Cells exhibit diverse sizes and shapes, tailored for functional needs of tissues. Lung alveoli are lined by large, extremely thin epithelial alveolar type-1 cells (AT1s). Their characteristic morphology is essential for lung function and must be restored after injury. The mechanisms underlying small, cuboidal alveolar type-2 cells (AT2s) differentiation into thin AT1s remain elusive. Here, we demonstrated that AT2s undergo a stepwise morphological transformation characterized by the development of a unique thick microtubule (MT) bundle organization, critical for AT1 morphology. Using AT2 cultures and in vivo genetic loss of function models, we found that MT bundling process occurs in a transitional cell state during AT2 differentiation and was regulated by the TP53/TAU signaling axis. Notably, TAU underwent a linear clustering process, forming beads-on-a-string-like pattern that preceded thick MT-bundle formation. Genetic gain or loss of function of TAU in mouse or human models, prevented the formation of thick MT-bundles, highlighting the critical role of precise TAU levels in generating ultra-thin AT1s. This defect was associated with increased tissue fibrosis following bleomycin-induced injury in vivo. GWAS analysis revealed risk variants in MAPT locus in lung diseases. Moreover, TP53 controlled TAU expression and its loss phenocopied TAU deficiency. This work revealed an unexpected role for TAU in organizing MT-bundles during AT2 differentiation.
Satoshi Konishi, Khaliun Enkhbayar, Shuyu Liu, Naoya Miyashita, Yoshihiko Kobayashi, Vera Hutchison, Ashna Sai, Pankaj Agarwal, Jonathan Witonsky, Nathan D. Jackson, Max A. Seibold, Jichao Chen, Aleksandra Tata, Purushothama Rao Tata
Vision begins in the outer segment compartment of photoreceptor cells, which is constantly renewed through the addition of membrane material at its base and ingestion of mature membranes at its tip by the retinal pigment epithelium (RPE). The close apposition of outer segments to the RPE is believed to be critical for maintaining this renewal process. Yet, in several retinal diseases, expansion of the subretinal space separating photoreceptors from the RPE does not immediately impact photoreceptor functionality. Here, we analyzed outer segment function and renewal in the Adam9 knockout mouse characterized by a major expansion of the subretinal space. Surprisingly, photoreceptor-RPE separation affected neither the sensitivity of photoreceptor light-responses nor the normal rate of outer segment renewal in this mouse prior to the onset of photoreceptor degeneration. The latter is achieved through the formation of elongated RPE “pseudopods” extending across the enlarged subretinal space to ingest outer segment tips. This work suggests that pseudopod formation may underlie the persistence of photoreceptor function in human diseases accompanied by photoreceptor-RPE separation, such as vitelliform macular dystrophy or age-related macular degeneration associated with subretinal drusenoid deposits.
Tylor R. Lewis, Carson M. Castillo, Sebastien Phan, Camilla R. Shores, Kylie K. Hayase, Keun-Young Kim, Mark H. Ellisman, Oleg Alekseev, Marie E. Burns, Vadim Y. Arshavsky
BACKGROUND. Infection by Trypanosoma cruzi, the agent of Chagas disease, is endemic to the Americas and can irreparably damage the cardiac and gastrointestinal systems during decades of parasite persistence. Diagnosis of chronic infection requires confirmation by multiple serological assays due to the imperfect performance of existing tests. Current serology tests were developed using small specimen sets predominantly from South America, and lower performance has been observed in patients who acquired infection in Central America and Mexico. METHODS. To improve Chagas disease serology, we evaluated antibody responses against the entire T. cruzi proteome with phage display immunoprecipitation sequencing and further evaluated high prevalence antigens by immunoassay. We utilized specimen sets representing Mexico, Central America and South America and varying cardiac disease presentations, from 185 cases and 143 controls. RESULTS. We identified over 1,300 antigenic T. cruzi peptides. A trans-sialidase antigen demonstrated high seroprevalence across all regions and has not previously been described as a diagnostic target. Orthogonal validation of this peptide demonstrated increased antibody reactivity for infections originating from Central America. CONCLUSION. This study provides proteome-wide identification of seroreactive T. cruzi peptides across a range of endemic populations not previously represented in antigen discovery and identifies a trans-sialidase peptide antigen (TS23) with potential for translation into diagnostic serological assays. TRIAL REGISTRATION. Not Applicable.
Hannah M. Kortbawi, Ryan J. Marczak, Jayant V. Rajan, Nash L. Bulaong, John E. Pak, Wesley Wu, Grace Wang, Anthea Mitchell, Aditi Saxena, Aditi Maheshwari, Rachel Alfaro Leone, Charles J. Fleischmann, Emily A. Kelly, Evan Teal, Rebecca L. Townsend, Susan L. Stramer, Emi E. Okamoto, Jacqueline E. Sherbuk, Eva H. Clark, Robert H. Gilman, Rony Pedro Colanzi, Efstathios D. Gennatas, Caryn Bern, Joseph L. DeRisi, Jeffrey D. Whitman
Ceramides are essential skin lipids for maintaining the mammalian skin permeability barrier, which protects against external stimuli. The precursor of epidermal ceramides, glucosylceramides (GlcCer), is synthesized within granular keratinocytes while its precise cellular transport mechanisms remain poorly characterized. Here, we identified three pathogenic variants in the GLTP gene, which encodes glycolipid transfer protein, in five unrelated families with nonsyndromic epidermal differentiation disorder presenting with generalized skin scaling. The biallelic GLTP variants resulted in loss of competent GLTP expression. CRISPR/Cas9-generated Gltp knockout mice exhibited lethal barrier defects, partially recapitulating the clinical features of our patients. We demonstrated that GLTP facilitated GlcCer transport in differentiated keratinocytes, with its deficiency causing impaired GlcCer trafficking and consequent aberrant retention in lysosomes, thereby disrupted lysosome function. The lysosomal dysfunction impaired autophagy flux, resulting in delayed keratinocyte terminal differentiation, which is expected to compromise the skin barrier integrity and ultimate abnormal scaling. Pharmaceutical inhibition of GlcCer synthesis effectively rescued both autophagy and keratinocyte differentiation defects. Our findings establish GLTP as a novel underlying gene for nonsyndromic epidermal differentiation disorders and unravel its essential role in maintaining skin homeostasis during terminal differentiation by mediating epidermal GlcCer transport.
Zeqiao Zhang, Shimiao Huang, Adam Jackson, Elizabeth A. Jones, Siddharth Banka, Chao Yang, Sisi Zhao, Kunlun Lv, Sha Peng, Zhimiao Lin, Huijun Wang
BACKGROUND. Plasma heparan sulfate, a glycosaminoglycan released during endothelial glycocalyx degradation, predicts sepsis mortality. Chondroitin sulfate is a circulating glycosaminoglycan not specific to glycocalyx degradation; its relevance to sepsis is unknown. METHODS. We studied the associations of plasma chondroitin sulfate with (a) mortality in patients with sepsis-associated hypotension and (b) the relative effectiveness of a randomly-assigned liberal versus restrictive intravenous fluid resuscitation strategy. We selected 574 patients enrolled in the Crystalloid Liberal or Vasopressors Early Resuscitation in Sepsis trial using an outcome-enriched sampling strategy. We used liquid chromatography-mass spectrometry to quantify plasma chondroitin sulfate. In comparison, we measured hyaluronic acid as a glycocalyx degradation marker and IL-6 as an inflammatory biomarker. We conducted Cox proportional hazards regression analyses to examine associations of baseline biomarker concentrations with mortality and resuscitation strategy effectiveness. We used inverse probability of selection weights and generalized raking to account for the non-representative sampling design. RESULTS. Plasma chondroitin sulfate, hyaluronic acid, and IL-6 were associated with mortality within 90 days. As baseline chondroitin sulfate increased, subsequent randomization to a restrictive strategy was increasingly beneficial (p = 0.022): treatment effect hazard ratio (restrictive versus liberal) for mortality was estimated as 1.49 (95% CI 0.98–2.27), 1.30 (1.00–1.69), 1.09 (0.82–1.44), 0.88 (0.66–1.16), and 0.71 (0.52–0.97) for 10th, 25th, 50th, 75th and 90th percentiles of baseline chondroitin sulfate. CONCLUSIONS. Plasma chondroitin sulfate predicts sepsis mortality and may modify the response to a subsequent liberal vs. restrictive intravenous fluid resuscitation strategy. TRIAL. ClinicalTrials.gov NCT03434028.
Kaori Oshima, Bailu Yan, Ran Tao, Gustavo Amorim, Chiara Di Gravio, Sarah A. McMurtry, Ryan C. Burke, Yunbi Nam, Ina Nikolli, Max S. Kravitz, Daniel Stephenson, Aaron Issaian, Kirk C. Hansen, Angelo D'Alessandro, Ivor S. Douglas, Wesley H. Self, Christopher J. Lindsell, Carolyn Leroux, Angelika Ringor, Michael A. Matthay, Jonathan S. Schildcrout, Nathan I. Shapiro, Eric P. Schmidt
Mycobacterium tuberculosis (Mtb) remains a global health crisis, ranking among the deadliest infectious diseases worldwide. In response to the World Health Organization’s call for therapeutic vaccines to complement antibiotic regimens and reduce tuberculosis (TB) treatment duration, we developed an intranasal DNA vaccine fusing the Mtb stringent response gene relMtb with the gene encoding the dendritic cell-targeting chemokine Mip3a/CCL20. Administered alongside the first-line regimen, this vaccine accelerated stable cure in immunocompetent murine TB models, reducing lung inflammation and eliciting robust and sustained RelMtb-stimulated T-cell responses systemically and locally. The Mip3a/relMtb vaccine enhanced dendritic cell recruitment, activation, and spatial coordination with T cells, suggesting improved innate-adaptive immune synergy. Notably, it augmented the efficacy of a novel drug-resistant TB regimen as well. Critically, the vaccine induced analogous antigen-stimulated T-cell immunity in nonhuman primates, the gold standard for preclinical TB vaccine evaluation, with responses detected in blood and bronchoalveolar lavage mirroring those observed in the murine models. These findings underscore the potential of this strategy to advance therapeutic TB vaccine development targeting Mtb persisters while providing a framework to define correlates of vaccine-mediated protection.
Styliani Karanika, Tianyin Wang, Addis Yilma, Jennie Ruelas Castillo, James T. Gordy, Hannah Bailey, Darla Quijada, Kaitlyn Fessler, Rokeya Tasneen, Elisa M. Rouse Salcido, Farah Shamma, Harley T. Harris, Fengyixin Chen, Rowan E. Bates, Heemee Ton, Jacob Meza, Yangchen Li, Alannah D. Taylor, Jean J. Zheng, Jiaqi Zhang, Theodoros Karantanos, Amanda R. Maxwell, Eric L. Nuermberger, J. David Peske, Richard B. Markham, Petros C. Karakousis
Radiotherapy (RT) is a central treatment for prostate cancer (PCa), acting by inducing DNA double-strand breaks (DSBs). Tumor ability to repair these breaks limits RT efficacy, making DSB repair inhibitors potential radiosensitizers. Therefore, tumor-specific radiosensitization strategies are critically needed for PCa. Approximately 50% of PCa cases harbor the TMPRSS2-ERG gene fusion, leading to overexpression of the ERG transcription factor (ERG+). We demonstrate that ERG+ tumors shift DSB repair toward the PARP1-dependent end-joining (PARP1-EJ) pathway. Proteomic and western blot analyses revealed elevated PARP1, XRCC1, and LIG3 in ERG+ cells. PARP inhibition with olaparib increased residual γH2AX/53BP1 foci post-irradiation in ERG+ cells, indicating enhanced radiosensitization. In tissue-slice-cultures (TSCs) from 53 tumors of 40 high-risk PCa patients, olaparib selectively increased H2AX/53BP1 foci selectively in ERG+ samples. ERG+ patient-derived organoids also showed significantly delayed growth and survival when treated with olaparib plus RT compared to either treatment alone. Interestingly, ERG-negative cells within ERG+ TSCs were similarly radiosensitized by olaparib, likely through bystander effect, with residual 53BP1 foci levels comparable to ERG+ cells, confirmed by medium exchange experiments. These findings suggest that ERG expression promotes dependency on PARP1-EJ, rendering ERG+ PCa more susceptible to PARP inhibition. Combining PARP inhibitors with RT may offer a tumor-selective radiosensitization for ERG+ PCa patients.
Sabrina Köcher, Mohamed E. Elsesy, Ayham Moustafa, Wahid Mohammadi, Adriana Perugachi Heinsohn, Yamini Nagaraj, Su Jung Oh-Hohenhorst, Jan Hahn, Bente Siebels, Thomas Mair, Susanne Burdak-Rothkamm, Pierre Tennstedt, Ronald Simon, Tobias Lange, Derya Tilki, Thorsten Frenzel, Tobias Maurer, Cordula Petersen, Hartmut Schlüter, Carsten Bokemeyer, Gunhild von Amsberg, Kai Rothkamm, Wael Y. Mansour
Aging commonly causes decline of testosterone or estrogen, leading to overaccumulation of fatness in males or females, respectively. Although such phenomenon can be readily explained by estrogen’s direct action on adipocytes in females, accumulative evidence does not support the direct action of testosterone in adipocyte lipid metabolism, suggesting that there is a missing intermediary link. Herein, we propose that glycoprotein hormone β5 (GPHB5) is the intermediary linkage between testosterone and the regulation of adiposity. In clinical samples, blood levels of GPHB5 were correlated negatively with men’s ages, and positively with circulating testosterone. Testosterone directly stimulated the expression of GPHB5 in cultured cells, pharmacological blockade of androgen receptor (AR) functions abrogated such effect. Knockout of AR led to not only development of obesity but also reduction of GPHB5 expression. Genetic ablation of GPHB5 in the males, but not in the females, lowered the browning of white adipose tissue, diminished energy expenditure and caused severe obesity. Importantly, elevated blood testosterone didn’t exert its catabolic actions in GPHB5 null mice, and yet, recombinant GPHB5 protein was able to stimulate energy expenditure and reduce adiposity. Taken together, these results provided the strong proof that GPHB5 is the “missing” intermediary hormone linking testosterone (and aging) and its well-known catabolic effect on adipose tissue.
Gengmiao Xiao, Aijun Qian, Zhuo Gao, Tingting Dai, Hui Liang, Shuai Wang, Mulan Deng, Yunjing Yan, Xindan Zhang, Xuedi Zhang, Yunping Mu, Jiqiu Wang, Aibo Gao, Huijie Zhang, Fanghong Li, Allan Zijian Zhao
Chordoma are rare malignant osseous neoplasms with a striking rate of recurrence. Primary chordomas typically originate from embryonic notochord remnants, whereas recurrent chordomas usually stem from tumor cells infiltrating bone or cartilage post-surgery. Clinically, the recurrent chordomas exhibit stiffer extracellular microenvironment (ECM) than primary tumors. Intriguingly, this study identified cytoskeleton rearrangement, stress fiber reorganization, enhanced stemness, and Notch signaling activation in recurrent chordoma tissues or cell lines surviving stiff substrates, indicating the critical roles of mechanical remodeling and tumor stemness in stiffness-resistance. We propose a novel recurrence model where tumor cells experience mechanoadaptive organization to resist stiff microenvironment-induced cell death. O-GlcNAcylation of Notch1 intracellular domain (NICD1) is central to this process. Mechanistically, the stiff ECM-driven ligand-independent phosphorylation of EPHA2 sequentially activates LYN kinase, and subsequently triggers OGT activity by phosphorylating Y989 and Y418, the newly revealed critical residues for OGT glycosyltransferase activity; this induces NICD1 O-GlcNAcylation at T2063, T2090, and S2162, specifically promoting transcription of mechanical and stemness-related genes. MIR31 deletion upregulates LYN, enhancing stiffness perception and tipping the balance toward O-GlcNAc addition to NICD1, finally resulting in mechanoadaptation- and tumor stemness-driven recurrence. Consequently, MIR31 deletion is a potential biomarker for recurrence and patient stratification in Notch- or OGT-targeted therapies.
Chengjie Lian, Weiyan Peng, Peiqiang Su, Yan Ye, Jialing Liu, Dongsheng Huang, Xuejuan Sun, Yi Pu, Zhiheng Liao, Xudong Wang, Zhu Qiu, Shanshan Wu, Lei Liu
MAP kinase kinase kinase kinase (MAP4K) family kinases are key kinases for T-cell-mediated immune responses; however, in vivo roles of MAP4K2 in immune regulation remain unclear. Using T-cell-specific Map4k2 conditional knockout (T-Map4k2 cKO) mice, single-cell RNA sequencing (scRNA-seq), and mass spectrometry analysis, we found that MAP4K2 interacted with DDX39B, induced forkhead box protein P3 (FOXP3) gene expression, and promoted Treg differentiation. Mechanistically, MAP4K2 directly phosphorylated the DEAD box protein DDX39B, leading to DDX39B nuclear translocation and subsequent Foxp3 RNA splicing. MAP4K2-induced FOXP3 mRNA levels were abolished in DDX39B knockout T cells. Furthermore, T-Map4k2 cKO mice displayed the reduction of Treg population and the sustained inflammation during remission phase of EAE autoimmune disease model. Remarkably, the anti-PD-1 immunotherapeutic effect on pancreatic cancer was significantly improved in T-Map4k2 cKO mice, Treg-specific Map4k2-deficient mice, adoptively transferred chimeric mice, or MAP4K2-inhibitor-treated mice. Consistently, scRNA-seq analysis of human pancreatic patients showed increased MAP4K2 levels in infiltrating Treg cells. Collectively, MAP4K2 promotes Treg differentiation by inducing DDX39B nuclear translocation, leading to the attenuation of antitumor immunity.
Huai-Chia Chuang, Chia-Wen Wang, Chia-Hsin Hsueh, Yu-Zhi Xiao, Ching-Yi Tsai, Pu-Ming Hsu, Evelyn L. Tan, Hsien-Yi Chiu, Tse-Hua Tan
Lipodystrophy syndromes are marked by loss of adipose tissue (AT), which leads to insulin resistance and metabolic syndrome development. We identified a heterozygous nonsense variant in early B cell factor 2 (EBF2) (Chr8:26033143C>A, NM_022659.4: c.493G>T, p.E165X) in a patient with atypical partial lipodystrophy (PLD). The EBF family is crucial for the differentiation and function of various mesenchymal tissues. Through in vitro and in vivo disease models, we discovered that this variant limits adipocyte differentiation and hampers adipose tissue remodeling. Heterozygous knock-in (Ebf2E165X/+) mice showed restricted adipogenesis and defective extracellular matrix (ECM) remodeling during post-weaning and high-fat diet (HFD)-induced adipose tissue expansion. HFD caused abnormal adipocyte hypertrophy, decreased expression of adiponectin and leptin, and glucose intolerance in Ebf2E165X/+ mice. Furthermore, key mitochondrial genes involved in fatty acid metabolism and oxidation were specifically downregulated in the Ebf2E165X/+ adipose tissue. Our results suggest that EBF2 dysfunction driven by this nonsense variant drives disease pathology, establishing a connection between EBF2 disruption and an atypical form of lipodystrophy.
Maria C. Foss-Freitas, Donatella Gilio, Lynn Pais, Eric D. Buras, Romil Kaul Verma, Melanie O'Leary, Heidi L. Rehm, Carmen Glaze, Kathryn Russell, Andre Monteiro da Rocha, Adam Neidert, Patrick Seale, Miriam S. Udler, Elif A. Oral, Tae-Hwa Chun
HIV/SIV-specific CD8+ T cell responses are typically unable to control viral rebound following antiretroviral therapy (ART) interruption (ATI). To investigate whether enhancing the magnitude and activation of SIV-specific CD8+ T cells at the time of ATI can improve the immune interception of reactivating SIV infections we vaccinated SIVmac239-infected rhesus macaques (RMs) on ART, boosting immediately prior to ATI, with a nucleoside-unmodified mRNA vaccine expressing SIVmac239 Gag (mRNA/SIVgag) alone or in combination with Nef (mRNA/SIVnef) and Pol (mRNA/SIVpol). The mRNA/SIVgag vaccine was effective in boosting Gag-specific CD8+ T cells in blood and lymphoid tissues. Following ATI, the mRNA/SIV-Gag vaccine group showed a significant delay in time to measurable viral rebound compared to controls, and manifested lower plasma viral loads (PVL) for up to 6 weeks after rebound. Similarly, RMs that received mRNA/SIVgag, mRNA/SIVnef, and mRNA/SIVpol also manifested a delay in SIV rebound compared to controls, suggesting that boosting SIV-specific CD8+ T cells during ATI can enhance early immune targeting of reactivating SIV infections. However, viral control was not sustained long-term as PVLs were similar across vaccinees and controls by 24 weeks post-rebound, highlighting the need for adjunctive therapies to improve the durability of virologic control elicited by CD8+ T cell-targeting vaccines.
Were R. Omange, Benjamin D. Varco-Merth, Omo Fadeyi, Alejandra Marenco, Hiroshi Takata, Derick M. Duell, William D. Goodwin, Paula Armitage, Christine M. Fennessey, Emek Kose, Taina T. Immonen, Ewelina Kosmider, William J. Bosche, Randy Fast, Chris Homick, Kelli Oswald, Rebecca Shoemaker, Rachele Bochart, Rhonda MacAllister, Caralyn S. Labriola, Jeremy V. Smedley, Michael K. Axthelm, Paul T. Edlefsen, Brandon F. Keele, Jeffrey D. Lifson, Janina Gergen, Benjamin Petsch, Susanne Rauch, Louis J. Picker, Afam A. Okoye
Human genetic studies have repeatedly associated ADAMTS7 with atherosclerotic cardiovascular disease. Subsequent investigations in mice demonstrated that ADAMTS7 is proatherogenic and induced in response to vascular injury. However, the cell-specific mechanisms governing ADAMTS7 proatherogenicity remain unclear. To determine which vascular cell types express ADAMTS7, we interrogated single-cell RNA sequencing of human carotid atherosclerosis and found ADAMTS7 expression in smooth muscle cells (SMCs), endothelial cells (ECs), and fibroblasts. We subsequently created SMC- and EC-specific Adamts7 conditional knockout and transgenic mice. Conditional knockout of Adamts7 in either cell type does not reduce atherosclerosis, whereas transgenic induction in either cell type increases atherosclerosis. In SMC transgenic mice, this increase coincides with an expansion of lipid-laden SMC foam cells and a decrease in fibrous cap formation. RNA-sequencing in Adamts7 overexpressing SMCs revealed an upregulation of lipid genes typically assigned to macrophages. Mechanistically, ADAMTS7 increases SMC oxLDL uptake through CD36, whose expression is upregulated by PU.1. ATAC-seq and motif analysis revealed increased chromatin accessibility at AP-1 enriched regions, consistent with AP-1 dependent remodeling of PU.1-regulated lipid-handling loci. In summary, ADAMTS7 promotes atherosclerosis by driving SMC foam cell formation through an AP-1/PU.1/CD36 regulatory axis.
Allen Chung, Lauren E. Fries, Hyun-Kyung Chang, Huize Pan, Alexander C. Bashore, Karissa Shuck, Caio V. Matias, Juliana Gomez Pardo, Jordan S. Kesner, Hanying Yan, Mingyao Li, Robert C. Bauer
Atherosclerotic cardiovascular disease (ASCVD) remains a leading cause of death worldwide, with plaque instability being a major culprit. Phenotypic switching of vascular smooth muscle cells (VSMCs) is a central event in atherosclerosis, driving both plaque progression and stability, yet the underlying mechanisms are incompletely understood, limiting drug development targeting this process. Kinesin family member 13B (KIF13B) has been implicated in vascular biology, but its function in VSMCs is unknown. Here, we demonstrate that VSMC-specific deletion of Kif13b in mice overexpressing proprotein convertase subtilisin/kexin type 9 (PCSK9) exacerbates lesion development and impairs plaque stability, characterized by thinner fibrous caps and increased inflammation. Mechanistically, we identified that KIF13B facilitates the ubiquitination and proteasomal degradation of Krüppel-like factor 4 (KLF4) through the Potassium channel tetramerization domain containing 10 (KCTD10)-dependent pathway. This KIF13B/KCTD10 axis reduces KLF4 protein levels, thereby inhibiting the pro-inflammatory responses and fibroblast-like transition of VSMCs to preserve their contractile phenotype. Importantly, the adverse effects of Kif13b deficiency on atherogenesis were effectively rescued by the small-molecule KLF4 inhibitor Kenpaullone. Our results unveil a VSMC-specific atheroprotective role for KIF13B, define the KIF13B/KCTD10/KLF4 pathway as a key regulatory axis governing VSMC fate and plaque stability, and validate its therapeutic potential for treating advanced atherosclerosis.
Guolin Miao, Yufei Han, Jingxuan Chen, Yiran Liu, Ge Zhang, Shaotong Pei, Yinqi Zhao, Yitong Xu, Liwen Zheng, Zhaoling Li, Xiangru Liu, Sijing Shi, Xuya Kang, Yahan Liu, Ling Zhang, Wei Huang, Yuhui Wang, Junnan Tang, Erdan Dong, Xunde Xian
The PIM kinase family is critically involved in tumorigenesis, yet its role in primary T cells is understudied. We reported that PIM2, distinct from the other two isoforms, inhibits T-cell responses to alloantigen. Here, we further established PIM2 as a key negative regulator in anti-tumor immunity. Pim2 deficiency in tumor antigen-specific or polyclonal T cells enhanced their ability to control tumor growth in murine breast cancer, melanoma and leukemia models. Pim2 deficiency enhanced cytokine production and metabolic activities in tumor-infiltrating CD8 T cells. Pim2 deficiency increased TCF1 expression and memory-like phenotype in CD8 T cells from lymphoid organs. Mechanistically, PIM2 facilitated LC3 lipidation, P62 degradation and autophagic flux in T cells, leading to impaired glycolysis and effector cytokine production. Furthermore, through modulating VPRBP kinase phosphorylation, PIM2 inhibited histone methyltransferase activity of EZH2 in CD8 T cells, causing disrupted memory-like phenotype. Notably, the PIM2 inhibitor JP11646 markedly enhanced antitumor T-cell response. The immunosuppressive role of PIM2 was validated in human T cells, where inhibition of PIM2 enhanced antitumor responses in engineered human T cells including melanoma-specific TCR-T cells and CD19CAR-T cells. Collectively, PIM2 represents a promising target for improving cancer immunotherapy through enhancing effector differentiation and persistence of CD8 T cells.
Yongxia Wu, Linlu Tian, Allison Pugel, Reza Alimohammadi, Qiao Cheng, Weiguo Cui, Michael I. Nishimura, Lauren E. Ball, Chien-Wei Lin, Shikhar Mehrotra, Andrew S. Kraft, Xue-Zhong Yu
Cellular senescence is a heterogeneous phenotype characterized primarily in mesenchymal cells, but the extent to which immune cells differ in their senescence phenotype, or “senotype”, is unclear. Here, we applied single-cell approaches alongside both global and cell-specific genetic senolytic mouse models to evaluate the senotype of immune cells in the bone marrow of aging mice. We found that myeloid-lineage cells exhibited the highest expression of p16 and senescence-associated secretory phenotype markers among all immune cell types. In contrast to clearance of p16+ senescent mesenchymal cells, targeted clearance of p16+ myeloid cells in aged mice only had minor effects on age-related bone loss in male mice, with no effects in females. In more detailed analyses, p16+ myeloid cells were only acutely cleared, being repopulated back to basal levels within a short time period. This led to a lack of long-lasting reduction in senescent cell burden, unlike when targeting bone mesenchymal cells. In vitro, myeloid-lineage cells differed markedly from mesenchymal cells in the development of a senescent phenotype. Collectively, our findings indicate that aged bone marrow myeloid cells do not achieve the fully developed senescent phenotype originally described in mesenchymal cells, justifying further characterization of senotypes of immune cells across tissues.
Madison L. Doolittle, Mitchell N. Froemming, Jennifer L. Rowsey, Ming Ruan, Leena Sapra, Joshua N. Farr, David G. Monroe, Sundeep Khosla
Glioblastoma (GBM) is a highly lethal brain tumor with limited treatment options and resistance to immune checkpoint inhibitors due to its immunosuppressive tumor microenvironment (TME). Here, we identify OLIG2 as a key regulator of immune evasion in GBM stem-like cells, inhibiting CD8+ T cell-dependent antitumor immunity, while promoting pro-tumor macrophages polarization. Mechanistically, OLIG2 recruits HDAC7 to repress CXCL10 transcription, inducing STAT3 activation in tumor-associated macrophages (TAMs) and decreasing CD8+ T cell infiltration and activation. Genetic deletion of OLIG2 significantly increases CXCL10 secretion, shifting TAMs toward an anti-tumor phenotype and enhancing CD8+ T cell activities. Furthermore, upregulated OLIG2 expression is correlated to resistance to immune checkpoint inhibitors (ICIs) in GBM patients. OLIG2 inhibition by either genetic deficiency or pharmacological targeting with CT-179 sensitizes GBM tumors to anti-PD-L1 therapy, enhancing antitumor immune responses and prolonging survival. Our findings reveal OLIG2+ glioma stem-like cells as critical mediators of immune evasion and identify the OLIG2/HDAC7/CXCL10 axis as a potential therapeutic target to enhance immune checkpoint inhibitors efficacy and to improve immunotherapy outcomes in aggressive GBM.
Xinchun Zhang, Jinjiang Xue, Cunyan Zhao, Chenqiuyue Zeng, Jiacheng Zhong, Gangfeng Yu, Xi Yang, Yao Ling, Dazhen Li, Jiaxiao Yang, Yun Xiu, Hongda Li, Shiyuan Hong, Liangjun Qiao, Song Chen, Q. Richard Lu, Yaqi Deng, Zhaohua Tang, Fanghui Lu
Atypical dopamine transporter (DAT) deficiency syndrome (DTDS) arises from genetic disruption of DAT function and is characterized by early-onset parkinsonism alongside comorbid psychiatric symptoms. However, the underlying pathobiological processes are largely unknown. Here, we present a mouse model of atypical DTDS based on the patient-derived compound heterozygote genotype, DAT-I312F/D421N+/+. DAT-I312F/D421N+/+ mice exhibited markedly impaired DAT function, leading to widespread changes in dopamine homeostasis, including elevated extracellular dopamine levels, reduced tyrosine hydroxylase and dopamine D1/D2 receptor expression, and decreased evoked dopamine release, mechanistically linked to enhanced tonic D2 autoreceptor inhibition. Fiber photometry measurements revealed disrupted fast striatal dopamine release dynamics, while confocal imaging showed reduced striatal dopaminergic axon fiber density. These neurochemical changes were accompanied by a psychomotor phenotype characterized by hyperlocomotion, enhanced exploration and pronounced clasping. Both amphetamine and anticholinergic treatment ameliorated the aberrant hyperactivity. Notably, amphetamine-induced dopamine release was profoundly blunted in ventral striatum but largely preserved in dorsal striatum, implicating region-specific dopamine release dynamics as a determinant of divergent behavioral and pharmacological responses. Summarized, our findings uncover multiscale dopamine dysfunction that links presynaptic DAT impairment to synaptic and circuit-level disruptions, offering insight into atypical DTDS and the co-occurrence of movement and psychiatric features.
Freja Herborg, Lisa K. Konrad, Søren H. Jørgensen, Jamila H. Lilja, Benoît Delignat-Lavaud, Leonie P. Posselt, Ciara F. Pugh, Sofie A. Bach, Cecilia F. Ratner, Nora Awadallah, Jose A. Pino, Frida Berlin, Aske L. Ejdrup, Mikkel V. Olesen, Mattias Rickhag, Birgitte Holst, Susana Aznar, Felix P. Mayer, David Woldbye, Gonzalo E. Torres, Louis-Eric Trudeau, Ulrik Gether
Prostate cancer (PCa) is one of the most frequently diagnosed malignancies and the main cause of cancer-related death in men worldwide. Poly (ADP-ribose) polymerase (PARP) inhibitors have been approved for the treatment of PCa harboring BRCA1/2 mutations. While the survival benefits conferred by PARP inhibitors (PARPi) may extend beyond this specific patient population based on evidence from recent clinical trials, the underlying mechanisms remain unexplored. Here, we demonstrate that PARPi substantially restore natural killer (NK) cell functions by promoting cyclophilin A (CypA) secretion from PCa cells, which correlates with improved prognosis in PCa patients from our and public cohorts. Mechanistically, tumor-derived CypA specifically from PCa cells binds to ANXA6 and activates the downstream FPR1 signaling pathway, leading to increased mitochondrial oxidative phosphorylation and NK cell activation. Pharmacological inhibition of CypA blocks the FPR1-AKT signaling and diminishes the cytotoxic effects of NK cells, thereby compromising the therapeutic efficacy of PARPi against PCa. Conversely, combining NK cell adoptive transfer therapy with PARPi markedly prolongs survival in mice bearing PCa. Collectively, we reveal a unique secretory crosstalk between PCa cells and NK cells induced by PARPi and propose a promising strategy for treating PCa.
Zheng Chao, Le Li, Xiaodong Hao, Hao Peng, Yanan Wang, Chunyu Zhang, Xiangdong Guo, Peikun Liu, Sheng Ma, Junbiao Zhang, Guanyu Qu, Yuzheng Peng, Zhengping Wei, Jing Luo, Bo Liu, Peixiang Lan, Zhihua Wang
How β-Catenin (βCat) mediates tissue hyperplasia is poorly understood. To explore this, we employed the adrenal cortex as a model system given its stereotypical spatial organization and the important role βCat plays in homeostasis and disease. For example, excessive production of aldosterone by the adrenal cortex (primary aldosteronism, PA) constitutes a major cause of cardiovascular morbidity and is associated with βCat gain-of-function (βCat-GOF). Adherens junctions (AJs) connect the actin cytoskeletons of adjacent zona Glomerulosa (zG) cells via a cadherin-βCat-α-Catenin complex and mediate aldosterone production. Whether βCat-GOF drives zG hyperplasia, a key feature of PA, via AJs is unknown. Here, we showed that aldosterone secretagogues (K+, AngII) and βCat-GOF mediated AJ formation via Rho/ROCK/actomyosin signaling. In addition, Rho/ROCK inhibition led to altered zG rosette morphology and decreased aldosterone production. Mice with zG-specific βCat-GOF demonstrated increased AJ formation and zG hyperplasia, which was blunted by Rho/ROCK inhibition and deletion of α-Catenin. βCat also impacted AJ formation independently of its role as a transcription factor. Furthermore, analysis of human aldosterone-producing adenomas revealed high levels of βCat expression were associated with increased membranous expression of K-Cadherin. Together, our findings identified Rho/ROCK signaling and αCat as key mediators of AJ formation and βCat-driven hyperplasia.
Mesut Berber, Betul Haykir, Nick A. Guagliardo, Vasileios Chortis, Kleiton Silva Borges, Paula Q. Barrett, Felix Beuschlein, Diana L. Carlone, David T. Breault