bluuebunny/crossref_metadata_2025_split huggingface dataset:
Irreversible effector CD8+ T cell differentiation is linked to asymmetric, intra-divisional TCF1 silencing
Authors: Lin Wen-Hsuan Wendy , Yen Bonnie , Nish Simone A , Kratchmarov Radomir , Bhandoola Avinash , Xue Hai-Hui (Howard) , Reiner Steven L 
Published: January 2023

Abstract
During specific immune responses, naive T cells give rise to terminally differentiated effector T cells and pluripotent, self-renewing central memory T cells. We recently provided evidence that, after approximately 3 cell divisions, TCF1, a key transcription factor of memory CD8+ T cells, is unequally expressed by sibling T cells undergoing cytokinesis. We now show that repression of TCF1 by one sibling is cell cycle-dependent and subsequently irreversible. Using pharmacological inhibitors, we found that cells which fail to progress through cell cycle are incapable of silencing TCF1. Using a transcriptional reporter of TCF1, we found that cells that extinguish TCF1 expression do not revert to TCF1-expressing cells. Although inhibition of PI3K/mTOR signaling blocks initiation of TCF1 repression, the same blockade fails to alleviate established silencing of TCF1. T cell progeny that maintain TCF1 expression undergo self-renewal and appear to remain pluripotent, while progeny that lose TCF1 expression appear destined to become functional, but short-lived, effector cells. TCF1-expressing cells generated in initial cell divisions, prior to irreversible TCF1 loss, appear to become quiescent, memory-like cells, whereas those cells that retain TCF1 expression when their sibling cells undergo irreversible TCF1 loss have more effector-like characteristics. The unidirectional quality of TCF1 silencing is compatible with a model wherein central memory cells represent cellular progeny that have yet to repress TCF1, rather than descendants of effector cells that lost TCF1-expression. Asymmetric, intra-divisional differentiation may explain the regenerative quality of lymphocyte clones during immunity.
Plasmablasts induced by experimental Plasmodium infection suppress protective humoral immunity through PD-L1
Authors: Guthmiller Jenna , Graham Amy C , Pope Rosemary L , Zander Ryan A , Butler Noah S 
Published: January 2023

Abstract
Plasmodium infections cause malaria, which remains a global public health crisis. Germinal center derived anti-Plasmodium antibody responses are essential for control of blood-stage parasite replication and clearance. However, antibody responses are dominated by extrafollicular, short-lived plasmablasts that secrete low-affinity antibodies. The factors that regulate plasmablast expansion and the contribution of plasmablasts to protective anti-Plasmodium humoral immunity are not well understood. Utilizing experimental murine Plasmodium yoelii infection, we identified that early, splenic plasmablast responses (CD138hi B cells) are dominated by innate B1b (CD43+CD5−) B cells and are comprised of both parasite- and host-specific cells. We also found that CD138hi B cell responses are largely governed by IFN-γ inflammation, not parasite burden. Strikingly, adoptive transfer of CD138hi B cells reduced germinal center B cell class-switching and parasite-specific IgG secretion in Plasmodium infection-matched recipients. Moreover, T follicular helper cells recovered from CD138hi B cell recipient mice were inefficient at promoting germinal center B cell differentiation. In vitro, Plasmodium infection-induced CD138hiB cells suppressed CD4 T cell proliferation. Mechanistically, we linked the in vivo and in vitro suppressive activity of CD138hi B cells to their expression of the inhibitory ligand PD-L1. Together, our data identify that Plasmodium infection-induced plasmablasts suppress the induction of protective humoral immunity during experimental malaria. This knowledge can be used to develop immune-based therapies that limit or prevent innate plasmablast responses.
Human resistin promotes helminth infection-induced tissue inflammation through binding to Toll-like Receptor 4
Authors: Jang Jessica , Wang Spencer , Le Gros Graham S , Lazar Mitchell , Nair Meera G 
Published: January 2023

Abstract
While murine resistin-like molecules (RELM) can modulate the immune response following helminth infections, the relevance of human RELM proteins in helminth infection is unknown. In helminth-infected patients, we found that circulating human resistin is increased compared to non-infected individuals and positively correlated with parasite burdens and proinflammatory cytokines. To examine the function of human resistin, we utilize transgenic mice in which the human resistin gene was inserted. Following infection with the helminth Nippostrongylus brasiliensis (Nb), resistin expression was upregulated in infected tissue, contributing to exacerbated Nb-induced inflammation characterized by monocyte infiltration and production of proinflammatory cytokines. This increased inflammation resulted in elevated Nb egg burdens and delayed worm expulsion. Genome-wide transcriptional profiling of infected lung tissue revealed that resistin promotes expression of proinflammatory cytokines downstream of toll-like receptor signaling, leading us to investigate resistin signaling through TLRs. Using cell binding assays with lung cells, we show that resistin does not bind as efficiently to TLR4−/− monocytes compared to WT monocytes. Furthermore, resistin directly induced TNFα production in bone marrow derived macrophages, but this activation was abrogated in TLR4−/− macrophages. Together, these studies identify resistin as a detrimental factor induced by helminth infections, where it promotes proinflammatory cytokines and impedes parasite clearance through TLR4. Targeting the resistin/proinflammatory cytokine axis may provide new diagnostic or treatment strategies for helminth infection and associated pathology.
Activation of human keratinocytes by Leishmania spp.: divergent effects of Leishmania infantum versus Leishmania major.
Authors: Scorza Breanna , Wacker Mark , Messingham Kelly , Fairley Janet , Wilson Mary E 
Published: January 2023

Abstract
All Leishmania infections are initiated in skin, but clinical manifestations vary greatly with infecting species. Leishmania major (Lm) causes localized cutaneous lesions, whereas L. infantum (Li) causes potentially fatal disseminated disease without skin pathology. Early responses at the skin infection site influence adaptive responses to Leishmania, yet little is known of the role of keratinocytes. We hypothesized that Leishmania induce keratinocytes to produce factors influencing the immune response. Incubation of Li with primary or immortalized human keratinocytes caused a significant increase in pro-inflammatory cytokine transcripts il6, il8, tnfa, and il1b measured by RT-qPCR. However, keratinocytes exposed to five distinct Lm isolates did not induce these transcripts, highlighting a species-specific difference in inflammatory response. Similar to live parasites, Li-derived exosomes induced more il8 mRNA compared to control (p&lt;0.01) or Lm-derived exosomes (p&lt;0.05). Western blotting confirmed NFkB-p65 activation in keratinocytes exposed to Li but not Lm. To examine whether soluble keratinocyte factors influence nearby immune cells, Li-infected human monocytes were cocultured with keratinocytes across a transwell membrane. Soluble products of Li-exposed keratinocytes improved monocyte control of parasite replication compared with unexposed controls (p&lt;0.01). However, culture with Lm-exposed keratinocytes across the transwell did not affect monocyte Lm infection. These data suggest that (1) activated keratinocytes may increase monocyte leishmanicidal activity and (2) keratinocytes support an early inflammatory environment, uniquely tailored to each Leishmania species, at the infection site.
Cellular and humoral immune response in human Chagas’ disease after treatment with Benzonidazol
Authors: Rodrigues Virmondes , Llaguno Mauricio Llaguno , Correia Dalmo , Silva Marcos Vinicius 
Published: January 2023

Abstract
Chagas’ disease (caused by Trypanosoma cruzi) remains a leading neglected tropical disease in the Americas, associated with 546,000 disability adjusted life years and 10,300 annual deaths. Even today there is a lack of studies proving the effectiveness and effects of treatment with benznidazole in chronic patients, as well as its effects on the cellular immune response. Therefore, we evaluate the clinical and immunological changes in chronic chagasic patients treated with benzonidazol after 48 months of therapy. We assessed the variation of anti T. cruzi IgG antibodies and their isotypes, before and after treatment and the production of cytokines and immunophenotypic profile of T lymphocytes after treatment with benzonidazol. We observed that the treatment did not alter the clinical outcome. In patients with cardiac form or with clinical deterioration was observed a decrease of IgG3 specific antibody and an increase in T. cruzi specific IgG1 antibodies. In patients with clinical deterioration, there was a decrease of Th2, Th17 and Treg cells in cultures stimulated with mitogens. We conclude that, in the chronic phase of Chagas’ disease, after 4 years of treatment, a higher number of Th17 and Treg cells are associated with no disease progression.
Follicular dendritic cells modulated by formyl peptide receptor ligands are capable of enhancing the germinal center reaction in mucosal immune system
Authors: Jang Yong-Suk , Kim Sae-Hae , Kim Ju , Kim Yu Na , Park Jisang 
Published: January 2023

Abstract
In various vaccination protocols, induction of germinal center (GC) is one of the critical factors involved in successful immune induction because GC formation results in the production of high affinity antibodies via B cell clonal expansion, somatic hypermutation, and affinity-based B cell selection. Although GC formation in Peyer’s patch (PP) is slowly and spontaneously induced by intestinal microbiota, it is unknown whether follicular dendritic cells (FDCs) in PP directly contribute to the antigen-specific immune response induction. In this study, we found the expression of formyl peptide receptor (FPR-2), a receptor for cathelicidin LL-37 which could play a role as an adjuvant in mucosal vaccine, on FDCs. The interaction between LL-37 and FPR-2 on FDCs promotes the expression of CXCL13 which is closely associated with the GC formation. Based on these findings, we conclude that the adjuvant role of LL-37 in mucosal immune induction is closely associated with the enhancement of GC reaction in PPs by FDC stimulation.
Germinal responses in murine Peyer’s Patches are regulated by a subpopulation of microbiota-induced IL-21high Tfh cells
Authors: Jones Leigh A , Ho Wen Qi , Ying Sze , Ramakrishna Lakshmi , Srinivasan Kandhadayar G , Yurieva Marina , Ng Wan Pei , Subramaniam Sharrada , Hamadee Nur H , Joseph Sabrina , Dolpady Jayashree , Atarashi Koji , Honda Kenya , Zolezzi Francesca , Poidinger Michael , Lafaille Juan J , de Lafaille Maria A Curotto 
Published: January 2023

Abstract
IL-21 is the signature cytokine produced by T follicular helper (Tfh) cells and is vital in driving both the germinal centre (GC) reaction and formation of high affinity antibodies. However, the degree of Tfh cell heterogeneity and function is not fully understood. By utilising a novel IL-21eGFP reporter mouse carrying a diphtheria toxin receptor (DTR)-enhanced green fluorescent protein (eGFP) fusion gene, we identified a subpopulation of highly differentiated Tfh cells within Peyer’s Patches (PPs). This subpopulation demonstrated highest expression of the key Tfh molecules - Bcl6, ICOS and IL-21, and was found within germinal centres and surrounding B cell areas. TCRb repertoire analysis of GFP+Tfh cells revealed that these were polyclonal and closely related to GFP− Tfh cells, indicating selection by common antigens. In vitro stimulation of IL-21eGFP CD4+ cells in the presence of IL-6, TGFb and retinoic acid led to the induction of GFP+ cells that did not co-express IL-17 or Foxp3. Treatment of IL-21eGFP mice with antibiotics led to an ablation of PP GFP+CD4+ cells meaning that the presence of these cells relies on an intact bacterial microbiota. Furthermore, both polyclonal CD4+ T cell and B cell activation is necessary to support the differentiation of GFP+Tfh cells. Finally, GFP+ cell depletion resulted in a reduced frequency of PP GC B cells and IgG1+ cells and small but significant shifts in gut microbiome composition. Therefore, using a new IL-21-reporter mouse we have identified a subpopulation of Tfh cells induced by the gut microbiota and necessary for optimal PP GC and IgG1 responses.
Nanoimaging granule dynamics and subcellular structures in activated mast cells using soft X-ray tomography
Authors: Chen Huan-Yuan , Chiang Meng-Lin , Lin Zi-Jing , Guttermann Peter , Schneider Gerd , Lai Lee-Jene , Liu Fu-Tong 
Published: January 2023

Abstract
Mast cells play an important role in allergic responses. During activation, these cells undergo degranulation, a process by which numerous mediators stored in the granules are released. Granule homeostasis in mast cells has mainly been studied by electron microscopy (EM), where the fine structures of subcellular organelles are partially destroyed during sample preparation. Migration and fusion of granules have not been studied in detail in three dimensions (3D) in unmodified samples. Here, we utilized soft X-ray tomography (SXT) coupled with fluorescence microscopy to study the detailed structures of organelles during mast cell activation. We observed granule fission, granule fusion to plasma membranes, and small vesicles budding from granules. We also detected lipid droplets, which become larger and more numerous as mast cells become activated. We observed dramatic morphological changes of mitochondria in activated mast cells and 3D-reconstruction revealed the highly folded cristae inner membrane, features of functionally active mitochondria. We also observed giant vesicles containing granules, mitochondria, and lipid droplets, which we designated as granule-containing vesicles (GCVs), and we verified their presence by EM in samples prepared by cryo-substitution, albeit with a less clear morphology. Thus, our studies using SXT provide significant insights into mast cell activation at the organelle level.
An update on IgBLAST, a tool for Ig and TCR sequence analysis
Authors: Ye Jian 
Published: January 2023

Abstract
The variable domain of B and T cell receptor is encoded by multiple genes, including the variable (V) gene, the diversity (D) gene and the joining (J) gene. Previously we developed an analysis tool, IgBLAST, for immunoglobulin sequences (http://www.ncbi.nlm.nih.gov/igblast/). Here we describe our recent update on this tool. The new functionalities include capability to analyze T cell receptor sequences (TR), annotating the CDR3 region, extending alignment to 5′ end of the V region, more flexibility in search criteria and providing summarized information to aid large-scale sequence analysis. We use examples to demonstrate these new functionalities and their implications in Ig and TCR sequence analysis.
Antibody immunotherapy targeting a novel B-cell lymphoma secreted biomarker
Authors: Sutkowski Natalie A , Bouchard Mollie , Bryant John Matthew , Sun Wei , Haque Azizul 
Published: January 2023

Abstract
We have used a patented (US 8,745,713) in vitro antibody platform technology to isolate fully human antibodies against a novel B cell lymphoma secreted biomarker, which is an isoform of the Fc Receptor-Like (FCRL) protein family. The FCRL isoform appears to inhibit CD4+ T cell recognition, and consequently would obstruct T cell immunosurveillance of B cell lymphoma. Targeted antibody immunotherapy is now a first-line treatment of B cell lymphoma due to the success of rituximab, a chimeric antibody that binds to and eliminates cells expressing the pan-B cell marker CD20. We envision that antibody targeting the secreted FCRL isoform would have a completely different mechanism of action from antibodies that bind to and eliminate cells expressing tumor antigens. Instead, anti-FCRL would be more analogous to antibodies that target immunoinhibitory molecules like CTLA4, or PD1 and its ligand PD-L1. Antibodies blocking these inhibitory interactions restore T cell function, ostensibly by promoting T cell priming in the case of CTLA4 blockade, and by preventing T cell exhaustion during PD1/PD-L1 blockade. Antibody targeting the FCRL lymphoma biomarker is instead expected to boost CD4+ T cell antigen presentation by DC and other professional APC, allowing for more robust T-cell anti-tumor responses. Furthermore, targeting the secreted FCRL isoform is not expected to have serious side effects like tumor lysis syndrome, nor affect the patients’ normal B cells. Moreover, since the FCRL biomarker was identified in serum of lymphoma patients, a clinical diagnostic screening assay could readily be developed to monitor for tumor progression and treatment response, as well as, identify candidate patients for FCRL targeted antibody immunotherapy.
True Sensitivity of Immunoassays: Are Concentrations of Low Abundance Analytes Real or Artifacts?
Authors: Oberoi Pankaj , Suschak Jessica , Stenglin Martin , Aghvanyan Anahit , Nikolenko Galina , Roy Daisy , Gardner Louis , Lockney Dustin , Shukla Animesh , Porter Erica , Miller Thomas , Biesso Adrianna , Sardesai Laukik , Sivakamasundar Ramou , Mathew Anu , Glezer Eli N , Wohlstadter Jacob N 
Published: January 2023

Abstract
We developed immunoassays with fg/mL detection limits, 100 to 1,000X more sensitive than current ELISA technology. We measured concentrations of low-abundance cytokines and other biomarkers in the serum of healthy donors, and found that these analytes are present at lower concentrations than had been reported in previous studies. This raised the question of how to demonstrate the reliability of immunoassay measurements for analytes present at sub-pg/mL concentrations. To establish whether measured concentrations are due to the true analyte or an artifact, we depleted the analyte from clinical samples by using high quality antibodies conjugated to Dynabeads. We hypothesized that high abundance serum or plasma components that bind non-specifically to immunoassay components would not be depleted, and that the true analyte would be depleted by the antibodies depending on affinity.
IL-2, IL-4, IL-6, IL-10, IL-17A, IL-21, GM-CSF, TSLP, TNF-a, Cardiac Troponin I, and Tau were used as model analytes. The limits of detection achieved for these S-PLEX™ assays ranged from ~0.2 to ~20 fg/mL. Spike recovery and dilution linearity were between 80% – 120%. Depletion experiments were performed with up to six antibodies per assay. All samples could be depleted by high quality antibodies, including antibodies that were not part of the assays. This indicates that the assays measured the true analyte.
In conclusion, using depletion experiments, we demonstrated that our assays are highly specific and measure the correct analytes. This test of “True Sensitivity” can be applied to all assays claiming to measure low abundance biomarkers.
Using transgenic expression of a MHC Class II/peptide restricted T cell receptor in mature CD8+ T cells to target auto-antigen decorated antigen presenting cells for destruction
Authors: Lees Jason R , Nurmukhambetova Saule , Kim Yong Chan , Zhang Ai-Hong , Scott David W 
Published: January 2023

Abstract
CD4+ T cells are thought to be necessary for MS neuroinflammation, coordinating the destructive immune response following recognition of central nervous system (CNS) antigens in the context of MHC class II molecules on professional antigen presenting cells (APC). Recognition of CNS antigens within the CNS is required to drive CD4 re-activation and subsequent production of cytokines and chemokines crucial to the recruitment of secondary immune effector cells. This CD4+ T cell driven recruitment in turn results in induction of immune pathology while also priming APC to enhance future T cell-APC interactions. Recent studies in cancer immunotherapy have defined protocols for inducing expression of chimeric antigen-specific T cell receptors (CAR) in mature CD8 T cells for the purpose of inducing destruction of antigen bearing cells, apparently without modulating the underlying effector profile of the transduced T cell (i.e., CD8 cells are still cytotoxic through perforin and granzymes). Here we detail the use of defined MHC class II/peptide restricted T cell receptor expression in mature CD8 T cells in an effort to target for destruction MHC class II expressing professional antigen presenting cells containing CNS antigen while sparing MHC II negative neurons and oligodendrocytes. Crucially, an effective antigen elimination strategy would not only modulate the cognate antigen recognized by the transgenic TCR but, given the propensity of APC to present multiple antigens derived from the same phagocytized material, should also impact uncharacterized CNS antigen epitopes.
This study examines a novel potential therapeutic modality for its efficacy in neuroinflammation. Supported by NMSS pilot grant PP3361.
Selective inhibition of matrix metalloproteinase-9 reduces clinical severity in a murine model of Multiple Sclerosis via a reduced immune response
Authors: Onwuha-Ekpete Lillian C. , Tokmina-Roszyk Dorota , Fields Gregg B. 
Published: January 2023

Abstract
Matrix metalloproteinases (MMPs) are a family of proteolytic enzymes that mediate the degradation of extracellular matrix components. Their functions are essential for normal physiological processes such as wound healing, but their dysregulation is associated with various pathologies including Multiple Sclerosis (MS). During MS, CD4+ T-cells activated in the periphery penetrate the blood-brain barrier (BBB), recruit immune cells, initiate destruction of the myelin sheath, and cause axonal loss. Experimental Autoimmune Encephalomyelitis (EAE) is a well-established murine model of MS. In EAE, MMP-9 is required for penetration of the BBB and generation of auto-antigens. Recent studies have demonstrated that MMP-9 contributes to normal intracellular function of various cell types including antigen activated T-cells; however, the intracellular role of MMP-9 in immune cell activation during EAE pathogenesis is not known. In our in vitro studies of immune cells we assessed their response to mitogen following treatment with an MMP-9 inhibitor (MMP-9I). We demonstrated that the MMP-9 intracellular activity is important for homeostatic maintenance as well as a robust immune response. Our in vivo studies using MMP9I resulted in reduced disease severity and a reduction in key EAE hallmarks, weight loss and clinical score. Furthermore, proliferation of immune cells in the periphery following disease induction was reduced and the cellular infiltrates across the BBB. These results further emphasize the importance of MMP-9 as a therapeutic target in autoimmune diseases in addition to its well-established extracellular roles. Thus, it presents a two pronged approach to the therapeutic treatment of autoimmunity.