The efficacy of abatacept in patients with early diffuse systemic sclerosis (dcSSc) was analyzed to test the hypothesis that patients in the inflammatory intrinsic gene expression subset would show the most significant clinical improvement. 84 participants with dcSSc were randomized to receive abatacept or placebo for 12 months. RNA-seq was performed on 233 skin paired biopsies at baseline, 3- and 6-months. Improvement was defined as a 5 point or >20% change in modified Rodnan skin score (mRSS) between baseline and 12 months. Samples were assigned to intrinsic gene expression subset (inflammatory, fibroproliferative, or normal-like). In the abatacept arm, change in mRSS was most pronounced for the inflammatory (p<0.001) and normal-like (p=0.03) subsets relative to placebo. Participants on placebo remained in their molecular subset while inflammatory participants treated with abatacept moved toward normal-like. The CD28 costimulation pathway decreased in patients that improved on abatacept (FDR=5.88x10-4) and was specific to the inflammatory subset (FDR=0%). Patients in the inflammatory subset had elevation of the CD28 costimulation pathway at baseline relative to fibroproliferative (p = 0.0026) and normal-like (p=0.0001) participants. There was a correlation between improved ΔmRSS and baseline expression of the CD28 costimulation pathway (R=-0.62, p=0.02). This study provides an example of precision medicine in SSc clinical trials.
Bhaven K. Mehta, Monica E. Espinoza, Jennifer M. Franks, Yiwei Yuan, Yue Wang, Tammara Wood, Johann Gudjonsson, Cathie Spino, David A. Fox, Dinesh Khanna, Michael L. Whitfield
Glucocorticoids remain a cornerstone of therapeutic regimes for autoimmune and chronic inflammatory diseases, for example, in different forms of crescentic glomerulonephritis because of their rapid anti-inflammatory effects, low cost, and wide availability. Despite their routine use for decades, the underlying cellular mechanisms by which steroids exert their therapeutic effects need to be fully elucidated. Here, we demonstrate that high-dose steroid treatment rapidly reduced the number of proinflammatory CXCR3+ CD4+ T cells in the kidney by combining high-dimensional single-cell and morphological analyses of kidney biopsies from patients with antineutrophil cytoplasmic antibody (ANCA)-associated crescentic glomerulonephritis. Using an experimental model of crescentic glomerulonephritis, we show that the steroid-induced decrease in renal CD4+ T cells is a consequence of reduced T-cell recruitment, which is associated with an ameliorated disease course. Mechanistic in vivo and in vitro studies revealed that steroids act directly on renal tissue cells, such as tubular epithelial cells, but not on T cells, which resulted in an abolished renal expression of CXCL9 and CXCL10, as well as in the prevention of CXCR3+ CD4+ T-cell recruitment to the inflamed kidneys. Thus, we identified the CXCL9/10-CXCR3 axis as a previously unrecognized cellular and molecular target of glucocorticoids providing protection from immune-mediated pathology.
Jan-Hendrik Riedel, Lennart Robben, Hans-Joachim Paust, Yu Zhao, Nariaki Asada, Ning Song, Anett Peters, Anna Kaffke, Alina C. Borchers, Gisa Tiegs, Larissa Seifert, Nicola M. Tomas, Elion Hoxha, Ulrich O. Wenzel, Tobias B. Huber, Thorsten Wiech, Jan-Eric Turner, Christian F. Krebs, Ulf Panzer
Antisense oligonucleotides (ASOs) have emerged as one of the most innovative new genetic drug modalities. However, their high molecular weight limits their bioavailability for otherwise treatable neurological disorders. We investigated conjugation of ASOs to an antibody against the murine transferrin receptor (TfR), 8D3130, and evaluated it via systemic administration in mouse models of the neurodegenerative disease, spinal muscular atrophy (SMA). SMA, like several other neurological and neuromuscular diseases, is treatable with single-stranded ASOs that modulate splicing of the survival motor neuron 2 (SMN2) gene. Administration of 8D3130-ASO conjugate resulted in elevated levels of bioavailability to the brain. Additionally, 8D3130-ASO yielded therapeutic levels of SMN2 splicing in the central nervous system of adult hSMN2 transgenic mice which resulted in extended survival of a severely affected SMA mouse model. Systemic delivery of nucleic acid therapies with brain targeting antibodies offers powerful translational potential for future treatments of neuromuscular and neurodegenerative diseases.
Suzan M. Hammond, Frank Abendroth, Larissa Goli, Jessica Stoodley, Matthew Burrell, George Thom, Ian Gurrell, Nina Ahlskog, Michael J. Gait, Matthew J.A. Wood, Carl I. Webster
Clinical outcomes after lung transplantation, a life-saving therapy for patients with end-stage lung diseases, are limited by primary graft dysfunction (PGD). PGD is an early form of acute lung injury with no specific pharmacologic therapies. Here, we present a large multicenter study of plasma and bronchoalveolar lavage (BAL) samples collected on the first post-transplant day, a critical time for investigations of immune pathways related to PGD. We demonstrated that ligands for NKG2D receptors were increased in the BAL from participants who developed severe PGD and were associated with increased time to extubation, prolonged intensive care unit length of stay, and poor peak lung function. Neutrophil extracellular traps (NETs) were increased in PGD and correlated with BAL TNF-α and IFN-γ cytokines. Mechanistically, we found that airway epithelial cell NKG2D ligands were increased following hypoxic challenge. Natural killer (NK) cell killing of hypoxic airway epithelial cells was abrogated with NKG2D receptor blockade, and TNF-α and IFN-γ provoked neutrophils to release NETs in culture. Together, these data support an aberrant NK cell-neutrophil axis in human PGD pathogenesis. Early measurement of stress ligands and blockade of the NKG2D receptor hold promise for risk stratification and management of PGD.
Daniel R. Calabrese, Tasha Tsao, Mélia Magnen, Colin Valet, Ying Gao, Beñat Mallavia, Jennifer J. Tian, Emily A. Aminian, Kristin M. Wang, Avishai Shemesh, Elman B. Punzalan, Aartik Sarma, Carolyn S. Calfee, Stephanie A. Christenson, Charles R. Langelier, Steven R. Hays, Jeff A. Golden, Lorriana E. Leard, Mary E. Kleinhenz, Nicholas A. Kolaitis, Rupal J. Shah, Aida Venado, Lewis L. Lanier, John R. Greenland, David M. Sayah, Abbas Ardehali, Jasleen Kukreja, S. Sam Weigt, John A. Belperio, Jonathan P Singer, Mark R. Looney
Mutations in the BRCA1 tumor suppressor gene, such as 5382insC (BRCA15382insC), give carriers an increased risk for breast, ovarian, prostate and pancreatic cancers. We have previously reported that, in mice, Brca1 deficiency in the hematopoietic system leads to pancytopenia and, as a result, early lethality. Here we explore the cellular consequences of Brca1 null and BRCA1 5382insC alleles in combination with Tp53 deficiency in the murine hematopoietic system. We find that Brca1 and Tp53 co-deficiency leads to a highly penetrant erythroproliferative disorder that is characterized by hepatosplenomegaly and expanded megakaryocyte erythroid progenitor (MEP) and immature erythroid blast populations. The expanded erythroid progenitor populations in both bone marrow and spleen have the capacity to transmit the disease into secondary mouse recipients, suggesting Brca1 and Tp53 co-deficiency provides a new murine model of hematopoietic neoplasia. This Brca1/Tp53 model replicates Poly (ADP-ribose) polymerase (PARP) inhibitor olaparib sensitivity seen in existing Brca1/Tp53 breast cancer models and has the benefits of monitoring disease progression and drug responses via peripheral blood analyses without sacrificing experimental animals. In addition, this erythroid neoplasia develops much faster than murine breast cancer, allowing for increased efficiency of future preclinical studies.
Gerardo Lopez-Perez, Ranjula Wijayatunge, Kelly B. McCrum, Sam R. Holmstrom, Victoria E. Mgbemena, Theodora S. Ross
Muscle weakness and wasting are defining features of cancer-induced cachexia. Mitochondrial stress occurs before atrophy in certain muscles, but the possibility of heterogeneous responses between muscles and across time remains unclear. Using mice inoculated with Colon-26 (C26) cancer, we demonstrate that specific force production was reduced in quadriceps and diaphragm at 2 weeks in the absence of atrophy. At this time, pyruvate-supported mitochondrial respiration was lower in quadriceps while mitochondrial H2O2 emission was elevated in diaphragm. By 4 weeks, atrophy occurred in both muscles, but specific force production increased to control levels in quadriceps such that reductions in absolute force were due entirely to atrophy. Specific force production remained reduced in diaphragm. Mitochondrial respiration increased and H2O2 emission was unchanged in both muscles vs control while mitochondrial creatine sensitivity was reduced in quadriceps. These findings indicate muscle weakness precedes atrophy and is linked to heterogeneous mitochondrial alterations that could involve adaptive responses to metabolic stress. Eventual muscle-specific restorations in force and bioenergetics highlight how the effects of cancer on one muscle do not predict the response in another muscle. Exploring heterogeneous responses of muscle to cancer may reveal new mechanisms underlying distinct sensitivities, or resistance, to cancer cachexia.
Luca J. Delfinis, Catherine A. Bellissimo, Shivam Gandhi, Sara N. DiBenedetto, Madison C. Garibotti, Arshdeep K. Thuhan, Stavroula Tsitkanou, Megan E. Rosa-Caldwell, Fasih A. Rahman, Arthur J. Cheng, Michael P. Wiggs, Uwe Schlattner, Joe Quadrilatero, Nicholas P. Greene, Christopher G.R. Perry
Leukocyte Adhesion Deficiency Type-1 (LAD-1) is a rare disease resulting from mutations in the gene encoding for the common β-chain of the ß2 integrin family (CD18). The most prominent clinical symptoms are profound leukocytosis and high susceptibility to infections. At the same time, LAD-1 patients are prone to develop autoimmune diseases, but the molecular and cellular mechanisms that result in coexisting immunodeficiency and autoimmunity are still unresolved. CD4+FOXP3+ regulatory T cells (Treg) are known for their essential role in preventing autoimmunity. To understand the role of Treg in LAD-1 development and manifestation of autoimmunity we generated mice specifically lacking CD18 on Treg (CD18Foxp3), resulting in defective LFA-1 expression. Here we demonstrate a crucial role of LFA-1 on Treg to maintain immune homeostasis by modifying T cell – dendritic cell (DC) interactions and CD4+ T cell activation. Treg-specific CD18 deletion did not impair Treg migration into extra-lymphatic organs but resulted in shorter interactions of Treg with DC. In vivo, CD18Foxp3 mice developed spontaneous hyperplasia in lymphatic organs, and diffuse inflammation of the skin and in multiple internal organs. Thus, LFA-1 on Treg is required for the maintenance of immune homeostasis.
Tanja Klaus, Alicia S. Wilson, Elisabeth Vicari, Eva Hadaschik, Matthias Klein, Sara Salome Helbich, Nadine Kamenjarin, Katrin Hodapp, Jenny Schunke, Maximilian Haist, Florian Butsch, Hans C. Probst, Alexander H. Enk, Karsten Mahnke, Ari Waisman, Monika Bednarczyk, Matthias Bros, Tobias Bopp, Stephan Grabbe
Vasopressin has traditionally been thought to be produced by the neurohypophyseal system and then released into the circulation where it regulates water homeostasis. The syndrome of inappropriate secretion of anti-diuretic hormone (vasopressin) raised the question if vasopressin could be produced outside of the brain and whether the kidney could be a source of vasopressin. We found that mouse and human kidneys expressed vasopressin mRNA. Using an antibody that detects the pre-pro-vasopressin, we found that immunoreactive pre-pro-vasopressin protein is found in mouse and human kidneys. Moreover, we found that murine collecting duct cells make biologically active vasopressin which increases in response to NaCl mediated hypertonicity, and that water restriction increases the abundance of kidney-derived vasopressin mRNA and protein expression in mouse kidneys. Thus, we provide evidence of biologically active production of kidney-derived vasopressin in kidney tubular epithelial cells.
Juan P. Arroyo, Andrew S. Terker, Yvonne Zuchowski, Jason A. Watts, Fabian Bock, Cameron Meyer, Wentian Luo, Meghan E. Kapp, Edward R. Gould, Adam X Miranda, Joshua Carty, Ming Jiang, Roberto M. Vanacore, Elizabeth Hammock, Matthew H. Wilson, Roy Zent, Mingzhi Zhang, Gautam Bhave, Raymond C. Harris
Acute lung injury (ALI) is a severe form of lung inflammation causing acute respiratory distress syndrome in patients. ALI pathogenesis is closely linked to uncontrolled alveolar inflammation. We hypothesize that specific enzymes of the glycolytic pathway could function as key regulators of alveolar inflammation. Therefore, we screened isolated alveolar epithelia from mice exposed to ALI induced by injurious ventilation to assess their metabolic responses. These studies pointed us towards a selective role for isoform 3 of the 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB3). Pharmacologic inhibition or genetic deletion of Pfkfb3 in alveolar epithelia (Pfkfb3loxp/loxp SPC-ER-Cre+ mice) was associated with profound increases in ALI during injurious mechanical ventilation or acid installation. Studies in genetic models linked Pfkfb3 expression and function to hypoxia-inducible factor Hif1a. Intra-tracheal pyruvate instillation not only reconstituted Pfkfb3loxp/loxp or Hif1aloxp/loxp SPC ER Cre+ mice, but pyruvate was also effective in ALI treatment of wild-type mice. Finally, proof-of-principle studies in human lung biopsies confirmed increased PFKFB3 staining in injured lungs and co-localized PFKFB3 to alveolar epithelia. These studies reveal a specific role for PFKFB3 in counter-balancing alveolar inflammation and lay the groundwork for novel metabolic therapeutic approaches during ALI.
Christine U. Vohwinkel, Nana Burns, Ethan Coit, Xiaoyi Yuan, Eszter K. Vladar, Christina Sul, Eric P. Schmidt, Peter Carmeliet, Kurt Stenmark, Eva S. Nozik, Rubin M. Tuder, Holger K. Eltzschig
There is limited data on the link between cardiac autonomic neuropathy (CAN) and severe hypoglycemia, in type 2 diabetes. We evaluated the associations of CAN with severe hypoglycemia among 7,421 adults with type 2 diabetes from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study. CAN was defined using electrocardiogram-derived measures. Cox and Andersen-Gill regression models were used to generate hazard ratios (HRs) for first and recurrent severe hypoglycemic episodes, respectively. Over 4.7 years, there were 558 first and 811 recurrent hypoglycemic events. Participants with CAN had increased risks of first (HR 1.23, 95%CI 1.01-1.50) or recurrent (HR: 1.46, 95%CI 1.16-1.84) episodes of severe hypoglycemia. The intensity of glycemic management modified the CAN association with hypoglycemia (P for interaction <0.05). In the standard glycemic management group, compared to participants without CAN, HRs for first severe hypoglycemia and recurrent hypoglycemia were 1.58 (95%CI 1.13-2.23) and 1.96 (1.33-2.90). In the intensive glycemic management group, HRs for first severe hypoglycemia and recurrent hypoglycemia were 1.10 (0.86-1.40) and 1.24 (0.93-1.65). In summary, CAN was independently associated with higher risks of first and recurrent hypoglycemia among adults with type 2 diabetes, with the highest risk observed among those on standard glycemic management.
Arnaud D. Kaze, Matthew F. Yuyun, Rexford S. Ahima, Michael R. Rickels, Justin B. Echouffo-Tcheugui
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