Increased joint loading induces subchondral bone loss of temporomandibular joint via the RANTES-CCRs-Akt2 axis

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Abstract

Early-stage temporomandibular joint osteoarthritis (TMJOA) is characterized by excessive subchondral bone loss. Emerging evidence suggests that TMJ disc displacement is involved, but the pathogenic mechanism remains unclear. Here, we established a rat model of TMJOA that simulated disc displacement and a capacitance-based force sensing system to directly measure articular surface pressure in vivo. Micro-CT, histological staining, immunofluorescence staining, immunohistochemistry staining, and Western blot were used to assess pathological changes and underlying mechanism of TMJOA in the rat model in vivo as well as in RAW264.7 cells in vitro. We found that disc displacement led to significantly higher pressure on articular surface, which caused subchondral bone loss rapidly via activation of RANTES-CCRs-Akt2 axis. Inhibition of RANTES or Akt2 attenuated subchondral bone loss and resulted in improved subchondral bone microstructure. Cytological studies substantiated that RANTES regulated osteoclast formation by binding to its receptor CCRs and activating Akt2 pathway. The clinical evidence further supported that RANTES was a potential biomarker for predicting subchondral bone loss in early-stage TMJOA. Taken together, this study demonstrates important functions of RANTES-CCRs-Akt2 axis in the regulation of subchondral bone remodeling and provides further knowledge of how disc displacement causes TMJOA.

Authors

Shi-Yang Feng, Jie Lei, Yu-Xiang Li, Wen-Ge Shi, Ran-Ran Wang, Adrian Ujin Yap, Yi-Xiang Wang, Kai-Yuan Fu

Distinct pre-treatment innate immune landscape and post-treatment T cell responses underlie immunotherapy-induced colitis

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Abstract

Immune-related adverse events are a major hurdle to the success of immunotherapy. The immunological mechanisms underlying their development and relation to anti-tumour responses are poorly understood. By examining both systemic and tissue-specific immune changes induced by combination anti-CTLA-4 and anti-PD-1 immunotherapy, we found distinct repertoire changes in patients who developed moderate-severe colitis irrespective of their anti-tumour response to therapy. The proportion of circulating monocytes were significantly increased at baseline in patients who subsequently developed colitis compared to patients who did not develop colitis and biopsies from patients with colitis showed monocytic infiltration of both endoscopically and histopathologically normal and inflamed regions of colon. The magnitude of systemic expansion of T cells following commencement of immunotherapy was also greater in patients who developed colitis. Importantly, we show expansion of specific T cell subsets within inflamed regions of the colon, including tissue-resident memory CD8+ T cells and Th1 CD4+ T cells in patients who developed colitis. Our data also suggest that CD8+ T cell expansion was locally induced, while Th1 cell expansion was systemic. Together our data show exaggerated innate and T cell responses to combination immunotherapy synergise to propel colitis in susceptible patients.

Authors

Kazi J. Nahar, Felix Marsh-Wakefield, Robert V. Rawson, Tuba N. Gide, Angela L. Ferguson, Ruth O. Allen, Camelia Quek, Ines Pires da Silva, Stephen Tattersall, Christopher J. Kiely, Neomal Sandanayake, Matteo S. Carlino, Geoff McCaughan, James S. Wilmott, Richard A. Scolyer, Georgina V. Long, Alexander M. Menzies, Umaimainthan Palendira

Antisense oligonucleotide therapy for KCNT1 encephalopathy

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Abstract

Developmental and epileptic encephalopathies (DEE) are characterized by pharmacoresistant seizures with concomitant intellectual disability. Epilepsy of infancy with migrating focal seizures (EIMFS) is one of the most severe of these syndromes. De novo variants in ion channels, including gain-of-function variants in KCNT1, have been found to play a major role in the etiology of EIMFS. Here, we test a potential precision therapeutic approach in KCNT1-associated DEE using a gene silencing antisense oligonucleotide (ASO) approach. We generated a mouse model carrying the KCNT1 p.P924L pathogenic variant; only the homozygous animals presented with the frequent, debilitating seizures and developmental compromise that are seen in patients. After a single intracerebroventricular bolus injection of a Kcnt1 gapmer ASO in symptomatic mice at postnatal day 40, seizure frequency was significantly reduced, behavioral abnormalities improved, and overall survival was extended compared to mice treated with a control ASO (non-hybridizing sequence). ASO administration at neonatal age was also well-tolerated and effective in controlling seizures and extending the lifespan of treated animals. The data presented here provide proof of concept for ASO-based gene silencing as a promising therapeutic approach in KCNT1-associated epilepsies.

Authors

Lisseth E. Burbano, Melody Li, Nikola Jancovski, Paymaan Jafar-nejad, Kay Richards, Alicia Sedo, Armand Soriano, Ben Rollo, Linghan Jia, Elena V. Gazina, Sandra Piltz, Fatwa Adikusuma, Paul Q. Thomas, Helen Kopsidas, Frank Rigo, Christopher A. Reid, Snezana Maljevic, Steven Petrou

A heterozygous LAMA5 variant may contribute to slowly progressive, vinculin-enhanced familial FSGS and pulmonary defects

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Abstract

The LAMA5 gene encodes laminin α5, an indispensable component of glomerular basement membrane and other types of basement membrane. A homozygous pathological variant in LAMA5 is known to cause systemic developmental syndrome, including glomerulopathy. However, the roles of heterozygous LAMA5 gene variants in human renal and systemic disease have remained unclear. We performed whole-exome sequence analyses of a family with slowly progressive nephropathy associated with hereditary focal segmental glomerulosclerosis; we identified a probable pathogenic novel variant of LAMA5, NP_005551.3:p.Val3687Met. In vitro analyses revealed cell type-dependent changes in secretion of variant laminin α5 LG4-5 domain. Heterozygous and homozygous knock-in mice with a corresponding variant of human LAMA5, p.Val3687Met, developed focal segmental glomerulosclerosis-like pathology with reduced laminin α5 and increased glomerular vinculin levels; this suggested that impaired cell adhesion may underlie this glomerulopathy. We also identified pulmonary defects such as bronchial deformity and alveolar dilation. Re-examinations of the family revealed phenotypes compatible with reduced laminin α5 and increased vinculin levels in affected tissues. Thus, the heterozygous p.Val3687Met variant may cause a new syndromic nephropathy with focal segmental glomerulosclerosis through possibly defective secretion of laminin α5. Enhanced vinculin may be a useful disease marker.

Authors

Jun-Ya Kaimori, Yamato Kikkawa, Daisuke Motooka, Tomoko Namba-Hamano, Ayako Takuwa, Atsuko Imai-Okazaki, Kaori Kobayashi, Arisa Tanigawa, Yuko Kotani, Yoshihiro Uno, Kazuto Yoshimi, Koki Hattori, Yuta Asahina, Sachio Kajimoto, Yohei Doi, Tatsufumi Oka, Yusuke Sakaguchi, Tomoji Mashimo, Kiyotoshi Sekiguchi, Akihiro Nakaya, Motoyoshi Nomizu, Yoshitaka Isaka

Cell-free and alkylated hemoproteins improve survival in mouse models of carbon monoxide poisoning

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Abstract

Intravenous administration of a high affinity carbon monoxide (CO)-binding molecule, recombinant neuroglobin, can improve survival in CO poisoning mouse models. The current study aims to understand how biochemical variables of the scavenger determine the CO removal from the RBCs by evaluating three readily available hemoproteins, 2,3-diphosphoglycerate stripped human hemoglobin (StHb), N-ethylmaleimide modified hemoglobin (NEMHb), and equine myoglobin (Mb). These molecules efficiently sequester CO from hemoglobin in erythrocytes in vitro. A kinetic model was developed to predict the CO binding efficacy for hemoproteins, based on their measured in vitro oxygen and CO binding affinities, suggesting that the therapeutic efficacy of hemoproteins for CO poisoning relates to a high M value, which is the binding affinity for CO relative to oxygen (KA,CO/KA,O2). In a lethal CO poisoning mouse model, StHb, NEMHb, and Mb improved survival by 100%, 100%, and 60%, respectively, compared with saline controls, and were well tolerated in 48-hour toxicology assessments. In conclusion, both StHb and NEMHb have high CO binding affinities and M values and scavenge CO efficiently in vitro and in vivo, highlighting their therapeutic potential for point-of-care antidotal therapy of CO poisoning.

Authors

Qinzi Xu, Jason J. Rose, Xiukai Chen, Ling Wang, Anthony W. DeMartino, Matthew R. Dent, Sagarika Tiwari, Kaitlin Bocian, Xueyin N. Huang, Qin Tong, Charles F. McTiernan, Lanping Guo, Elmira Alipour, Trevor C. Jones, Kamil Burak Ucer, Daniel B. Kim-Shapiro, Jesus Tejero, Mark T. Gladwin

Interleukin-37 protects against acinar cell pyroptosis in acute pancreatitis

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Abstract

Acute pancreatitis (AP) is a local and/or systemic inflammatory disease that starts with acinar cell injury and necrosis, which has no effective medical treatment and thus remains a life-threatening condition. Interleukin-37 (IL-37), a natural immunomodulator, has demonstrated an anti-inflammatory effect; however, the role of IL-37 in AP remains unknown. The serum IL-37 levels of 39 healthy controls and 94 AP patients were measured. Cholecystokinin was applied to induce pancreatic acinar cell injury in vitro. Classical experimental AP models, such as caerulein, L-arginine, and Taurocholic acid sodium salt were included in the in vivo study. A transgenic mouse model with the IL-37 gene and administration of recombinant IL-37 were used to further investigate the function of IL-37 in AP. Pancreas-specific GSDMD knockout mice were used to explore the protective mechanism of IL-37. Our results showed that serum IL-37 levels of human were negatively correlated with the severity of AP. Furthermore, transgenic IL-37 mice and supplementation with recombinant IL-37 could both protect against AP. Mechanistically, IL-37 was able to suppress pyroptosis of injured acinar cells, and specific depletion of GSDMD in the pancreas counteracted the protective effect of IL-37. Our study demonstrates that IL-37 protects against acinar cell pyroptosis in AP.

Authors

Nan Ma, Chenchen Yuan, Juanjuan Shi, Qingtian Zhu, Yang Liu, Xiaojie Ma, Baiqiang Li, Weijuan Gong, Jing Xue, Guotao Lu, Weiqin Li, Jieshou Li

Immunogenetics associated with severe coccidioidomycosis

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Abstract

Disseminated coccidioidomycosis (DCM) is caused by Coccidioides, pathogenic fungi endemic to the Southwestern United States and Mexico. Illness occurs in approximately 30% of those infected, <1% of whom develop disseminated disease. To address why some individuals allow dissemination, we enrolled DCM patients and performed whole-exome sequencing. In an exploratory set of 67 DCM patients, two had haploinsufficient STAT3 mutations, while defects in β-glucan sensing and response were seen in 34/67 (50.7%) cases. Damaging CLEC7A (n=14) and PLCG2 (n=11) variants were associated with impaired production of β-glucan-stimulated TNF-α from peripheral blood mononuclear cells compared to healthy controls (P<0.005). Using ancestry-matched controls, damaging CLEC7A and PLCG2 variants were over-represented in DCM (P=0.0206, P=0.015, respectively) including CLEC7A Y238* (P=0.0105) and PLCG2 R268W (P=0.0025). A validation cohort of 111 DCM patients confirmed PLCG2 R268W (P=0.0276), CLEC7A I223S (P=0.044), and CLEC7A Y238* (P=0.0656). Stimulation with a DECTIN-1 agonist induced DUOX1/DUOXA1-derived H2O2 in transfected cells. Heterozygous DUOX1 or DUOXA1 variants which impaired H2O2 production were overrepresented in discovery and validation cohorts. Patients with DCM have impaired β-glucan sensing or response affecting TNF-α and H2O2 production. Impaired Coccidioides recognition and decreased cellular response are associated with disseminated coccidioidomycosis.

Authors

Amy P. Hsu, Agnieszka Korzeniowska, Cynthia C. Aguilar, Jingwen Gu, Eric Karlins, Andrew J. Oler, Gang Chen, Glennys V. Reynoso, Joie Davis, Alexandria Chaput, Tao Peng, Ling Sun, Justin B. Lack, Derek J. Bays, Ethan R. Stewart, Sarah E. Waldman, Daniel A. Powell, Fariba M. Donovan, Jigar V. Desai, Nima Pouladi, Debra A. Long Priel, Daisuke Yamanaka, Sergio D. Rosenzweig, Julie E. Niemela, Jennifer Stoddard, Alexandra F. Freeman, Christa S. Zerbe, Douglas B. Kuhns, Yves A. Lussier, Kenneth N. Olivier, Richard C. Boucher, Heather D. Hickman, Jeffrey Frelinger, Joshua Fierer, Lisa F. Shubitz, Thomas L. Leto, George R. Thompson III, John N. Galgiani, Michail S. Lionakis, Steven M. Holland

Liposomal UHRF1 siRNA shows lung fibrosis treatment potential by regulating fibroblast activation

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Abstract

Pulmonary fibrosis is a chronic and progressive interstitial lung disease associated with the decay of pulmonary function leading to a fatal outcome. As an essential epigenetic regulator of DNA methylation, the involvement of Ubiquitin-like containing PHD and RING finger domains 1 (UHRF1) in fibroblast activation remains largely undefined in pulmonary fibrosis. In the present study, we found that growth factor–β1(TGF-β1)-mediated upregulation of UHRF1 repressed Beclin1 via its promoter methylation induction which finally results in fibroblast activation and lung fibrosis both in vitro and in vivo. Moreover, knockdown of UHRF1 significantly arrested fibroblast proliferation and reactivated Beclin 1 in lung fibroblasts. Henceforth, intravenous administration of UHRF1 siRNA-loaded liposomes significantly protected mice against experimental pulmonary fibrosis. Accordingly, our data suggested that UHRF1 might be a novel potential therapeutic target in the pathogenesis of pulmonary fibrosis.

Authors

Demin Cheng, Yue Wang, Ziwei Li, Haojie Xiong, Wenqing Sun, Sichuan Xi, Siyun Zhou, Yi Liu, Chunhui Ni

DIO3 protects from thyrotoxicosis-derived cranio-encephalic and cardiac congenital abnormalities

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Abstract

Maternal hyperthyroidism is associated with an increased incidence of congenital abnormalities at birth, but it is not clear which of those defects arise from a transient developmental excess of thyroid hormone, and which depend on pregnancy stage, antithyroid drug choice, or unwanted subsequent fetal hypothyroidism. To address this issue we studied a mouse model of comprehensive developmental thyrotoxicosis secondary to a lack of type 3 deiodinase (DIO3). Dio3-/- mice exhibit reduced neonatal viability on most genetic backgrounds and perinatal lethality on a C57BL/6 background. Dio3-/- mice exhibit severe growth retardation during the neonatal period and cartilage loss. Mice surviving after birth manifest brain and cranial dysmorphisms, severe hydrocephalus, choanal atresia, and cleft palate. These abnormalities are noticeable in C57BL/6J Dio3-/- mice at fetal stages, in addition to a thyrotoxic heart with septal defects and thin ventricular walls. Our findings stress the protecting role of DIO3 during development and support the hypothesis that human congenital abnormalities associated with hyperthyroidism during pregnancy are caused by transient thyrotoxicosis before clinical intervention. Our results also suggest thyroid hormone involvement in the etiology of idiopathic pathologies including cleft palate, choanal atresia, Chiari malformations, Kaschin-Beck disease, and Temple and other cranio-encephalic and heart syndromes.

Authors

M. Elena Martinez, Ilka Pinz, Marilena Preda, Christine R. Norton, Thomas Gridley, Arturo Hernandez

A human STAT3 gain-of-function variant confers T cell dysregulation without predominant Treg dysfunction in mice

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Abstract

Primary immune regulatory disorders (PIRD) are a group of disorders characterized by immune dysregulation, presenting with a wide range of clinical disease including autoimmunity, autoinflammation, or lymphoproliferation. Autosomal dominant germline gain-of-function (GOF) variants in STAT3 result in a PIRD with a broad clinical spectrum. Studies in patients have documented a decreased frequency of FOXP3+ regulatory T (Treg) cells and an increased frequency of Th17 cells in some patients with active disease. However, the mechanisms of disease pathogenesis in STAT3 GOF syndrome remain largely unknown, and treatment is challenging. We developed a knock-in mouse model harboring a de novo pathogenic human STAT3 variant (p.G421R) and found these mice developed T cell dysregulation, lymphoproliferation and CD4+ Th1 cell skewing. Surprisingly, Treg cell numbers, phenotype, and function remained largely intact, however mice had a selective deficiency in the generation of iTreg cells. In parallel, we performed single-cell RNA-sequencing on T cells from STAT3 GOF patients. We demonstrate only minor changes in the Treg cell transcriptional signature and an expanded, effector CD8+ T cell population. Together, these findings suggest Treg cells are not the primary driver of disease and highlight the importance of preclinical models in the study of disease mechanisms in rare PIRD.

Authors

Erica G. Schmitt, Kelsey A. Toth, Samuel I. Risma, Ana Kolicheski, Nermina Saucier, Rafael J. Feliciano Berríos, Zev J. Greenberg, Jennifer W. Leiding, Jack J. Bleesing, Akaluck Thatayatikom, Laura G. Schuettpelz, John R. Edwards, Tiphanie P. Vogel, Megan A. Cooper