Ectonucleotidase CD39-driven control of postinfarction myocardial repair and rupture

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Abstract

Mechanical complications of myocardial infarction (MI) are often fatal. Little is known about endogenous factors that predispose to myocardial rupture after MI. Ectonucleoside triphosphate diphosphohydrolase (CD39) could be a critical mediator of propensity to myocardial rupture after MI due to its role in modulating inflammation and thrombosis. Using a model of permanent coronary artery ligation, rupture was virtually abrogated in cd39^–/– mice versus cd39^+/+ controls, with elevated fibrin and collagen deposition and marked neutrophil and macrophage influx. Macrophages were found to display increased surface expression of CD301 and CD206, marking a reparative phenotype, driven by increased extracellular ATP and IL-4 in the infarcted myocardium of cd39^–/– mice. A myeloid-specific CD39-knockout mouse also demonstrated protection from rupture, with an attenuated rupture phenotype, suggesting that complete ablation of CD39 provides the greatest degree of protection in this model. Absence of CD39, either globally or in a myeloid lineage–restricted fashion, skews the phenotype toward alternatively activated (reparative) macrophage infiltration following MI. These studies reveal a previously unrecognized and unexpected role of endogenous CD39 to skew macrophage phenotype and promote a propensity to myocardial rupture after MI.

Authors

Nadia R. Sutton, Takanori Hayasaki, Matthew C. Hyman, Anuli C. Anyanwu, Hui Liao, Danica Petrovic-Djergovic, Linda Badri, Amy E. Baek, Natalie Walker, Keigo Fukase, Yogendra Kanthi, Scott H. Visovatti, Ellen L. Horste, Jessica J. Ray, Sascha N. Goonewardena, David J. Pinsky

Anti-SIRPα antibodies as a potential new tool for cancer immunotherapy

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Abstract

Tumor cells are thought to evade immune surveillance through interaction with immune cells. Much recent attention has focused on the modification of immune responses as a basis for new cancer treatments. SIRPα is an Ig superfamily protein that inhibits phagocytosis in macrophages upon interaction with its ligand CD47 expressed on the surface of target cells. Here, we show that SIRPα is highly expressed in human renal cell carcinoma and melanoma. Furthermore, an anti-SIRPα Ab that blocks the interaction with CD47 markedly suppressed tumor formation by renal cell carcinoma or melanoma cells in immunocompetent syngeneic mice. This inhibitory effect of the Ab appeared to be mediated by dual mechanisms: direct induction of Ab-dependent cellular phagocytosis of tumor cells by macrophages and blockade of CD47-SIRPα signaling that negatively regulates such phagocytosis. The antitumor effect of the Ab was greatly attenuated by selective depletion not only of macrophages but also of NK cells or CD8⁺ T cells. In addition, the anti-SIRPα Ab also enhances the inhibitory effects of Abs against CD20 and programmed cell death 1 (PD-1) on tumor formation in mice injected with SIRPα-nonexpressing tumor cells. Anti-SIRPα Abs thus warrant further study as a potential new therapy for a broad range of cancers.

Authors

Tadahiko Yanagita, Yoji Murata, Daisuke Tanaka, Sei-ichiro Motegi, Eri Arai, Edwin Widyanto Daniwijaya, Daisuke Hazama, Ken Washio, Yasuyuki Saito, Takenori Kotani, Hiroshi Ohnishi, Per-Arne Oldenborg, Noel Verjan Garcia, Masayuki Miyasaka, Osamu Ishikawa, Yae Kanai, Takahide Komori, Takashi Matozaki

Pentraxin-2 suppresses c-Jun/AP-1 signaling to inhibit progressive fibrotic disease

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Abstract

Pentraxin-2 (PTX-2), also known as serum amyloid P component (SAP/APCS), is a constitutive, antiinflammatory, innate immune plasma protein whose circulating level is decreased in chronic human fibrotic diseases. Here we show that recombinant human PTX-2 (rhPTX-2) retards progression of chronic kidney disease in Col4a3 mutant mice with Alport syndrome, reducing blood markers of kidney failure, enhancing lifespan by 20%, and improving histological signs of disease. Exogenously delivered rhPTX-2 was detected in macrophages but also in tubular epithelial cells, where it counteracted macrophage activation and was cytoprotective for the epithelium. Computational analysis of genes regulated by rhPTX-2 identified the transcriptional regulator c-Jun along with its activator protein–1 (AP-1) binding partners as a central target for the function of rhPTX-2. Accordingly, PTX-2 attenuates c-Jun and AP-1 activity, and reduces expression of AP-1–dependent inflammatory genes in both monocytes and epithelium. Our studies therefore identify rhPTX-2 as a potential therapy for chronic fibrotic disease of the kidney and an important inhibitor of pathological c-Jun signaling in this setting.

Authors

Naoki Nakagawa, Luke Barron, Ivan G. Gomez, Bryce G. Johnson, Allie M. Roach, Sei Kameoka, Richard M. Jack, Mark L. Lupher Jr., Sina A. Gharib, Jeremy S. Duffield

Early cytokine signatures of ischemia/reperfusion injury in human orthotopic liver transplantation

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Abstract

BACKGROUND. Orthotopic liver transplant (OLT) is the primary therapy for end-stage liver disease and acute liver failure. However, ischemia/reperfusion injury (IRI) can severely compromise allograft survival. To understand the evolution of immune responses underlying OLT-IRI, we evaluated longitudinal cytokine expression profiles from adult OLT recipients before transplant through 1 month after transplant.

METHODS. We measured the expression of 38 cytokines, chemokines, and growth factors in preoperative and postoperative recipient circulating systemic blood (before transplant and 1 day, 1 week, and 1 month after transplant) and intraoperative portal blood (before and after reperfusion) of 53 OLT patients and analyzed this expression in relation to biopsy-proven IRI (n = 26 IRI+; 27 IRI–), clinical liver function tests early (days 1–7) after transplant, and expression of genes encoding cytokine receptors in biopsies of donor allograft taken before and after reperfusion.

RESULTS. Bilirubin and arginine transaminase levels early after transplant correlated with IRI. Fourteen cytokines were significantly increased in the systemic and/or portal blood of IRI+ recipients that shifted from innate to adaptive-immune responses over time. Additionally, expression of cognate receptors for 10 of these cytokines was detected in donor organ biopsies by RNAseq.

CONCLUSION. These results provide a mechanistic roadmap of the early immunological events both before and after IRI and suggest several candidates for patient stratification, monitoring, and treatment.

FUNDING. Ruth L. Kirschstein National Research Service Award T32CA009120, Keck Foundation award 986722, and a Quantitative & Computational Biosciences Collaboratory Postdoctoral Fellowship.

Authors

Rebecca A. Sosa, Ali Zarrinpar, Maura Rossetti, Charles R. Lassman, Bita V. Naini, Nakul Datta, Ping Rao, Nicholas Harre, Ying Zheng, Roberto Spreafico, Alexander Hoffmann, Ronald W. Busuttil, David W. Gjertson, Yuan Zhai, Jerzy W. Kupiec-Weglinski, Elaine F. Reed

Tumor-infiltrating lymphocytes are dynamically desensitized to antigen but are maintained by homeostatic cytokine

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Abstract

T cells that enter tumors are largely tolerized, but how that process is choreographed and how the ensuing “dysfunctional” tumor-infiltrating lymphocytes (TILs) are maintained are poorly understood and are difficult to assess in spontaneous disease. We exploited an autochthonous model of breast cancer for high-resolution imaging of the early and later stages of tumor residence to understand the relationships between cellular behaviors and cellular phenotypes. “Dysfunctional” differentiation began within the first days of tumor residence with an initial phase in which T cells arrest, largely on tumor-associated macrophages. Within 10 days, cellular motility increased and resembled a random walk, suggesting a relative absence of TCR signaling. We then studied the concurrent and apparently contradictory phenomenon that many of these cells express molecular markers of activation and were visualized undergoing active cell division. We found that whereas proliferation did not require ongoing TCR/ZAP70 signaling, instead this is driven in part by intratumoral IL-15 cytokine. Thus, TILs undergo sequential reprogramming by the tumor microenvironment and are actively retained, even while being antigen insensitive. We conclude that this program effectively fills the niche with ineffective yet cytokine-dependent TILs, and we propose that these might compete with new clones, when they arise.

Authors

Bijan Boldajipour, Amanda Nelson, Matthew F. Krummel

Tissue distribution and clonal diversity of the T and B cell repertoire in type 1 diabetes

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Abstract

The adaptive immune repertoire plays a critical role in type 1 diabetes (T1D) pathogenesis. However, efforts to characterize B cell and T cell receptor (TCR) profiles in T1D subjects have been largely limited to peripheral blood sampling and restricted to known antigens. To address this, we collected pancreatic draining lymph nodes (pLN), “irrelevant” nonpancreatic draining lymph nodes, peripheral blood mononuclear cells (PBMC), and splenocytes from T1D subjects (n = 18) and control donors (n = 9) as well as pancreatic islets from 1 T1D patient; from these tissues, we collected purified CD4⁺ conventional T cells (Tconv), CD4⁺ Treg, CD8⁺ T cells, and B cells. By conducting high-throughput immunosequencing of the TCR β chain (TRB) and B cell receptor (BCR) immunoglobulin heavy chain (IGH) on these samples, we sought to analyze the molecular signature of the lymphocyte populations within these tissues and of T1D. Ultimately, we observed a highly tissue-restricted CD4⁺ repertoire, while up to 24% of CD8⁺ clones were shared among tissues. We surveyed our data set for previously described proinsulin- and glutamic acid decarboxylase 65–reactive (GAD65-reactive) receptors, and interestingly, we observed a TRB with homology to a known GAD65-reactive TCR (clone GAD4.13) present in 7 T1D donors (38.9%), representing >25% of all productive TRB within Tconv isolated from the pLN of 1 T1D subject. These data demonstrate diverse receptor signatures at the nucleotide level and enriched autoreactive clones at the amino acid level, supporting the utility of coupling immunosequencing data with knowledge of characterized autoreactive receptors.

Authors

Howard R. Seay, Erik Yusko, Stephanie J. Rothweiler, Lin Zhang, Amanda L. Posgai, Martha Campbell-Thompson, Marissa Vignali, Ryan O. Emerson, John S. Kaddis, Dave Ko, Maki Nakayama, Mia J. Smith, John C. Cambier, Alberto Pugliese, Mark A. Atkinson, Harlan S. Robins, Todd M. Brusko

IFN-ε protects primary macrophages against HIV infection

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Abstract

IFN-ε is a unique type I IFN that is not induced by pattern recognition response elements. IFN-ε is constitutively expressed in mucosal tissues, including the female genital mucosa. Although the direct antiviral activity of IFN-ε was thought to be weak compared with IFN-α, IFN-ε controls Chlamydia muridarum and herpes simplex virus 2 in mice, possibly through modulation of immune response. We show here that IFN-ε induces an antiviral state in human macrophages that blocks HIV-1 replication. IFN-ε had little or no protective effect in activated CD4⁺ T cells or transformed cell lines unless activated CD4⁺ T cells were infected with replication-competent HIV-1 at a low MOI. The block to HIV infection of macrophages was maximal after 24 hours of treatment and was reversible. IFN-ε acted on early stages of the HIV life cycle, including viral entry, reverse transcription, and nuclear import. The protection did not appear to operate through known type I IFN-induced HIV host restriction factors, such as APOBEC3A and SAMHD1. IFN-ε–stimulated immune mediators and pathways had the signature of type I IFNs but were distinct from IFN-α in macrophages. IFN-ε induced significant phagocytosis and ROS, which contributed to the block to HIV replication. These findings indicate that IFN-ε induces an antiviral state in macrophages that is mediated by different factors than those induced by IFN-α. Understanding the mechanism of IFN-ε–mediated HIV inhibition through immune modulation has implications for prevention.

Authors

Carley Tasker, Selvakumar Subbian, Pan Gao, Jennifer Couret, Carly Levine, Saleena Ghanny, Patricia Soteropoulos, Xilin Zhao, Nathaniel Landau, Wuyuan Lu, Theresa L. Chang

Longitudinal PET imaging demonstrates biphasic CAR T cell responses in survivors

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Abstract

Clinical monitoring of adoptive T cell transfer (ACT) utilizes serial blood analyses to discern T cell activity. While useful, these data are 1-dimensional and lack spatiotemporal information related to treatment efficacy or toxicity. We utilized a human genetic reporter, somatostatin receptor 2 (SSTR2), and PET, to quantitatively and longitudinally visualize whole-body T cell distribution and antitumor dynamics using a clinically approved radiotracer. Initial evaluations determined that SSTR2-expressing T cells were detectable at low densities with high sensitivity and specificity. SSTR2-based PET was applied to ACT of chimeric antigen receptor (CAR) T cells targeting intercellular adhesion molecule-1, which is overexpressed in anaplastic thyroid tumors. Timely CAR T cell infusions resulted in survival of tumor-bearing mice, while later infusions led to uniform death. Real-time PET imaging revealed biphasic T cell expansion and contraction at tumor sites among survivors, with peak tumor burden preceding peak T cell burden by several days. In contrast, nonsurvivors displayed unrelenting increases in tumor and T cell burden, indicating that tumor growth was outpacing T cell killing. Thus, longitudinal PET imaging of SSTR2-positive ACT dynamics enables prognostic, spatiotemporal monitoring with unprecedented clarity and detail to facilitate comprehensive therapy evaluation with potential for clinical translation.

Authors

Yogindra Vedvyas, Enda Shevlin, Marjan Zaman, Irene M. Min, Alejandro Amor-Coarasa, Spencer Park, Susan Park, Keon-Woo Kwon, Turner Smith, Yonghua Luo, Dohyun Kim, Young Kim, Benedict Law, Richard Ting, John Babich, Moonsoo M. Jin

Akt and SHP-1 are DC-intrinsic checkpoints for tumor immunity

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Abstract

BM-derived DC (BMDC) are powerful antigen-presenting cells. When loaded with immune complexes (IC), consisting of tumor antigens bound to antitumor antibody, BMDC induce powerful antitumor immunity in mice. However, attempts to employ this strategy clinically with either tumor-associated DC (TADC) or monocyte-derived DC (MoDC) have been disappointing. To investigate the basis for this phenomenon, we compared the response of BMDC, TADC, and MoDC to tumor IgG-IC. Our findings revealed, in both mice and humans, that upon exposure to IgG-IC, BMDC internalized the IC, increased costimulatory molecule expression, and stimulated autologous T cells. In contrast, TADC and, surprisingly, MoDC remained inert upon contact with IC due to dysfunctional signaling following engagement of Fcγ receptors. Such dysfunction is associated with elevated levels of the Src homology region 2 domain–containing phosphatase-1 (SHP-1) and phosphatases regulating Akt activation. Indeed, concomitant inhibition of both SHP-1 and phosphatases that regulate Akt activation conferred upon TADC and MoDC the capacity to take up and process IC and induce antitumor immunity in vivo. This work identifies the molecular checkpoints that govern activation of MoDC and TADC and their capacity to elicit T cell immunity.

Authors

Yaron Carmi, Tyler R. Prestwood, Matthew H. Spitzer, Ian L. Linde, Jonathan Chabon, Nathan E. Reticker-Flynn, Nupur Bhattacharya, Hong Zhang, Xiangyue Zhang, Pamela A. Basto, Bryan M. Burt, Michael N. Alonso, Edgar G. Engleman

Low-dose IL-2 selectively activates subsets of CD4⁺ Tregs and NK cells

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Abstract

CD4⁺ regulatory T cells (CD4Tregs) play a critical role in the maintenance of immune tolerance and prevention of chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation. IL-2 supports the proliferation and survival of CD4Tregs and previous studies have demonstrated that IL-2 induces selective expansion of CD4Tregs and improves clinical manifestations of chronic GVHD. However, mechanisms for selective activation of CD4Tregs and the effects of low-dose IL-2 on other immune cells are not well understood. Using mass cytometry, we demonstrate that low concentrations of IL-2 selectively induce STAT5 phosphorylation in Helios⁺ CD4Tregs and CD56^brightCD16^– NK cells in vitro. Preferential activation and expansion of Helios⁺ CD4Tregs and CD56^brightCD16^– NK cells was also demonstrated in patients with chronic GVHD receiving low-dose IL-2. With prolonged IL-2 treatment for 48 weeks, phenotypic changes were also observed in Helios^– CD4Tregs. The effects of low-dose IL-2 therapy on conventional CD4⁺ T cells and CD8⁺ T cells were limited to increased expression of PD-1 on effector memory T cells. These studies reveal the selective effects of low-dose IL-2 therapy on Helios⁺ CD4Tregs and CD56^bright NK cells that constitutively express high-affinity IL-2 receptors as well as the indirect effects of prolonged exposure to low concentrations of IL-2 in vivo.

Authors

Masahiro Hirakawa, Tiago Matos, Hongye Liu, John Koreth, Haesook T. Kim, Nicole E. Paul, Kazuyuki Murase, Jennifer Whangbo, Ana C. Alho, Sarah Nikiforow, Corey Cutler, Vincent T. Ho, Philippe Armand, Edwin P. Alyea, Joseph H. Antin, Bruce R. Blazar, Joao F. Lacerda, Robert J. Soiffer, Jerome Ritz