Proinflammatory islet antigen reactive CD4 T cells are linked with response to alefacept in type 1 diabetes

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Abstract

Variation in the preservation of β cell function in clinical trials in type 1 diabetes (T1D) has emphasized the need to define biomarkers to predict treatment response. The T1DAL trial targeted T cells with alefacept (LFA-3-Ig) and demonstrated C-peptide preservation in ~30% of new onset T1D subjects. We analyzed islet antigen reactive (IAR) CD4 T cells in PBMC samples collected prior to treatment from alefacept- and placebo-treated subjects using flow cytometry and single cell RNA-sequencing. IAR CD4 T cells at baseline had heterogenous phenotypes. Transcript profiles formed phenotypic clusters of cells along a trajectory based on increasing maturation and activation, and T cell receptor (TCR) chains showed clonal expansion. Notably, the frequency of IAR CD4 T cells with a memory phenotype and a unique transcript profile (Cluster 3) were inversely correlated with C-peptide preservation in alefacept-, but not placebo-treated subjects. Cluster 3 cells had a proinflammatory phenotype characterized by expression of the transcription factor BHLHE40 and the cytokines GM-CSF and TNF-α, and shared TCR chains with effector memory-like clusters. Our results suggest IAR CD4 T cells as a potential baseline biomarker of response to therapies targeting the CD2 pathway and warrant investigation for other T cell-related therapies.

Authors

Elisa Balmas, Janice Chen, Alex K. Hu, Hannah A. DeBerg, Mario G. Rosasco, Vivian H. Gersuk, Elisavet Serti, Cate Speake, Carla J. Greenbaum, Gerald T. Nepom, Peter S. Linsley, Karen Cerosaletti

Skeletal phenotype amelioration in Mucopolysaccharidosis VI requires intervention at the earliest stages of postnatal development

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Abstract

Mucopolysaccharidosis VI (MPS VI) is a rare lysosomal disease arising from impaired function of the enzyme Arylsulfatase B (ARSB). This causes aberrant accumulation of dermatan sulfate, a glycosaminoglycan (GAG) abundant in cartilage. While clinical severity varies along with age at first symptom manifestation, MPS VI usually presents early and strongly affects the skeleton. Current enzyme replacement therapy (ERT) does not provide effective treatment for the skeletal manifestations of MPS VI. This lack of efficacy may be due to inability of ERT to reach affected cells, or irreversibility of disease. To address the question of reversibility of skeletal phenotypes, we generated a conditional by inversion (COIN) mouse model of MPS VI, ArsbCOIN/COIN, wherein Arsb is initially null and can be restored to wild type using Cre. We restored Arsb at different times during postnatal development, using a tamoxifen-dependent global Cre driver. By restoring Arsb at postnatal days 7, 21, and 56-70 (P7, P21, and P56-P70), we determined that skeletal phenotypes can be fully rescued if Arsb restoration occurs at P7, while only achieving partial rescue at P21, and no significant rescue at P56-70. This work has highlighted the importance of early intervention in MPS VI patients to maximize therapeutic impact.

Authors

Elizabeth Hwang-Wong, Gabrielle Amar, Nanditha Das, Xiaoli Zhang, Nina A. Aaron, Kirsten Gale, Nyanza J. Rothman, Massimo Fante, Andrew D. Baik, Ajay Bhargava, Arun D. Fricker, Michelle McAlister, Jeremy S. Rabinowitz, John Lees-Shepard, Kalyan Nannuru, Aris N. Economides, Katherine D. Cygnar

Virus-specific TRM cells of both donor and recipient origin reside in human kidney transplants

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Abstract

Tissue-resident lymphocytes (TRLs) are critical for local protection against viral pathogens in peripheral tissue. However, it is unclear if TRLs perform a similar role in transplanted organs under chronic immunosuppressed conditions. The present study aimed to characterize the TRL compartment in human kidney transplant nephrectomies and examine its potential role in antiviral immunity. The TRL compartment of kidney transplants contained diverse innate(-like) and adaptive TRL populations expressing the canonical residency markers CD69, CD103, and CD49a. Chimerism of donor and recipient cells was present in 43% of kidney transplants and occurred in all TRL subpopulations. Paired single-cell transcriptome and T-cell receptor (TCR) sequencing showed that donor and recipient tissue-resident memory T (TRM) cells exhibit striking similarities in their transcriptomic profiles and share numerous TCR clonotypes predicted to target viral pathogens. Virus dextramer staining further confirmed that CD8 TRM cells of both donor and recipient origin cexpress TCRs with specificities against common viruses, including CMV, EBV, BK polyomavirus, and influenza A. Overall, the study results demonstrate that a diverse population of TRLs resides in kidney transplants and offer compelling evidence that TRM cells of both donor and recipient origin reside within this TRL population and may contribute to local protection against viral pathogens.

Authors

Daphne M. Hullegie-Peelen, Hector Tejeda Mora, Dennis A. Hesselink, ERIC M.J. BINDELS, Thierry Paulus Pierre van den Bosch, Marian C. Clahsen-van Groningen, Marjolein Dieterich, Sebastiaan Heidt, Robert C. Minnee, Georges M.G.M. Verjans, Martin J. Hoogduijn, Carla C. Baan

Plasma cells in human pancreatic ductal adenocarcinoma secrete antibodies to self-antigens

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Abstract

Intratumoral B cell responses are associated with more favorable clinical outcomes in human pancreatic ductal adenocarcinoma (PDAC). However, the antigens driving these B cell responses are largely unknown. We sought to discover these antigens by using single-cell RNA sequencing (scRNA-Seq) and immunoglobulin (Ig) sequencing of tumor-infiltrating immune cells from seven primary PDAC samples. We identified activated T and B cell responses and evidence of germinal center reactions. Ig sequencing identified plasma cell (PC) clones expressing isotype-switched and hyper-mutated Igs, suggesting the occurrence of T cell-dependent B cell responses. We assessed the reactivity of 41 recombinant antibodies that represented the products of 235 PCs and 12 B cells toward multiple cell lines and PDAC tissues, and observed frequent staining of intracellular self-antigens. Three of these antigens were identified: the filamentous actin (F-actin), the nucleic protein, RUVBL2, and the mitochondrial protein, HSPD1. Antibody titers to F-actin and HSPD1 were significantly elevated in the plasma of PDAC patients (n=59) compared to healthy donors (n=61). Thus, PCs in PDAC produce auto-antibodies reacting with intracellular self-antigens, which may result from promotion of pre-existing, autoreactive B cell responses. These observations indicate that the chronic inflammatory microenvironment of PDAC can support the adaptive immune response.

Authors

Min Yao, Jonathan Preall, Johannes Yeh, Darryl J. Pappin, Paolo Cifani, Yixin Zhao, Sophia Shen, Philip Moresco, Brian He, Hardik Patel, Amber N. Habowski, Daniel A. King, Kara L. Raphael, Arvind Rishi, Divyesh V. Sejpal, Matthew Weiss, David Tuveson, Douglas T. Fearon

Calponin 2 regulates ketogenesis to mitigate acute kidney injury

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Abstract

Calponin 2 (CNN2) is a prominent actin stabilizer. It regulates fatty acid oxidation (FAO) by interacting with estrogen receptor 2 (ESR2) to determine kidney fibrosis. However, whether CNN2 is actively involved in acute kidney injury (AKI) remains unclear. Here, we report that CNN2 was induced in human and animal kidneys after AKI. Knockdown of CNN2 preserved kidney function, mitigated tubular cell death and inflammation, and promoted cell proliferation. Distinct from kidney fibrosis, proteomics showed that the key elements in the FAO pathway have few changes during AKI, but we identified that 3-hydroxymethylglutaryl-CoA synthase 2 (Hmgcs2), a rate-limiting enzyme of endogenous ketogenesis that promotes cell self-renewal, was markedly increased in CNN2 knockdown kidneys. The ketone bodies β-hydroxybutyrate and ATP production were increased in CNN2 knockdown mice. Mechanistically, CNN2 interacts with ESR2 to negatively regulate activities of mitochondrial sirtuin 5. Activated sirtuin 5 subsequently desuccinylates Hmgcs2 to produce energy for mitigating AKI. Understanding CNN2-mediated discrete fine-tuning of protein posttranslational modification is critical to optimize organ performance after AKI.

Authors

Yuan Gui, Zachary Palanza, Priya R. Gupta, Hanwen Li, Yuchen Pan, Yuanyuan Wang, Geneva R. Hargis, Donald L. Kreutzer, Yanlin Wang, Sheldon I. Bastacky, Yansheng Liu, Silvia Liu, Dong Zhou

The XIST lncRNA is a sex-specific reservoir of TLR7 ligands in SLE

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Abstract

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with a dramatic sex bias, affecting 9-times more women than men. Activation of toll-like receptor 7 (TLR7) by self-RNA is a central pathogenic process leading to aberrant production of type-I interferon (IFN) in SLE, but the specific RNA molecules that serve as TLR7 ligands have not been defined. We therefore sought to identify female-specific endogenous RNAs containing canonical TLR7 stimulatory motifs. By leveraging gene expression data and the known sequence specificity of TLR7, we identified the female-specific X-inactive specific transcript (XIST) long non-coding RNA as a uniquely rich source of TLR7 ligands in SLE. XIST RNA stimulated IFNα production by plasmacytoid DCs in a TLR7-dependent manner, and deletion of XIST diminished the ability of whole cellular RNA to activate TLR7. XIST levels were elevated in blood leukocytes from female SLE patients compared to controls, correlated positively with disease activity and the IFN signature, and were enriched in extracellular vesicles released from dying cells in vitro. Importantly, XIST was not IFN-inducible, suggesting that XIST is a driver, rather than a consequence of IFN in SLE. Our work suggests a novel role for XIST RNA as a female-specific danger signal underlying the sex bias in SLE.

Authors

Jonathan D. Crawford, Hong Wang, Daniela Trejo-Zambrano, Raffaello Cimbro, C. Conover Talbot Jr., Mekha A. Thomas, Ashley M. Curran, Alexander A. Girgis, John T. Schroeder, Andrea Fava, Daniel W. Goldman, Michelle Petri, Antony Rosen, Brendan Antiochos, Erika Darrah

Cancer-associated fibroblasts reuse cancer-derived lactate to maintain a fibrotic and immunosuppressive microenvironment in pancreatic cancer

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Abstract

Glycolysis is highly enhanced in Pancreatic ductal adenocarcinoma (PDAC) cells; thus, glucose restrictions are imposed on nontumor cells in the PDAC tumor microenvironment (TME). However, little is known about how such glucose competition alters metabolism and confers phenotypic changes in stromal cells in the TME. Here, we report that cancer-associated fibroblasts (CAFs) with restricted glucose availability utilize lactate from glycolysis-enhanced cancer cells as a fuel and exert immunosuppressive activity in the PDAC TME. The expression of lactate dehydrogenase A (LDHA), which regulates lactate production, was a poor prognostic factor for PDAC patients, and LDHA depletion suppressed tumor growth in a CAF-rich murine PDAC model. Coculture of CAFs with PDAC cells revealed that most of the glucose was taken up by the tumor cells and that CAFs consumed lactate via monocarboxylate transporter 1 to enhance proliferation through the TCA cycle. Moreover, lactate-stimulated CAFs upregulated IL6 expression and suppressed cytotoxic immune cell activity synergistically with lactate. Finally, the LDHA inhibitor FX11 reduced tumor growth and improved antitumor immunity in CAF-rich PDAC tumors. Our study provides new insights into crosstalk among tumor cells, CAFs, and immune cells mediated by lactate and offers therapeutic strategies for targeting LDHA enzymatic activity in PDAC cells.

Authors

Fumimasa Kitamura, Takashi Semba, Noriko Yasuda-Yoshihara, Kosuke Yamada, Akiho Nishimura, Juntaro Yamasaki, Osamu Nagano, Tadahito Yasuda, Atsuko Yonemura, Yilin Tong, Huaitao Wang, Takahiko Akiyama, Kazuki Matsumura, Norio Uemura, Rumi Itoyama, Luke Bu, Lingfeng Fu, Xichen Hu, Feng Wei, Kosuke Mima, Katsunori Imai, Hiromitsu Hayashi, Yo-ichi Yamashita, Yuji Miyamoto, Hideo Baba, Takatsugu Ishimoto

Features and protective efficacy of human monoclonal antibodies targeting Mycobacterium tuberculosis arabinomannan

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Abstract

A better understanding of the epitopes most relevant for antibody-mediated protection against tuberculosis (TB) remains a major knowledge gap. We have shown that human polyclonal IgG to the Mycobacterium tuberculosis (Mtb) surface glycan arabinomannan (AM) and related lipoarabinomannan (LAM) is protective against TB. To investigate the impact of AM epitope recognition and Fc-gamma receptor (FcgR)-binding on antibody functions against Mtb, we isolated a high-affinity human monoclonal antibody (mAb; P1AM25) to AM and show its binding to oligosaccharide (OS) motifs we previously found to be associated with in vitro functions of human polyclonal anti-AM IgG. Human IgG1 P1AM25, but not two other high-affinity human IgG1 anti-AM mAbs reactive with different AM OS motifs, enhanced Mtb phagocytosis by macrophages and reduced intracellular growth in an FcgR-dependent manner. P1AM25 in murine IgG2a, but neither murine IgG1 nor a non-FcgR-binding IgG, given intraperitoneally prior to and after aerosolized Mtb infection was protective in C57BL/6 mice. Moreover, we demonstrate the protective efficacy of human IgG1 P1AM25 in passive transfer with Mtb-infected FcgR-humanized mice. These data enhance our knowledge of the important interplay between both antibody epitope specificity and Fc effector functions in the defense against Mtb and could inform development strategies of vaccines against TB.

Authors

Yanyan Liu, Tingting Chen, Yongqi Zhu, Aisha Furey, Todd L. Lowary, John Chan, Stylianos Bournazos, Jeffrey V. Ravetch, Jacqueline M. Achkar

Regulatory factor X1 induces macrophage M1 polarization via promoting DNA demethylation in autoimmune inflammation

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Abstract

Abnormal macrophage polarization is generally present in autoimmune diseases. Overwhelming M1 macrophage activation promotes the continuous progression of inflammation, which is one of the vital reasons for the development of autoimmune diseases. However, the underlying mechanism is still unclear. Here we explore the function of RFX1 in macrophage polarization by constructing colitis and lupus-like mouse models. Both in vivo and in vitro experiments confirmed that RFX1 can promote M1 and inhibit M2 macrophage polarization. Besides, we also found that RFX1 promoted DNA demethylation of macrophage polarization-related genes by increasing APOBEC3A/Apobec3 expression. Noteworthily, we identified a potential RFX1 inhibitor, adenosine diphosphate (ADP), providing a potential strategy for treating autoimmune diseases.

Authors

Shuang Yang, Pei Du, Haobo Cui, Meiling Zheng, Wei He, Xiaofei Gao, Zhi Hu, Sujie Jia, Qianjin Lu, Ming Zhao

An aging-susceptible circadian rhythm controls cutaneous antiviral immunity

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Abstract

Aged skin is prone to viral infections, but the mechanisms responsible for this immunosenescent immune risk are unclear. We observed that aged murine and human skin expressed reduced antiviral proteins (AVPs) and circadian regulators including Bmal1 and Clock. Bmal1 and Clock were found to control rhythmic AVP expression in skin and such circadian-control of AVPs was diminished by disruption of immune cell interleukin 27 signaling and deletion of Bmal1/Clock genes in mouse skins, as well as siRNA-mediated knockdown of CLOCK in human primary keratinocytes. We found that treatment of circadian enhancing agents, nobiletin and SR8278, reduced infection of herpes simplex virus 1 (HSV1) in epidermal explants and human keratinocytes in a BMAL1/CLOCK-dependent manner. Circadian enhancing treatment also reversed susceptibility of aging murine skin and human primary keratinocytes to viral infection. These findings reveal an evolutionarily conserved and age-sensitive circadian regulation of cutaneous antiviral immunity, underscoring circadian restoration as an antiviral strategy in aging populations.

Authors

Stephen Kirchner, Vivian Lei, Paul T. Kim, Meera Patel, Jessica L. Shannon, David Corcoran, Dalton Hughes, Diana K. Waters, Kafui Dzirasa, Detlev Erdmann, Jörn Coers, Amanda S. MacLeod, Jennifer Y. Zhang