bluuebunny/crossref_metadata_2025_split huggingface dataset:
Small intestinal Goblet cells and Goblet cell associated antigen passages assist translocation of pathogenic bacteria
Authors: Kulkarni Devesha Hrishikesh , McDonald Keely G , Knoopr Kathryn , Miller Mark J , Newberry Rodney D 
Published: January 2023

Abstract
The intestinal epithelium forms an essential physicochemical barrier that separates luminal bacteria from underlying immune cells of the intestinal mucosa. Appropriate exposure of the immune cells to luminal antigens is crucial to ensure intestinal homeostasis and to respond to enteric infections. We recently demonstrated a previously unappreciated role of small intestinal (SI) Goblet cells (GCs) in delivering luminal antigens across the epithelium by forming goblet-cell associated antigen passages (GAPs) in the steady state. How pathogenic bacteria affect the formation of SI GAPs and the ability of pathogens to use GAPs as a portal of entry is largely unexplored. Here we report that in conventionally housed mice, luminal exposure to invasive Salmonella typhimurium, but not mutant non-invasive S. typhimurium, results in inhibition of SI GAPs within minutes. Moreover, overriding the ability of GCs to sense the pathogen by deleting MyD88 in GCs or inhibiting EGFR activation downstream of MyD88 during S. typhimurium infection allowed GAP formation, suggesting that GC intrinsic sensing of an invasive pathogen to shut off GAPs is a host defense mechanism. Fluorescent wildtype S. typhimurium preferentially localized around and within GCs forming GAPs. Deletion of GCs prevented the translocation of wildtype S. typhimurium to the SI draining mesenteric lymph node following oral infection, indicating that S. typhimurium uses GCs as a portal of entry. These findings identify a role of GC sensing of an invasive pathogen in inhibiting antigen delivery to the immune system and in limiting the translocation of pathogenic bacteria.
Dysregulation of iCD8α cells promotes susceptibility to intestinal inflammation
Authors: Olivares-Villagómez Danyvid 
Published: January 2023

Abstract
iCD8α cells are a population of innate immune cells present in the intestinal intraepithelial lymphocyte (IEL) compartment, characterized by the expression of CD8αα. We have shown that iCD8α cells play a critical role during immune responses in the intestinal mucosa, however, little is known about the role of iCD8α cells during inflammatory processes of the intestines. The thymus leukemia (TL) antigen is predominantly expressed by intestinal epithelial cells and preferentially interacts with CD8aa. We have shown that CD8αα+ IEL from TL-deficient mice have increased cytokine production and proliferation, indicating that TL controls CD8αα+ IEL effector functions. Rag-deficient mice facilitate the study of innate immune cells, and are an excellent model for the study of iCD8α cells because these cells are the only CD8αα+ IEL present in these mice. Here we present evidence showing that TL regulates the functions of iCD8α cells. Using the anti-CD40 antibody model of colitis, we show that TL−/−Rag-2−/− mice lose more weight, have higher mortality, have more colon damage, and present higher levels of pro-inflammatory cytokines (IFN-γ, IL-6 and OPN) than colons from Rag-2−/− mice. Interestingly, we show that colons and iCD8α cells from TL-deficient mice produce more granzyme than colons or iCD8α cells from TL-competent mice. Moreover, stimulation of iCD8α cells with the pro-inflammatory cytokine IL-12 in vitro induces granzyme secretion. Therefore, we propose that the increased colon inflammation observed in TL-deficient mice is due to: a) dysregulation of iCD8α cells by the lack of TL, and b) increased granzyme secretion by iCD8α cells which may serve as a pro-inflammatory signal.
Balance of Commensal Bacteria-Specific Th17 and RORγt+ Treg Cells in Intestinal Homeostasis and Inflammation
Authors: Xu Mo , Yang Yi , Pokrovskii Maria , Galan Carolina , Littman Dan R 
Published: January 2023

Abstract
A number of Helicobacter species, including Helicobacter hepaticus, have been isolated as the etiological agents of ulcerative inflammatory bowel disease and cancer in their respective hosts. H. hepaticus induces severe Th17-Th1 mediated colitis in a number of immuno-compromised mouse strains, but does not usually cause disease in most wild-type mouse strains. However, how the inflammatory response is carefully contained to be harmless under homeostatic conditions and how perturbations lead to pathogenicity remain elusive questions. To understand this, we developed new research tools, including TCR transgenic mice, as well as MHCII tetramers to interrogate the regulation of H. hepaticus-specific CD4+ T cell function. Interestingly, in contrast to Segmented Filamentous Bacteria (SFB), which induces Th17 cells in the small intestinal lamina propria (SILP) of both IL10+/− and IL-10−/− mice, H. hepaticus mainly induces RORgt+ Treg cells in the large intestinal lamina propria (LILP) of IL-10-sufficient mice, but induces a Th17-Th1 response in the absence of IL-10. We propose that the balance between self/commensal antigen-induced RORgt+ Treg and Th17 cells may be a general strategy to control autoimmune inflammation.
Inducible expression of CXCL1 within the CNS amplifies demyelination in pre-clinical models of multiple sclerosis
Authors: Grist Jonathan Jeffrey , Marro Brett S. , Lane Thomas 
Published: January 2023

Abstract
The functional role of the ELR+ chemokine CXCL1 in host defense and disease in two pre-clinical mouse models of the human demyelinating disease multiple sclerosis (MS) was assessed. Mice in which expression of CXCL1 is under the control of a tetracycline-inducible promoter active within GFAP-positive cells were generated and infected intracranially with the neurotropic JHM strain of mouse hepatitis virus (JHMV) or immunized with myelin oligodendrocyte glycoprotein (MOG)35-55 to induce experimental autoimmune encephalomyelitis (EAE). In both JHMV-induced neurologic disease and EAE, overexpression of CXCL1 by astrocytes resulted in increased clinical disease severity. Immunophenotyping cells infiltrating into the central nervous system (CNS) revealed a selective increase in Ly6G+CD11b+ neutrophils (but not Ly6G−Ly6C+CD11b+ monocytes) present within the CNS. In JHMV infected mice and MOG35-55-immunized mice, the T cell response to antigen with regard to proliferation and cytokine production was not altered, nor was trafficking into the CNS affected. In both models, increased CXCL1 expression within the CNS resulted in increased morbidity that correlated with selectively elevated neutrophil infiltration, diminished numbers of mature oligodendrocytes, and an increase in the severity of demyelination. Neutrophil ablation in CXCL1-transgenic mice reduced the severity of demyelination in mice arguing a role for these cells in white matter damage. Collectively, these findings illustrate that sustained CXCL1 expression amplifies the severity of white matter damage and neutrophils can contribute to this process in two different mouse models of MS.
Vector mediated in vivo induction of antigen-specific regulatory T cells abrogates clinical and histological signs of EAE
Authors: Hoffman Brad E , Keeler Geoffrey D 
Published: January 2023

Abstract
Induction of peripheral immune tolerance requires regulatory T cells (Tregs). Protocols designed to manipulate antigen (Ag) specific-Treg populations in vivo, represent a powerful approach for treating autoimmune disease such as Multiple Sclerosis (MS). It has been shown that Ag-specific Tregs can play a critical role in the protection and recovery of MS, and its animal model, experimental autoimmune encephalomyelitis (EAE). Unfortunately, methods to induce endogenous CNS-targeting Ag-specific Tregs that achieve therapeutic efficacy are lacking.
To address this, we developed an immune tolerance induction therapy using an AAV vector expressing the full coding sequence for the neuro-protein MOG under the control of a strong liver specific promoter. Our data demonstrates that peripheral injection of this vector induces functionally suppressive transgene-specific Tregs, and mice pre-treated with this vector are protected from developing EAE. More notably, when vector is administered during mild to moderate disease, there is a nearly complete reversal of EAE, both clinically and histopathologically. When treatment is withheld until mice exhibit moderately severe EAE, our therapy still significantly reduced the neurological symptoms and clinical score, although to a lesser degree. Thus, to increase efficacy of the vector induced Tregs, a short course of rapamycin treatment was given concomitantly which had a synergistic affect, resulting in a long-term significant reversal of disease. Using our vector platform to deliver full-length proteins offers a superior MHC/HLA independent approach for in vivo induction of Ag-specific Tregs compared to other ex vivo or epitope restricted Treg mediated therapies being investigated.
Towards the repair of marginal liver grafts: Ex vivo Mesenchymal stromal cell perfusion
Authors: Bartczak Agata , Ma Xue-Zhong , Manuel Justin , Zhang Xing-Hua , Cifuentes Juan Andres Echeverri , Linares Ivan , Selzner Markus , Keating Armand , McGilvray Ian 
Published: January 2023

Abstract
More than 25% of persons listed for a liver transplant in Canada die before obtaining a suitable liver graft. This occurs despite the recent inclusion of livers from deceased after cardiac death (DCD) organ donation. Over half of possible DCD livers undergo long periods of ischemia that sensitize the liver to reperfusion injury (HIRI) and render the liver grafts unsuitable (marginal) for transplantation. Mesenchymal Stromal cells (MSC) protect against HIRI by decreasing the production of inflammatory mediators secreted by liver resident macrophages. We hypothesized that MSC-treatment of marginal DCD grafts on an ex-vivo perfusion circuit (NEVLP) would repair HIRI damage. Kupffer Cells (KCs) are central to HIRI: they are activated after reperfusion and release various inflammatory cytokines, including TNFα, which promote hepatocyte death. We have developed a DCD liver graft model to evaluate the potential of MSC treatment. In this model, liver grafts undergo 45-minute warm ischemia followed by 2-hours of cold ischemia before being placed on a normothermic ex-vivo perfusion unit for 6 hours. We found that the infusion of MSCs into the ex-vivo perfusion circuit decreases the levels of TNFα in the perfusate. This data was confirmed in in vitro studies where the co-culture of LPS-activated KC with MSCs decreased the amount of TNFα in culture supernatants compared to KC alone cultures. The levels of TNFα in the supernatant were further decreased in cultures treated with LPS-primed MSCs. We propose that the combination of MSC treatment and NEVLP perfusion of DCD livers will repair HIRI-injured and can be rapidly translated to the clinic to expand the donor organ pool.
Response to extracorporeal photopheresis in chronic graft versus host disease correlates with levels of IL-10 producing regulatory B cells
Authors: Chandra Daniel J , Hosoba Sakura , Giver Cynthia , Waller Edmund K 
Published: January 2023

Abstract
Chronic graft versus host disease (cGVHD) continues to be a major source of morbidity and mortality in allogeneic hematopoietic stem cell transplant (allo-HSCT) patients, and current therapies are limited by severe toxicity and immunosuppression. Numerous studies have confirmed the efficacy of extracorporeal photopheresis (ECP) in the treatment of steroid refractory cGVHD without inducing immunosuppression. Although studies have posited a role for immunoregulatory cells in the mechanism of ECP, the immunological effects of ECP are not completely understood. The purpose of this study was to evaluate the role of IL-10 producing regulatory B cells (Bregs) in ECP, and we hypothesized that patients who responded to ECP would have a higher frequency of Bregs over the course of their treatment. We evaluated 10 patients with various stages of cGVHD who received ECP therapy at Emory University from 2013 to 2015. ECP responders were defined as patients who were able to reduce their steroid dose by 50% within 4 months of starting treatment with stable or improved clinical GVHD scores. By measuring CD19+ IL-10+ cells as a proportion of total lymphocytes, we found that ECP responders had a significantly higher percentage of Bregs at 2 months (mean 3.7 vs. 0.08; p = 0.02) and 4 months (mean 2.2 vs. 0.15; p = 0.02) after initiating ECP compared with non-responders. When analyzing for overall B cell frequency, we found a significantly higher percentage of B cells in ECP responders at 2 months (mean 27.6 vs. 0.47; p = 0.02) and 4 months (mean 10.1 vs. 0.77; p = 0.02) post-ECP. Our results are consistent with studies reporting a Breg defect in cGVHD and suggest that there is a correlation between clinical response to ECP therapy and Breg frequency.
The effect of lymphodepletion on specificity and function of cytomegalovirus-responsive CD8 T cells in transplant recipients
Authors: Higdon Lauren E , Margulies Kenneth B , Maltzman Jonathan S 
Published: January 2023

Abstract
Polyfunctional CD8 T cells produce multiple cytokines and effector molecules in order to control chronic viral infections, such as cytomegalovirus (CMV), a cause of allograft damage in transplant patients. Healthy individuals resolve primary CMV infection rapidly and control viral reactivation with memory T cells. IFNγ production by CD8 T cells protects from CMV, but the role of polyfunctional T cells in immunosuppressed transplant patients is not fully understood. We measured responses to CMV polypeptides IE-1 and pp65 to characterize the effects of T cell depletion on T cell specificity and polyfunctionality. In this study we identified polyfunctionality as co-expression of IFNγ, TNFα, and/or the degranulation marker CD107a. We analyzed T cell responses in pre- to a year post-transplant PBMC samples from cardiac and renal transplant patients. Treatment included anti-viral prophylaxis and 3 drug immunosuppression, with T cell depleting induction therapy in some patients. The 3 normal donors and 12 pre-transplant samples analyzed fall into 3 groups on the basis of IE-1 and pp65 specificity: equal response to both or dominant for either IE-1 or pp65. Almost all cells with exactly two functions were TNFα+. In some patients, lymphodepletion led to an early loss of polyfunctional T cells. However, polyfunctional CD8 T cells returned to pre-transplant levels by day 180. In addition, 3 patients displayed shifts from their pre-transplant IE-1 vs pp65 specificity post-transplant, while specificity was consistent over a year post-transplant in the other 8. In conclusion, pre-transplant TNFα expression is predictive of polyfunctionality, and further study is needed to determine the effect of T cell depletion on fine antigen specificity.
Islet encapsulation with tannic acid-containing nanothin coatings modulates immune responses and restores euglycemia upon islet transplantation
Authors: Tse Hubert Ming , Padgett Lindsey E. , Pham-Hua Dana , Xue Bing , Anderson Brian , Zeiger Michael , Kozlovskaya Veronika , Kharlampieva Eugenia 
Published: January 2023

Abstract
Type 1 diabetes (T1D) is an autoimmune disease resulting in pancreatic b-cell lysis via reactive oxygen species (ROS), pro-inflammatory cytokines, and islet-infiltrating leukocytes. One promising treatment for T1D is islet transplantation, but its clinical application is constrained due to islet availability, adverse effects of immunosuppressants on islet function, and declining graft survival. Islet encapsulation may provide an immunoprotective barrier to aid in preserving function and curbing immune-mediated rejection post transplantation. We previously demonstrated that a cytoprotective nanothin multilayer coating consisting of tannic acid (TA), an immunomodulatory antioxidant, and poly (N-vinylpyrrolidone) (PVPON), curtailed immune responses involved in transplant rejection. We hypothesized that (PVPON/TA) coating may hinder the synthesis of redox-sensitive chemokines that recruit immune cells to sites of islet engraftment and blunt ROS-dependent cues necessary for M1 macrophage differentiation. (PVPON/TA) coatings elicited a 7-fold decrease in M1 macrophage-derived pro-inflammatory chemokines CCL5 and CXCL10, blunted M1 macrophage activation markers, and curbed diabetogenic CD4 T cell migration approximately 2-fold. Importantly, murine islet encapsulation with (PVPON/TA) material restored euglycemia in immunodeficient-diabetic mice post transplantation. Our studies demonstrate that (PVPON/TA) multilayer coatings represent a promising immunomodulatory biomaterial for islet transplantation. Future studies will evaluate the efficiency of PVPON/TA coated islets in curbing hyperglycemia by allotransplantation into diabetic rodent models.
Obese mice exhibit accelerated immune and myeloid reconstitution after congenic hematopoietic stem cell transplantation
Authors: Khuat Lam Tan , Mirsoian Annie , Pai Chien-Chun Steven , Abedi Mehrdad , Murphy William J 
Published: January 2023

Abstract
The obesity rate is increasing in the United States with more than a third of U.S. adults being obese. Obesity is a form of sterile chronic inflammation, termed “meta-inflammation”, which is local, chronic and triggered by metabolical pathways. Therefore, there is a need to uncover the potential role of obesity in the development of immune cell subsets post-HSCT. In this study, we wanted to assess the impact of obesity on immune reconstitution following congenic HSCT in lean and DIO (diet-induced obese) recipients. C57BL/6 mice received lethal radiation dose at 1100cGy and 5 million T cell-depleted bone marrow cells from H2-matched B6.SJL mice. Our data demonstrated that DIO recipients displayed a more rapid and robust reconstitution affecting both myeloid and lymphoid compartments. DIO recipients had increased neutrophils, platelets and total lymphocytes post-HSCT compared to control mice. Colony forming unit-granulocyte macrophage (CFU-GM) assays showed significantly higher numbers in DIO recipients at day 14 post-HSCT. Organ cellularity from thymus, spleen and bone marrow were increased in DIO recipients compared to lean mice at day 14 and 21 post-HSCT. Higher numbers of CD4+CD8+ thymocytes, as well as higher number of NK cells and B cells in the spleen and lymph nodes were also observed. Splenocytes from DIO recipients had greater proliferative ability either after stimulation with concanavalin A or in mixed lymphocyte reaction compared to lean controls. Taken together; these results indicated that obesity results in acceleration of engraftment and donor immune reconstitution.
Human cytokine-induced memory-like NK cells expand in patients with AML and display enhanced anti-leukemia responses.
Authors: Berrien-Elliott Melissa M , Romee Rizwan , Wagner Julia , Rosario Maximillian , Jewell Brea , Schappe Timothy , Leong Jeffery , Abdel-Latif Sara , Willey Sarah , Yu Liyang , Oh Stephen , mulder Arend , Class Frans , Fehniger Todd A. 
Published: January 2023

Abstract
NK cells are innate lymphoid cells that mediate anti-tumor responses. Relapsed/refractory AML patients have a poor prognosis and new therapy approaches are needed. Recently, memory-like properties of NK cells have been discovered, including cytokine-induced memory-like NK cells. Human NK cells briefly pre-activated with IL-12, IL-15, and IL-18 and then allowed to differentiate in vitro have greater re-stimulation responses compared to control cells. We hypothesized that such human memory-like NK cells possess enhanced anti-leukemia functionality. Indeed, memory-like NK cells produced increased IFN-γ in response to primary AML blasts in vitro, compared to controls. Multi-dimensional mass cytometry analyses revealed minimal alterations of memory-like NK cell inhibitory KIR repertoire, and both KIR-ligand matched and mismatched memory-like NK cells responded to primary AML blasts. In the context of a first-in-human clinical trial, allogeneic memory-like NK cells expanded to become the majority of the cells in the blood and bone marrow from AML patients 7–14 days after infusion. Furthermore, donor memory-like NK cells displayed enhanced leukemia-triggered IFN-γ production compared to recipient NK cells in the same samples, and clinical responses have been observed in 3 of 6 evaluable patients. In one patient, mass cytometry revealed expansion of CD3− CD56+ CD8+ NK cells with restricted KIR expression and multiple activating receptors. Deep NK cell immunophenotyping of in vivo expanded memory-like NK cells in additional patients is ongoing. Since memory-like NK cells expand in vivo and display enhanced anti-leukemia functionality, they represent a promising immunotherapy approach for patients with AML.
Generation of catalytic antibodies is an intrinsic property of an individual’s immune system: a study on a large cohort of renal transplant patients
Authors: Mahendra Ankit , Peyron Ivan , Thaunat Olivier , Dollinger Cécile , Gilardin Laurent , Sharma Meenu , Wootla Bharath , Rao Desirazu N. , Padiolleau-Lefevre Séverine , Boquet Didier , More Abhijit , Varadarajan Navin , Kaveri Srini , Legendre Christophe , Lacroix-Desmazes Sébastien 
Published: January 2023

Abstract
The origin and physiopathological relevance of catalytic antibodies is not well understood owing to the fact that catalytic antibodies have been studied in relatively small cohorts of patients with rare diseases and/or without systematic follow-up. In the present study, we have followed the evolution of the levels of catalytic IgG in a large cohort of 100 renal transplant patients over a 2-year period. Prior to transplant, hydrolysis of the generic substrate PFR-MCA was greater for patients’ IgG than for a therapeutic preparation of pooled IgG from healthy donors (6.6±0.9 vs 0.65±0.03 fmol/min per pmol). Renal transplant was marked by a drastic decrease in levels of catalytic IgG over 3 months (6.6±0.9 vs 2.4±0.2 fmol/min/pmol; P&lt;0.0001) followed by a steady increase at 12 months (3.2±0.3 fmol/min/pmol; P=0.015) and further at 24 months (5.1±0.6 fmol/min/pmol; P=0.004). When divided into quartiles based on the rates of IgG-mediated PFR-MCA hydrolysis measured in pre-transplant samples, the IgG catalytic activity in the upper quartile of patients was significantly high both pre-transplant (12.03±1.6 vs 2.7±0.2 fmol/min/pmol, P&lt;0.0001) and 24 months post-transplant (6.8±1.2 vs 4.6±0.7, fmol/min/pmol, P=0.0004). Interestingly, IgG-mediated hydrolysis of a model protein substrate, pro-coagulant factor VIII, did not correlate with that of PFR-MCA prior transplantation, while it did 12 months post-transplant (P&lt;0.0001, R2=0.4). Taken together, our results suggest that the level of circulating catalytic IgG under pathological conditions is an intrinsic property of each individual’s immune system, and that recovery of pre-transplant levels of catalytic IgG is accompanied by changes in the repertoire of target antigens.