Jonas M.; Luo, Jinghui; Park, Chris; Hamidi, Habib; Zhou, Jian; Hoover, Paul; Schroeder, Andrew; Joanes, Marianinha; Azeloglu, Evren U.; Sealfon, Rachel; Winfree, Seth; Steck, Becky; He, Yongqun; D’Agati, Vivette; Iyengar, Ravi; Troyanskaya, Olga G.; Barisoni, Laura; Gaut, Joseph; Zhang, Kun; Laszik, Zoltan; Rovin, Brad H.; Dagher, Pierre C.; Sharma, Kumar; Sarwal, Minnie M.; Hodgin, Jeffrey B.; Alpers, Charles E.; Kretzler, Matthias; Jain, Sanjay; Medicine, School of Medicine
Comprehensive and spatially mapped molecular atlases of organs at a cellular level are a critical resource to gain insights into pathogenic mechanisms and personalized therapies for diseases. The Kidney Precision Medicine Project (KPMP) is an endeavor to generate three-dimensional (3-D) molecular atlases of healthy and diseased kidney biopsies by using multiple state-of-the-art omics and imaging technologies across several institutions. Obtaining rigorous and reproducible results from disparate methods and at different sites to interrogate biomolecules at a single-cell level or in 3-D space is a significant challenge that can be a futile exercise if not well controlled. We describe a “follow the tissue” pipeline for generating a reliable and authentic single-cell/region 3-D molecular atlas of human adult kidney. Our approach emphasizes quality assurance, quality control, validation, and harmonization across different omics and imaging technologies from sample procurement, processing, storage, shipping to data generation, analysis, and sharing. We established benchmarks for quality control, rigor, reproducibility, and feasibility across multiple technologies through a pilot experiment using common source tissue that was processed and analyzed at different institutions and different technologies. A peer review system was established to critically review quality control measures and the reproducibility of data generated by each technology before their being approved to interrogate clinical biopsy specimens. The process established economizes the use of valuable biopsy tissue for multiomics and imaging analysis with stringent quality control to ensure rigor and reproducibility of results and serves as a model for precision medicine projects across laboratories, institutions and consortia.
A spatially anchored transcriptomic atlas of the human kidney papilla identifies significant immune injury in patients with stone disease
(Nature, 2023-07-19) Canela, Victor Hugo; Bowen, William S.; Ferreira, Ricardo Melo; Syed, Farooq; Lingeman, James E.; Sabo, Angela R.; Barwinska, Daria; Winfree, Seth; Lake, Blue B.; Cheng, Ying-Hua; Gaut, Joseph P.; Ferkowicz, Michael; LaFavers, Kaice A.; Zhang, Kun; Coe, Fredric L.; Worcester, Elaine; Jain, Sanjay; Eadon, Michael T.; Williams, James C., Jr.; El-Achkar, Tarek M.; Urology, School of Medicine
Kidney stone disease causes significant morbidity and increases health care utilization. In this work, we decipher the cellular and molecular niche of the human renal papilla in patients with calcium oxalate (CaOx) stone disease and healthy subjects. In addition to identifying cell types important in papillary physiology, we characterize collecting duct cell subtypes and an undifferentiated epithelial cell type that was more prevalent in stone patients. Despite the focal nature of mineral deposition in nephrolithiasis, we uncover a global injury signature characterized by immune activation, oxidative stress and extracellular matrix remodeling. We also identify the association of MMP7 and MMP9 expression with stone disease and mineral deposition, respectively. MMP7 and MMP9 are significantly increased in the urine of patients with CaOx stone disease, and their levels correlate with disease activity. Our results define the spatial molecular landscape and specific pathways contributing to stone-mediated injury in the human papilla and identify associated urinary biomarkers.
Admission plasma uromodulin and the risk of acute kidney injury in hospitalized patients with cirrhosis: a pilot study
(American Physiological Society, 2019-10-01) Patidar, Kavish R.; Garimella, Pranav S.; Macedo, Etienne; Slaven, James E.; Ghabril, Marwan S.; Weber, Regina E.; Anderson, Melissa; Orman, Eric S.; Nephew, Lauren D.; Desai, Archita P.; Chalasani, Naga; El-Achkar, Tarek M.; Medicine, School of Medicine
Acute kidney injury (AKI) is a common complication in hospitalized patients with cirrhosis. Uromodulin, a protein uniquely produced by the kidney and released both in the urine and circulation, has been shown to regulate AKI and is linked to tubular reserve. Although low levels of urine uromodulin are associated with AKI after cardiac surgery, it is unclear whether circulating uromodulin can stratify the risk of AKI, particularly in a susceptible population such as hospitalized patients with cirrhosis. Thus, we investigated whether plasma uromodulin measured at the time of admission is associated with subsequent hospital-acquired AKI (defined by a rise in serum creatinine >0.3mg/dL within 48 h or ≥ 1.5 times baseline) in patients with cirrhosis. A total of 98 patients [mean age 54 yr, Model for Endstage Liver Disease Sodium (MELD-Na) score 19, and baseline creatinine of 0.95 mg/dL] were included, of which 13% (n = 13) developed AKI. Median uromodulin levels were significantly lower in patients who developed AKI compared with patients who did not (9.30 vs. 13.35 ng/mL, P = 0.02). After adjusting for age, sex, diabetes, hypertension, albumin, and MELD-Na score as covariates on multivariable logistic regression, uromodulin was independently associated with AKI [odd ratios of 1.19 (95% confidence interval 1.02, 1.37; P = 0.02)]. Lower uromodulin levels on admission are associated with increased odds of subsequent AKI in hospitalized patients with cirrhosis. Further studies are needed to better understand the role of uromodulin in the pathogenesis and as a predictive biomarker of AKI in this population. NEW & NOTEWORTHY In this study, we found that admission plasma uromodulin levels are significantly lower in patients who developed subsequent acute kidney injury (AKI) during their hospital stay compared with patients who did not. Additionally, uromodulin is independently associated with AKI development after adjusting for clinically relevant parameters such as age, sex, diabetes, hypertension, severity of cirrhosis, and kidney function. To our knowledge, this is the first study linking plasma uromodulin with AKI development in patients with cirrhosis.
Alterations in Protein Translation and Carboxylic Acid Catabolic Processes in Diabetic Kidney Disease
(MDPI, 2022-03-30) Collins, Kimberly S.; Eadon, Michael T.; Cheng, Ying-Hua; Barwinska, Daria; Ferreira, Ricardo Melo; McCarthy, Thomas W.; Janosevic, Danielle; Syed, Farooq; Maier, Bernhard; El-Achkar, Tarek M.; Kelly, Katherine J.; Phillips, Carrie L.; Hato, Takashi; Sutton, Timothy A.; Dagher, Pierre C.; Medicine, School of Medicine
Diabetic kidney disease (DKD) remains the leading cause of end-stage kidney disease despite decades of study. Alterations in the glomerulus and kidney tubules both contribute to the pathogenesis of DKD although the majority of investigative efforts have focused on the glomerulus. We sought to examine the differential expression signature of human DKD in the glomerulus and proximal tubule and corroborate our findings in the db/db mouse model of diabetes. A transcriptogram network analysis of RNAseq data from laser microdissected (LMD) human glomerulus and proximal tubule of DKD and reference nephrectomy samples revealed enriched pathways including rhodopsin-like receptors, olfactory signaling, and ribosome (protein translation) in the proximal tubule of human DKD biopsy samples. The translation pathway was also enriched in the glomerulus. Increased translation in diabetic kidneys was validated using polyribosomal profiling in the db/db mouse model of diabetes. Using single nuclear RNA sequencing (snRNAseq) of kidneys from db/db mice, we prioritized additional pathways identified in human DKD. The top overlapping pathway identified in the murine snRNAseq proximal tubule clusters and the human LMD proximal tubule compartment was carboxylic acid catabolism. Using ultra-performance liquid chromatography-mass spectrometry, the fatty acid catabolism pathway was also found to be dysregulated in the db/db mouse model. The Acetyl-CoA metabolite was down-regulated in db/db mice, aligning with the human differential expression of the genes ACOX1 and ACACB. In summary, our findings demonstrate that proximal tubular alterations in protein translation and carboxylic acid catabolism are key features in both human and murine DKD.
An atlas of healthy and injured cell states and niches in the human kidney
(Springer Nature, 2023) Lake, Blue B.; Menon, Rajasree; Winfree, Seth; Hu, Qiwen; Ferreira, Ricardo Melo; Kalhor, Kian; Barwinska, Daria; Otto, Edgar A.; Ferkowicz, Michael; Diep, Dinh; Plongthongkum, Nongluk; Knoten, Amanda; Urata, Sarah; Mariani, Laura H.; Naik, Abhijit S.; Eddy, Sean; Zhang, Bo; Wu, Yan; Salamon, Diane; Williams, James C.; Wang, Xin; Balderrama, Karol S.; Hoover, Paul J.; Murray, Evan; Marshall, Jamie L.; Noel, Teia; Vijayan, Anitha; Hartman, Austin; Chen, Fei; Waikar, Sushrut S.; Rosas, Sylvia E.; Wilson, Francis P.; Palevsky, Paul M.; Kiryluk, Krzysztof; Sedor, John R.; Toto, Robert D.; Parikh, Chirag R.; Kim, Eric H.; Satija, Rahul; Greka, Anna; Macosko, Evan Z.; Kharchenko, Peter V.; Gaut, Joseph P.; Hodgin, Jeffrey B.; KPMP Consortium; Eadon, Michael T.; Dagher, Pierre C.; El-Achkar, Tarek M.; Zhang, Kun; Kretzler, Matthias; Jain, Sanjay; Medicine, School of Medicine
Understanding kidney disease relies on defining the complexity of cell types and states, their associated molecular profiles and interactions within tissue neighbourhoods1. Here we applied multiple single-cell and single-nucleus assays (>400,000 nuclei or cells) and spatial imaging technologies to a broad spectrum of healthy reference kidneys (45 donors) and diseased kidneys (48 patients). This has provided a high-resolution cellular atlas of 51 main cell types, which include rare and previously undescribed cell populations. The multi-omic approach provides detailed transcriptomic profiles, regulatory factors and spatial localizations spanning the entire kidney. We also define 28 cellular states across nephron segments and interstitium that were altered in kidney injury, encompassing cycling, adaptive (successful or maladaptive repair), transitioning and degenerative states. Molecular signatures permitted the localization of these states within injury neighbourhoods using spatial transcriptomics, while large-scale 3D imaging analysis (around 1.2 million neighbourhoods) provided corresponding linkages to active immune responses. These analyses defined biological pathways that are relevant to injury time-course and niches, including signatures underlying epithelial repair that predicted maladaptive states associated with a decline in kidney function. This integrated multimodal spatial cell atlas of healthy and diseased human kidneys represents a comprehensive benchmark of cellular states, neighbourhoods, outcome-associated signatures and publicly available interactive visualizations.
Application of Laser Microdissection to Uncover Regional Transcriptomics in Human Kidney Tissue
(MyJove Corporation, 2020-06-09) Barwinska, Daria; Ferkowicz, Michael J.; Cheng, Ying-Hua; Winfree, Seth; Dunn, Kenneth W.; Kelly, Katherine J.; Sutton, Timothy A.; Rovin, Brad H.; Parikh, Samir V.; Phillips, Carrie L.; Dagher, Pierre C.; El-Achkar, Tarek M.; Eadon, Michael T.; Medicine, School of Medicine
Gene expression analysis of human kidney tissue is an important tool to understand homeostasis and disease pathophysiology. Increasing the resolution and depth of this technology and extending it to the level of cells within the tissue is needed. Although the use of single nuclear and single cell RNA sequencing has become widespread, the expression signatures of cells obtained from tissue dissociation do not maintain spatial context. Laser microdissection (LMD) based on specific fluorescent markers would allow the isolation of specific structures and cell groups of interest with known localization, thereby enabling the acquisition of spatially-anchored transcriptomic signatures in kidney tissue. We have optimized an LMD methodology, guided by a rapid fluorescence-based stain, to isolate five distinct compartments within the human kidney and conduct subsequent RNA sequencing from valuable human kidney tissue specimens. We also present quality control parameters to enable the assessment of adequacy of the collected specimens. The workflow outlined in this manuscript shows the feasibility of this approach to isolate sub-segmental transcriptomic signatures with high confidence. The methodological approach presented here may also be applied to other tissue types with substitution of relevant antibody markers.
Autosomal Dominant Tubulointerstitial Kidney Disease: A New Tool to Guide Genetic Testing
(Elsevier, 2020-09) LaFavers, Kaice A.; El-Achkar, Tarek M.; Medicine, School of Medicine
Autosomal dominant tubulointerstitial disease (ADTKD) is a dominantly inherited progressive nonglomerular disease. Several factors, such as a nonspecific clinical presentation and relative rarity, impede the phenotyping of ADTKD into clinically relevant subtypes and impair the appropriate implementation of genetic testing. The study by Olinger et al. describes the largest multicenter ADTKD cohort, which is likely to become a key resource. The authors also provide a new clinical tool that could guide diagnosis and genetic testing.
Cellular and Molecular Interrogation of Kidney Biopsy Specimens
(Wolters Kluwer, 2022) Eadon, Michael T.; Dagher, Pierre C.; El-Achkar, Tarek M.; Medicine, School of Medicine
Purpose of review: Traditional histopathology of the kidney biopsy specimen has been an essential and successful tool for the diagnosis and staging of kidney diseases. However, it is likely that the full potential of the kidney biopsy has not been tapped so far. Indeed, there is now a concerted worldwide effort to interrogate kidney biopsy samples at the cellular and molecular levels with unprecedented rigor and depth. This review examines these novel approaches to study kidney biopsy specimens and highlights their potential to refine our understanding of the pathophysiology of kidney disease and lead to precision-based diagnosis and therapy. Recent findings: Several consortia are now active at studying kidney biopsy samples from various patient cohorts with state-of-the art cellular and molecular techniques. These include advanced imaging approaches as well as deep molecular interrogation with tools such as epigenetics, transcriptomics, proteomics and metabolomics. The emphasis throughout is on rigor, reproducibility and quality control. Summary: Although these techniques to study kidney biopsies are complementary, each on its own can yield novel ways to define and classify kidney disease. Therefore, great efforts are needed in order to generate an integrated output that can propel the diagnosis and treatment of kidney disease into the realm of precision medicine.
Circulating Uromodulin inhibits systemic oxidative stress by inactivating the TRPM2 channel
(American Association for the Advancement of Science, 2019-10) LaFavers, Kaice A.; Macedo, Etienne; Garimella, Pranav S.; Lima, Camila; Khan, Shehnaz; Myslinski, Jered; McClintick, Jeanette; Witzmann, Frank A.; Winfree, Seth; Phillips, Carrie; Hato, Takashi; Dagher, Pierre; Wu, Xue-Ru; El-Achkar, Tarek M.; Micanovic, Radmila; Medicine, School of Medicine
High serum concentrations of kidney-derived protein uromodulin (Tamm-Horsfall protein or THP) have recently been shown to be independently associated with low mortality in both older adults and cardiac patients, but the underlying mechanism remains unclear. Here, we show that THP inhibits the generation of reactive oxygen species (ROS) both in the kidney and systemically. Consistent with this experimental data, the concentration of circulating THP in patients with surgery-induced acute kidney injury (AKI) correlated with systemic oxidative damage. THP in the serum dropped after AKI, and was associated with an increase in systemic ROS. The increase in oxidant injury correlated with post-surgical mortality and need for dialysis. Mechanistically, THP inhibited the activation of the transient receptor potential cation channel, subfamily M, member 2 (TRPM2) channel. Furthermore, inhibition of TRPM2 in vivo in a mouse model, mitigated the systemic increase in ROS during AKI and THP deficiency. Our results suggest that THP is a key regulator of systemic oxidative stress by suppressing TRPM2 activity and our findings might help to explain how circulating THP deficiency is linked with poor outcomes and increased mortality.
Clinical, histopathologic and molecular features of idiopathic and diabetic nodular mesangial sclerosis in humans
(Oxford University Press, 2021) Eadon, Michael T.; Lampe, Sam; Baig, Mirza M.; Collins, Kimberly S.; Ferreira, Ricardo Melo; Mang, Henry; Cheng, Ying-Hua; Barwinska, Daria; El-Achkar, Tarek M.; Schwantes-An, Tae-Hwi; Winfree, Seth; Temm, Constance J.; Ferkowicz, Michael J.; Dunn, Kenneth W.; Kelly, Katherine J.; Sutton, Timothy A.; Moe, Sharon M.; Moorthi, Ranjani N.; Phillips, Carrie L.; Dagher, Pierre C.; Medicine, School of Medicine
Background: Idiopathic nodular mesangial sclerosis, also called idiopathic nodular glomerulosclerosis (ING), is a rare clinical entity with an unclear pathogenesis. The hallmark of this disease is the presence of nodular mesangial sclerosis on histology without clinical evidence of diabetes mellitus or other predisposing diagnoses. To achieve insights into its pathogenesis, we queried the clinical, histopathologic and transcriptomic features of ING and nodular diabetic nephropathy (DN). Methods: All renal biopsy reports accessioned at Indiana University Health from 2001 to 2016 were reviewed to identify 48 ING cases. Clinical and histopathologic features were compared between individuals with ING and DN (n = 751). Glomeruli of ING (n = 5), DN (n = 18) and reference (REF) nephrectomy (n = 9) samples were isolated by laser microdissection and RNA was sequenced. Immunohistochemistry of proline-rich 36 (PRR36) protein was performed. Results: ING subjects were frequently hypertensive (95.8%) with a smoking history (66.7%). ING subjects were older, had lower proteinuria and had less hyaline arteriolosclerosis than DN subjects. Butanoate metabolism was an enriched pathway in ING samples compared with either REF or DN samples. The top differentially expressed gene, PRR36, had increased expression in glomeruli 248-fold [false discovery rate (FDR) P = 5.93 × 10-6] compared with the REF and increased 109-fold (FDR P = 1.85 × 10-6) compared with DN samples. Immunohistochemistry revealed a reduced proportion of cells with perinuclear reaction in ING samples as compared to DN. Conclusions: Despite similar clinical and histopathologic characteristics in ING and DN, the uncovered transcriptomic signature suggests that ING has distinct molecular features from nodular DN. Further study is warranted to understand these relationships.

Browsing by Author "El-Achkar, Tarek M."

Results Per Page

Sort Options