Beclin 1 (Becn1) is a key molecule of the autophagy pathway and has been implicated in cancer development. Due to the embryonic lethality of Becn1 homozygous deficient mice, the precise mechanisms and cell-type-specific role of Becn1 in the regulation of inflammation and tumor immunity remain elusive. Here, we report that myeloid-deficient Becn1 (Becn1ΔM) mice develop neutrophilia and hypersusceptible to LPS-induced septic shock, with a high risk of developing spontaneous precursor (pre)-B cell lymphoma with elevated expressions of immunosuppressive molecules PD-L1 and IL-10. Becn1 deficiency results in stabilization of neutrophil MEKK3, aberrant p38 activation, and neutrophil-B cell interaction through Cxcl9/Cxcr3 chemotaxis. Neutrophil-B cell interplay leads to activations of IL-21/STAT3/IRF1 and CD40L/ERK signaling, together regulates the programmed death ligand 1 (PD-L1) expression, and suppresses CD8+ T cell function. Ablation of p38 in Becn1ΔM mice prevents neutrophil-inflammation and B cell tumorigenesis. Importantly, low Becn1 expression in human neutrophils correlates with PD-L1 levels in pre-B ALL patients. Our findings have identified myeloid Becn1 as a therapeutic target of cancer immunity and immunotherapy for pre-B lymphomas.
Peng Tan, Lian He, Changsheng Xing, Jingrong Mao, Xiao Yu, Motao Zhu, Lixia Diao, Leng Han, Yubin Zhou, James M. You, Helen Y. Wang, Rong-Fu Wang
Systemic lupus erythematosus (SLE) is a devastating autoimmune disease, in which hyperactive T cells play a critical role. Understanding molecular mechanisms underlying the T cell hyperactivity will lead to identification of specific therapeutic targets. Serine/arginine-rich splicing factor (SRSF)1 is an essential RNA-binding protein which controls posttranscriptional gene expression. We have demonstrated that SRSF1 levels are aberrantly decreased in T cells from SLE patients and correlate with severe disease, yet the role of SRSF1 in T cell physiology and autoimmune disease is largely unknown. Here we show that T cell-restricted Srsf1-deficient mice develop systemic autoimmunity and lupus-nephritis. Mice exhibit increased frequencies of activated/effector T cells producing proinflammatory cytokines, and an elevated T cell activation gene signature. Mechanistically, we noted increased activity of the mechanistic target of rapamycin (mTOR) pathway and reduced expression of its repressor PTEN. The mTOR complex (mTORC)1 inhibitor rapamycin suppressed proinflammatory cytokine production by T cells and alleviated autoimmunity in Srsf1-deficient mice. Of direct clinical relevance, PTEN levels correlated with SRSF1 in T cells from SLE patients, and SRSF1 overexpression rescued PTEN, suppressed mTORC1 activation and proinflammatory cytokine production. Our studies reveal the role of a previously unrecognized molecule SRSF1 in restraining T cell activation and averting the development of autoimmune disease and a potential therapeutic target for lupus.
Takayuki Katsuyama, Hao Li, Denis Comte, George C. Tsokos, Vaishali R. Moulton
Treatment of tumors with ionizing radiation stimulates an antitumor immune response partly dependent on induction of IFNs. These IFNs directly enhance dendritic cell and CD8+ T cell activity. Here we show that resistance to an effective antitumor immune response is also a result of IFN signaling in a different cellular compartment of the tumor, the cancer cells themselves. We abolished type I IFN signaling in cancer cells by genetic elimination of its receptor, IFNAR1. Pronounced immune responses were provoked after ionizing radiation of tumors from 4 mouse cancer cell lines with Ifnar1 knockout. This enhanced response depended on CD8+ T cells and was mediated by enhanced susceptibility to T cell–mediated killing. Induction of Serpinb9 proved to be the mechanism underlying control of susceptibility to T cell killing after radiation. Ifnar1-deficient tumors had an augmented response to anti–PD-L1 immunotherapy with or without radiation. We conclude that type I IFN can protect cancer cells from T cell–mediated cytotoxicity through regulation of Serpinb9. This result helps explain why radiation of tumors can stimulate antitumor immunity yet also result in resistance. It further suggests potential targets for intervention to improve therapy and to predict responses.
Jianzhou Chen, Yunhong Cao, Bostjan Markelc, Jakob Kaeppler, Jenny A.F. Vermeer, Ruth J. Muschel
Inflammation plays a critical role in the development of severe neonatal morbidities. Myeloid-derived suppressor cells (MDSCs) were recently implicated in the regulation of immune responses in newborns. Here, we report that the presence of MDSCs and their functional activity in infants are closely associated with the maturity of newborns and the presence of lactoferrin (LF) in serum. Low amounts of MDSCs at birth predicted the development of severe pathology in preterm infants — necrotizing enterocolitis (NEC). In vitro treatment of newborn neutrophils and monocytes with LF converted these cells to MDSCs via the LRP2 receptor and activation of the NF-κB transcription factor. Decrease in the expression of LRP2 was responsible for the loss of sensitivity of adult myeloid cells to LF. LF-induced MDSCs (LF-MDSCs) were effective in the treatment of newborn mice with NEC, acting by blocking inflammation, resulting in increased survival. LF-MDSCs were more effective than treatment with LF protein alone. In addition to affecting NEC, LF-MDSCs demonstrated potent ability to control ovalbumin-induced (OVA-induced) lung inflammation, dextran sulfate sodium–induced (DSS-induced) colitis, and concanavalin A–induced (ConA-induced) hepatitis. These results suggest that cell therapy with LF-MDSCs may provide potent therapeutic benefits in infants with various pathological conditions associated with dysregulated inflammation.
Yufeng Liu, Michela Perego, Qiang Xiao, Yumei He, Shuyu Fu, Juan He, Wangkai Liu, Xing Li, Yanlai Tang, Xiaoyu Li, Weiming Yuan, Wei Zhou, Fan Wu, Chunhong Jia, Qiliang Cui, George S. Worthen, Erik A. Jensen, Dmitry I. Gabrilovich, Jie Zhou
Electronic nicotine delivery systems (ENDS) or e-cigarettes have emerged as a popular recreational tool among adolescents and adults. Although the use of ENDS is often promoted as a safer alternative to conventional cigarettes, few comprehensive studies have assessed the long-term effects of vaporized nicotine and its associated solvents, propylene glycol (PG) and vegetable glycerin (VG). Here, we show that compared with smoke exposure, mice receiving ENDS vapor for 4 months failed to develop pulmonary inflammation or emphysema. However, ENDS exposure, independent of nicotine, altered lung lipid homeostasis in alveolar macrophages and epithelial cells. Comprehensive lipidomic and structural analyses of the lungs revealed aberrant phospholipids in alveolar macrophages and increased surfactant-associated phospholipids in the airway. In addition to ENDS-induced lipid deposition, chronic ENDS vapor exposure downregulated innate immunity against viral pathogens in resident macrophages. Moreover, independent of nicotine, ENDS-exposed mice infected with influenza demonstrated enhanced lung inflammation and tissue damage. Together, our findings reveal that chronic e-cigarette vapor aberrantly alters the physiology of lung epithelial cells and resident immune cells and promotes poor response to infectious challenge. Notably, alterations in lipid homeostasis and immune impairment are independent of nicotine, thereby warranting more extensive investigations of the vehicle solvents used in e-cigarettes.
Matthew C. Madison, Cameron T. Landers, Bon-Hee Gu, Cheng-Yen Chang, Hui-Ying Tung, Ran You, Monica J. Hong, Nima Baghaei, Li-Zhen Song, Paul Porter, Nagireddy Putluri, Ramiro Salas, Brian E. Gilbert, Ilya Levental, Matthew J. Campen, David B. Corry, Farrah Kheradmand
The transcription factor B Cell CLL/Lymphoma 11B (BCL11B) is indispensable for T lineage development of lymphoid progenitors. Here we show that chimeric antigen receptor (CAR) expression early in ex vivo generated lymphoid progenitors suppressed BCL11B, leading to suppression of T cell-associated gene expression and acquisition of natural killer (NK) cell-like properties. Upon adoptive transfer into hematopoietic stem cell transplant recipients they differentiated into CAR-induced killer cells (CARiK) that mediated potent antigen-directed antileukemic activity even across MHC barriers. A CD28 and active immune-receptor-tyrosine-based-activation-motifs were critical for a functional CARiK phenotype. These results give important insights into differentiation of murine and human lymphoid progenitors driven by synthetic CAR transgene-expression and encourage further evaluation of ex vivo generated CARiK cells for targeted immunotherapy.
Marcel Maluski, Arnab Ghosh, Jessica Herbst, Vanessa Scholl, Rolf Baumann, Jochen Huehn, Robert Geffers, Johann Meyer, Holger Maul, Britta Eiz-Vesper, Andreas Krueger, Axel Schambach, Marcel R.M. van den Brink, Martin G. Sauer
While a high frequency of Th1 cells in tumors is associated with improved cancer prognosis, this benefit has been attributed mainly to support of cytotoxic activity of CD8+ T cells. By attempting to potentiate antibody-driven immunity, we found a remarkable synergy between CD4+ T cells and tumor-binding antibodies. This surprising synergy was mediated by a small subset of tumor-infiltrating CD4+ T cells that express the high-affinity Fcγ receptor for IgG (FcγRI) in both mouse and human patients. These cells efficiently lyse tumor cells coated with antibodies through concomitant crosslinking of their T cell receptor (TCR) and FcγRI. By expressing FcγRI and its signaling chain in conventional CD4+ T cells, we successfully employed this mechanism to treat established solid cancers. Overall, this discovery sheds new light on the biology of this T cell subset, their function during tumor immunity, and the means to utilize their unique killing signals in immunotherapy.
Diana Rasoulouniriana, Nadine Santana-Magal, Amit Gutwillig, Leen Farhat-Younis, Yariv Wine, Corey Saperia, Lior Tal, Haim Gutman, Alexander Tsivian, Ronen Brenner, Eiman Abu Bandora, Nathan E. Reticker-Flynn, Peleg Rider, Yaron Carmi
Polymerase δ is essential for eukaryotic genome duplication and synthesizes DNA at both the leading and lagging strands. The polymerase δ complex is a heterotetramer comprising the catalytic subunit POLD1 and the accessory subunits POLD2, POLD3, and POLD4. Beyond DNA replication, the polymerase δ complex has emerged as a central element in genome maintenance. The essentiality of polymerase δ has constrained the generation of polymerase δ–knockout cell lines or model organisms and, therefore, the understanding of the complexity of its activity and the function of its accessory subunits. To our knowledge, no germline biallelic mutations affecting this complex have been reported in humans. In patients from 2 independent pedigrees, we have identified what we believe to be a novel syndrome with reduced functionality of the polymerase δ complex caused by germline biallelic mutations in POLD1 or POLD2 as the underlying etiology of a previously unknown autosomal-recessive syndrome that combines replicative stress, neurodevelopmental abnormalities, and immunodeficiency. Patients’ cells showed impaired cell-cycle progression and replication-associated DNA lesions that were reversible upon overexpression of polymerase δ. The mutations affected the stability and interactions within the polymerase δ complex or its intrinsic polymerase activity. We believe our discovery of human polymerase δ deficiency identifies the central role of this complex in the prevention of replication-related DNA lesions, with particular relevance to adaptive immunity.
Cecilia Domínguez Conde, Özlem Yüce Petronczki, Safa Baris, Katharina L. Willmann, Enrico Girardi, Elisabeth Salzer, Stefan Weitzer, Rico Chandra Ardy, Ana Krolo, Hanna Ijspeert, Ayca Kiykim, Elif Karakoc-Aydiner, Elisabeth Förster-Waldl, Leo Kager, Winfried F. Pickl, Giulio Superti-Furga, Javier Martínez, Joanna I. Loizou, Ahmet Ozen, Mirjam van der Burg, Kaan Boztug
Asthma is a heterogeneous syndrome that has been subdivided into physiological phenotypes and molecular endotypes. The most specific phenotypic manifestation of asthma is indirect airway hyperresponsiveness (AHR), and a prominent molecular endotype is the presence of type-2 inflammation. The underlying basis for type-2 inflammation and its relationship to AHR are incompletely understood. We assessed the expression of type-2 cytokines in the airways of subjects with and without asthma who were extensively characterized for AHR. Using quantitative morphometry of the airway wall, we identified a shift in mast cells from the submucosa to the airway epithelium specifically associated with both type-2 inflammation and indirect AHR. Using ex vivo modeling of primary airway epithelial cells in organotypic co-culture with mast cells, we have shown that epithelial-derived IL-33 uniquely induced type-2 cytokines in mast cells, which regulated the expression of epithelial IL33 in a feedforward loop. This feedforward loop was accentuated in epithelial cells derived from subjects with asthma. These results demonstrate that type-2 inflammation and indirect AHR in asthma are related to a shift in mast cell infiltration to the airway epithelium, and that mast cells cooperate with epithelial cells through IL-33 signaling to regulate type-2 inflammation.
Matthew C. Altman, Ying Lai, James D. Nolin, Sydney Long, Chien-Chang Chen, Adrian M. Piliponsky, William A. Altemeier, Megan Larmore, Charles W. Frevert, Michael S. Mulligan, Steven F. Ziegler, Jason S. Debley, Michael C. Peters, Teal S. Hallstrand
Sialyl Lewis A (sLeA, also known as CA19-9), a tetrasaccharide selectively and highly expressed on advanced adenocarcinomas including colon, stomach, and pancreatic cancers, has long been considered as an attractive target for active and passive vaccination. While progress in antibodies targeting tumor-associated protein antigens resulted in an impressive array of therapeutics for cancer treatment, similar progress in exploiting tumor-associated carbohydrate antigens, such as sLeA, has been hampered by the lack of a detailed understanding of the singular characteristics of these antigens. We have addressed this issue by analyzing antibodies derived from patients immunized with an sLeA/KLH vaccine. These antibodies were engineered to mediate tumor clearance in vivo in preclinical models through Fc-FcγR interactions. However, in contrast to protein antigens in which hFcγRIIIA engagement was both necessary and sufficient to mediate tumor clearance in both preclinical and clinical settings, a similar selective dependence was not seen for anti-sLeA antibodies. Thus, re-engineering the Fc portion of sLeA-targeting antibodies to broadly enhance their affinity for activating FcγRs led to an enhanced therapeutic effect. These findings will facilitate the development of more efficient anticancer therapies and further advance this promising class of therapeutic antibodies into clinical use.
Polina Weitzenfeld, Stylianos Bournazos, Jeffrey V. Ravetch