bluuebunny/crossref_metadata_2025_split huggingface dataset:
An intact C-terminus is required for the antimicrobial effects of CCL28 in host defense from oropharyngeal candidiasis
Authors: Huppler Anna R , He Jie , Volkman Brian F , Grayson Mitchell H 
Published: January 2023

Abstract
Oropharyngeal candidiasis (OPC) is an opportunistic infection caused by the commensal fungus Candida albicans. There is an urgent need for new therapeutic candidates to manage mucosal infection and prevent progression to high mortality disseminated candidiasis. The T helper 17 (Th17)-associated cytokines IL-23 and IL-17 are crucial for immunity to OPC. However, our recent work indicates the current model of IL-17-mediated defense is insufficient to completely explain susceptibility to OPC. CCL28 is a CC chemokine with antimicrobial peptide (AMP) activity that has a potential role in oral host defense. CCL28 is most abundant in the salivary gland and has in vitro antimicrobial activity against multiple pathogens including C. albicans. Little is known about the in vivo function or regulation of CCL28 in defense from infection. In the current study, we explore the motifs of CCL28 contributing to AMP activity and the relationship with OPC. We demonstrate that C. albicans killing by CCL28 at physiologic concentrations can be eliminated by truncation of the C-terminus. The N-terminus of CCL28, which is required for receptor binding, is dispensable for anti-fungal activity. In an in vivo model of OPC in mice, application of recombinant CCL28 reduces oral fungal burdens in immunodeficient mice. Ccl28 gene expression in salivary gland is suppressed at baseline in mice susceptible to OPC. Our results indicate that the CCL28 flexible C-terminal domain is an important functional motif for anti-Candida AMP activity, CCL28 treatment reduces mucosal fungal infection in vivo, and CCL28 may be a component of host defense from infection. CCL28 is a promising candidate for mucosal immunity and future development for treatment of Candida infections.
Nanoscopic characterization of immunogenic b-glucan exposure on Candida species pathogens
Authors: Neumann Aaron Kurt , Lin Jia , Graus Matthew , Wester Michael J , Lidke Keith 
Published: January 2023

Abstract
The cell walls of Candida spp. are composed largely of polysaccharides. Here we focus on β-glucan, an immunogenic cell wall polysaccharide whose surface exposure is masked from the innate immunoreceptor Dectin-1 to evade immunity. Previous research suggested that the physical presentation geometry of β-glucan may determine whether or not it can be recognized by Dectin-1. We used super resolution imaging to measure the fine structure of glucan exposure on C. albicans cell walls before and after glucan unmasking with the antimycotic drug caspofungin. Most exposed glucan on C. albicans yeast and hyphae exists as single Dectin-1 binding sites. Caspofungin-mediated glucan unmasking results in nanoscale remodeling of glucan exposures, resulting in increased density and size of glucan exposure sites. The less studied pathogen C. glabrata exhibits significantly greater glucan exposure than C. albicans in type strains, but recent clinical isolates of C. glabrata have lower exposure, suggesting that C. glabrata also masks its glucan. We used C. glabrata cell wall mutants to define the role of N-mannan structure in maintaining glucan masking. The less complex N-mannan structures of mutant strains provided poorer glucan masking, increasing the density of nanoscale glucan exposure sites. a-(1,6)-mannan backbone length was a major structural determinant of glucan masking, while a-(1,2;1,3)-mannan side chain density was less critical to masking function. This work provides the first characterization of changing glucan exposure nanostructure at the pathogenic cell wall surface that participates in host-Candida interaction. Further studies will examine the functional impact of glucan nanostructure on Dectin-1 activation.
MyD88 suppresses IL-10 and IL-17 production in response to obligate intracellular Ehrlichia infection
Authors: Kader Muhamuda , Alaoui-El-Azher Mounia , Kode Bhushan , McArthur Morgan , Shinde Apurva , Wells Alan , Ismail Nahed 
Published: January 2023

Abstract
Ehrlichia is an obligate intracellular gram negative bacterium that target macrophages, and causes the potentially fatal human monocytic ehrlichiosis (HME). In murine models of fatal ehrlichiosis (FE), Ixodes ovatus Ehrlichia (IOE) inhibits autophagy, suppresses protective acquired immunity, and causes immunopathology and toxic shock syndrome. Innate Ehrlichia detection by TLR2 mediates host resistance, while NOD2 signaling confers host susceptibility to FE. Recently, we have shown that deficiency of type I interferon receptor (IFNaR) phenocopy NOD2 deficiency in IOE-infected mice, implying a contribution of both NOD2-IFNaR pathways to susceptibility to FE. However, how TLR2 mediates protective function against Ehrlichia is not clearly defined. Here, we investigated the role of MyD88, the main adaptor molecule for the TLRs in host response to virulent IOE using MyD88 knockout mice (MyD88−/−). Our data showed that, MyD88−/− mice have an impaired bacterial clearance, increased liver injury, and a heightened mortality when compared to infected wild type (WT) mice. Increased bacterial load in MYD88−/− mice correlates with decreased levels of TNF-α in both in vivo and in vitro {serum and IOE- infected bone marrow-derived macrophages (BMM)}, and increased frequency of splenic CD4+ T cells producing IL-10 and IL-17. Protective anti-Ehrlichia immunity and minimal pathology in WT mice infected with low virulent Ehrlichia species correlates with a high Th1 response, but a low frequency of IL-10 and IL-17 producing splenic T cells, suggesting that IL-10 and IL-17 may play pathogenic roles in host defense against Ehrlichia. Together these data suggest that MYD88 plays a protective role in ehrlichiosis via suppression of IL-10 and IL-17.
Endoplasmic Reticulum Aminopeptidase I-driven Production of IL-18 and IL-1β Protects from Severe Intestinal Inflammation and Mortality during Experimental Colitis
Authors: Aldhamen Yasser Ali , Alyaqoub Fadel S , Pepelyayeva Yuliya , Rastall David P.W. , Raedy Ashley , O’Connell Patrick , Pereira-Hicks Cristiane , Godbehere Sarah , Amalfitano Andrea 
Published: January 2023

Abstract
Altered endoplasmic reticulum aminopeptidase 1 (ERAP1) function has been linked to many pathological conditions that are characterized by chronic inflammation such as Ankylosing spondylitis (AS), however, a role for ERAP1 in colitis has not been described. Notably, AS patients are known to develop colitis. However, the exact molecular mechanism that predisposes AS patients to intestinal inflammation has not been defined. We previously demonstrated that ERAP1 deficiency alters innate immune responses during pathogen recognition. In addition, we also demonstrated that autoimmune disease-linked variants of ERAP1 activate the NLRP3/caspase-1 inflammasome pathway. Previous reports showed that mice deficient for NLRP3 inflammasome components are highly susceptible to dextran sodium sulfate (DSS)-induced colitis. Here, we hypothesized that ERAP1 may modulate the susceptibility of animals to DSS challenge, due to ERAP1’s impact on innate immune responses. We show that mice deficient for ERAP1 (ERAP1−/−) were highly susceptible to DSS-induced colitis as compared to WT mice. This process was associated with decreased IL-1β and IL-18 production in ERAP1−/− mice, resulting in increased mortality rates and severe intestinal inflammation. Assessment of the intestinal inflammation marker, Lcn-2 revealed potent increases in Lcn-2 in DSS-treated ERAP1−/− mice as compared to WT controls. Furthermore, utilization of ERAP1/β2m double-knockout mice revealed that these responses are mediated by a mechanism that was independent of antigen presentation by ERAP1. These results demonstrate that ERAP1 mediates a protective function during colitis, a function that we correlated with its ability to allow production of IL-18 and IL-1β.
Lineage-specific ablation of retinoic acid synthesis impacts on the development of gut-tropic regulatory T cells and oral tolerance
Authors: Lee Yu-Chi , Li Jiannan , Deng Jie , Noelle Randolph J 
Published: January 2023

Abstract
Oral tolerance is a multifaceted process that leads to systemic unresponsiveness to orally administrated antigens. Successful establishment of oral tolerance relies on induction of antigen-specific gut-tropic regulatory T cells (Tregs). Retinoic acid (RA), the active metabolite of vitamin A, is critical for the induction of gut-homing receptor on T cells and differentiation of Foxp3+ Tregs. Current paradigm, developed from in vitro experimentation, suggests that CD103+ RA-producing dendritic cells (DCs) are critical for mediating mucosal tolerance. However, in vivo evidence supporting this statement is lacking, due to the challenge of lineage-specific ablation of RA. We developed a novel mouse model to ablate RA synthesis in defined cell lineages and evaluate the requirement of RA for the migration, retention and stability of gut-tropic Tregs in different intestinal compartments. We found that RA regulates the development of gut-tropic Tregs cells in a step-wise process by lineage-specific up-regulation of gut-homing receptors. Furthermore, evaluation of the establishment of oral tolerance in an oral Listeria infection model revealed that suppression of immunity against Listeria was less efficient when RA synthesis is ablated. Collectively, this is the first study that elucidates the role of RA for oral tolerance in vivo, and offers novel insight into how RA fine-tunes the balance between gut immunity and tolerance.
The integrin αvβ8 promotes activation of TGFβ by human peripheral monocyte and intestinal macrophage populations
Authors: Travis Mark A , Kelly Aoife , Shuttleworth Elinor , Fenton Thomas , Smedley Catherine , Levison Scott 
Published: January 2023

Abstract
Transforming growth factor beta (TGFβ) plays a key role in maintaining immune homeostasis, both preventing inflammation and promoting tissue repair. The cytokine is secreted as an inactive complex, with the function of TGFβ tightly regulated at the level of its activation. Our previous work in mice has demonstrated a crucial role for an integrin, αvβ8, in activation of TGFβ in the immune system. This pathway appears especially important in the intestine, with important functions in regulating T-cell response via integrin αvβ8 expression in dendritic cells and regulatory T-cells. However, how TGFβ is activated to regulate the human immune system is poorly understood. Here, we show that, in humans, integrin αvβ8 is highly expressed on blood monocytes, which promotes activation of TGFβ by these cells. When monocytes are differentiated to macrophages, high integrin β8 expression and TGFβ-activating function is observed on the more tolerogenic (M2-like) macrophages versus inflammatory (M1-like) macrophages. In both monocytes and macrophages, expression of β8 is upregulated by specific bacterial TLR ligands, suggesting that stimulation of the cells may promote their ability to activate TGFβ. In addition to peripheral immune cells, intestinal lamina propria mononuclear cells express high levels of integrin αvβ8, with increased levels seen in patients with inflammatory bowel disease. Highest levels of integrin αvβ8 are seen on a population of CD14+CD33+CD64+ cells, corresponding to intestinal macrophages. Thus, our data suggest that expression of integrin αvβ8 on monocytes may play an important role in the induction and function of anti-inflammatory macrophages in the intestine via TGFβ activation.
Over-expression of CD200 protects mice from dextran sodium sulfate induced colitis
Authors: Gorczynski R. M , Chen Zhiqi , Yu Kai , Zhu Fang 
Published: January 2023

Abstract
CD200:CD200 receptor (CD200R) interactions lead to potent immunosuppression and inhibition of autoimmune inflammation. We investigated the effect of “knockout” of CD200 or CD200R, or over-expression of CD200, on susceptibility to dextran sodium sulfate (DSS) - induced colitis, a mouse model of inflammatory bowel disease (IBD).
Acute or chronic colitis was induced by administration of dextran sodium sulfate (DSS) in four groups of age-matched C57BL/6 female mice: (1) CD200-transgenic mice (CD200tg); (2) wild-type (WT) mice; (3) CD200 receptor 1-deficient (CD200R1KO) mice; and (4) CD200-deficient (CD200KO) mice. The extent of colitis was determined using a histological scoring system. Colon tissues were collected for quantitative RT-PCR and Immunohistochemical staining. Supernatants from colonic explant cultures and mononuclear cells isolated from colonic tissue were used for ELISA.
CD200KO and CD200R1KO mice showed greater sensitivity to acute colitis than WT mice, with accelerated loss of body weight, significantly higher histological scores, more severe infiltration of macrophages, neutrophils and CD3+ cells, and greater expression of macrophage-derived inflammatory cytokines, whose production was inhibited in vitro (in WT/CD200KO mouse cells) by CD200. In contrast, CD200tg mice showed less sensitivity to DSS compared with WT mice, with attenuation of all of the features seen in other groups. In a chronic colitis model, greater infiltration of Foxp3+ regulatory T (Treg) cells was seen in the colon of CD200tg mice compared to WT mice, and anti-CD25 mAb given to these mice attenuated protection.
We conclude that the CD200:CD200R axis plays an immunoregulatory role in control of DSS induced colitis in mice.
OASL1 deficiency promotes antiviral protection against genital herpes simplex virus type 2 infection by enhancing type I interferon production
Authors: Lee Heung Kyu , Oh Ji Eun 
Published: January 2023

Abstract
Type I interferon (IFN) interferes with virus replication, promotes antiviral responses, and controls innate and adaptive immune responses to certain viruses. Recently, we reported that 2′-5′ oligoadenylate synthetase-like 1 (OASL1) negatively regulates type I IFN production by inhibiting the translation of the type I IFN-regulating master transcription factor, IRF7. Notably, while OASL1-deficient mice induce robust production of type I IFN and are resistant to systemic viral infection, the effects of OASL1 during localized viral infection has not been studied. To this end, we investigated the role of OASL1 during mucosal HSV-2 infection of the genital tract. Oasl1−/− mice exhibited better survival rates than wild type (WT) mice following intravaginal HSV-2 infection, and suppressed virus replication more efficiently despite comparable recruitment of effector immune cells. Moreover, Ly6Chigh monocytes, and not pDCs or other cell types, displayed enhanced production of type I IFNs in Oasl1−/− mice in response to HSV-2 infection. Furthermore, cytotoxic T cell responses including IFN-γ production were accelerated in Oasl1−/− mice after mucosal HSV-2 infection. Collectively, these results demonstrate that OASL1 deficiency promotes antiviral immunity against local mucosal viral infection and suggest that OASL1 could be a therapeutic target for treatment of HSV-2 infection of the genital mucosa.
HIV infection impairs CD8+ resident memory T cell frequency in cervical mucosae
Authors: Pattacini Laura , Baeten Jared , Lingappa Jairam , Lund Jennifer 
Published: January 2023

Abstract
A critical challenge in establishing a cure for HIV is the elimination of reservoirs of infection. A proposed approach is to reactivate HIV replication in infected cells and eliminate them by eliciting functional CD8+ T-cells. Due to their location and rapid and efficient response, CD8+ resident memory T cells (TRM) represent an ideal candidate, but their frequency and localization in HIV-infected subjects had not been evaluated.
Therefore, we quantified frequencies of TRM cells by immunohistochemistry detection of CD8 and CD69 in cervical tissues from 5 HIV-infected and 5 non-infected women. In addition, migration assays of peripheral blood mononuclear cells (PBMC) from HIV-positive and negative donors were performed by plating one million PBMC on the top of a migration chamber placed in a well seeded with confluent HeLa cells. After 24 hours, cells that migrated to the bottom chamber were collected for flow cytometry evaluation.
In cervical tissues, TRM numbers and frequencies were significantly different in basal membranes (0.93% in HIV-negative versus 0% in HIV-positive subjects, p=0.006), whereas no differences were seen for total CD8+ T cells. Moreover, in samples from HIV-positive subjects, lower frequencies of CD8+ CD69+ CD103+ T cells were detected between the cells migrated to the bottom chamber in samples from HIV-infected subjects (0.86% versus 3.54%, p=0.002, in HIV-negative versus HIV-positive). In HIV-positive donors, the frequency of CD4+ CD69+ CD103+ expressing CCR5 was significantly lower than for HIV-negative, while expression of CXCR3 and CCR7 were comparable.
We propose that HIV impairs frequencies of TRM in the cervical mucosa at least in part by reducing CD8+ T cell migration through a CCR5-mediated mechanism.
Validation of Th17 Cell Differentiation from Peripheral Blood CD4+ T Cells Through Assessment of mRNA Expression and Cytokine Secretion using Microplate Reading and Cellular Imaging
Authors: Holderness Kathryn , Crossett Tracee , Larson Brad , Taubner Annegret 
Published: January 2023

Abstract
CD4+ T cells signal and regulate an immune response to pathogens after interacting with an antigen-MHC complex. This activation causes the cells to differentiate into distinct phenotypic and functional effectors, collectively referred to as T helper cells (Th). One such differentiated T cell subset includes the pro-inflammatory T helper 17 (Th17) cell subset. These cells can be beneficial to the host during infection, as they amplify ongoing inflammation by inducing expression of tumor necrosis factor-α. CD4+ T cells that differentiate into Th17 cells are uniquely characterized by production of the pro-inflammatory cytokine, IL-17.
T cells isolated from peripheral blood mononuclear cells and selected for CD4 are differentiated into Th17 cells using a cocktail of specific antibodies and cytokines. The procedure to create and confirm this differentiation can be labor and time intensive.
Here we demonstrate a validated, robust method to differentiate peripheral blood CD4+ T cells into functional Th17 cells using a bead-based activation technology. A novel, cell-imaging multi-mode reader can be used to image phenotypic differences between cells exposed to the antibody/cytokine cocktail and control cells as differentiation proceeds. Creation of fully functioning Th17 cells was then confirmed by assessing IL-17F mRNA levels using a fluorescence RNA in situ hybridization assay, in addition to IL-17 secretion using a homogeneous, bead-based immunoassay technology. The reader was able to perform brightfield and fluorescence imaging steps, as well as laser-based excitation for the secretion immunoassay. The combination provides a comprehensive solution for the creation and validation of this important class of helper CD4+ T cells.
Quantification of multiple human immune checkpoint molecules using antibody array technology
Authors: Huang Ruo-Pan , Peck Hannah , Yen Haw-Han , Huang Ruochun , Mao Yingqing 
Published: January 2023

Abstract
Immune checkpoint molecules play an important role in T cell functionality after TCR/MHC signaling. Blockade of two B7/CD28 family checkpoint molecules, CTLA-4 and PD-1 have already demonstrated superior efficacies in treatment for a variety of malignancies. Recently, the US FDA approved one anti-CTLA-4 monoclonal antibody (ipilimumab, 2011) and two anti-PD-1 monoclonal antibodies (pembrolizumab 2014, and nivolumab 2014) for the treatment of advanced melanoma. Other immune checkpoint molecules have been increasingly considered as new targets for cancer immunotherapy. To facilitate better identification of novel targets and elucidation of the checkpoint blockade, simultaneous detection of these pathway molecules in complex biological samples is essential. With antibody array technology, a novel checkpoint molecule array was developed for quantitative measurement 10 of the most important B7/CD28 family checkpoint molecules including B7-1/CD80, B7-2/CD86, B7-H1/PD-L1, B7-H2/ICOSL, B7-H3, CD28, CTLA-4, ICOS, PD-1, and PD-L2/B7-DC. Antigen-specific capture antibodies were fixed on glass slides with a non-contact arrayer, and multiplex ELISA detection of these proteins was achieved through laser fluorescence detection. All the markers could be detected at pg/ml level. The array was validated by cross reactivity and media recovery tests, and was further validated by conventional ELISA testing of normal human sera. In summary, our system provides a powerful, efficient, and low-cost tool for immunology research and biomarker discovery.
Biomarker Development for Cancer Immuno-oncology/Immunotherapy: Simultaneous Digital Counting of Nucleic Acids and Proteins at 800-plex
Authors: Warren Sarah , Dennis Lucas , Fling Steven , Danaher Patrick , Pekker Irena , D’Amico Leonard , Disis Nora , Geller Melissa , Jacquemont Celine , Kussick Steve , Shine Richard , Bailey Christina , Odunsi Kunle , Cesano Alessandra , Beechem Joseph 
Published: January 2023

Abstract
The ability to measure changes to the DNA, RNA, and protein is crucial to understanding both tumor and immune responses to therapy. NanoString® has pioneered 3D Biology™ – the ability to measure any combination of DNA, RNA, and protein simultaneously using a single detector from a small clinical sample – in order to characterize these complex interactions. Analytes of interest are labeled with fluorescent nucleic acid barcode (via direct hybridization for nucleic acids or antibody conjugated barcodes for protein) and detected via digital counting. This enables quantification of up to 800 analytes from a small sample (50,000 cells for DNA/RNA/protein, or 1–2 5μm FFPE slides for RNA alone). The cancer immunology profiling panel measures 770 mRNAs (unique signatures for 24 infiltrating immune cell types plus extensive immune-signaling pathways) plus 30 key IO proteins.
We present two examples of 3D Biology in action. First, a targeted BRAFV600E inhibitor induces expression changes of immune genes which can be detected at both the RNA and protein levels. Second, in work from ongoing collaborations with the Cancer Immunotherapy Trials Network, clinical samples from patients treated with either mono- or combination immunotherapy can be stratified by gene expression. We also show that gene signatures predict presence of immune cell populations with a high degree of concordance to flow cytometry and immunohistochemistry measurements.
Multiplexed RNA biomarkers have achieved success in predicting patient response to therapy, e.g. NanoString signatures predict response to pembrolizumab (anti-PD-1). Measuring DNA, RNA, and proteins in unison greatly expands the power of biomarker signatures to characterize responses to immunotherapy.