bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ageing promotes non-remitting experimental autoimmune encephalomyelitis with persistent meningeal inflammation and subpial demyelination in A/T SJL/J mice.
Authors: Le Zuo Michelle Xiao , Ramaglia Valeria , Ma Iris , Gommerman Jennifer L 
Published: February 2023

Abstract
Current therapies for multiple sclerosis (MS) reduce the frequency of relapses but fail to prevent transition from relapse-remitting into progressive MS. Subpial demyelination, meningeal inflammation and neurodegeneration are hallmarks of progressive MS, however there is no single animal model that mimics all these features. Adoptive transfer of proteolipid protein (PLP)-primed Th17 cells into young (~12 weeks old) SJL/J recipient mice induces experimental autoimmune encephalomyelitis (EAE) characterized by subpial demyelination associated with meningeal tertiary lymphoid tissues (TLTs), however young mice develop remitting, non-progressive disease. Since age is a risk factor for transitioning to progressive MS, we hypothesized that adoptive transfer of PLP-primed Th17 cells into old (~12 months old) SJL/J recipient mice would promote a progressive phenotype. Indeed, transfer of cells into aged recipient mice resulted in a non-remitting EAE compared to young recipients despite a similar ability to produce T cell derived cytokines in the CNS at peak disease. However, old mice showed persistent meningeal inflammation as evidenced by more B/T cell rich TLTs in the meninges compared to young mice, and developed increased CNS pathology (subpial demyelination, microglia/macrophage activation, glial limitans disruption, axonal injury, loss of synapses), whereas young EAE mice had recovered most of the pathology seen at peak of disease by day 25 post-transfer. In summary, our model provides an opportunity to assess how subpial demyelination associated with meningeal inflammation impacts the transition from relapse-remitting to progressive MS in a single animal model.
TRAF3 enhances type I interferon receptor (IFNAR) signaling in T cells through modulation of PTPN22
Authors: Hornick Emma , Wallis Alicia Michelle , Houtman Jon , Bishop Gail A 
Published: February 2023

Abstract
T cell responses are critical for successful resolution of many infectious and non-infectious challenges. Robust T cell activation and acquisition of effector functions relies on receipt of at least three signals: 1) antigen recognition by the T cell receptor, 2) co-stimulation, and 3) cytokines. TNF receptor-associated factor 3 (TRAF3) is an adapter protein with diverse cell type- and receptor-specific functions, that regulates signals one and two of conventional T cell activation. In this study, we examine the role of TRAF3 in signaling downstream of the potent signal three cytokine, type I interferon (IFN I). Work from our laboratory has shown that in other contexts, TRAF3 regulates cytokine receptor signaling by facilitating association of phosphatases with JAKs at the cytokine receptor. We therefore hypothesize that TRAF3 regulates IFNAR signaling in T cells through affecting recruitment of the phosphatase PTPN22 to the IFNAR complex.
We investigate the role of TRAF3 in IFNAR signaling using a TRAF3-deficient human T cell lymphoma line and T cells from a T cell specific TRAF3 knockout mouse (T-Traf3−/−). TRAF3−/− T cells display a marked defect in STAT1 activation, leading to defects in IFN-stimulated gene expression and CXCL10 secretion. We show TRAF3 and PTPN22 association with JAK1 and IFNAR1 upon IFN I stimulation in WT T cells, and increased association of PTPN22 with JAK1 and IFNAR1 in TRAF3−/− T cells. Inhibition of PTPN22 restores IFNAR signaling in TRAF3-deficient cells to near WT levels. Together, these data indicate that TRAF3 modulates IFNAR signaling by modulating PTPN22 association with the IFNAR signaling complex, broadening our understanding of the crucial signals that drive T cell activation and polarization.
Impact of aging on monocyte subset production by bone marrow progenitors
Authors: Goodridge Helen Sara , Barman Pijus K , Shin Juliana , Wu Di , Kang Seokjo 
Published: February 2023

Abstract
Monocytes can patrol the circulation or be recruited into tissues to become macrophages or monocyte-derived dendritic cells (moDCs). We previously showed that monocytes arise via two independent pathways in mouse bone marrow: Granulocyte-Monocyte Progenitors (GMPs) produce neutrophils and monocytes, and Monocyte-DC Progenitors (MDPs) yield monocytes and conventional and plasmacytoid DCs (cDCs and pDCs). Notably, both pathways produce monocytes that can differentiate into macrophages, but moDCs arise exclusively via the MDP pathway. We also showed that the microbial stimuli LPS and CpG promote monocyte production by GMPs and MDPs, respectively. We are now investigating how aging impacts the balance of monocyte production by GMPs and MDPs. scRNAseq analysis revealed elevated Cd74 and H2 gene expression by steady-state classical monocytes from old mice compared to young mice, with a larger proportion of monocytes expressing these genes. Consistent with this, we observed proportionally more monocytes expressing CD74 and MHCII in the bone marrow and circulation of old mice by flow cytometry, and a higher yield of CD11c+ MHCII+ moDCs in GM-CSF cultures of MDPs and monocytes from old bone marrow. These findings are indicative of elevated moDC production during aging, perhaps reflecting the more inflammatory microenvironment. In ongoing studies, we are investigating whether imbalanced monocyte production by the GMP and MDP pathways underlies increased moDC production during aging.
Developing a model of thymic regulatory T cell development with single-cell RNA sequencing
Authors: Owen David L. , LaRue Rebecca , Farrar Michael A. 
Published: February 2023

Abstract
CD4SP thymocytes that receive moderate to strong TCR signals upregulate either FOXP3 or CD25, generating distinct FOXP3lo or CD25+ Treg progenitor (TRP) populations, respectively. Stimulation of these TRP populations with IL-2 induces co-expression of CD25 and FOXP3, completing thymic Treg differentiation. The alterations in gene expression that drive these respective Treg differentiation programs, as well as the identification of agonist selected cells within conventional CD4SP thymocytes remain unclear. To address these questions, we performed single-cell RNA-Seq with paired TCR sequencing of conventional and Treg lineage thymocytes, including recirculating Tregs. Interestingly, we found that IL-2 was exclusively produced within the most immature CD25+ TRP undergoing agonist selection. TCR analysis demonstrated that some TCRs were enriched in CD4SP receiving agonist stimulation that gave rise to Tregs, or were subjected to negative selection, while others were excluded from this pathway. Finally, we found several distinct subsets of recirculating Tregs, likely pointing to a variety of functions these cells play in thymic homeostasis and function. We are currently carrying out spatial transcriptome studies to identify the specific localization of distinct Treg intermediates within the thymus. We are using these combined single cell data sets to generate a comprehensive model of thymic Treg development.
CCN3 aggravates intestinal inflammation in inflammatory colitis through regulating NLRP3 inflammasome in macrophages
Authors: Wei Yingying , Duan Lihua , Zhong Jixin 
Published: February 2023

Abstract
CCN3 is one of member in CCN family that regulates several cellular activities including cell adhesion, proliferation and migration. However, the role of CCN3 in the pathogenesis of inflammatory bowel disease (IBD), an idiopathic intestinal disease characterized by chronic inflammation of the gastrointestinal tract, remains unclear. Herein, we established a DSS induced colitis model that mimic human inflammatory bowel disease by using the CCN3 conditional knock-out mice (LysMCre-ccn3f/f). We found that the mortality and colitis disease score were significantly reduced in LysMCre-ccn3f/f mice, compared to the control group (LysMCre). To further evaluate the contribution of macrophages and neutrophils to the protective effect of CCN3 deletion on colitis, we separately depleted macrophages and neutrophils in these mice before colitis induction. The difference in disease severity between these two groups was abolished after the depletion of macrophages, but not neutrophils, suggesting that CCN3 expression in macrophages plays a critical role in intestinal inflammation. In addition, we found that the production of IL-1b and expression of NLRP3 in LysMCre-ccn3f/f bone marrow-derived macrophages (BMDM) were significantly lower than those in LysMCre, indicating that NLRP3 inflammasome activation may be involved. In conclusion, our data provide a direct evidence that CCN3 may play a role in colitis by regulating NLRP3 inflammasome activation in macrophages.
Increased Expression of Toll-like Receptor 2 mRNA after Facial Nerve Injury in Rat
Authors: Park Dong Choon , Min Hye Kyu , Lee Jae Min , Kim Young Il , Kim Sang Hoon , Yeo Seung Geun 
Published: February 2023

Abstract

Objectives:
The aim of this study was to determine whether TLRs mRNA is expressed in the distal facial nerve after facial nerve injury.

Methods:
The adult male Sprague-Dawley with a body weight of 200–250g underwent injury of unilateral facial nerve. Crush or cutting injury was given at the midpoint between the facial nerve trunk and the facial nerve branch. The whisker movement of vibrissae muscle was examined 4 and 14 days after facial nerve injury. The normal facial nerve on the left side and the damaged facial nerve on the right side were taken under the inhalation anesthesia and real-time polymerase chain reaction was performed.

Results:
In the whisker movement of vibrissae muscle, the crush group and the cutting group showed worse scores on the 14th day than the 4th scores in each group (p&lt;0.05). On the 4th day of injury, the expression of TLR 7 mRNA was highest in the crush group, and on the 14th day of injury, the expression of TLR 7 mRNA was highest in the cutting group. On the 14th day of injury, the expression of TLR 2 mRNA was significantly higher in the cutting group than in the control group (p&lt;0.05), on the 4th day of injury, the expression of TLR 9, 13 mRNA was significantly lower in the crush and cutting groups than in the control group (p&lt;0.05).

Conclusions:
The expression of TLR 2 mRNA in the distal facial nerve after facial nerve injury in the cutting group was significantly higher than that in the control group, but the expressions of TLR 9 and 13 mRNA in the crush and cutting groups were significantly low. Therefore, TLR mRNA may be involved in facial nerve damage and regeneration.
Tertiary lymphoid organs drive disrupted gut to lymph node communication through association with collecting lymphatic vessels
Authors: Czepielewski Rafael Sanguinetti , Erlich Emma C , Onufer Emily J , Young Shannon , Saunders Brian , Han Yong-Hyun , Wohltmann Mary , Wang Peter L , Kim Ki-Wook , Kumar Shashi , Hsieh Chyi-Song , Yang Ying , Scallan Joshua P , Zinselmeyer Bernd , Davis Michael J , Randolph Gwendalyn J 
Published: February 2023

Abstract
The concept that impaired lymphatic flow during the progression of Crohn’s disease, a major form of inflammatory bowel disease, emerged decades ago, but remains unresolved. In Crohn’s disease, tertiary lymphoid organs (TLOs) are associated with collecting lymphatic vessels (CLVs) of the mesentery that govern lymph outflow from the intestine. Whether TLOs affect lymph transport is unknown. In the TNFDARE mouse model of Crohn’s-like ileitis, TLOs formed at valve regions which supported lymphangiogenic outgrowths to the TLOs. Photoconversion approaches to study cell trafficking indicated that TLOs received immune cells traveling from the intestine but scarcely allowed their egress, effectively trapping DCs, B, and T cells. Using adoptive transfer of microbiota-dependent TCR we found reduced overall Tregs differentiation and their presence shifted from the lymph nodes to TLOs, altering intestinal-induced responses. Strikingly, although anti-TNF therapy dampens gut inflammation, TLO are refractory the therapy. Moreover, passage of soluble fluorescent tracer through TLO-rich CLVs was also impeded, indicating transport defects were intrinsic to the CLVs. Indeed, lymph flow diverted at TLO to neighboring CLV branches, where dysfunctional valves allowed lymph return to the gut wall, accompanied by lymph leakage at the TLOs. Culturing lymphatic endothelial cells with TNF demonstrate that the cytokine alone can reduce key genes found in lymphatic valves. These data indicate that TNF disrupts lymphatic valve maintenance pathways, promoting formation of mesenteric TLOs that broadly impair lymph transit of molecules and cells from the intestine, impairing immune surveillance of the mucosal barrier, altering homeostasis.
Farnesoid X receptor regulates macrophage activation and recruitment to the lung following exposure of mice to nitrogen mustard.
Authors: Banota Tanvi , Murray Alexa , Sowinski Amanda , Kong Bo , Guo Grace L , Laskin Jeffrey D , Laskin Debra L 
Published: February 2023

Abstract
Nitrogen mustard (NM) is a toxic vesicant known to cause acute lung injury which progresses to fibrosis. This is accompanied by the accumulation of pro-inflammatory/cytotoxic M1 macrophages and anti-inflammatory/pro-fibrotic M2 macrophages in the lung. Farnesoid X receptor (FXR) is a bile-acid activated nuclear receptor involved in lipid homeostasis; it has also been shown to exert anti-inflammatory activity. In these studies, we analyzed the role of FXR in regulating macrophage accumulation and activation in the lung following NM exposure. Male and female wild type (WT) and FXR−/− mice were treated with PBS (control) or NM (0.08 mg/kg) via intratracheal instillation. Lung tissue and bronchoalveolar lavage (BAL) fluid were collected 3, 14, and 28 days later. NM caused histopathologic alterations in the lung including inflammatory cell infiltration, septal damage, and epithelial thickening, which were more prominent in FXR−/− mice relative to WT mice at all post exposure time points. This correlated with aggravated increases in BAL protein and cell content. Flow cytometric analysis revealed pro-inflammatory macrophages were most abundant in BAL 3 days post NM, a response more pronounced in FXR−/− mice. In male but not female mice, increases in proinflammatory macrophages persisted in the lung for at least 28 d post NM. In contrast, while anti-inflammatory macrophages also increased in the lung following NM administration, no differences were observed between WT and FXR−/− mice. These findings demonstrate that FXR modulates proinflammatory macrophage responses to NM in a sex-dependent manner and suggest a potential new target for the development of therapeutics to blunt mustard vesicant induced lung inflammation and injury.
NLRP3 inflammasome activation in macrophages is mechanosensitive
Authors: Almgren-Bell Alison , Joshi Hemant , Todd Elizabeth M. , Morley Sharon Celeste 
Published: February 2023

Abstract
Macrophages are innate immune cells that activate the NLRP3 inflammasome to induce inflammatory cytokine IL-1b production and pyroptotic cell death to combat infections. Dysregulated NLRP3 activation escalates inflammatory diseases under mechanical stress, such as ventilator induced injury (VLI), liver fibrosis, acute lung injury (ALI), and idiopathic pulmonary fibrosis (IPF). Macrophages reside in tissues via anchoring to the extracellular matrix (ECM), and change in adhesiveness tunes their inflammatory response via a process known as “mechanotransduction”. However, the underlying mechanism of how mechanical signaling regulates the NLRP3 inflammasome is not fully known. We have found that the NLRP3 inflammasome pathway in macrophages is sensitive to altered stiffness of the culture surface. We cultured bone-marrow derived macrophages (BMDMs) on collagen-coated polyacrylamide gels or silicone gels mimicking physiological tissue stiffness. We observed that NLRP3-induced IL-1b release was smallest on the softest gel (elastic moduli 0.2 kPa) and increased with a stiffer gel (64 kPa). Additionally, macrophages displayed increased adhesiveness and spreading on stiffer gels, indicating enhanced mechanical force. Further examination of how adhesion based-mechanotransduction modulates NLRP3 signaling will help in understanding inflammatory diseases associated with changing adhesive microenvironments such as lung fibrosis. We propose that increased stiffness during lung fibrosis exerts mechanical stress on macrophages and may promote NLRP3 inflammasome activation. Elucidating the mechanosensitivity of the NLRP3 inflammasome will aid in identifying treatment for such inflammatory diseases.
Antigen presentation by CNS-resident microglia and macrophages regulates CD8 T cell infiltration of the brain during central nervous system (CNS) infection
Authors: Goddery Emma , Fain Cori , Lipovsky Chloe , Jin Fang , Hansen Michael , Johnson Aaron J 
Published: February 2023

Abstract
CD8 T cell responses are essential for clearance of infections in the CNS but contribute to neuropathology. T cell interaction with antigen presenting cells (APCs) at CNS barriers is thought to allow activated antigen-specific T cells to infiltrate the CNS during neuroinflammation. However, the role of CNS-resident APCs during CD8 T cell infiltration of the CNS is unclear. To address this, we utilized Theiler’s murine encephalomyelitis virus (TMEV) and Plasmodium berghei ANKA (PbA) to assess the role of APCs during CD8 T cell responses to CNS infection in mice. During infection, we observed robust upregulation of MHC class I on microglia and brain associated macrophages (BAM). Microglia and BAMs were located in close proximity to inflamed vasculature where antigen presentation to T cells could occur. Thus, we hypothesized that microglia and BAMs are critical APCs for CNS infiltration of antigen specific CD8 T cells. To test this, we generated mice with inducible deletion of MHC class I on microglia and BAMs by crossing CX3CR1creERT2 mice with H-2Db or H-2Kb floxed mice (Db cKO or Kb cKO). We found that brain infiltrating virus-specific CD8 T cells were reduced in Db cKO mice compared to controls during TMEV infection, while peripheral priming of T cells was unaffected. Conversely, antigen-specific CD8 T cell infiltration was not impacted in Kb cKO mice infected with TMEV-OVA257–264. In Db cKO mice, brain-infiltrating CD8 T cells were increased during PbA induced experimental cerebral malaria (ECM), indicating a potential inhibitory role for CNS APCs. These results demonstrate that local antigen presentation by microglia/BAMs can both positively and negatively regulate CD8 T cell infiltration of the brain in discrete neurologic disease models.
TLR9 Knockout in Non-Hematopoietic Cells Protects Mice From Influenza/MRSA Super-infection
Authors: Rich Helen Eva Adams , Martínez-Colón Giovanny , Warheit-Niemi Helen , Gurczynski Stephen , Moore Bethany B 
Published: February 2023

Abstract
Millions of people worldwide are infected with influenza each year, with tens of thousands of deaths yearly in the United States alone. A significant contributor to mortality from influenza is bacterial super-infection from nasal colonizers including S. aureus. Paradoxically, mice lacking the bacterial DNA sensor TLR9 have reduced morbidity and mortality from MRSA super-infection during influenza, concurrent with reduced proinflammatory cytokines in BAL. Surprisingly, macrophages from influenza-infected TLR9−/− mice display increased MRSA phagocytosis and killing compared to macrophages from WT mice. However, bone marrow chimeras reveal that loss of TLR9 on structural (non-hematopoietic) cells is sufficient to reduce bacterial burden to the level of whole-body TLR9−/− mice, while loss of TLR9 in hematopoietic cells does not reduce bacterial burden. Thus, we hypothesize that reduced bacterial recognition by structural cells due to lack of TLR9, mediated by a lower proinflammatory cytokine response, protects animals from influenza/MRSA super-infection. Interestingly, TLR9 may also impact the immune response to influenza through recognizing host mitochondrial DNA. Our data show that influenza induces tlr9 in a wide range of structural and immune cells. Others have shown that influenza induces ER stress, and that influenza infection causes the release of mtDNA into the cytoplasm of lung structural cells. Moreover, others have shown that mtDNA upregulates tlr9 in human lung epithelium. Together, these data suggest that influenza increases mtDNA release inside lung structural cells, which stimulates tlr9 expression in intact lung epithelium, priming the lung for an overexuberant response to bacterial infection.
Pulmonary infection interrupts acute cutaneous wound healing through disruption of chemokine signals
Authors: Crane Meredith , Xu Yun , Monaghan Sean F. , Hall Benjamin M. , Albina Jorge E. , Henry William L. , Tran Holly , Jordon Alexander R.D , Chhabria Karisma , Carlsen Lindsey , Jamieson Amanda M 
Published: February 2023

Abstract
Individuals who are hospitalized with traumatic injuries are susceptible to nosocomial pneumonia. While the effect of the injury on pulmonary infection has been examined in many contexts, it is less well understood how lung infection affects healing wounds. To address this, we examined the outcomes of laparotomized patients with and without pneumonia using the American College of Surgeons NSQIP database. Individuals who developed pneumonia were twice as likely to experience wound dehiscence compared to those without pneumonia. We hypothesized that the immune response could not to meet the demands of competing inflammatory insults in the skin and lungs. To examine this, we developed murine models of post-operative lung infection. Mice were wounded by the dorsal subcutaneous implantation of polyvinyl alcohol (PVA) sponges or tail skin excision, then infected intranasally with Klebsiella oxytoca. PVA sponge wounds allow for the examination of cellular and cytokine responses during acute wound healing, while wound closure can be measured with the tail skin excision model. Pulmonary infection led to rapid suppression of wound IL-1α, IL-1β, and chemokines. This was followed by decreased accumulation of innate leukocytes in the wound and delayed wound closure. In contrast, lung antibacterial responses were not affected by the presence of surgical wounds. Wound healing in infected mice could be rescued by the addition of the chemokines CCL2 and CXCL1; however, this treatment caused a delay in bacterial clearance in the lungs. These data suggest that the immune response is not fully equipped to respond to disparate and competing inflammatory insults, which could have implications beyond the setting of post-operative pneumonia.