Biology subjects

Lee, J.-K.

Publications and source records attributed to Lee, J.-K..

4 recordsLinked to original sources

bioRxiv2026

Single-cell RNA sequencing of peripheral blood cells identifies transcriptomic signatures in Parkinson's disease

Parkinsons disease (PD) is a progressive age-related neurodegenerative disorder characterized by both motor and non-motor symptoms. The poorly understood prodromal period, decades-long progression, and disease-phenotype heterogeneity continue to impede the development of preventive and curative therapies. A growing appreciation of immune system changes during the progression of PD suggests that evaluating peripheral immune cells may help identify signatures relevant to disease etiology. We employed single-cell RNA sequencing to profile the transcriptomes of peripheral blood mononuclear cells (PBMCs) from a cohort of 12 patients with PD and 12 healthy controls, equally distributed by sex. Analysis identified gene expression signatures specific to immune cell lineages in PD when compared with healthy controls. Analysis of the dataset indicated that aspects of the PD-related changes were associated with sex, including metabolic and inflammatory changes. Further analysis of myeloid and T cell subsets identified additional pathways and gene expression profiles associated with PD. Trajectory analysis of the myeloid and T cell datasets indicated significant changes in the distribution of cells across states of gene expression in PD compared with controls. This work provides new evidence of peripheral immune cell changes in PD utilizing high-resolution transcriptomics in a cohort powered to analyze sex as a variable. HighlightsTranscriptomic dataset in a cohort powered to analyze immune phenotype in Parkinsons disease Parkinsons disease-specific gene expression signatures in peripheral immune cell lineages Identification of sex differences in the immune cell transcriptome in Parkinsons disease Trajectory analysis identifies changes in immune cell phenotypic distribution in Parkinsons monocytes

immunology↗

bioRxiv2025

Systematic Growth Factor Profiling Platform for 3D Tumor Models Reveals Estradiol-Responsive Cellular Mechanisms of Immunotherapy Resistance

Current organoid culture systems face critical limitations: standardized growth factor formulations fail to capture patient-specific signaling requirements, and single-cell-type approaches overlook tumor-stromal interactions essential for understanding immunotherapy resistance. To address these challenges, we developed an innovative biofabrication platform that systematically integrates patient-derived three-dimensional (3D) cultures with comprehensive growth factor profiling across 128 combinations. Through systematic screening of 23 ovarian cancer patient samples and single-cell RNA sequencing, we identified two estradiol-responsive cellular populations that coordinate immunosuppression: a malignant cell fraction (MAL.PDCD5) and a cancer-associated fibroblast (CAF) fraction (FB.TNFSF10). MAL.PDCD5 cells suppress immune infiltration by downregulating antigen presentation, while FB.TNFSF10 cells promote immunosuppression through enhanced TGF-{beta} signaling. Spatial transcriptomic analysis revealed striking mutual exclusivity between FB.TNFSF10 cells and T/NK cells, providing evidence of active immune cell exclusion. Most significantly, FB.TNFSF10 abundance emerged as a robust predictor of immune checkpoint inhibitor therapy resistance across multiple cancer cohorts, independent of conventional biomarkers. This biofabrication platform provides a scalable framework for drug screening and biomarker discovery, with immediate applications in precision medicine for patient stratification and combination therapy development.

cancer biology↗

bioRxiv2018

Activation of RIG-I-mediated antiviral signaling triggers autophagy through the MAVS-TRAF6-Beclin-1 signaling axis

Autophagy has been implicated in innate immune responses against various intracellular pathogens. Recent studies have reported that autophagy can be triggered by pathogen recognizing sensors, including Toll-like receptors and cyclic guanosine monophosphate-adenosine monophosphate synthase, to participate in innate immunity. In the present study, we examined whether the RIG-I signaling pathway, which detects viral infections by recognizing viral RNA, triggers the autophagic process. The introduction of polyI:C into the cytoplasm, or Sendai virus infection, significantly induced autophagy in normal cells but not in RIG-I-deficient cells. PolyI:C transfection or Sendai virus infection induced autophagy in the cells lacking type-I interferon signaling. This demonstrated that the effect was not due to interferon signaling. RIG-I-mediated autophagy diminished by the deficiency of mitochondrial antiviral signaling protein (MAVS) or tumor necrosis factor receptor-associated factor (TRAF)6, showing that the RIG-I-MAVS-TRAF6 signaling axis was critical for RIG-I-mediated autophagy. We also found that Beclin-1 was translocated to the mitochondria, and it interacted with TRAF6 upon RIG-I activation. Furthermore, Beclin-1 underwent K63-polyubiquitination upon RIG-I activation, and the ubiquitination decreased in TRAF6-deficient cells. This suggests that the RIG-I-MAVS-TRAF6 axis induced K63-linked polyubiquitination of Beclin-1, which has been implicated in triggering autophagy. Collectively, the results of this study show that the recognition of viral infection by RIG-I is capable of inducing autophagy to control viral replication. As deficient autophagy increases the type-I interferon response, the induction of autophagy by the RIG-I pathway might also contribute to preventing an excessive interferon response as a negative-feedback mechanism.\n\nImportanceMammalian cells utilize various innate immune sensors to detect pathogens. Among those sensors, RIG-I recognizes viral RNA to detect intracellular viral replication. Although cells experience diverse physiological changes upon viral infection, studies to understand the role of RIG-I signaling have focused on the induction of type-I interferon. Autophagy is a process that sequesters cytosolic regions and degrades the contents to maintain cellular homeostasis. Autophagy participates in the immune system, and has been known to be triggered by some innate immune sensors, such as TLR4 and cGAS. We demonstrated that autophagy can be triggered by the activation of RIG-I. In addition, we also proved that MAVS-TRAF6 downstream signaling is crucial for the process. Beclin-1, a key molecule in autophagy, is translocated to mitochondria, where it undergoes K63-ubiquitination in a TRAF6-dependent manner upon RIG-I activation. As autophagy negatively regulates RIG-I-mediated signaling, the RIG-I-mediated activation of autophagy may function as a negative-feedback mechanism.

immunology↗

bioRxiv2018

Comprehensive analysis of chromothripsis in 2,658 human cancers using whole-genome sequencing

Chromothripsis is a newly discovered mutational phenomenon involving massive, clustered genomic rearrangements that occurs in cancer and other diseases. Recent studies in cancer suggest that chromothripsis may be far more common than initially inferred from low resolution DNA copy number data. Here, we analyze the patterns of chromothripsis across 2,658 tumors spanning 39 cancer types using whole-genome sequencing data. We find that chromothripsis events are pervasive across cancers, with a frequency of >50% in several cancer types. Whereas canonical chromothripsis profiles display oscillations between two copy number states, a considerable fraction of the events involves multiple chromosomes as well as additional structural alterations. In addition to non-homologous end-joining, we detect signatures of replicative processes and templated insertions. Chromothripsis contributes to oncogene amplification as well as to inactivation of genes such as mismatch-repair related genes. These findings show that chromothripsis is a major process driving genome evolution in human cancer.

genomics↗