Immunology
Abstract
Despite being the leading cause of childhood mortality, pediatric gliomas have been relatively understudied, and the repurposing of immunotherapies has not been successful. Whole transcriptome sequencing, single-cell sequencing, and sequential multiplex immunofluorescence were used to identify an immunotherapy strategy evaluated in multiple preclinical glioma models. MAPK-driven pediatric gliomas have a higher interferon signature relative to other molecular subgroups. Single-cell sequencing identified an activated and cytotoxic microglia population designated MG-Act in BRAF-fused MAPK-activated pilocytic astrocytoma (PA), but not in high-grade gliomas or normal brain. TIM3 is expressed on MG-Act and on the myeloid cells lining the tumor vasculature but not normal brain. TIM3 expression becomes upregulated on immune cells in the PA microenvironment and anti-TIM3 reprograms ex vivo immune cells from human PAs to a pro-inflammatory cytotoxic phenotype. In a genetically engineered murine model of MAPK-driven low-grade gliomas, anti-TIM3 treatment increased median survival over IgG and anti-PD1 treated mice. ScRNA sequencing data during the therapeutic window of anti-TIM3 demonstrates enrichment of the MG-Act population. The therapeutic activity of anti-TIM3 is abrogated in the CX3CR1 microglia knockout background. These data support the use of anti-TIM3 in clinical trials of pediatric low-grade MAPK-driven gliomas.
Authors
Shashwat Tripathi, Hinda Najem, Corey Dussold, Sebastian Pacheco, Ruochen Du, Moloud Sooreshjani, Lisa A. Hurley, James P. Chandler, Roger Stupp, Adam M. Sonabend, Craig M. Horbinski, Rimas V. Lukas, Joanne Xiu, Giselle Y. López, Theodore P. Nicolaides, Valerie Brown, Nitin R. Wadhwani, Sandi K. Lam, Charles David James, Ganesh Rao, Maria G. Castro, Amy B. Heimberger, Michael DeCuypere
Abstract
Inflammatory neuropathies, which include chronic inflammatory demyelinating polyneuropathy (CIDP) and Guillain Barré syndrome (GBS), result from autoimmune destruction of the PNS and are characterized by progressive weakness and sensory loss. CD4+ T cells play a key role in the autoimmune destruction of the PNS. Yet, key properties of pathogenic CD4+ T cells remain incompletely understood. Here, we used paired single-cell RNA-Seq (scRNA-Seq) and single-cell T cell receptor–sequencing (scTCR-Seq) of peripheral nerves from an inflammatory neuropathy mouse model to identify IL-21–expressing CD4+ T cells that were clonally expanded and multifunctional. These IL-21–expressing CD4+ T cells consisted of 2 transcriptionally distinct expanded cell populations, which expressed genes associated with T follicular helper (Tfh) and T peripheral helper (Tph) cell subsets. Remarkably, TCR clonotypes were shared between these 2 IL-21–expressing cell populations, suggesting a common lineage differentiation pathway. Finally, we demonstrated that IL-21 receptor–KO (IL-21R–KO) mice were protected from neuropathy development and had decreased immune infiltration into peripheral nerves. IL-21 signaling upregulated CXCR6, a chemokine receptor that promotes CD4+ T cell localization in peripheral nerves. Together, these findings point to IL-21 signaling, Tfh/Tph differentiation, and CXCR6-mediated cellular localization as potential therapeutic targets in inflammatory neuropathies.
Authors
Maryamsadat Seyedsadr, Madison F. Bang, Ethan C. McCarthy, Shirley Zhang, Ho-Chung Chen, Mahnia Mohebbi, Willy Hugo, Jason K. Whitmire, Melissa G. Lechner, Maureen A. Su
Abstract
NKT cells are innate-like T cells, recruited to the skin during viral infection, yet their contributions to long-term immune memory to viruses are unclear. We identified granzyme K, a product made by cytotoxic cells including NKT cells, is linked to induction of Th1-associated antibodies during primary dengue virus (DENV) infection in humans. We examined the role of NKT cells in vivo using DENV-infected mice lacking CD1d-dependent (CD1ddep) NKT cells. In CD1d-KO mice, Th1-polarized immunity and infection resolution were impaired, which was dependent on intrinsic NKT cell production of IFN-γ, since it was restored by adoptive transfer of WT but not IFN-γ-KO NKT cells. Furthermore, NKT cell deficiency triggered immune bias, resulting in higher levels of Th2-associated IgG1 than Th1-associated IgG2a, which failed to protect against a homologous DENV re-challenge and promoted antibody-dependent enhanced disease during secondary heterologous infections. Similarly, Th2-immunity, typified by a higher IgG4:IgG3 ratio, was associated with worsened human disease severity during secondary infections. Thus, CD1ddep NKT cells establish Th1 polarity during the early innate response to DENV, which promotes infection resolution, memory formation and long-term protection from secondary homologous and heterologous infections. These observations illustrate how early innate immune responses during primary infections can influence secondary infection outcomes.
Authors
Youngjoo Choi, Wilfried A.A. Saron, Aled O'Neill, Manouri Senanayake, Annelies Wilder-Smith, Abhay P.S. Rathore, Ashley L. St. John
Abstract
Delayed-type drug hypersensitivity reactions are major causes of morbidity and mortality. The origin, phenotype and function of pathogenic T cells across the spectrum of severity requires investigation. We leveraged recent technical advancements to study skin-resident memory T cells (TRM) versus recruited T cell subsets in the pathogenesis of severe systemic forms of disease, SJS/TEN and DRESS, and skin-limited disease, morbilliform drug eruption (MDE). Microscopy, bulk transcriptional profiling and scRNAseq + CITEseq + TCRseq supported in SJS/TEN clonal expansion and recruitment of cytotoxic CD8+ T cells from circulation into skin, along with expanded and non-expanded cytotoxic CD8+ skin TRM. Comparatively, MDE displayed a cytotoxic T cell profile in skin without appreciable expansion and recruitment of cytotoxic CD8+ T cells from circulation, implicating TRM as potential protagonists in skin-limited disease. Mechanistic interrogation in patients unable to recruit T cells from circulation into skin and in a parallel mouse model supported that skin TRM were sufficient to mediate MDE. Concomitantly, SJS/TEN displayed a reduced regulatory T cell (Treg) signature compared to MDE. DRESS demonstrated recruitment of cytotoxic CD8+ T cells into skin like SJS/TEN, yet a pro-Treg signature like MDE. These findings have important implications for fundamental skin immunology and clinical care.
Authors
Pranali N. Shah, George A. Romar, Artür Manukyan, Wei-Che Ko, Pei-Chen Hsieh, Gustavo A. Velasquez, Elisa M. Schunkert, Xiaopeng Fu, Indira Guleria, Roderick T. Bronson, Kevin Wei, Abigail H. Waldman, Frank R. Vleugels, Marilyn G. Liang, Anita Giobbie-Hurder, Arash Mostaghimi, Birgitta A.R. Schmidt, Victor Barrera, Ruth K. Foreman, Manuel Garber, Sherrie J. Divito
Abstract
Emerging evidence has linked the dysregulation of N6-methyladenosine (m6A) modification to inflammation and inflammatory diseases, but the underlying mechanism still needs investigation. Here, we found that high levels of m6A modification in a variety of hyperinflammatory states are p65-dependent because Wilms tumor 1–associated protein (WTAP), a key component of the “writer” complex, is transcriptionally regulated by p65, and its overexpression can lead to increased levels of m6A modification. Mechanistically, upregulated WTAP is more prone to phase separation to facilitate the aggregation of the writer complex to nuclear speckles and the deposition of m6A marks on transcriptionally active inflammatory transcripts, thereby accelerating the proinflammatory response. Further, a myeloid deficiency in WTAP attenuates the severity of LPS-induced sepsis and DSS-induced IBD. Thus, the proinflammatory effect of WTAP is a general risk-increasing mechanism, and interrupting the assembly of the m6A writer complex to reduce the global m6A levels by targeting the phase separation of WTAP may be a potential and promising therapeutic strategy for alleviating hyperinflammation.
Authors
Yong Ge, Rong Chen, Tao Ling, Biaodi Liu, Jingrong Huang, Youxiang Cheng, Yi Lin, Hongxuan Chen, Xiongmei Xie, Guomeng Xia, Guanzheng Luo, Shaochun Yuan, Anlong Xu
Abstract
Cytomegalovirus (CMV) is one of the most common and relevant opportunistic pathogens in immunocompromised individuals such as kidney transplant recipients (KTRs). The exact mechanisms underlying the disability of cytotoxic T cells to provide sufficient protection against CMV in immunosuppressed individuals have not been identified yet. Here, we performed in-depth metabolic profiling of CMV-specific CD8+ T cells in immunocompromised patients and show the development of metabolic dysregulation at the transcriptional, protein, and functional level of CMV-specific CD8+ T cells in KTRs with non-controlled CMV infection. These dysregulations comprise impaired glycolysis and increased mitochondrial stress, which is associated with an intensified expression of the nicotinamide adenine dinucleotide nucleotidase (NADase) CD38. Inhibiting NADase activity of CD38 reinvigorated the metabolism and improved cytokine production of CMV-specific CD8+ T cells. These findings were corroborated in a mouse model of CMV infection under conditions of immunosuppression. Thus, dysregulated metabolic states of CD8+ T cells could be targeted by inhibiting CD38 to reverse hypo-responsiveness in individuals who fail to control chronic viral infection.
Authors
Nils Mülling, Felix M. Behr, Graham A. Heieis, Kristina Boss, Suzanne van Duikeren, Floortje J. van Haften, Iris N. Pardieck, Esmé T.I. van der Gracht, Ward Vleeshouwers, Tetje C. van der Sluis, J. Fréderique de Graaf, Dominique M.B. Veerkamp, Kees L.M.C. Franken, Xin Lei, Lukas van de Sand, Sjoerd H. van der Burg, Marij J.P. Welters, Sebastiaan Heidt, Wesley Huisman, Simon P. Jochems, Martin Giera, Oliver Witzke, Aiko P.J. de Vries, Andreas Kribben, Bart Everts, Benjamin Wilde, Ramon Arens
Abstract
Tolerance of mouse kidney allografts arises in grafts that develop regulatory Tertiary Lymphoid Organs (rTLOs). scRNAseq data and adoptive transfer of alloreactive T cells post-transplant showed that cytotoxic CD8+ T cells are reprogrammed within the accepted graft to an exhausted/regulatory-like phenotype mediated by IFN-γ. Establishment of rTLOs was required since adoptive transfer of alloreactive T cells prior to transplantation results in kidney allograft rejection. Despite intragraft CD8+ cells with a regulatory phenotype, they were not essential for the induction and maintenance of kidney allograft tolerance since renal allotransplantation into CD8 KO recipients resulted in acceptance and not rejection. Analysis of scRNAseq data from allograft kidneys and malignant tumors identified similar regulatory-like cell types within the T cell clusters and trajectory analysis showed that cytotoxic CD8+ T cells are reprogrammed into an exhausted/regulatory-like phenotype intratumorally. Induction of cytotoxic CD8+ T cell dysfunction of infiltrating cells appears to be a beneficial mechanistic pathway that protects the kidney allotransplant from rejection through a process we call “defensive tolerance.” This pathway has implications for our understanding of allotransplant tolerance and tumor resistance to host immunity.
Authors
Takahiro Yokose, Edward S. Szuter, Ivy Rosales, Michael T. Guinn, Andrew S. Liss, Taisuke Baba, David A. Ruddy, Michelle Piquet, Jamil Azzi, A. Benedict Cosimi, Paul S. Russell, Joren C. Madsen, Robert B. Colvin, Alessandro Alessandrini
Abstract
In utero gene editing (IUGE) is a potential treatment for inherited diseases that cause pathology before or soon after birth. Preexisting immunity to adeno-associated virus (AAV) vectors and Cas9 endonuclease may limit postnatal gene editing. The tolerogenic fetal immune system minimizes a fetal immune barrier to IUGE. However, the ability of maternal immunity to limit fetal gene editing remains a question. We investigated whether preexisting maternal immunity to AAV or Cas9 impairs IUGE. Using a combination of fluorescent reporter mice and a murine model of a metabolic liver disease, we demonstrated that maternal anti-AAV IgG antibodies were efficiently transferred from dam to fetus and impaired IUGE in a maternal titer–dependent fashion. By contrast, maternal cellular immunity was inefficiently transferred to the fetus, and neither maternal cellular nor humoral immunity to Cas9 impaired IUGE. Using human umbilical cord and maternal blood samples collected from mid- to late-gestation pregnancies, we demonstrated that maternal-fetal transmission of anti-AAV IgG was inefficient in midgestation compared with term, suggesting that the maternal immune barrier to clinical IUGE would be less relevant at midgestation. These findings support immunologic advantages for IUGE and inform maternal preprocedural testing protocols and exclusion criteria for future clinical trials.
Authors
John S. Riley, Valerie L. Luks, Cara L. Berkowitz, Ana Maria Dumitru, Nicole J. Kus, Apeksha Dave, Pallavi Menon, Monique E. De Paepe, Rajan Jain, Li Li, Lorraine Dugoff, Christina Paidas Teefey, Mohamad-Gabriel Alameh, Philip W. Zoltick, William H. Peranteau
Abstract
Authors
Rick Kapur, John W. Semple, Alexander P.J. Vlaar
Abstract
Authors
Simon J. Cleary, Mark R. Looney
Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)