Protein aggregation is a hallmark of many neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS). Although mutations in TARDBP, encoding TDP-43, account for less than 1% of all ALS cases, TDP-43-positive aggregates are present in nearly all ALS patients, including patients with sporadic ALS (sALS) or carrying other familial ALS (fALS)-causing mutations. Interestingly, TDP-43 inclusions are also present in subsets of patients with frontotemporal dementia, Alzheimer’s disease, and Parkinson’s disease; therefore, methods of activating intracellular protein quality control machinery capable of clearing toxic cytoplasmic TDP-43 species may alleviate disease-related phenotypes. Here, we identify a novel function of Nemo-like kinase (Nlk) as a negative regulator of lysosome biogenesis. Genetic or pharmacological reduction of Nlk increased lysosome formation and improved clearance of aggregated TDP-43. Furthermore, Nlk reduction ameliorated pathological, behavioral, and lifespan deficits in two distinct mouse models of TDP-43 proteinopathy. Because many toxic proteins can be cleared along the autophagy-lysosome axis, targeted reduction of Nlk represents a potential approach to therapy development for multiple neurodegenerative disorders.
Leon Tejwani, Youngseob Jung, Hiroshi Kokubu, Sowmithra Sowmithra, Luhan Ni, Changwoo Lee, Benjamin Sanders, Paul J. Lee, Yangfei Xiang, Kimberly Luttik, Armand Soriano, Jennifer Yoon, Junhyun Park, Hannah H. Ro, Hyoungseok Ju, Clara Liao, Sofia Massaro Tieze, Frank Rigo, Paymaan Jafar-Nejad, Janghoo Lim
BACKGROUND. IgE-mediated anaphylaxis is a potentially fatal systemic allergic reaction for which there are no currently FDA-approved preventative therapies. Bruton’s tyrosine kinase (BTK) is an essential enzyme for IgE-mediated signaling pathways, and is an ideal pharmacologic target to prevent allergic reactions. In this open-label trial, we evaluated the safety and efficacy of acalabrutinib, a BTK inhibitor that is FDA-approved to treat some B cell malignancies, in preventing clinical reactivity to peanut in adults with peanut allergy. METHODS. After undergoing graded oral peanut challenge to establish their baseline level of clinical reactivity, 10 patients had a 6-week rest period, then received four standard doses of 100 mg acalabrutinib twice daily and underwent repeat food challenge. The primary endpoint was the change in patients’ threshold dose of peanut protein to elicit an objective clinical reaction. RESULTS. At baseline, patients tolerated a median of 29 mg of peanut protein before objective clinical reaction. During subsequent food challenge on acalabrutinib, patients’ median tolerated dose significantly increased to 4,044 mg (range, 444 – 4,044 mg). Seven patients tolerated the maximum protocol amount (4,044 mg) of peanut protein with no clinical reaction, and the other 3 patients’ peanut tolerance increased between 32- and 217-fold. Three patients experienced a total of 4 adverse events that were considered to be possibly related to acalabrutinib; all events were transient and nonserious. CONCLUSION. Acalabrutinib pretreatment achieved clinically-relevant increases in patients’ tolerance to their food allergen, thereby supporting the need for larger, placebo-controlled trials. TRIAL REGISTRATION. ClinicalTrials.gov NCT05038904 FUNDING. AstraZeneca Pharmaceuticals, the Johns Hopkins Institute for Clinical and Translational Research, the Ludwig Family Foundation, and NIH grants AI143965 and AI106043.
Ragha V. Suresh, Collin Dunnam, Dhananjay Vaidya, Robert A. Wood, Bruce S. Bochner, Donald W. MacGlashan, Jr., Melanie C. Dispenza
Long-acting antiretroviral agents for pre-exposure prophylaxis (PrEP) represent a promising new alternative to daily oral regimens for HIV prevention. Lenacapavir (LEN) is a first-in-class long-acting capsid inhibitor approved for the treatment of HIV-1 infection. Here, we assessed the efficacy of LEN for PrEP using a single high-dose simian-human immunodeficiency virus (SHIV) rectal challenge macaque model. In vitro, LEN showed potent antiviral activity against SHIV, similar to HIV-1. In macaques, a single subcutaneous administration of LEN demonstrated dose proportional increases in and durability of drug plasma levels. A high-dose SHIV inoculum for the PrEP efficacy evaluation was identified via virus titration in untreated macaques. LEN-treated macaques were challenged with high-dose SHIV 7 weeks post drug administration and the majority remained protected from infection as confirmed by plasma PCR, cell-associated proviral DNA, and serology testing. Complete protection and superiority to the untreated group was observed among animals whose LEN plasma exposure exceeded its model-adjusted clinical efficacy target at the time of challenge. All infected animals had subprotective LEN concentrations and showed no emergent resistance. These data demonstrate effective SHIV prophylaxis in a stringent macaque model at clinically relevant LEN exposures and support the clinical evaluation of LEN for HIV PrEP in humans.
Elena Bekerman, Stephen R. Yant, Laurie A. VanderVeen, Derek Hansen, Bing Lu, William Rowe, Kelly Wei Wang, Christian Callebaut
CXCR7 is an atypical chemokine receptor that recruits β-arrestin (ARRB2) and internalizes into clathrin-coated intracellular vesicles where the complex acts as a scaffold for cytoplasmic kinase assembly and signal transduction. Here we report that CXCR7 was elevated in the majority of prostate cancer (PCa) with neuroendocrine features (NEPC). CXCR7 markedly induced mitotic spindle and cell cycle gene expression. Mechanistically, we identified Aurora Kinase A (AURKA), a key regulator of mitosis, as a novel target that was bound and activated by the CXCR7-ARRB2 complex. CXCR7 interacted with proteins associated with microtubules and Golgi, and as such, the CXCR7-ARRB2-containing vesicles trafficked along the microtubules to the pericentrosomal Golgi apparatus, where the complex interacted with AURKA. Accordingly, CXCR7 promoted PCa cell proliferation and tumor growth, which was mitigated by AURKA inhibition. In summary, our study reveals a critical role of CXCR7-ARRB2 in interacting and activating AURKA, which can be targeted by AURKA inhibitors to benefit a subset of patients with NEPC.
Galina Gritsina, Ka-wing Fong, Xiaodong Lu, Zhuoyuan Lin, Wanqing Xie, Shivani Agarwal, Dong Lin, Gary E. Schiltz, Himisha Beltran, Eva Corey, Colm Morrissey, Yuzhuo Wang, Jonathan C. Zhao, Maha Hussain, Jindan Yu
There is no vaccine to protect from cryptosporidiosis, a leading cause of diarrhea in infants in low and middle income countries. Here we comprehensively identified parasite antigens associated with protection from reinfection. A Cryptosporidium protein microarray was constructed by in vitro transcription and translation of 1761 C. parvum, C. hominis or C. meleagridis antigens, including proteins with a signal peptide and/or a transmembrane domain. Plasma IgG and/or IgA from Bangladeshi children longitudinally followed for cryptosporidiosis from birth to three years of age, identified 233 seroreactive proteins. Seven of these were associated with protection from reinfection. These included Cp23 and Cp17, Gp900 and four additional antigens (CpSMP1, CpMuc8, CpCorA and CpCCDC1). Infection in the first year of life however often resulted in no detectable antigen-specific antibody response, and antibody responses, when detected, were (i) specific to the infecting parasite genotype, and (ii) decayed in the months post-infection. In conclusion humoral immune responses against specific parasite antigens were associated with acquired immunity. While antibody decay over time and parasite genotype-specificity may limit natural immunity, this work serves as a foundation for antigen selection for vaccine design.
Carol A. Gilchrist, Joseph J. Campo, Jozelyn V. Pablo, Jennie Z. Ma, Andy Teng, Amit Oberai, Adam D. Shandling, Masud Alam, Mamun Kabir, Abu S.G. Faruque, Rashidul Haque, William A. Petri Jr.
Increasing studies have demonstrated that disease states of the endocrine or exocrine pancreas aggravate one another, which implies bi-directional blood flow between islets and exocrine cells. However, this is inconsistent with the current model of uni-directional blood flow, which is strictly from islets to exocrine tissues. This conventional model was first proposed in 1932 and it has never been revisited to date. Here, large-scale image capture was used to examine the spatial relationship between islets and blood vessels in the following species; human, monkey, pig, rabbit, ferret, and mouse. While some arterioles passed by or traveled through islets, the majority of islets had no association with them. Islets with direct contact with the arteriole were significantly larger in size and less in number than those without contact. Unique to the pancreas, capillaries directly branched out from the arterioles, and have been labeled as “small arterioles” in the past studies. Overall, the arterioles emerged to feed the pancreas regionally, not specifically targeting individual islets. Vascularizing the pancreas in this way may allow an entire downstream region of islets and acinar cells to be simultaneously exposed to changes in the blood levels of glucose, hormones and other circulating factors.
Adam A. Rizk, Michael P. Dybala, Khalil C. Rodriguez, Marjan Slak Rupnik, Manami Hara
The liver can fully regenerate after partial resection and its underlying mechanisms have been extensively studied. The liver can also rapidly regenerate after injury with most studies focusing on hepatocyte proliferation; however, how hepatic necrotic lesions during acute or chronic liver diseases are eliminated and repaired remains obscure. Here we demonstrated that monocyte-derived macrophages (MoMFs) were rapidly recruited to and encapsulate necrotic areas during immune-mediated liver injury, and this feature was essential in repairing necrotic lesions. At the early stage of injury, infiltrating MoMFs activated the JAG1-NOTCH2 axis to induce cell death-resistant SOX9+ hepatocytes near the necrotic lesions, which acted as a barrier from further injury. Subsequently, necrotic environment (hypoxia and dead cells) induced a cluster of C1q+MoMFs that promoted necrotic removal and liver repair, while Pdgfb+MoMFs activated hepatic stellate cells (HSCs) to express -smooth muscle actin and induce a strong contraction signal (YAP, pMLC) to squeeze and finally eliminate the necrotic lesions. In conclusion, MoMFs play a key role in repairing the necrotic lesions not only by removing necrotic tissues but also by inducing cell death resistant hepatocytes to form a perinecrotic capsule and by activating α-smooth actin expressing HSCs to facilitate necrotic lesion resolution.
Dechun Feng, Xiaogang Xiang, Yukun Guan, Adrien Guillot, Hongkun Lu, Chingwen Chang, Yong He, Hua Wang, Hongna Pan, Cynthia Ju, Sean P. Colgan, Frank Tacke, Xin Wei Wang, George Kunos, Bin Gao
Acute graft-versus-host disease (aGVHD) is a severe complication of allogeneic hematopoietic stem cell transplantation. Hematopoietic dysfunction accompanied by severe aGVHD, which may be caused by niche impairment, is a long-standing clinical problem. However, how the bone marrow (BM) niche is damaged in aGVHD hosts is poorly defined. To comprehensively address this question, we employed a haplo-MHC-matched transplantation aGVHD murine model and performed single-cell RNA sequencing of non-hematopoietic BM cells. Transcriptional analysis showed that BM mesenchymal stromal cells (BMSCs) were severely affected with a reduction in cell ratio, abnormal metabolism, compromised differentiation potential and defective hematopoietic supportive function, which were validated by functional assays. We found that ruxolitinib, a selective JAK1/2 inhibitor, ameliorated aGVHD-related hematopoietic dysfunction through direct effect on recipient BMSCs, resulting in improved proliferation ability, adipogenesis/osteogenesis potential, mitochondrial metabolism capacity and crosstalk with donor-derived hematopoietic stem/progenitor cells. By inhibiting the JAK2/STAT1 pathway, ruxolitinib maintained long-term improvement of aGVHD BMSC function. Additionally, ruxolitinib pretreatment in vitro primed BMSCs to better support donor-derived hematopoiesis in vivo. These observations in the murine model were validated in patient samples. Overall, our findings suggest that ruxolitinib can directly restore BMSC function via JAK2/STAT1 pathway and in turn, improve the hematopoietic dysfunction caused by aGVHD.
Yan Lin, Quan Gu, Shihong Lu, Zengkai Pan, Zining Yang, Yapu Li, Shangda Yang, Yanling Lv, Zhaofeng Zheng, Guohuan Sun, Fanglin Gou, Chang Xu, Xiangnan Zhao, Fengjiao Wang, Chenchen Wang, Shiru Yuan, Xiaobao Xie, Yang Cao, Yue Liu, Weiying Gu, Tao Cheng, Hui Cheng, Xiaoxia Hu
Exaggerated Type 2 immune responses play critical roles in the pathogenesis of a variety of diseases including asthma, allergy, and pulmonary fibrosis. Recent studies have highlighted the importance of innate type 2 immune responses and innate lymphoid 2 cells (ILC2s) in these disorders. However, the mechanisms that control the development of pulmonary innate type 2 responses (IT2IR) and the recruitment and/or activation of ILC2 cells are poorly understood. In mouse models of pulmonary IT2IR, we demonstrated that Phospholipid scramblase-1 (PLSCR1), a type II transmembrane protein that mediates bidirectional and non-specific translocation of phospholipids between the inner and outer leaflets of the plasma membrane, was a critical regulator of IT2IR in the lung. We further suggested that PLSCR1 bound to and physically interacted with CRTH2 (Chemoattractant receptor-homologous molecule expressed on TH2 cells), a G-protein-coupled receptor that is expressed on multiple immune cells and commonly used to identify ILC2 cells, and the effects of PLSCR1 on ILC2 activation and IT2IR were mediated via CRTH2-dependent mechanisms. Overall, our studies demonstrated that PLSCR1 played an essential role in the pathogenesis of ILC2 responses, providing critical insights into biology and disease pathogenesis and identifying targets that can be manipulated in attempts to control IT2IR in chronic diseases such as asthma.
Ashley Hernandez-Gutierrez, Sonoor Majid, Adam T. Eberle, Ashley S. Choi, Parand Sorkhdini, Dongqin Yang, Alina Yang, Carmelissa Norbrun, Chuan He, Chang-min Lee, Chun Geun Lee, Jack A. Elias, Yang Zhou
Since T-box transcription factors (TFs) T-BET and EOMES are necessary for initiation of NK cell development, their ongoing requirement for mature NK cell homeostasis, function, and molecular programming remains unclear. To address this, T-BET and EOMES were deleted in unexpanded primary human NK cells using CRISPR/Cas9. Deleting these TFs compromised in vivo anti-tumor response of human NK cells. Mechanistically, T-BET and EOMES were required for normal NK cell proliferation and persistence in vivo. NK cells lacking T-BET and EOMES also exhibited defective responses to cytokine stimulation. Single-cell RNA-sequencing revealed a specific T-box transcriptional program in human NK cells, which was rapidly lost following T-BET and EOMES deletion. Further, T-BET and EOMES deleted CD56bright NK cells acquired an ILCP-like profile with increased expression of ILC-3-associated TFs RORC and AHR, revealing a role of T-box TF in maintaining mature NK cell phenotypes and an unexpected role of suppressing alternative ILC lineages. Our study reveals the critical importance of sustained EOMES and T-BET expression to orchestrate mature NK cell function and identity.
Pamela Wong, Jennifer A. Foltz, Lily Chang, Carly C. Neal, Tony Yao, Celia C. Cubitt, Jennifer Tran, Samantha Kersting-Schadek, Sathvik X. Palakurty, Natalia Jaeger, David A. Russler-Germain, Nancy D. Marin, Margery Gang, Julia A. Wagner, Alice Y. Zhou, Miriam T. Jacobs, Mark Foster, Timothy Schappe, Lynne Marsala, Ethan McClain, Patrick Pence, Michelle Becker-Hapak, Bryan Fisk, Allegra A. Petti, Obi L. Griffith, Malachi Griffith, Melissa M. Berrien-Elliott, Todd A. Fehniger
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