bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ets1 regulates production of dendritic epidermal T cells (DETC) and cooperates with IL17Ra signaling to regulate immune responses to Staphylococcal skin infection
Authors: Battaglia Michael , Sunshine Alex , Luo Wei , Miller Lloyd S , Sinha Satrajit , Wohlfert Elizabeth , Garrett-Sinha Lee Ann 
Published: January 2023

Abstract
Ets1 is a lineage-specific transcription factor regulating lymphocyte differentiation. Mice that lack Ets1 (Ets1 KO) develop autoimmune disease with enhanced B and T cell activation, including increased production of IL-17. To determine if IL-17 contributes to autoimmunity, we crossed Ets1 KO mice to mice lacking the IL17 receptor A subunit (IL17RA KO) to generate double knock out (DKO) mice. We found that loss of IL17RA did not prevent or ameliorate autoimmunity, but that DKO animals exhibited worse symptoms. DKO mice also showed susceptibility to skin infections with Staphylococcal bacteria. To define the molecular mechanisms that might underlie this phenotype, we assessed gene expression in skin of DKO mice and control mice, which showed reduced expression of Skint genes. Skint proteins are involved in γδ T cell development and skin wound healing responses. We examined the presence of subsets of γδ T cells in the skin including dendritic epidermal T cells (DETC), whose role in murine wound healing responses is well described, and dermal γδ T cells that are important for anti-Staphylococcal immunity. Loss of Ets1 leads to a complete absence of DETC in the skin of mice. On the other hand, dermal γδ T cells are present in all genotypes. While DETC are absent from the skin of both Ets1 KO mice and DKO mice, only DKO mice show enhanced susceptibility to skin Staphylococcal infections, indicating that Ets1 and IL17RA regulate additional aspects of skin immunity. We propose that impaired responses to skin Staph infections in DKO mice are driven both by impaired IL17RA signaling and impaired wound healing. We further propose that the chronic bacterial infection in the skin results in enhanced immune activation and enhanced autoimmunity in DKO mice.
Funded by NIH R01 AI122720 and the Lupus Research Alliance.
Lineage analysis defines subpopulations of human lung tissue-resident memory CD8+ T cells
Authors: Williams Mark Elliott , Elliott Jennifer L , Thomas Jeronay K , Kost Kirsten , Laccetti Kristiana , Lobby Jenna L , Mattingly Cameron , Scharer Christopher , Kohlmeier Jacob E 
Published: January 2023

Abstract
Tissue resident memory T cells (TRM) are important for local immunity and recall responses. In contrast to effector and central memory T cells, TRM remain in the tissues and do not circulate throughout the body. CD69 and CD103 expression are distinguishing markers of TRM cells, although TRM cells expressing only one marker, or absent of both markers, have been described, suggesting further heterogeneity beyond these markers. Many of the phenotypic characteristics and transcriptional properties of TRM cells have been defined in animal models, where in vivo labeling can be used to define tissue residency. Therefore, a deeper understanding of what defines human TRM cells and their molecular heterogeneity is necessary. To address this, single-cell multi-omics data of memory CD8+ T cells isolated from human lungs that have been phenotypically subsetted into CD69+, CD69+CD103+, CD69-CD103-, and naive cells were collected and analyzed by scATAC-seq and scRNA-seq approaches. A lineage analysis of these data identified multiple distinct lineages of TRM cells in human lungs. From this, we defined the genes that drive each lineage through their differentiation program, the variable transcription factor motifs that distinguish each lineage terminal state, and estimate the rate of differentiation as the cells transition. In identifying these subpopulations, we can begin to understand the heterogeneity of TRM cells in humans on a molecular level.
Supported by a grant from the NIH/NIAID (75N93019R00028) and a grant from the NIH/NHLBI (R35 HL150803)
Transcriptome and chromatin changes as regulatory T cells expand and contract to IL-2R signaling in vivo
Authors: Moro Alejandro , Gao Zhen , Wang Lily , Yu Aixin , Hsiung Sunny , Ban Yuguang , Yan Aimin , Sologon Corneliu M , Chen Steven , Malek Thomas R 
Published: January 2023

Abstract
Regulatory T cells are essential to maintain peripheral T cell tolerance and require IL-2R signaling for their development and homeostasis. Here, we used mouse IL-2 (mIL-2) and a fusion protein of mouse IL-2 linked to mouse CD25 (mIL-2/CD25) to induce acute, periodic, and persistent IL-2R-dependent signaling in peripheral Tregs in vivo. RNA- and ATAC-seq assessed longitudinal shifts in the transcriptome and chromatin landscape to define the molecular steps associated with IL-2R-dependent Treg activation, expansion, and subsequent contraction in vivo. Analysis of the RNA-seq data revealed that STAT5 and MYC were two critical drivers of IL-2R-dependent signaling in Tregs. Other signaling pathways were also identified that facilitate cell transcription, integration of TCR signaling, cell cycle progression, and growth. Sustained IL-2R signaling by mIL-2/CD25, but not periodic signaling by mIL-2, more effectively supported Treg expansion, oxidative phosphorylation, and development into eTregs. With respect to chromatin remodeling, IL-2R signaling initially preferentially increased accessibility to binding sites and activity of STAT5, whereas more persistent IL-2R signaling favored accessibility and activity of other transcription factors, dominantly CTCF, followed by a genome-wide less accessible chromatin. Our data favor a model whereby persistent IL-2R signaling initially supports more accessible chromatin and active transcription leading to a metabolic shift toward a more energetic type required for Treg proliferation. Subsequently, as IL-2R signaling diminishes, a shift toward less accessible chromatin occurs that facilitates contraction of the expanded Tregs to restore homeostasis.
This research was supported by funding from Bristol Myers Squibb and the NIH (R01AI148675).
Regulatory T cells control Th1 responses to sustain bacterial immunity and skin barrier function
Authors: Singh Tej Pratap , Lovins Victoria , Carvalho Lucas P , Carvalho Edgar M , Grice Elizabeth , Scott Phillip A 
Published: January 2023

Abstract
Commensals actively contribute to homeostasis in the skin, but a perturbation of the skin bacteria leading to a dysbiosis often promotes increased inflammation. How regulatory mechanisms control the degree of inflammation associated with a dysbiosis is unclear. Here we used a Staphylococcus aureus isolate from Leishmania braziliensis patients to study the regulation of the host immune response in the skin and its consequence during cutaneous leishmaniasis. Topical colonization with S. aureus induced type 17 responses with minimal skin inflammation. Analysis of Foxp3+ Treg cells revealed IL-6 dependent accumulation of Blimp-1 expressing RORgt+ Foxp3+ Treg cells in colonized skin, and that may play a protective regulatory role. To test this, we depleted Foxp3+ Treg cells, which resulted in significant inflammation and a higher bacterial burden on the skin. Additionally, there was some decrease in IL-17 responses, but a significant increase in the IFN-γ production from CD4+ T cells. Moreover, blockade of IFN-γ in Foxp3+ Treg depleted mice restored commensal immunity, barrier function and inflammation. In mice infected with L. braziliensis, depletion of Foxp3+ T cells had a minimal effect on lesion development. However, depletion of Foxp3+ T cells in S. aureus colonized and L. braziliensis infected mice resulted in significantly more inflammation and bacterial burden than control mice without altering the parasite burden. Taken together, we identified a role for Foxp3+ Treg cells in limiting inflammatory responses to skin bacteria by controlling production of IFN-γ by CD4+ T cells.
The tuberculosis resistance protein TOLLIP prevents disease progression by regulating the integrated stress response in alveolar macrophages.
Authors: Shah Javeed A , Venkatasubramanian Sambasivan , Plumlee Courtney , Cohen Sarah , Dill-McFarland Kim , Hinderstein Sarah , Altman Matthew , Urdahl Kevin B 
Published: January 2023

Abstract
Genetic variation associated with decreased TOLLIP expression in macrophages is a tuberculosis (TB) risk factor. However, the fundamental mechanisms underlying TOLLIP’s role in TB pathogenesis and macrophage function are unknown. To understand why TOLLIP strongly influences Mtb-macrophage interactions, we infected B6 mice lacking Tollip (Tollip−/−) with Mtb and evaluated lung-resident macrophage function and clinical response. Tollip−/− mice developed worsened Mtb disease with profuse lipid-laden foamy macrophages in their lungs. This phenotype was intrinsic to AM, as Tollip−/− AM, but not other lung-resident macrophage subtypes, from mixed bone marrow chimeras selectively harbored excessive Mtb bacilli and intracellular lipid. Global gene expression analysis of Mtb-infected, Tollip−/− AM demonstrated alteration in dozens of genes consistent with the integrated stress response (ISR), which adapts cells to variable environmental conditions and is associated with TB progression. Administration of mycolic acid, an Mtb cell wall lipid, to Tollip−/− macrophages induced lipid accumulation, ISR, and increased intracellular Mtb burden. Pharmacologic ISR inhibition restored host defense in Tollip−/− mice and improved Mtb outcomes overall. In humans, TOLLIP mRNA expression was increased in caseous TB granulomas, providing translational relevance for our observations. Taken together, TOLLIP deficiency in AMs induces foam cell formation and ISR after Mtb infection, which permits increased replication and drives immunopathology. These findings illustrate a major mechanism by which TOLLIP-deficient individuals are susceptible to TB disease and suggest novel targets for TB host-directed therapy.
Androgen exposure alters the neutrophil response to pyelonephritis
Authors: Hreha Teri , Collins Christina A , Hunstad David A 
Published: January 2023

Abstract
Urinary tract infections (UTIs) in men are uncommon but carry increased risk for severe upper-tract UTI (pyelonephritis) and complications including renal scarring. In preclinical models of Escherichia coli UTI, male C3H/HeN mice uniformly develop high-titer pyelonephritis (most with renal abscesses), while the majority of female C3H/HeN mice resolve renal infection within 7–14 days. We previously showed that this difference in outcomes is testosterone dependent. Here, we find that androgen exposure in female C3H/HeN mice alters the neutrophil response to UTI, increasing the propensity for severe renal inflammation and abscess formation as opposed to bacterial clearance and resolution of infection. Concordant with our prior published results, androgen exposure in C3H female mice given Escherichia coli UTI led to 3-log higher bacterial loads in the kidneys by 14 days post infection. We found that the kidneys of androgen-exposed mice harbored more neutrophils than standard females at baseline and throughout infection, correlated with higher levels of the neutrophil-recruiting chemokine CXCL1 (murine KC) in kidney tissue. In addition, the kidneys of androgen-exposed females were enriched for aged, immature neutrophils (Ly6G+, CD49d+, CD101−). Compared to their mature (CD101+) counterparts, these cells exhibited markers of increased degranulation, altered phagocytic activity, and diminished capacity for efflux from kidney tissue. These data support a model in which androgen-exposed mice, despite an apparently more robust neutrophil presence, fail to control renal bacterial infection due to altered neutrophil functions.
Supported by grants from NIH (R01 DK111541, R01 DK126697, R01 AI158418)
Exposure to Vishniacozyma victoriae elicits airway inflammation and a CD4+ T cell-driven lymphocytic response.
Authors: Rush Rachael E , Blackwood Catherine B , Lemons Angela R , Orandle Marlene S , Croston Tara L 
Published: January 2023

Abstract
Like the pathogenic yeast Cryptococcus neoformans, Vishniacozyma victoriae (syn. Cryptococcus victoriae), a non-pathogenic yeast, has been associated with allergic airway disease. Although V. victoriae is frequently detected in indoor environments, the impact of repeated exposure is currently unknown. In this study, mice were exposed via oropharyngeal aspiration to V. victoriae or C. neoformans every other day for a total of six exposures, and responses were analyzed 1 day and 21 days post final exposure. As expected, repeated exposure to C. neoformans resulted in an increase of myeloid and lymphoid cells in the bronchoalveolar lavage fluid (BALF), granuloma formation with intralesional yeast, and peribronchiolar and perivascular inflammation 1 day post exposure. This response was exacerbated 21 days post exposure as the yeast cells replicated. Repeated exposure to V. victoriae resulted in an increase in eosinophils, Ly6Chi/int monocytes, and CD103+ dendritic cells in the BALF, and mild perivascular and peribronchiolar inflammation 1 day post exposure. Surprisingly, V. victoriae cells were present in the lungs of exposed mice 21 days post exposure, and the response shifted toward a nodular lymphocytic response with an increase of CD4+ T cells in the BALF. Lastly, C. neoformans exposure was predicted to activate antigen presentation, B cell development and Th2 proteomic pathways, whereas V. victoriae was predicted to activate VDR/RXR activation, Granzyme A signaling, and IGF-1 signaling pathways 21 days post exposure. The results of this study suggest that exposure to environmentally ubiquitous V. victoriae may exacerbate allergic airway disease, although not to the extent of exposure to pathogenic C. neoformans.
Interagency Agreement between NIEHS & NIOSH: AES 12007001-1-0-6
Investigating the Three-Way Interaction between Gastric Epithelial Cells, Human Neutrophils, and Helicobacter pylori
Authors: Trujillo Jacqueline , Allen Lee-Ann H 
Published: January 2023

Abstract
Neutrophils are the most abundant white blood cells in humans and are the first line of defense against pathogens with respect to innate immunity. Helicobacter pylori are gram-negative bacteria that infect the gastric epithelium and play an important role in the development of ulcers and gastric cancer. Large numbers of neutrophils are recruited to the gastric epithelium where they become heavily infected. We demonstrated previously that when neutrophils are infected by H. pylori it extends their short lifespan. In addition, these cells display unique characteristic such as nuclear hypersegmentation that are indicative of N1-like subtype differentiation which may increase bacterial virulence. Studies by other groups have examined H. pylori-epithelial cell interactions but notably absent are three-way co-cultures that examine simultaneous interactions of neutrophils with bacteria and gastric epithelial cells. Addressing this knowledge gap is the focus of my project. Specifically, I am investigating the dynamics of infection in these co-cultures and determining whether the infected PMNs alter epithelial cell function or viability. Using immunofluorescence I am determining bacterial localization, analyzing PMN nuclear morphology, and determining the extent of changes in epithelial cell junctions and the actin cytoskeleton over 24 hours. Additionally, I am using flow cytometry, lactate dehydrogenase release assays, western blotting and microscopy to quantify cell death, including apoptosis, to test the hypothesis that infected PMNs are more toxic to the epithelium than the bacteria alone. Ultimately, our studies are expected to advance understanding of the role of neutrophils in H. pylori pathogenesis.
Characterization of immune cells of stressed beta2-adrenergic receptor homozygous knockout mouse model during Chlamydia muridarum genital infection
Authors: Belay Tesfaye 
Published: January 2023

Abstract
The relationship of stress in chlamydia genital disease pathogenesis and its influence on the host immune response remains unknown. Beta2-adrenergic receptor(β2-AR), the major receptor of the stress hormone norepinephrine (NE), is known to impair the function of immune cells. This study was undertaken to determine whether cold-induced stress (CIS) results in differential viability percent of immune cells β2-AR KO and WT C57BL/6J treated with NE, β2-AR agonist(Fenoterol), or antagonist(ICI 118,551), and patterns of cytokine production. CIS was induced by immersing mice in cold water for five minutes daily for 21 days. Total CD4+, CD8+, differentiated bone marrow-derived monocytes were purified by negative selection and treated with chemicals for one hour before proliferation for 48 h proliferation. The vi-cell viability analyzer showed that NE results in a 30 and 40 % decrease in viability of WT C57BL/6J CD4+ T and CD8+ cells, respectively, compared to KO (p&lt;0.05). Similarly, NE and Fenoterol resulted in a 20 and 27% decrease in viability of bone marrow-derived monocytes compared to the β2-AR KO mice. Cells treated with ICI 118, 551 showed the slightest reduction in viability (12%) compared to those treated with NE. ELISA results show decreased IL-4 and increased IFN-g secretion by CD4+ T cells of β2-AR KO compared to WT. The secretion of TNF-a by CD8+ cells and bone marrow cells treated with NE and β2-AR agonist or antagonist was high in all treatment groups. This study provides insights for the first time to better understand the NE-β2-AR pathway during chlamydia genital infection.
Supported by WV-INBRE of NIH Grant P20GM103434 and NIH grant # 1R15AI124156-01 given to BSC.
Nonencapsulated Streptococcus pneumoniae cause Bacteremia through Inhibition of C-Reactive Protein Binding
Authors: McDaniel Larry S , Thompson Courtney , Keller Lance 
Published: January 2023

Abstract
Naturally occurring nonecapsulated Streptococcus pneumoniae (NESp) are found worldwide and can cause invasive infections. In contrast, encapsulated pneumococci that fail to express capsule are rapidly cleared from the blood of infected mice. We previously demonstrated that NESp expressing the Ami-like proteins AliC and AliD are able to evade complement-mediated killing. Data indicated that factor H (FH) failed to bind to NESp, and thus did not reduce complement activation as seen in FH binding pneumococci. Proteomic data have shown that deletion of aliC and aliD altered pneumococcal protein expression. Additionally, NESp expressing AliC and AliD caused invasive pneumococcal disease in C1q-deficient mice. The purpose of this study was to examine the regulated pneumococcal genes in complement evasion by NESp. Flow cytometry was used to examine binding of C3b to NESp. A mouse model of infection was used to investigate complement interaction with NESp in vivo. NESp expressing AliC and AliD were able to persist for at least four days following intravenous infection of mice. Deletion of aliC and aliD resulted in the clearance of NESp within 24 hours post-infection. There was a four-fold increase in C3b deposition on the mutant NESp compared to the wildtype. Choline binding protein AC (CbpAC), a variant of pneumococcal protein A (PspA), was found to have reduced expression in the aliC and aliD deleted mutant. C-reactive protein (CRP) showed increased binding to NESp in which cbpAC was deleted. Regulated expression of CbpAC in NESp is able to overcome the innate immune response and lead to persistence of NESp within the host by reducing C1q deposition and arresting classical complement activation.
Supported by Departmental research funds.
The diversity of beta defensins in lungfish (Dipnoi)
Authors: DeMmon Diego M , Benedicenti Ottavia , Casadei Elisa , Salinas Irene 
Published: January 2023

Abstract
Mucosal surfaces are the first line of defense against pathogens. At these surfaces, mucus containing innate and adaptive immune molecules is constantly secreted to protect the animal host. African lungfish are the extant relatives to all tetrapods and have a dual mode of living, swimming in freshwater during the wet seasons and aestivating during the dry seasons. During terrestrialization, African lungfish produce large amounts of mucus that form a dry cocoon to prevent water loss. We recently reported that the lungfish cocoon acts as a bacterial trapping structure and it is rich in antimicrobial peptides (AMPs), specifically beta defensins (BD). As many AMPs, BDs are small amphipathic molecules and mainly cationic. The goal of this study is to provide a full characterization of BD genes from transcriptomes and genomes of different lungfish species. Using the canonical six cysteine motif from vertebrate BD molecules, we searched for all BD genes Protopterus dolloi transcriptomes, the genomes of P. annectens and Australian lungfish (a non-aestivating lungfish, Neoceratodus forsteri). BLASTs searches identified 9 BD genes in P. dolloi transcriptomes with predicted highly cationic characteristics except for BD-7. Sequence alignment and phylogenetic trees indicate that three P. dolloi BD genes may be an intermediate form of AMP between beta and alpha defensins. Genomic analyses indicate that P. annectens BD genes contain 3 exons and 2 introns similar to all defensin genes. Future studies will determine the tissue distribution and antimicrobial function of Protopterus spp. BD molecules and determine their potential application as alternatives to antibiotics.
Supported by National Science Foundation Integral Organismal Systems (IOS) award # 1938816
Group B Streptococcus does not translocate the gut epithelium of neonatal mice.
Authors: Harlow Olivia S , Greenfield Kara G , Knoop Kathryn 
Published: January 2023

Abstract
Neonatal sepsis remains a leading cause of death in preterm and low-birthweight infants and can be separated into two groups: early-onset sepsis (EOS) and late-onset sepsis (LOS). Previous studies have shown that LOS can result from translocation of enteric bacteria across the intestinal epithelium, resulting in bloodstream infection. Through metagenomic sequencing we have observed, unsurprisingly, potential sepsis-causing organisms such as Escherichia coli, Staphylococcus aureus, Enterobacter cloacae, and Group B Streptococcus (GBS) in the stool of neonatal intensive care unit patients. Our previous work has shown E. coli can disseminate from the intestines via goblet cells in a model of LOS, but how other bacterial pathogens disseminate remains unclear. GBS is often associated with EOS following in utero infections and vertical transmission from the mother during pregnancy and delivery. However, the ability of gut-residing GBS to cause sepsis in a murine model of LOS is still unknown. Here we infected five-day-old mice by oral gavage with different strains of GBS, but we did not observe GBS translocating the intestinal epithelium in the pups, unlike E. coli. We next induced EOS in newborn mice by vaginally inoculating pregnant mice to assess GBS dissemination and compare the EOS model to our LOS model. After in utero infection, most pups were intestinally colonized with GBS and, interestingly, only pups with GBS colonies in the lungs had systemic GBS infections. This data suggests neonates are at risk of GBS infection in utero, but not following delivery, even if GBS colonizes the neonatal intestine. This work could elucidate the pathogenesis of EOS as compared to LOS, leading to a deeper understanding of modes of GBS transmission.
Supported by NIH: DK122187