bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunological difference in Th1 and Th2 dominant mouse strains in an ICD model. (IRM15P.601)
Authors: Luckett-Chastain Lerin , Calhoun Kaitlin , Kemp Jesse , Gallucci Randle 
Published: January 2023

Abstract
Of reported occupational injury associated with workman’s compensation, contact dermatitis ranks second most prevalent overall. C57BL/6 and BALB/c differ in their immune responses, tending to be either Th1- or Th2-dominant, respectively. Irritant contact dermatitis (ICD) is an acute inflammatory response that can vary among individuals. Therefore; to better characterize ICD, these two mouse strains were utilized. C57 and BALB/c mice were exposed to benzoalkonium chloride, (BKC) or acetone (control) for 3 or 7 days. Multiplex protein analysis showed pro-inflammatory cytokines such as IL-1β, IL-6, TNF-α, IFN-γ, IL-22, and CSFs (GM-CSF and G-CSF) were all significantly upregulated in C57s at Day 3 as compared to BALB/c. Inflammatory cell chemoattractants such as CXCL1, 2, and 10, as well as CCL3, 4, 5, and 7 also displayed higher expression in C57s. Interestingly, it wasn’t until Day 7 that BALB/c mice showed significantly elevated levels of inflammatory mediators such as IL-2, IL-4, IL-5, IL-31, IL-9, IFN-γ, and CCL2 compared to C57. Cytokine mRNA expression also varied between the two strains, but did not necessarily correlate with protein data. In addition, C57 appeared to have worse inflammation than BALB/c as indicated via histopathology. Overall, these results further confirm previous findings in which BALB/c and C57 exhibit different immune responses and may provide a better understanding of dermopathology and allow for specific immunomodulation for therapy.
CIS inhibits effector programs in regulatory T cells (IRM15P.459)
Authors: Yang Xuexian , Zheng Handong , Dong Chen 
Published: January 2023

Abstract
Regulatory T (Treg) cells play an essential role in immune homeostasis. Under the pro-inflammatory settings such as autoimmune diseases, the function of Treg cells is impaired, in which pro-inflammatory cytokine IL-4 and IL-6 are involved in destabilizing Treg cells. However, the pathways that stabilize Treg cells have not been well understood. We have shown that cytokine-induced SH-2 protein (CIS) inhibits STAT3 and STAT6 activation; our current study indicates that CIS is required for stabilizing Treg cells in a Treg cell-intrinsic manner. Cis deficient Treg cells had impaired suppressive activity in vitro. Cis deficient mice on a T helper 2 (TH2) cells-prone background develop lymphadenopathy, splenomegaly and multiple organ inflammation, which is associated with spontaneous loss of Foxp3 expression and gain of TH2 cytokine expression in Treg cells. In addition to its role in cytoplasm, CIS also translocates into the nuclei in Treg cells which may serve as a second mechanism of surveillance for pro-inflammatory cytokine induced STAT6 (and maybe also STAT3) in the nuclei, and therefore contribute to stabilization of Treg cells.
Translational control of TGF-β-mediated Treg cell differentiation by hnRNP E1 (IRM15P.460)
Authors: Ansa-Addo Ephraim , Hussey George , Howe Philip , Li Zihai 
Published: January 2023

Abstract
CD4+Foxp3+ T cells are generated either in the thymus for natural regulatory T cells, or in periphery for inducible Treg cells (iTregs), which differentiate from naïve T cell precursors. Both Tregs express Foxp3 albeit they differ in their plasticity and in their expression of certain genes. Trans­forming growth factor-β (TGF-β) and interleukin-2 are important for iTreg generation and maintenance, whereas proinflammatory cytokines such as IL-4 and IL-6 impair Foxp3 induction. Much has been learned regarding the transcriptional roles of TGF-β in determining the fate of iTregs; however, the limited focus if any on a translational mechanism by which TGF-β regulates the fate of functional T cells is somewhat myopic. We previously showed a novel translational mechanism for TGF-β regulation of EMT in mouse mammary gland epithelial cells whereby hnRNP E1 (E1) binds to a structural, 33-nucleotide TGF-β-activated translation element in the 3’ UTR of target transcripts and represses their translation. In this study, we found that E1 knockdown (E1KD) in naïve CD4+ T cells induces TGF-β signaling and upregulates expression of multiple TGF-β target molecules implicated in iTreg cell differentiation. Furthermore, E1KD CD4+ T cells bypass the need for TGF-β and express Foxp3. This study adds to our knowledge on a hitherto unrecognized translational mechanism by which TGF-β controls iTreg cell fate.
The regulation and role of L-glutamine in B-lymphocyte activation (LYM7P.618)
Authors: Heyse Shannon , Connolly Timothy , Doughty Cheryl , Chiles Thomas 
Published: January 2023

Abstract
B lymphocyte activation is a highly energetic event that promotes cell survival and growth. Aberrant activation of B lymphocytes can lead to disease states such as lymphomas or autoimmune diseases. To meet the metabolic demands of activation, B cells increase nutrient uptake to provide energy and intermediates for macromolecule synthesis. We have investigated the role of L-glutamine, which is emerging as a critical immunomodulatory nutrient; however, the precise role of L-glutamine in B cell growth responses is poorly understood. Depletion of extracellular L-glutamine results in impaired cell growth and proliferation in response to B-cell antigen receptor (BCR) ligation, although, early activation events such as induction of CD86 are unaffected. We show that L-glutamine uptake is induced in response to BCR ligation. This corresponds to an increase in the surface expression of the high affinity L-glutamine transporter, ASCT2, indicating its involvement in L-glutamine uptake. Further, inhibition of ASCT2 by the small molecule N-glutaryl-L-phenylalanine p-nitroanilide (GPNA) caused impaired B lymphocyte activation similar to that observed in response to L-glutamine depletion. The addition of L-leucine abated some of the effects of GPNA treatment on B lymphocyte growth responses, indicating mTORC involvement. These data provide new insight on the requirement of L-glutamine in B lymphocyte activation and suggest a possible underlying mechanism of growth regulation by mTORC.
Histone methyltransferase Ezh2 is critical for activation-induced CD8 T cell proliferation and survival (LYM7P.615)
Authors: Chen Guobing , Subedi Kalpana , Mi Jenny , Shi Alvin , Weng Nan-Ping 
Published: January 2023

Abstract
Ezh2 catalyzes trimethylation of H3K27 and regulates transcriptional repression. It plays a vital role during stem cell development and cell differentiation. Although it is well documented that epigenetic changes regulate gene expression, the epigenetic mechanism during CD8 T cell differentiation are not fully understood. Here, we assessed the role of Ezh2 in CD8 T cell differentiation using Ezh2 T cells deficient mice (Ezh2-loxp/CD4-Cre, Ezh2 KO). The number of CD8+ T cells in the young Ezh2 KO were similar to wild-type (WT) mice. When infected with listeria-OVA, OVA+ CD8 T cells were not increased in Ezh2 KO compared to WT. This deficiency was further confirmed with the adoptive transfer of the OT-1 CD8 Tn cells into congenic mice with infection. We then examined CD8 T cell differentiation in vivo and in vitro. We found that CD8 Tn cells express activation-induced markers and cytokines similarly between Ezh2 KO and WT mice. However, CD8 Tn cells from Ezh2 KO mice showed impaired proliferation and enhanced apoptosis after activation compared to that of the WT mice. Genome-wide transcription analysis confirmed that Ezh2 KO CD8 T cells expressed significantly higher levels of cell cycle and apoptosis related genes than WT after activation. Collectively, these findings demonstrate that Ezh2 is required for repression of the transcriptional programs involved in cell proliferation and apoptosis during CD8 T cell activation and differentiation.
IL-21 signaling modulates the differentiation, distribution, and abundance of CD8 T cell subsets (LYM7P.616)
Authors: Tian Yuan , Cox Maureen , Kahan Shannon , Ingram Jennifer , Bakshi Rakesh , Zajac Allan 
Published: January 2023

Abstract
The activation of naïve CD8 T cells typically results in the formation of effector (TE) cells as well as memory cells that are retained over time. Memory CD8 T cells can be further subdivided into central memory (TCM), effector memory (TEM) and tissue-resident memory (TRM) subsets, which cooperate to confer immunological protection. Using adoptive transfer studies and mixed bone marrow chimeras in which CD8 T cells either do or do not express the IL-21 receptor (IL-21R), we discovered that under homeostatic or lymphopenic conditions IL-21 acts directly on CD8 T cells to favor the accumulation of TE/TEM populations. The inability to perceive IL-21 signals resulted in reduced accumulation of CD8 T cells in various tissues including the small intestine intraepithelial lymphocyte compartment. The reduced fraction of IL-21R-/- CD8 TRM cells in the small intestine also displayed markedly lower levels of the cytolytic effector molecule granzyme B. Notably, IL-21 signaling was associated with the expression of the chemokine receptor CX3CR1 and the integrin α4β7 on circulating CD8 T cells in the mixed bone marrow chimeras. Acute lymphocytic choriomeningitis virus infection overcame the necessity for IL-21 to establish CD8 TE/TEM and TRM subsets. Overall, this study demonstrates that IL-21 modulates the differentiation, accumulation, and function of effector-phenotype CD8 T cells in a context-dependent manner.
Identification of extrinsic and intrinsic factors that specify CD4+ TCM cell fate (LYM8P.626)
Authors: Oestreich Kenneth 
Published: January 2023

Abstract
The expression of the transcriptional repressor Bcl-6 has been commonly linked to the development of both the CD4+ T follicular helper (TFH) and T central memory (TCM) cell types. Here, we demonstrate that in response to decreased interleukin 2 (IL-2) signaling, Bcl-6 expression is increased in effector T helper 1 (TH1) cells. Consequently, this results in the promotion of both TFH and TCM-like gene programs including expression of Il6ra and Il7r. Strikingly, exposure of this potentially bi-potent cell population to interleukin 7 (IL-7) results in a significant decrease in TFH-associated gene expression patterns including that of Bcl6 and Cxcr5, but not in TCM-specific genes including Sell and Klf2. The decrease in the TFH-profile is dependent upon a repressive complex that includes the IL-7 responsive transcription factor Stat5. These data support a model by which IL-7 signaling specifies TCM cell fate by repressing the TFH gene program.
Biomarkers for progression from latent to active tuberculosis identified in multiplexed proteomic assay (SOMAscan™) of human plasma (MPF6P.657)
Authors: Ochsner Urs , Hraha Thomas , Sterling David , De Groote Mary , Wall Kirsten , Janjic Nebojsa , Zak Daniel , Thompson Ethan , Penn-Nicholson Adam , Scriba Thomas 
Published: January 2023

Abstract
Background: Biomarkers of progression from latent to active tuberculosis (TB) would be very useful for targeted treatment or priority enrollment in TB vaccine trials. Methods: A highly multiplexed proteomic assay (SOMAscan) was used to measure over 3000 human proteins in plasma from adolescents infected with M. tuberculosis. We compared proteomic data in longitudinally collected samples (six-month intervals over two years) from 97 individuals, 29 of whom developed active TB (progressors) and 68 matched controls who remained healthy. Bioinformatics algorithms were applied to discover biomarkers of TB risk. Results: Among the top host biomarkers distinguishing progressors from controls were 17 proteins, and these factors were used for model building to predict TB risk. An 8-marker model gave a cross-validated performance of 76% sensitivity and 86% specificity (AUC=0.86). The individual markers had variable responsiveness at time-points closer to TB diagnosis. The model identified progressors up to 540 days prior to TB diagnosis, with elevated logOdds for developing active TB. In contrast, a previously obtained host response signature for active pulmonary TB detected progressors up to 180 days prior to diagnosis. Conclusions: The discovery of TB-risk biomarkers indicates that subjects who eventually progress to TB disease can be identified well before clinical diagnosis of TB, and thus enables potential triage for targeted treatment or priority enrollment in TB vaccine trials.
Loss of chemotaxis gene ΔcheY3 in Borrelia burgdorferi leads to early immune clearance but does elicits a strong antibody response (MPF6P.647)
Authors: Sekar Padmapriya , Novak Elizabeth , Motaleb A. , Wooten Ronald 
Published: January 2023

Abstract
Borrelia burgdorferi (Bb) is a spirochetal bacterium that displays unique endoflagellar motility to efficiently disseminate through dense host tissues, and eventually persist within target tissues to cause Lyme disease. The importance of Bb motility/chemotaxis in dissemination/immune evasion cannot be correctly assessed in vitro, since the complexity of the host tissues cannot be accurately replicated. We assessed the importance of the chemotaxis-associated cheY3 gene on Bb dissemination and immune evasion within intact mouse tissues using our novel intravital microscopy techniques. CheY3-deficient (∆cheY3) Bb possessed similar cellular morphology and growth rates, but moves at lower velocities as wild-type (WT) Bb in murine skin tissues. Notably, GFP-ΔcheY3 were unable to reverse direction, whereas WT display primarily a sequential forward-and-reverse motility pattern. Within skin inoculation sites, ΔcheY3 were cleared by 72-96h post-infection and were not detected in distant tissues ≤day 60 post-infection. Interestingly, ∆cheY3-infected mice generate Bb-specific IgG levels similar to WT-infected animals at 14-28 days post-infection, though levels decrease by day 60. The antibody profile against ∆cheY3 Bb suggests that immunity is generated against many of the same Bb proteins as during WT infection. These findings suggest that cheY3 is essential for Bb persistence and that the attenuated ∆cheY3 Bb may serve as a vaccine to protect against Lyme disease.
Cutaneous leishmaniasis is regulated by Wnt antagonist Dkk-1 from activated platelets (MPF7P.715)
Authors: Bothwell Alfred , Chae WookJin , Ehrlich Allison , Teixeira Alexandra , Goldsmith-Pestana Karen , Maher Stephen , Hwa John , Krause Diane , McMahon-Pratt Diane 
Published: January 2023

Abstract
Cutaneous leishmaniasis is a chronic non-healing skin inflammatory disease present in many countries. Here we show that the Wnt antagonist Dkk-1 is secreted from activated platelets and regulates chronic inflammation to Leishmania (L.) major. We found that L. major infection could rapidly elevate circulating levels of Dkk-1. First, Dkk-1 from activated platelets increased neutrophil-platelet aggregate formation mainly via PSGL-1. Second, the continuously high level of Dkk-1 further directed T cell differentiation into Th2 cells in the draining lymph nodes. Secretion of Dkk-1 was regulated by PKC-alpha and GSK3-beta in human platelets upon soluble leishmania antigen exposure in vitro. Functional inhibition of Dkk-1 using a small molecule inhibitor showed marked inhibition of neutrophil-platelet aggregate formation at early hours of infection and also resulted in decreased parasite burden and amelioration of skin lesions after 6 weeks. In vitro studies demonstrate that Th2 skewing is directed by Dkk-1 via p38 and SGK-1 resulting in elevation of GATA-3 and c-Maf. This coordinated expression of two Th2 cytokine transcription factors resulted in robust production of Th2 cytokines (e.g., IL-4, IL-5, IL-10 and IL-13). Thus, our results demonstrate that platelet-derived Dkk-1 regulates early and late inflammatory responses in cutaneous leishmaniasis.
Deletion of fibrinogen-like protein 2, a novel CD4+ CD25+ Treg effector molecule, leads to improved control of Echinococcus mutilocularis infection (MPF7P.718)
Authors: Lin Renyong , Wang Junhua , Vuitton Dominique , Müller Norbert , Blagosklonov Oleg , Grandgirard Denis , Leib Stephen , Shalev Itay , Levy Gary , Lu Xiaomei , Spiliotis Markus , wen Hao , Gottstein Bruno 
Published: January 2023

Abstract
The proliferation of Echinococcus multilocularis (E. multilocularis) metacestode is dependent on the nature/function of the periparasitic immune-mediated processes. Fibrinogen-like protein 2 (FGL2) was found to be up-regulated after E. multilocularis infection, however little is known about the contribution of this novel CD4+CD25+ Treg effector molecule to the control of a helminth infection. We showed that, as compared to AE-WT mice, AE-fgl2-deficient mice exhibited a significantly decreased parasite load and proliferation activity, associated with increased T cell proliferation in response to ConA, reduced Treg numbers and function, relative Th1 polarization, and increased B cell number and DC maturation. We showed for the first time that FGL2 is involved in negative immune regulation towards a helminth parasite and that IL-17A contributes to FGL2 regulation. By promoting Treg cell activity, FGL2 appears as a key-player in the immune orchestration of the outcome of E. multilocularis infection and measurement of plasma FGL2 levels might be useful to assess disease progression. Furthermore, targeting FGL2 could also be used for the development of novel treatment approaches in alveolar echinococcosis and other diseases caused by parasite pathogens.
Bacterial metabolites reduce intestinal permeability to protect against food allergen sensitization (MUC8P.724)
Authors: Feehley Taylor , Aitoro Rosita , Stefka Andrew , Nagler Cathryn 
Published: January 2023

Abstract
Food allergies are a growing public health concern. Our laboratory has recently identified a consortium of Firmicutes from the Clostridia class that can protect germ free (GF) or antibiotic (Abx)-treated mice against sensitization to peanut. This Clostridia consortium induces an early innate cytokine response in the colonic lamina propria that is characterized by the production of the barrier protective cytokine IL-22. By measuring the concentrations of two immunodominant peanut allergens, Ara h 2 and Ara h 6, in serum post gavage we demonstrated that Clostridia-induced IL-22 is necessary and sufficient to reduce intestinal permeability in neonatal Abx-treated mice. Administration of FITC-labeled dextran molecules of different sizes has further interrogated the effect of Clostridia colonization on intestinal permeability to food allergens. Treatment of GF mice with heat-killed Clostridia did not induce IL-22 or reduce intestinal permeability, suggesting a role for bacterial metabolites in mediating protection. Metabolomic analysis revealed that our Clostridia consortium produces high levels of the short chain fatty acids acetate and butyrate. Administration of acetate or butyrate to GF mice showed that only butyrate induced IL-22 and reduced the concentration of peanut allergen in the blood after challenge. We propose that production of butyrate is one mechanism by which Clostridia can influence intestinal permeability and host susceptibility to allergic sensitization.
Postnatal colonization shapes the immunologic development of the neonatal intestinal barrier. (MUC9P.751)
Authors: Singer Jeffrey , Blosser Emily , Randolph David , Weaver Casey 
Published: January 2023

Abstract
Microbial colonization of the newborn intestines begins immediately following birth and continues gradually over a period of weeks in both mice and humans. Many preterm infants are unable to secure their intestinal barrier against opportunistic pathogens, resulting in Late-Onset Sepsis (LOS). Here we present a novel murine model of Gram-negative LOS that mimics the natural disease course seen in premies-colonization absent tissue destruction, translocation across the intestines, and bacteremia resulting in sepsis and death. We find that maternal exposure to broad-spectrum Gram-negative (Gentamicin), but not Gram-positive (Vancomycin) antibiotics profoundly affects survival following infection with Klebsiella pneumoniae. Concordantly, neonates from Gentamicin-exposed dams show marked decrease in IL-22 production from Innate Lymphocytes and decreased Tumor Necrosis Factor-alpha (TNF-a) from both CD4+ and CD8+ T cells. These results offer a novel model to study bacterial translocation in the neonatal gut and suggest possible mechanisms through which the intestinal barrier is maintained during the physiologic colonization of the mammalian intestines.
Commensal bacteria-induced MyD88 signaling regulates intestinal permeability to food allergen via anti-microbial peptide and mucin production (MUC9P.741)
Authors: Pawar Sandeep , Feehley Taylor , Nagler Cathryn 
Published: January 2023

Abstract
Intestinal epithelial cells (IEC) play a critical role in maintaining the integrity of the mucosal barrier. We have recently shown that germ free mice exhibit increased intestinal permeability to food allergens, suggesting a role for microbiota-derived signals in protecting the barrier. Decreased permeability to the peanut allergen Ara h 6 in mice selectively colonized with a consortium of Firmicutes in the Clostridia class is associated with upregulation of antimicrobial peptide expression (RegIIIβ/γ) and the production of mucins (MUC2/13). RegIIIβ/γ are well known targets of MyD88 signaling. We hypothesized that Clostridia signals through MyD88 in IECs to enhance barrier protection and generated mice lacking MyD88 in IECs (Myd88ΔIEC). Myd88-/- and Myd88ΔIEC mice exhibit increased permeability to Ara h 6, downregulated expression of RegIIIβ/γ in IECs, and reduced production of MUC2/13 in goblet cells. Antibiotic mediated depletion of commensal bacteria exacerbated the permeability defect in Myd88ΔIEC mice and also led to a barrier defect in MyD88-sufficient littermate controls. Colonization with Clostridia rescues this defect in control mice but not in the Myd88ΔIEC mice indicating that signaling through MyD88 in the intestinal epithelium is necessary for bacteria-induced barrier protection. This restricted permeability of the gut limits the access of dietary antigens to the systemic circulation and contributes to protection against allergic sensitization in these mice.
Peptide microarrays for coverage of sequence diversity in monitoring the B cell immune response (TECH2P.911)
Authors: Castro Aaron , Stephenson Kathryn , Neubauer George , Korber Bette , Barouch Dan , Pawlowski Nikolaus , Zerweck Johannes , Reimer Ulf 
Published: January 2023

Abstract
Pathogens such as HIV or other viruses exhibit considerable sequence diversity as a strategy to escape the host immune system. However, sequence diversity is not limited to infectious agents. The increasing application of DNA sequencing indicates diversity between individuals (germ line mutations) and within individuals (somatic mutations) for many proteins. Such mutations can be connected to diseases such as cancer or autoimmune disease. The knowledge of antibody reactivities within individuals against self and foreign antigens is important for diagnosis, patient stratification, prevention and treatment of disease. Here we describe the application of high content peptide microarrays presenting thousands of peptides to be assayed with ~1µl serum sample of a donor to asses the reactivity pattern of antibodies towards a number of given antigens under consideration of sequence diversity using HIV as an example. A library of 6564 overlapping peptides represents the immunogenic fraction of the HIV proteome and covers the majority of the available sequences from the LANL global HIV-1 database. This high content library enables the assessment of antibody reactivity within different individuals independent on the serotype of the infecting HIV-viruses as well as the breadth and depth of antibody binding after boosting the immune system by vaccination. This concept can be easily adapted to other pathogens as well as self antigens such as tumor-associated antigens.