Research Article
Abstract
Osteolytic bone disease is a hallmark of multiple myeloma (MM). A significant fraction (~20%) of MM patients do not develop osteolytic lesions (OLs). The molecular basis for the absence of bone disease in MM is not understood. We combined PET-CT and gene expression profiling (GEP) of purified BM CD138+ MM cells from 512 newly diagnosed MM patients to reveal that elevated expression of cystatin M/E (CST6) was significantly associated with the absence of OL in MM. An enzyme-linked immunosorbent assay revealed a strong correlation between CST6 levels in BM serum/plasma and CST6 mRNA expression. Both recombinant CST6 protein and BM serum from patients with high CST6 significantly inhibited the activity of the osteoclast-specific protease cathepsin K and blocked osteoclast differentiation and function. Recombinant CST6 inhibited bone destruction in ex vivo and in vivo myeloma models. Single-cell RNA-Seq showed that CST6 attenuates polarization of monocytes to osteoclast precursors. Furthermore, CST6 protein blocks osteoclast differentiation by suppressing cathepsin-mediated cleavage of NF-κB/p100 and TRAF3 following RANKL stimulation. Secretion by MM cells of CST6, an inhibitor of osteoclast differentiation and function, suppresses osteolytic bone disease in MM and probably other diseases associated with osteoclast-mediated bone loss.
Authors
Dongzheng Gai, Jin-Ran Chen, James P. Stewart, Intawat Nookaew, Hasem Habelhah, Cody Ashby, Fumou Sun, Yan Cheng, Can Li, Hongwei Xu, Bailu Peng, Tarun K. Garg, Carolina Schinke, Sharmilan Thanendrarajan, Maurizio Zangari, Fangping Chen, Bart Barlogie, Frits van Rhee, Guido Tricot, John D. Shaughnessy Jr., Fenghuang Zhan
Abstract
A once-weekly oral dose of isoniazid and rifapentine for 3 months (3HP) is recommended by the CDC for treatment of latent tuberculosis infection (LTBI). The aim of this study is to assess 3HP-mediated clearance of M. tuberculosis bacteria in macaques with asymptomatic LTBI. Twelve Indian-origin rhesus macaques were infected with a low dose (~10 CFU) of M. tuberculosis CDC1551 via aerosol. Six animals were treated with 3HP and 6 were left untreated. The animals were imaged via PET/CT at frequent intervals. Upon treatment completion, all animals except 1 were coinfected with SIV to assess reactivation of LTBI to active tuberculosis (ATB). Four of 6 treated macaques showed no evidence of persistent bacilli or extrapulmonary spread until the study end point. PET/CT demonstrated the presence of significantly more granulomas in untreated animals relative to the treated group. The untreated animals harbored persistent bacilli and demonstrated tuberculosis (TB) reactivation following SIV coinfection, while none of the treated animals reactivated to ATB. 3HP treatment effectively reduced persistent infection with M. tuberculosis and prevented reactivation of TB in latently infected macaques.
Authors
Riti Sharan, Shashank R. Ganatra, Dhiraj K. Singh, Journey Cole, Taylor W. Foreman, Rajesh Thippeshappa, Charles A. Peloquin, Vinay Shivanna, Olga Gonzalez, Cheryl L. Day, Neel R. Gandhi, Edward J. Dick Jr., Shannan Hall-Ursone, Smriti Mehra, Larry S. Schlesinger, Jyothi Rengarajan, Deepak Kaushal
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects motor neurons. Mutations in the SPTLC1 subunit of serine palmitoyltransferase (SPT), which catalyzes the first step in the de novo synthesis of sphingolipids (SLs), cause childhood-onset ALS. SPTLC1-ALS variants map to a transmembrane domain that interacts with ORMDL proteins, negative regulators of SPT activity. We show that ORMDL binding to the holoenzyme complex is impaired in cells expressing pathogenic SPTLC1-ALS alleles, resulting in increased SL synthesis and a distinct lipid signature. C-terminal SPTLC1 variants cause peripheral hereditary sensory and autonomic neuropathy type 1 (HSAN1) due to the synthesis of 1-deoxysphingolipids (1-deoxySLs) that form when SPT metabolizes L-alanine instead of L-serine. Limiting L-serine availability in SPTLC1-ALS–expressing cells increased 1-deoxySL and shifted the SL profile from an ALS to an HSAN1-like signature. This effect was corroborated in an SPTLC1-ALS pedigree in which the index patient uniquely presented with an HSAN1 phenotype, increased 1-deoxySL levels, and an L-serine deficiency. These data demonstrate how pathogenic variants in different domains of SPTLC1 give rise to distinct clinical presentations that are nonetheless modifiable by substrate availability.
Authors
Museer A. Lone, Mari J. Aaltonen, Aliza Zidell, Helio F. Pedro, Jonas A. Morales Saute, Shalett Mathew, Payam Mohassel, Carsten G. Bönnemann, Eric A. Shoubridge, Thorsten Hornemann
Abstract
In addition to playing a major role in tumor cell biology, p53 generates a microenvironment that promotes antitumor immune surveillance via tumor-associated macrophages. We examined whether increasing p53 signaling in the tumor microenvironment influences antitumor T cell immunity. Our findings indicate that increased p53 signaling induced either pharmacologically with APR-246 (eprenetapopt) or in p53-overexpressing transgenic mice can disinhibit antitumor T cell immunity and augment the efficacy of immune checkpoint blockade. We demonstrated that increased p53 expression in tumor-associated macrophages induces canonical p53-associated functions such as senescence and activation of a p53-dependent senescence-associated secretory phenotype. This was linked with decreased expression of proteins associated with M2 polarization by tumor-associated macrophages. Our preclinical data led to the development of a clinical trial in patients with solid tumors combining APR-246 with pembrolizumab. Biospecimens from select patients participating in this ongoing trial showed that there was a suppression of M2-polarized myeloid cells and increase in T cell proliferation with therapy in those who responded to the therapy. Our findings, based on both genetic and a small molecule–based pharmacological approach, suggest that increasing p53 expression in tumor-associated macrophages reprograms the tumor microenvironment to augment the response to immune checkpoint blockade.
Authors
Arnab Ghosh, Judith Michels, Riccardo Mezzadra, Divya Venkatesh, Lauren Dong, Ricardo Gomez, Fadi Samaan, Yu-Jui Ho, Luis Felipe Campesato, Levi Mangarin, John Fak, Nathan Suek, Aliya Holland, Cailian Liu, Mohsen Abu-Akeel, Yonina Bykov, Hong Zhong, Kelly Fitzgerald, Sadna Budhu, Andrew Chow, Roberta Zappasodi, Katherine S. Panageas, Olivier de Henau, Marcus Ruscetti, Scott W. Lowe, Taha Merghoub, Jedd D. Wolchok
Abstract
Sudden cardiac death (SCD) in patients with heart failure (HF) is allied with an imbalance in reduction and oxidation (redox) signaling in cardiomyocytes; however, the basic pathways and mechanisms governing redox homeostasis in cardiomyocytes are not fully understood. Here, we show that cytochrome b5 reductase 3 (CYB5R3), an enzyme known to regulate redox signaling in erythrocytes and vascular cells, is essential for cardiomyocyte function. Using a conditional cardiomyocyte-specific CYB5R3-knockout mouse, we discovered that deletion of CYB5R3 in male, but not female, adult cardiomyocytes causes cardiac hypertrophy, bradycardia, and SCD. The increase in SCD in CYB5R3-KO mice is associated with calcium mishandling, ventricular fibrillation, and cardiomyocyte hypertrophy. Molecular studies reveal that CYB5R3-KO hearts display decreased adenosine triphosphate (ATP), increased oxidative stress, suppressed coenzyme Q levels, and hemoprotein dysregulation. Finally, from a translational perspective, we reveal that the high-frequency missense genetic variant rs1800457, which translates into a CYB5R3 T117S partial loss-of-function protein, associates with decreased event-free survival (~20%) in Black persons with HF with reduced ejection fraction (HFrEF). Together, these studies reveal a crucial role for CYB5R3 in cardiomyocyte redox biology and identify a genetic biomarker for persons of African ancestry that may potentially increase the risk of death from HFrEF.
Authors
Nolan T. Carew, Heidi M. Schmidt, Shuai Yuan, Joseph C. Galley, Robert Hall, Helene M. Altmann, Scott A. Hahn, Megan P. Miller, Katherine C. Wood, Bethann Gabris, Margaret C. Stapleton, Sean Hartwick, Marco Fazzari, Yijen L. Wu, Mohamed Trebak, Brett A. Kaufman, Charles F. McTiernan, Francisco J. Schopfer, Placido Navas, Patrick H. Thibodeau, Dennis M. McNamara, Guy Salama, Adam C. Straub
Abstract
Forkhead box O transcriptional factors, especially FoxO1 and FoxO3a, play critical roles in physiologic and pathologic immune responses. However, the function of FoxO4, another main member of the FoxO family, in lymphoid cells is still poorly understood. Here, we showed that loss of FoxO4 in T cells augmented IFN-γ production of Th1 cells in vitro. Correspondingly, conditional deletion of FoxO4 in CD4+ T cells enhanced T cell–specific responses to Listeria monocytogenes infection in vivo. Genome-wide occupancy and transcriptomic analyses identified Dkk3 (encoding the Dickkopf-3 protein) as a direct transcriptional target of FoxO4. Consistent with the FoxO4-DKK3 relationship, recombinant DKK3 protein restored normal levels of IFN-γ production in FoxO4-deficient Th1 cells through the downregulation of lymphoid enhancer–binding factor 1 (Lef1) expression. Together, our data suggest a potential FoxO4/DKK3 axis in Th1 cell differentiation, providing what we believe to be an important insight and supplement for FoxO family proteins in T lymphocyte biology and revealing a promising target for the treatment of immune-related diseases.
Authors
Xiang Chen, Jia Hu, Yunfei Wang, Younghee Lee, Xiaohong Zhao, Huiping Lu, Gengzhen Zhu, Hui Wang, Yu Jiang, Fan Liu, Yongzhen Chen, Byung-Seok Kim, Qinghua Zhou, Xindong Liu, Xiaohu Wang, Seon Hee Chang, Chen Dong
Abstract
Myelodysplastic syndromes (MDS) are age-related myeloid neoplasms with increased risk of progression to acute myeloid leukemia (AML). The mechanisms of transformation of MDS to AML are poorly understood, especially in relation to the aging microenvironment. We previously established an mDia1/miR-146a double knockout (DKO) mouse model phenocopying MDS. These mice develop age-related pancytopenia with oversecretion of proinflammatory cytokines. Here, we found that most of the DKO mice underwent leukemic transformation at 12–14 months of age. These mice showed myeloblast replacement of fibrotic bone marrow and widespread leukemic infiltration. Strikingly, depletion of IL-6 in these mice largely rescued the leukemic transformation and markedly extended survival. Single-cell RNA sequencing analyses revealed that DKO leukemic mice had increased monocytic blasts that were reduced with IL-6 knockout. We further revealed that the levels of surface and soluble IL-6 receptor (IL-6R) in the bone marrow were significantly increased in high-risk MDS patients. Similarly, IL-6R was also highly expressed in older DKO mice. Blocking of IL-6 signaling significantly ameliorated AML progression in the DKO model and clonogenicity of CD34-positive cells from MDS patients. Our study establishes a mouse model of progression of age-related MDS to AML and indicates the clinical significance of targeting IL-6 signaling in treating high-risk MDS.
Authors
Yang Mei, Kehan Ren, Yijie Liu, Annabel Ma, Zongjun Xia, Xu Han, Ermin Li, Hamza Tariq, Haiyan Bao, Xinshu Xie, Cheng Zou, Dingxiao Zhang, Zhaofeng Li, Lili Dong, Amit Verma, Xinyan Lu, Yasmin Abaza, Jessica K. Altman, Madina Sukhanova, Jing Yang, Peng Ji
Abstract
The in vivo persistence of adoptively transferred T cells is predictive of antitumor response. Identifying functional properties of infused T cells that lead to in vivo persistence and tumor eradication has remained elusive. We profiled CD19-specific chimeric antigen receptor (CAR) T cells as the infusion products used to treat large B cell lymphomas using high-throughput single-cell technologies based on time-lapse imaging microscopy in nanowell grids (TIMING), which integrates killing, cytokine secretion, and transcriptional profiling. Our results show that the directional migration of CD19-specific CAR T cells is correlated with multifunctionality. We showed that CD2 on T cells is associated with directional migration and that the interaction between CD2 on T cells and CD58 on lymphoma cells accelerates killing and serial killing. Consistent with this, we observed that elevated CD58 expression on pretreatment tumor samples in patients with relapsed or refractory large B cell lymphomas treated with CD19-specific CAR T cell therapy was associated with complete clinical response and survival. These results highlight the importance of studying dynamic T cell–tumor cell interactions in identifying optimal antitumor responses.
Authors
Gabrielle Romain, Paolo Strati, Ali Rezvan, Mohsen Fathi, Irfan N. Bandey, Jay R T. Adolacion, Darren Heeke, Ivan Liadi, Mario L. Marques-Piubelli, Luisa M. Solis, Ankit Mahendra, Francisco Vega, Laurence J.N. Cooper, Harjeet Singh, Mike Mattie, Adrian Bot, Sattva S. Neelapu, Navin Varadarajan
Abstract
Immune checkpoint blockade (ICB) has demonstrated clinical success in “inflamed” tumors with substantial T cell infiltrates, but tumors with an immune-desert tumor microenvironment (TME) fail to benefit. The tumor cell–intrinsic molecular mechanisms of the immune-desert phenotype remain poorly understood. Here, we demonstrated that inactivation of the polycomb-repressive complex 2 (PRC2) core components embryonic ectoderm development (EED) or suppressor of zeste 12 homolog (SUZ12), a prevalent genetic event in malignant peripheral nerve sheath tumors (MPNSTs) and sporadically in other cancers, drove a context-dependent immune-desert TME. PRC2 inactivation reprogramed the chromatin landscape that led to a cell-autonomous shift from primed baseline signaling-dependent cellular responses (e.g., IFN-γ signaling) to PRC2-regulated developmental and cellular differentiation transcriptional programs. Further, PRC2 inactivation led to diminished tumor immune infiltrates through reduced chemokine production and impaired antigen presentation and T cell priming, resulting in primary resistance to ICB. Intratumoral delivery of inactivated modified vaccinia virus Ankara (MVA) enhanced tumor immune infiltrates and sensitized PRC2-loss tumors to ICB. Our results identify molecular mechanisms of PRC2 inactivation–mediated, context-dependent epigenetic reprogramming that underline the immune-desert phenotype in cancer. Our studies also point to intratumoral delivery of immunogenic viruses as an initial therapeutic strategy to modulate the immune-desert TME and capitalize on the clinical benefit of ICB.
Authors
Juan Yan, Yuedan Chen, Amish J. Patel, Sarah Warda, Cindy J. Lee, Briana G. Nixon, Elissa W.P. Wong, Miguel A. Miranda-Román, Ning Yang, Yi Wang, Mohini R. Pachai, Jessica Sher, Emily Giff, Fanying Tang, Ekta Khurana, Sam Singer, Yang Liu, Phillip M. Galbo Jr., Jesper L.V. Maag, Richard P. Koche, Deyou Zheng, Cristina R. Antonescu, Liang Deng, Ming O. Li, Yu Chen, Ping Chi
Abstract
Solid organ transplantation is the preferred treatment for end-stage organ failure. Although transplant recipients take life-long immunosuppressive drugs, a substantial percentage of them still reject their allografts. Strikingly, barrier organs colonized with microbiota have significantly shorter half-lives than non-barrier transplanted organs, even in immunosuppressed hosts. We previously demonstrated that skin allografts monocolonized with the common human commensal Staphylococcus epidermidis (S.epi) are rejected faster than germ-free (GF) allografts in mice because the presence of S.epi augments the effector alloimmune response locally in the graft. Here, we tested whether host immune responses against graft-resident commensal microbes, including S.epi, can damage colonized grafts independently from the alloresponse. Naive hosts mounted an anticommensal T cell response to colonized, but not GF, syngeneic skin grafts. Whereas naive antigraft commensal T cells modestly damaged colonized syngeneic skin grafts, hosts with prior anticommensal T cell memory mounted a post-transplant immune response against graft-resident commensals that significantly damaged colonized, syngeneic skin grafts. Importantly, allograft recipients harboring this host-versus-commensal immune response resisted immunosuppression. The dual effects of host-versus-commensal and host-versus-allograft responses may partially explain why colonized organs have poorer outcomes than sterile organs in the clinic.
Authors
Isabella Pirozzolo, Martin Sepulveda, Luqiu Chen, Ying Wang, Yuk Man Lei, Zhipeng Li, Rena Li, Husain Sattar, Betty Theriault, Yasmine Belkaid, Anita S. Chong, Maria-Luisa Alegre
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ISSN: 0021-9738 (print), 1558-8238 (online)