Distinct mechanisms govern populations of myeloid-derived suppressor cells in chronic viral infection and cancer

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Abstract

Myeloid-derived suppressor cells (MDSC) are major negative regulators of immune responses in cancer and chronic infections. It remains unclear if regulation of MDSC activity at different conditions is controlled by similar mechanisms. We compared MDSC in mice with cancer and lymphocytic choriomeningitis virus (LCMV) infection. Chronic LCMV infection caused the development of monocytic - M-MDSC but did not induce polymorphonuclear - PMN-MDSC. In contrast, both MDSC populations were present in cancer models. An acquisition of immune suppressive activity by PMN-MDSC in cancer was controlled by IRE1α and ATF6 pathways of the endoplasmic reticulum (ER) stress response. Abrogation of PMN-MDSC activity by blockade of the ER stress response resulted in increase in tumor-specific immune response and reduced tumor progression. In contrast, the ER stress response was dispensable for suppressive activity of M-MDSC in cancer and LCMV infection. Acquisition of immune suppressive activity by M-MDSC in spleens was mediated by IFN-γ signaling. However, it was dispensable for suppressive activity of M-MDSC in tumor tissues. Suppressive activity of M-MDSC in tumors was retained due to the effect of IL-6 present at high concentrations in tumor site. These results demonstrate disease and population-specific mechanisms of MDSC accumulation and need for targeting of different pathways to achieve inactivation of these cells.

Authors

Evgenii N. Tcyganov, Shino Hanabuchi, Ayumi Hashimoto, David Campbell, Gozde Kar, Timothy W.F. Slidel, Corinne Cayatte, Aimee Landry, Fernanda Pilataxi, Susana Hayes, Brian Dougherty, Kristin C. Hicks, Kathy Mulgrew, Chih-Hang A. Tang, Chih-Chi A. Hu, Wei Guo, Sergei Grivennikov, Mohammed-Alkhatim A. Ali, Jean-Christophe Beltra, E. John Wherry, Yulia Nefedova, Dmitry I. Gabrilovich

Calcium phosphate microcrystals in the renal tubular fluid accelerate chronic kidney disease progression

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Abstract

The western pattern diet is rich not only in fat and calorie but also in phosphate. Negative impacts of excessive fat and calorie intake on health are widely accepted, whereas potential harms of excessive phosphate intake are poorly recognized. Here we show the mechanism by which dietary phosphate damages the kidney. When phosphate intake was excessive relative to the functioning nephron number, circulating fibroblast growth factor-23 (FGF23), a hormone that increases phosphate excretion per nephron, was increased to maintain phosphate homeostasis. FGF23 suppressed phosphate reabsorption in renal tubules and thus raised the phosphate concentration in the tubular fluid. Once it exceeded a threshold, microscopic particles containing calcium phosphate crystals appeared in the tubular lumen, which damaged tubular cells through binding to Toll-like receptor-4 expressed on them. Persistent tubular damage induced interstitial fibrosis, reduced the nephron number, and further boosted FGF23 to trigger a deterioration spiral leading to progressive nephron loss. In humans, progression of chronic kidney disease (CKD) ensued when the serum FGF23 level exceeded 53 pg/mL. The present study identified the calcium phosphate particles in the renal tubular fluid as an effective therapeutic target to decelerate nephron loss during the course of aging and CKD progression.

Authors

Kazuhiro Shiizaki, Asako Tsubouchi, Yutaka Miura, Kinya Seo, Takahiro Kuchimaru, Hirosaka Hayashi, Yoshitaka Iwazu, Marina Miura, Batpurev Battulga, Nobuhiko Ohno, Toru Hara, Rina Kunishige, Mamiko Masutani, Keita Negishi, Kazuomi Kario, Kazuhiko Kotani, Toshiyuki Yamada, Daisuke Nagata, Issei Komuro, Hiroshi Itoh, Hiroshi Kurosu, Masayuki Murata, Makoto Kuro-o

TNFR2/14-3-3ε signaling complex instructs macrophage plasticity in inflammation and autoimmunity

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Abstract

TNFR1 and TNFR2 have received prominent attention because of their dominance in the pathogenesis of inflammation and autoimmunity. TNFR1 has been extensively studied and primarily mediates inflammation. TNFR2 remains far less studied, although emerging evidences demonstrate that TNFR2 plays an anti-inflammatory and immunoregulatory role in various conditions and diseases. Herein, we report that TNFR2 regulates macrophage polarization, a highly dynamic process controlled by largely unidentified intracellular regulators. Using biochemical co-purification and mass spectrometry approaches, we isolated the signaling molecule 14-3-3ε as a component of TNFR2 complexes in response to progranulin stimulation in macrophages. In addition, 14-3-3ε was essential for TNFR2 signaling-mediated regulation of macrophage polarization and switch. Both global and myeloid-specific deletion of 14-3-3ε resulted in exacerbated inflammatory arthritis and counteracted the protective effects of progranulin-mediated TNFR2 activation against inflammation and autoimmunity. TNFR2/14-3-3ε signaled through PI3K/Akt/mTOR to restrict NF-κB activation while simultaneously stimulating C/EBPβ activation, thereby instructing macrophage plasticity. Collectively, this study identifies 14-3-3ε as a previously-unrecognized vital component of the TNFR2 receptor complex and provides new insights into the TNFR2 signaling, particularly its role in macrophage polarization with therapeutic implications for various inflammatory and autoimmune diseases with activation of the TNFR2/14-3-3ε anti-inflammatory pathway.

Authors

Wenyu Fu, Wenhuo Hu, Young-Su Yi, Aubryanna Hettinghouse, Guodong Sun, Yufei Bi, Wenjun He, Lei Zhang, Guanmin Gao, Jody Liu, Kazuhito Toyo-oka, Guozhi Xiao, David B. Solit, Png Loke, Chuan-ju Liu

SLIT2/ROBO signaling in tumor-associated microglia/macrophages drives glioblastoma immunosuppression and vascular dysmorphia

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Abstract

SLIT2 is a secreted polypeptide that guides migration of cells expressing ROBO1&2 receptors. Herein, we investigated SLIT2/ROBO signaling effects in gliomas. In patients with glioblastoma (GBM), SLIT2 expression increased with malignant progression and correlated with poor survival and immunosuppression. Knockdown of SLIT2 in mouse glioma cells and patient derived GBM xenografts reduced tumor growth and rendered tumors sensitive to immunotherapy. Tumor cell SLIT2 knockdown inhibited macrophage invasion and promoted a cytotoxic gene expression profile, which improved tumor vessel function and enhanced efficacy of chemotherapy and immunotherapy. Mechanistically, SLIT2 promoted microglia/macrophage chemotaxis and tumor-supportive polarization via ROBO1&2-mediated PI3Kgamma activation. Macrophage Robo1&2 deletion and systemic SLIT2 trap delivery mimicked SLIT2 knockdown effects on tumor growth and the tumor microenvironment (TME), revealing SLIT2 signaling through macrophage ROBOs as a potentially novel regulator of the GBM microenvironment and immunotherapeutic target for brain tumors.

Authors

Luiz H. Geraldo, Yunling Xu, Laurent Jacob, Laurence Pibouin-Fragner, Rohit Rao, Nawal Maïssa, Maite Verreault, Nolwenn Lemaire, Camille Knosp, Corinne Lesaffre, Thomas Daubon, Joost Dejaegher, Lien Solie, Justine Rudewicz, Thomas Viel, Bertrand Tavitian, Steven De Vleeschouwer, Marc Sanson, Andreas Bikfalvi, Ahmed Idbaih, Qing Richard Lu, Flavia R.S. Lima, Jean-Leon Thomas., Anne Eichmann, Thomas Mathivet

Inflammatory cytokines TNFα and IL-17 enhance the efficacy of cystic fibrosis transmembrane conductance regulator modulators

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Abstract

Without CFTR-mediated HCO3- secretion, airway epithelia of newborns with cystic fibrosis (CF) produce an abnormally acidic airway surface liquid (ASL), and the decreased pH impairs respiratory host defenses. However, within a few months of birth, ASL pH increases to match that in non-CF airways. Although the physiological basis for the increase is unknown, this time-course matches the development of inflammation in CF airways. To learn whether inflammation alters CF ASL pH, we treated CF epithelia with TNFα and IL-17, two inflammatory cytokines that are elevated in CF airways. TNFα+IL-17 markedly increased ASL pH by upregulating pendrin, an apical Cl-/HCO3- exchanger. Moreover, when CF epithelia were exposed to TNFα+IL-17, clinically approved CFTR modulators further alkalinized ASL pH. As predicted by these results, in vivo data revealed a positive correlation between airway inflammation and CFTR modulator-induced improvement in lung function. These findings suggest that inflammation is a key regulator of HCO3- secretion in CF airways. Thus, they explain earlier observations that ASL pH increases after birth and indicate that for similar levels of inflammation, the pH of CF ASL is abnormally acidic. These results also suggest that a non-cell-autonomous mechanism, airway inflammation, is an important determinant of the response to CFTR modulators.

Authors

Tayyab Rehman, Philip H. Karp, Ping Tan, Brian J. Goodell, Alejandro A. Pezzulo, Andrew L. Thurman, Ian M. Thornell, Samantha L. Durfey, Michael E. Duffey, David A. Stoltz, Edward F. McKone, Pradeep K. Singh, Michael J. Welsh

Germline RUNX1 variation and predisposition to childhood acute lymphoblastic leukemia

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Abstract

Genetic alterations in the RUNX1 gene are associated with benign and malignant blood disorders, particularly of megakaryocyte and myeloid lineages. The role of RUNX1 in acute lymphoblastic leukemia (ALL) is less clear, particularly how germline genetic variation influences the predisposition to this type of leukemia. Sequencing 4,836 children with B-ALL and 1,354 cases of T-ALL, we identified 31 and 18 germline RUNX1 variants, respectively. RUNX1 variants in B-ALL consistently showed minimal damaging effects. By contrast, 6 T-ALL-related variants result in drastic loss of RUNX1 activity as a transcription activator in vitro. Ectopic expression of dominant-negative RUNX1 variants in human CD34+ cells repressed differentiation into erythroid, megakaryocytes, and T cells, while promoting myeloid cell development. Chromatin immunoprecipitation sequencing of T-ALL models showed distinctive patterns of RUNX1 binding by variant proteins. Further whole genome sequencing identified JAK3 mutation as the most frequent somatic genomic abnormality in T-ALL with germline RUNX1 variants. Co-introduction of RUNX1 variant and JAK3 mutation in hematopoietic stem and progenitor cells in mice gave rise to T-ALL with early T-cell precursor phenotype. Taken together, these results indicated that RUNX1 is an important predisposition gene for T-ALL and pointed to novel biology of RUNX1-mediated leukemogenesis in the lymphoid lineages.

Authors

Yizhen Li, Wentao Yang, Meenakshi Devidas, Stuart S. Winter, Chimene Kesserwan, Wenjian Yang, Kimberly P. Dunsmore, Colton Smith, Maoxiang Qian, Xujie Zhao, Ranran Zhang, Julie M. Gastier-Foster, Elizabeth A. Raetz, William L. Carroll, Chunliang Li, Paul P. Liu, Karen R. Rabin, Takaomi Sanda, Charles G. Mullighan, Kim E. Nichols, William E. Evans, Ching-Hon Pui, Stephen P. Hunger, David T. Teachey, Mary V. Relling, Mignon L. Loh, Jun J. Yang

Serine hydroxymethyltransferase 2 expression promotes tumorigenesis in rhabdomyosarcoma with 12q13-14 amplification

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Abstract

The 12q13-q14 chromosomal region is recurrently amplified in 25% of fusion-positive (FP) rhabdomyosarcoma (RMS) cases and is associated with a poor prognosis. To identify amplified oncogenes in FP RMS, we compared the size, gene composition and expression of 12q13-q14 amplicons in FP RMS with other cancer categories (glioblastoma multiforme, lung adenocarcinoma and liposarcoma) in which 12q13-q14 amplification frequently occurs. We uncovered a 0.2 Mb region that is commonly amplified across these cancers and includes CDK4 and six other genes that are overexpressed in amplicon-positive samples. Additionally, we identified a 0.5 Mb segment that is only recurrently amplified in FP RMS and includes four genes that are overexpressed in amplicon-positive RMS. Among these genes, only SHMT2 was overexpressed at the protein level in an amplicon-positive RMS cell line. SHMT2 knockdown in amplicon- positive RMS cells suppressed growth, transformation and tumorigenesis, whereas overexpression in amplicon-negative RMS cells promoted these phenotypes. High SHMT2 expression reduced sensitivity of FP RMS cells to SHIN1, a direct SHMT2 inhibitor, but sensitized cells to pemetrexed, an inhibitor of the folate cycle. In conclusion, our study demonstrated that SHMT2 contributes to tumorigenesis in FP RMS and that SHMT2 amplification predicts differential response to drugs targeting this metabolic pathway.

Authors

Thanh H. Nguyen, Prasantha L. Vemu, Gregory E. Hoy, Salah Boudjadi, Bishwanath Chatterjee, Jack F. Shern, Javed Khan, Wenyue Sun, Frederic G. Barr

Canonical features of human antibodies recognizing the influenza hemagglutinin trimer interface

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Abstract

Broadly reactive antibodies targeting the influenza A virus hemagglutinin (HA) head domain are thought to be rare and to require extensive somatic mutations or unusual structural features to achieve breadth against divergent HA subtypes. Here we describe common genetic and structural features of protective human antibodies from several individuals recognizing the trimer interface (TI) of the influenza A HA head, a recently identified site of vulnerability. We examined the sequence of TI-reactive antibodies, determined crystal structures for TI antibody-antigen complexes, and analyzed the contact residues of the antibodies on HA to discover common genetic and structural features of TI antibodies. Our data reveal that many TI antibodies are encoded by a light chain variable gene segment incorporating a shared somatic mutation. In addition, these antibodies have a shared acidic residue in the heavy chain despite originating from diverse heavy chain variable gene segments. These studies show that the TI region of influenza A HA is a major antigenic site with conserved structural features that are recognized by a common human B cell public clonotype. The canonical nature of this antibody-antigen interaction suggests that the TI epitope might serve as an important new target for structure-based vaccine design.

Authors

Seth J. Zost, Jinhui Dong, Iuliia M. Gilchuk, Pavlo Gilchuk, Natalie J. Thornburg, Sandhya Bangaru, Nurgun Kose, Jessica A. Finn, Robin Bombardi, Cinque Soto, Elaine C. Chen, Rachel S. Nargi, Rachel E. Sutton, Ryan P. Irving, Naveenchandra Suryadevara, Jonna B. Westover, Robert H. Carnahan, Hannah L. Turner, Sheng Li, Andrew B. Ward, James E. Crowe Jr.

Extracellular matrix protein laminin β1 regulates pain sensitivity and anxiodepression-like behaviors in mice

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Abstract

Patients with neuropathic pain often experience comorbid psychiatric disorders. Cellular plasticity in the anterior cingulate cortex (ACC) is assumed as a critical interface for pain perception and emotion. However, substantial efforts thus far are focused on intracellular mechanisms of plasticity rather than extracellular alterations that might trigger and facilitate intracellular changes. Laminin is a key element of extracellular matrix (ECM) consisting of one α-, β- and γ-chain and implicated in several pathophysiological processes. Here we showed that Laminin β1 (LAMB1) in ACC is significantly downregulated upon peripheral neuropathy. Knocking down ACC LAMB1 exacerbated pain sensitivity and induced anxiety and depression. Mechanistic analysis revealed that loss of LAMB1 causes actin dysregulation via interaction with integrin beta1 and subsequent Src-dependent RhoA/LIMK/cofilin pathway, leading to increased presynaptic transmitter release probability and abnormal postsynaptic spine remodeling, which in turn orchestrates structural and functional plasticity of pyramidal neurons and eventually results in pain hypersensitivity and anxiodepression. This study shed new light on the functional capability of ECM, LAMB1 in modulating pain plasticity and revealed a mechanism that conveys extracellular alterations to intracellular plasticity. Moreover, we identified cingulate LAMB1/integrin β1 as a promising therapeutic strategy for treatment of neuropathic pain and associated anxiodepression.

Authors

Zhen-Zhen Li, Wen-Juan Han, Zhi-Chuan Sun, Yun Chen, Jun-Yi Sun, Guo-Hong Cai, Wan-Neng Liu, Tao-Zhi Wang, Yang-Dan Xie, Hong-Hui Mao, Fei Wang, Sui-Bin Ma, Fu-Dong Wang, Rou-Gang Xie, Sheng-Xi Wu, Ceng Luo

The clear cell sarcoma functional genomic landscape

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Abstract

Clear Cell Sarcoma (CCS) is a deadly malignancy affecting adolescents and young adults. It is characterized by reciprocal translocations resulting in the expression of the chimeric EWSR1-ATF1 or EWSR1-CREB1 fusion proteins, driving sarcomagenesis. Besides these characteristics, CCS has remained genomically uncharacterized. Copy number analysis of human CCSs showed frequent amplifications of the MITF locus and chromosomes 7 and 8. Few alterations were shared with Ewing sarcoma or desmoplastic small round cell tumors, other EWSR1-rearranged tumors. Exome sequencing in mouse tumors generated by expressing EWSR1-ATF1 from the Rosa26 locus demonstrated no other repeated pathogenic variants. Additionally, we generated a new CCS mouse by Cre-loxP-induced chromosomal translocation between Ewsr1 and Atf1, resulting in copy number loss of chromosome 6 and chromosome 15 instability, including amplification of a portion syntenic with human chromosome 8, surrounding Myc. Additional experiments in the Rosa26 conditional model demonstrated that Mitf or Myc can contribute to sarcomagenesis. Copy number observations in human tumors and genetic experiments in mice render, for the first time, a functional landscape of the CCS genome. These data advance efforts to understand the biology of CCS with innovative models, in which we can eventually validate preclinical therapies, necessary to move toward longer and better survival of the young victims of this disease.

Authors

Emanuele Panza, Benjamin B. Ozenberger, Krystal M. Straessler, Jared J. Barrott, Li Li, Yanliang Wang, Mingchao Xie, Anne Boulet, Simon W. A. Titen, Clinton C. Mason, Alexander J. Lazar, Li Ding, Mario R. Capecchi, Kevin B. Jones