Stavrou et al. report that intrathecal injection of AAV9-miR871 silences overexpressed PMP22 — the cause of the demyelinating neuropathy Charcot-Marie-Tooth disease type 1A (CMT1A) — and provides therapeutic benefit in a model of CMT1A. The cover image shows a toluidine blue–stained femoral motor nerve from an AAV9-miR871–treated CMT1A mouse.
Mitohormesis defines the increase in fitness mediated by adaptive responses to mild mitochondrial stress. Tetracyclines inhibit not only bacterial but also mitochondrial translation, thus imposing a low level of mitochondrial stress to eukaryotic cells. We demonstrate in cell and germ-free mouse models, that tetracyclines induce a mild adaptive mitochondrial stress response (MSR), involving both the ATF4-mediated integrative stress response and type I interferon (IFN) signaling. To overcome the interferences of tetracyclines with the host microbiome, we identify tetracycline derivatives that have minimal antimicrobial activity, yet retain full capacity to induce the MSR, such as the lead compound, 9-tert-butyldoxycycline (9-TB). The MSR induced by Doxycycline (Dox) and 9-TB improves survival and disease tolerance against lethal influenza virus (IFV) infection when given preventively. 9-TB, unlike Dox, did not affect the gut microbiome and showed also encouraging results against IFV when given in a therapeutic setting. Tolerance to IFV infection is associated with the induction of genes involved in lung epithelial cell and cilia function, and with down-regulation of inflammatory and immune gene sets in lungs, liver, and kidneys. Mitohormesis induced by non-antimicrobial tetracyclines and the ensuing IFN response may dampen excessive inflammation and tissue damage during viral infections, opening innovative therapeutic avenues.
Adrienne Mottis, Terytty Y. Li, Gaby El Alam, Alexis Rapin, Elena Katsyuba, David Liaskos, Davide D'Amico, Nicola L. Harris, Mark C. Grier, Laurent Mouchiroud, Mark L. Nelson, Johan Auwerx
Plasmacytoid dendritic cell (pDC) is a professional type I interferon producer, which plays critical roles in the pathogenesis of autoimmune diseases. However, both genetic regulation of pDC function and their relationships with autoimmunity are largely undetermined. Here, we investigated the causality of NCF1 missense variant, which is one of the most significant associated risk variants for lupus, and found that the substitution from arginine (R) to histidine (H) at position 90 in NCF1 protein (NCF1 p.R90H) led to excessive activation of pDCs. Mechanism study demonstrated that p.R90H reduced the affinity of NCF1 to phospholipid, thereby impaired endosomal localization of NCF1. As NCF1 is a subunit of NOX2 complex, this impairment led to acidified endosomal pH and facilitated downstream TLR signaling. Consistently, the homozygous knock-in mice manifested aggravated lupus progression in a pDC dependent lupus model. More importantly, pharmaceutical intervention revealed that hydroxychloroquine (HCQ) could antagonize the detrimental function of NCF1 p.R90H in lupus model and systemic lupus erythematosus (SLE) samples, supporting that NCF1 p.R90H could be identified as a genetic biomarker for HCQ application. Therefore, our study provides insights into the genetic control of pDC function and paradigm for applying genetic variants to improve targeted therapy for autoimmune diseases.
Yao Meng, Jianyang Ma, Chao Yao, Zhizhong Ye, Huihua Ding, Can Liu, Jun Li, Guanhua Li, Yuke He, Jia Li, Zhihua Yin, Li Wu, Haibo Zhou, Nan Shen
Accurately identifying patients that respond to immunotherapy remains clinically challenging. A noninvasive method that can longitudinally capture information about immune cell function and assist in the early assessment of tumor responses is highly desirable for precision immunotherapy. Here, we show that positron emission tomography (PET) imaging using a granzyme B-targeted radiotracer, named 68Ga-grazytracer, can noninvasively and effectively predict tumor responses to immune checkpoint inhibitors and adoptive T-cell transfer therapy in multiple tumor models. 68Ga-grazytracer was designed and selected from several non-aldehyde peptidomimetic-based radiotracers and exhibited excellent in vivo metabolic stability and favorable targeting efficiency to granzyme B secreted by effector CD8+ T cells upon immune responses. 68Ga-grazytracer permits more sensitive discrimination of responders and non-responders than 18F-fluorodeoxyglucose, thereby distinguishing between tumor pseudoprogression and true progression upon immune checkpoint blockade therapy in mouse models with varying immunogenicity. In a preliminary clinical trial with five patients, no adverse event was observed after 68Ga-grazytracer injection, and clinical responses in cancer patients undergoing immunotherapy were favorably correlated with 68Ga-grazytracer PET results. These results highlight the potential of 68Ga-grazytracer PET for enhancing the clinical applications of granzyme B secretion-related immunotherapies by supporting early response assessment and precise patient stratification in a noninvasive and longitudinal manner.
Haoyi Zhou, Yanpu Wang, Hongchuang Xu, Xiuling Shen, Ting Zhang, Xin Zhou, Yuwen Zeng, Kui Li, Li Zhang, Hua Zhu, Xing Yang, Nan Li, Zhi Yang, Zhaofei Liu
Targeted protein degradation is a rapidly advancing and expanding therapeutic approach. Drugs that degrade GSPT1 via the CRL4CRBN ubiquitin ligase are a new class of cancer therapy in active clinical development with evidence of activity against acute myeloid leukemia in early phase trials. However, other than activation of the integrated stress response, the downstream effects of GSPT1 degradation leading to cell death are largely undefined, and no murine models are available to study these agents. We identified the domains of GSPT1 essential for cell survival and show that GSPT1 degradation leads to impaired translation termination, activation of the integrated stress response pathway, and TP53-independent cell death. CRISPR-Cas9 screens implicated decreased translation initiation as protective to GSPT1 degradation, suggesting that cells with higher levels of translation are more susceptible to GSPT1 degradation. We defined two Crbn amino acids that prevent Gspt1 degradation in mice, generated a knock-in mouse with alteration of these residues, and demonstrated the efficacy of GSPT1-degrading drugs in vivo with relative sparing of numbers and function of long-term hematopoietic stem cells. Our results provide a mechanistic basis for the use of GSPT1 degraders for the treatment of cancer, including TP53-mutant AML.
Rob S. Sellar, Adam S. Sperling, Mikołaj Słabicki, Jessica A. Gasser, Marie E. McConkey, Katherine A. Donovan, Nada Mageed, Dylan N. Adams, Charles Zou, Peter G. Miller, Ravi Kumar Dutta, Steffen Boettcher, Amy E. Lin, Brittany E. Sandoval, Vanessa A. Quevedo Barrios, Veronica Shkolnik, Jonas Koeppel, Elizabeth K. Henderson, Emma C. Fink, Lu Yang, Anthony K.N. Chan, Sheela Pangeni Pokharel, Erik J. Bergstrom, Rajan Burt, Namrata D. Udeshi, Steven A. Carr, Eric S. Fischer, Chun-Wei Chen, Benjamin L. Ebert
Human cytomegalovirus (HCMV) is the most common congenital infection and a leading cause of stillbirth, neurodevelopmental impairment, and pediatric hearing loss worldwide. Development of a maternal vaccine or therapeutic to prevent congenital HCMV has been hindered by limited knowledge of the immune responses that protect against HCMV transmission in utero. To identify protective antibody responses, we measured HCMV-specific IgG binding and anti-viral functions in paired maternal and cord blood sera from HCMV seropositive transmitting (n=41) and non-transmitting (n=40) mother-infant dyads identified via a large U.S.-based public cord blood bank. We found that high avidity IgG binding to HCMV and antibody-dependent cellular phagocytosis (ADCP) were associated with reduced risk of congenital HCMV infection. We also determined that HCMV-specific IgG activation of FcγRI and FcγRII was enhanced in non-transmitting dyads and that increased ADCP responses were mediated through both FcγRI and FcγRIIA expressed on human monocytes. These findings suggest that engagement of FcγRI/FcγRIIA and Fc effector functions including ADCP may protect against congenital HCMV infection. Taken together, these data can guide future prospective studies on immune correlates against cCMV transmission and inform HCMV vaccine and immunotherapeutic development.
Eleanor C. Semmes, Itzayana G. Miller, Courtney E. Wimberly, Caroline T. Phan, Jennifer A. Jenks, Melissa J. Harnois, Stella J. Berendam, Helen Webster, Jillian H. Hurst, Joanne Kurtzberg, Genevieve G. Fouda, Kyle M. Walsh, Sallie R. Permar
JCI This Month is a digest of the research, reviews, and other features published each month.
Next-generation sequencing (NGS) technology enables rapid, high-throughput sequencing of thousands of genes or even entire genomes. The speed and scale of these techniques makes them powerful tools in medicine, creating an opportunity to build and search deep genetic databases, refine diagnoses, and inform precision medicine approaches. In this series, designed by Ben H. Park, five reviews describe how NGS is revolutionizing clinical insights into disease. Wensel et al. compare key NGS methods for investigating the microbiome, emphasizing the need for careful study design and validation as these techniques become more widely adopted. Schuler et al. outline the capabilities and limitations of current genetic testing approaches and provide examples of clinical scenarios in which NGS was combined with other strategies to make a diagnosis. The contribution from Waarts et al. describes how NGS has contributed to the identification of targetable mutations in a range of cancers and discusses challenges to achieving maximal therapeutic benefit of targeted treatments. Halima et al. focus on high-throughput NGS approaches that are revealing the fundamental genetic processes that govern immunity, influencing how we design and implement cancer immunotherapy. Finally, Dang and Park’s review on circulating tumor DNA discusses the advantages of blood-based diagnosis as well as strategies to overcome technical limitations and improve detection of cancer in its earliest stages.
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