bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interleukin-2 inhibits programmed death-1 receptor expression on CD4+Foxp3+ regulatory T cells (139.11)
Authors: Channappanavar Rudragouda , Twardy Brandon , Suvas Susmit 
Published: January 2023

Abstract
Programmed death-1 (PD-1) is induced in response to TCR stimulation on T cells. In this report, we demonstrate that stimulation of splenocytes (SPCs) obtained from unmanipulated C57BL/6 mice with high (1.0 µg/ml) and low (0.1 µg/ml) dose of plate-bound anti-CD3 mAb resulted in an increased proportion of PD-1+ Treg when measured at different time-points (24h, 48h, 72h and day 4) post-stimulation. Interestingly, addition of recombinant IL-2 in anti-CD3 (0.1 µg/ml) stimulated SPCs culture significantly reduced proportion of PD-1+ Treg in comparison to control cultures with no exogenous IL-2. No significant difference in the frequency of PD-1+ Treg was evident in cultures stimulated with high dose of anti-CD3, irrespective to the addition of IL-2. Since Treg homeostasis in the periphery is largely regulated by IL-2 cytokine, we next determined whether in vivo neutralization of IL-2 can augment PD-1 expression on Treg. Our results showed that 48 h post intra-peritoneal administration of anti-IL-2 mAb in C57BL/6 mice, frequency of PD-1+ Treg significantly increased both in spleen and peripheral lymph nodes when compared to PBS treated control mice. We also determined an age related increase in PD-1 expression on Treg in C57BL/6 that correlates with an age-dependent reduction in IL-2 production in the periphery. Taken together, our results suggest that IL-2 signaling impede PD-1 expression on Treg both under homeostatic condition and in response to weak but not strong TCR stimulus.
Role of Krüppel-like factor 4 (Klf4) in regulation of T cell number and TH-17 differentiation (139.12)
Authors: An Jie , Golech Susanne , Klaewsongkram Jettanong , Huston Gail , Wood William , Zhang Yongqing , Wersto Robert , Becker Kevin , Swain Susan , Weng Nan-ping 
Published: January 2023

Abstract
Krüppel-like factor 4 (Klf4), a zinc finger-containing transcription factor of the Krüppel-like factor family, plays critical role in cell differentiation, growth, and cycle. We report here a role of Klf4 in T cell development and differentiation. The expression of Klf4 was high in thymocytes and resting mature T cells, and was down-regulated in activated mature T cells. In the absence of Klf4, modest but significant reductions of T cell numbers in thymus (~27%) and in spleen (~25%), and a similar degree reduction of spleen CD4 T cells and a less degree loss of spleen CD8 T cells were found in Klf4 deficient mice. Gene expression analysis revealed an alteration of genes involved in cell cycling and proliferation in the absence of Klf4 in thymocytes, implying their role in control of T cell number. Furthermore, we found that significant reduction of IL-17 expressing CD4 T cells (TH-17) during in vitro differentiation in mice absence of Klf4 compared to the wild-type mice. We then demonstrated that Klf4 directly binds the promoter of IL17a but not to the promoter of ROR-γt gene, suggesting that Klf4 directly regulates Il17a in TH-17 differentiation. Together, these findings demonstrate that Klf4 regulates T cell development and TH-17 differentiation.
SHP-1 negatively regulates Th17 cell development. (139.6)
Authors: Mauldin Ileana , Lorenz Ulrike 
Published: January 2023

Abstract
T helper 17 cells (Th17) are a recently identified T cell subset characterized by the production of the inflammatory cytokine IL-17. Activation of the transcription factor STAT3 downstream of IL-6 or IL-21-mediated signaling has been shown to be essential for Th17 differentiation; however how STAT3 is regulated is still poorly understood. We investigated whether the protein tyrosine phosphatase SHP-1, which is recognized for its regulatory role in JAK/STAT signaling, influences Th17 development. Using a genetic mouse model of SHP-1 deficiency, we show that mice homozygous (me/me) or heterozygous (me/+) for the motheaten mutation possess increased numbers of Th17 cells in their Peyer’s patches and intestinal lamina propria compared to wild type (+/+) mice. To gain a better mechanistic understanding of how SHP-1 regulates Th17 development, we performed ex vivo Th17 skewing assays comparing SHP-1-deficient and wild type mice. These studies demonstrate that T cells from me/+ mice are hyper-responsive to IL-6 or IL-21 stimulation compared to +/+ T cells, indicating that SHP-1 negatively regulates IL-6 and/or IL-21-driven Th17 development. Finally, biochemical analyses of primary CD4+ T cells from +/+, me/+ and me/me mice demonstrate that SHP-1 decreases the overall cytokine-induced phosphorylation of STAT3. Collectively, these data suggest that SHP-1 negatively regulates STAT3 signaling downstream of IL-6 and IL-21 and thereby limits Th17 generation.
IL-2 induces perforin mediated cytotoxicity in CD4 cells via STAT5 signaling (139.9)
Authors: Brown Deborah , Canfield Jenna , Lee Sarah , Condon Shirley 
Published: January 2023

Abstract
Cytolytic CD4 T cells have been documented in various chronic infections; however, the factors influencing development of these cells have not been fully elucidated. We have compelling data indicating that IL-2 has profound effects on the differentiation of perforin-mediated cytotoxicity in CD4 effectors. To further dissect the role of IL-2 in CD4 CTL generation, TCR Tg mice deficient in IL-2 or CD25 were used. Low concentrations of IL-2 are necessary in the first 24 h of culture to drive cytolytic CD4 cell differentiation. Cytotoxicity, diminished in the absence of CD25, suggests that signaling through the high affinity IL-2R complex is critical for full cytolytic potential. Phosphorylation of STAT5 peaked at 18-24 h, consistent with duration of exposure to IL-2. IL-7, a common γ chain cytokine that activates STAT5 also induces moderate cytolytic activity. STAT5 binds to the promoter region of perforin and granzyme B and studies are underway to determine whether blocking STAT5 activation can inhibit the development of perforin mediated cytotoxicity in CD4 CTL. Thus, a threshold of IL-2 signaling within the first 48 h is responsible for driving cytolytic activity. Whether this signaling involves STAT5 exclusively, or synergizes with other signaling pathways is a topic of further investigation. These data have implications in the design of vaccines against chronic infections such as HIV, CMV and EBV and in adoptive immunotherapy against certain tumors.
In vivo imaging of monocyte mediated neutrophil extravasation during acute arthritis (140.6)
Authors: Wang Baomei , Runnels Herb , Zinselmeyer Bern , Allen Paul , Miller Mark 
Published: January 2023

Abstract
Rheumatoid arthritis (RA) is an autoimmune disease characterized by progressive inflammation with massive infiltration of leukocytes into the synovium of multiple joints. Although monocyte/macrophage infiltration is a prominent feature and correlated with disease severity, the exactly role of monocytes in the induction phase of joint inflammation is unknown. Using two-photon microscopy, we tested whether monocytes regulate the recruitment of neutrophils during K/B×N serum induced arthritis. We examined neutrophil trafficking dynamics in vivo in LysM-GFP mice using the established i.v. transfer model and a modified in which serum was injected subcutaneously (s.c.) into the footpad. The s.c. model had several advantages including: more synchronized cell trafficking behaviors, shorter disease course and focused inflammation in the affected limb. We found that clodronate-liposome depletion of monocytes impaired neutrophil recruitment in our model at two separate steps. First, transendothelial cell migration was inhibited significantly, leaving many neutrophils stranded along the endothelial surface. Moreover, the cells that managed to extravasate showed defective chemotaxis and localization to the joint. Our results suggest that monocytes serve as key mediators of neutrophil extravasation and may play a second role in controlling the local tissue distribution of neutrophils during arthritis. Key words: Arthritis, Monocyte, Neutrophil, two photon microscopy
Cross-talk between chemoattractant and integrin signaling required for robust calcium flux in neutrophils (140.7)
Authors: Zhang Hong , Ley Klaus 
Published: January 2023

Abstract
Neutrophils are recruited to sites of inflammation in response to chemoattractants including fMLP through a sequence of events involving integrin activation, adhesion and migration into the tissue. Chemoattractant couples through GPCRs to PLCβ, leading to production of DAG and IP3, which in turn induces Ca2+ release from ER. Integrin engagement also elicits a rise in [Ca2+]i. Here, we show that [Ca2+]i in response to fMLP is severely defective in neutrophils lacking β2 integrin (Itgb2-/-). This defect in Ca2+signaling leads to downstream defects in neutrophil spreading, migration and respiratory burst. The Ca2+ signaling defect in neutrophils from Itgb2-/- mice was phenocopied in Plcγ2-/- mice that lack PLCγ2, an enzyme downstream of integrin signaling. Plcγ2-/- neutrophils were still able to arrest under flow, but the adhesion was not productive in that the cells failed to spread. Similar phenotypes were seen in Fgr/Hck, Syk or Tyrob/Fcrγ KO mice lacking molecules known to be involved in integrin signaling. These findings suggest a model in which a small Ca2+signal triggered by PLCβ is followed by an integrin-dependent boost of Ca2+release, resulting in a sufficient level of [Ca2+]i to trigger Ca2+ influx and downstream effector functions. This unexpected cross-talk between chemoattractant receptor and integrin signaling provides a mechanism for robust neutrophil recruitment and explains some of the severe functional defects in mice and patients lacking β2 integrins.
Maternal exposure to diesel exhaust particles alters neonatal dendritic cell DNA methylation profiles and skews function towards pro-Th2 responses. (141.13)
Authors: Fedulov Alexey , Yang Zhiping , Kobzik Lester 
Published: January 2023

Abstract
Neonates of mother mice exposed to allergen are born with increased risk of allergy; their dendritic cells (DC) carry the increased risk phenotype when transferred into normal recipients. These ‘pro-allergic’ DCs have vastly altered DNA methylation profiles. We investigated if epigenetic changes and ‘pro-allergic’ skewing also exist in DCs from offspring of mothers exposed during pregnancy to a pollutant linked to Th2 polarization, diesel exhaust particles (DEP). METHODS: Purified splenic CD11c+ DC of 14-d.o. allergen-naïve offspring from DEP-exposed or vehicle control mothers (n=6/group), as well as from positive control neonates born to OVA-sensitized and challenged females (n=3) were adoptively transferred to 3-d.o. recipients (n=12/group), followed by a low-dose OVA protocol which does not induce responses in normal controls. DCs were also screened for genome-wide DNA methylation changes. RESULTS: Recipients of DCs from neonate donors born to DEP-exposed mothers, but not to vehicle controls, revealed increased airway responsiveness and increased lung eosinophilia, which was similar in magnitude to recipients of DC from neonates born to asthma mothers. DNA methylation testing revealed shared patterns of epigenetic alterations in the DCs from DEP and asthma groups not seen in controls. CONCLUSION: Pregnancy exposure to DEP leads to ‘pro-allergic’ skew in neonatal DC; shared DNA methylation alterations suggest epigenetic involvement in increased allergy risk.
PU.1 expression in T cells is required for the development of IL-9 producing T cells in allergic inflammation (141.14)
Authors: Sehra Sarita , Chang Hua-Chen , Goswami Ritobrata , Han Ling , Nguyen Evelyn , Nutt Stephen , Kaplan Mark 
Published: January 2023

Abstract
The well documented Ets family transcription factor, PU.1 is an important regulator of mast cell, granulocyte and B cell development. Previous studies from our laboratory have identified a novel role for PU.1 in regulating Th2 cell cytokine expression. To further define a role for PU.1 in the development of allergic inflammation in vivo, we studied the development of allergic airway inflammation in mice with a conditional deletion of PU.1 in T cells. Despite the development of normal Th2-responses in the periphery, PU.1 deficient T cells have attenuated allergic inflammation in the lung as compared to wild type mice. To elucidate the mechanism for decreased inflammation in the lung, analysis of cytokines and chemokines from mice that had T cells lacking PU.1, demonstrated significantly decreased levels of IL-9 in the bronchoalveolar lavage fluid concomitant with a significant reduction in the pro-allergic chemokines, CCL17 & CCL22 in lung tissue. We identified PU.1 as a factor that promotes the Th9 phenotype by both repressing Th2 cytokine production and increasing IL-9 production. PU.1 was required for normal generation of IL-9 secreting T cells in vitro and ectopic expression of PU.1 increased IL-9 and chemokine production from Th9 cultures. Together, these data suggest a critical role for PU.1 in generating the Th9 phenotype and in the development of allergic inflammation.
IL-13 is required and sufficient for airway acidification in allergic airway inflammation (141.16)
Authors: Zimmermann Nives , Rothenberg Marc , Kottyan Leah 
Published: January 2023

Abstract
Clinical studies have shown acidification of airways in asthma. Importantly, studies have suggested that acidification contributes to the pathophysiological process. However, the mechanism of acidification is unclear. We developed a novel method for measuring the acidity of mouse airways and demonstrated that mouse airways are acidified during models of allergic airway inflammation. Our studies determined that airway acidification does not develop in IL-13-deficient mice and that IL-13 delivery alone is sufficient to induce airway acidification. There are multiple ways IL-13 could lead to acidification, including direct effects on epithelial cells or through recruitment of inflammatory cells. We demonstrated a partial role for eosinophils in airway acidification as CCR3 and IL-5-deficient mice had decreased extent of airway acidification in allergen-challenged mice. Furthermore, using dimethyl amiloride, a specific inhibitor of the Na+/H+ exchanger, we demonstrated significant inhibition of airway acidification in allergic airway inflammation, suggesting a role for ion (proton) channels. In summary, our studies demonstrate that mouse airways are acidified during allergic airway inflammation. We also showed that the mechanism of airway acidification in asthma involves IL-13-mediated pathways including eosinophils and proton channels. These results have considerable implications for the development of therapies that target airway acidification.
CD23 dependent transcytosis of IgE and immune complex across the polarized human respiratory epithelial cells (141.20)
Authors: Zhu Xiaoping , Palaniyandi Senthilkumar , Li Zili , Conrad Daniel 
Published: January 2023

Abstract
IgE is frequently present in airway secretions and its level can be enhanced in human patients with allergic rhinitis and bronchial asthma. However, it remains completely unknown how IgE appears in the airway secretions. In this study, we showed that CD23 (FceRII) was expressed in the established or primary human airway epithelial cells; its expression was significantly up-regulated when airway epithelial cells were subjected to IL-4 stimulation. In a transcytosis assay, CD23 was capable of transporting IgE across the polarized human Calu-3 monolayer in a bidirectional manner. Furthermore, CD23 was able to transport IgE derived immune complexes. CD23 specific antibody or soluble CD23 significantly reduced the efficiency of IgE or immune complex transcytosis, suggesting a specific receptor-mediated transport by CD23. Exposure of Calu-3 monolayer to IL-4 also enhanced the transcytosis of either human IgE or the immune complex. Transcytosis of both IgE and the immune complex was further verified in primary human airway epithelial cell monolayers. Furthermore, the transcytosed immune complexes were competent in inducing degranulation of the cultured human mast cells. Since airway epithelial cells are the first cell layer to come into contact with inhaled allergens, our study implies CD23-mediated IgE transcytosis in human airway epithelial cells may play a critical role in initiating and contributing to the perpetuation of airway allergic inflammation.
The role of Tyrosine kinase 2 on Th17 development in a murine model of allergic asthma (141.7)
Authors: Übel Caroline , Lehr Hans-Anton , Müller Mathias , Finotto Susetta 
Published: January 2023

Abstract
Mutations of the Janus Kinase Tyrosine Kinase 2 (Tyk2) in humans are associated with hypereosinophilia, Hyper-IgE and susceptibility to viral and mycobacterial infections. This syndrome was found to be the result of defective signaling of both IL 12 and IFNalpha as well as abnormal responses to IL 6, IL-10 and IL-23. Here we describe asthmatic Tyk2 deficient mice suffered from extreme airway eosinophilic inflammation and hyper IgE production compared to wild type mice. As these symptoms are associated with an increase in Th2 cytokines IL-4 and IL-5 in the airways, the major goal of the project is to investigate the role of Tyk2 in CD4+ T cell subset differentiation in the lung in a murine model of acute asthma. Th2 and early Th17 effector T cells are important in establishing the inflammation seen in the airways in this disease. In contrast, regulatory T cells and late developed Th17 T cells have a protective function on it. Under Th17 skewing conditions naïve CD4+ T cells from Tyk2 deficient mice showed an IL-6-dependent defect on Th17 cell development. Consistently, we found hyper-proliferation of Th2 cells associated with a constitutive inhibition of the Th1 and Th17 pathway in the lung of asthmatic Tyk2 deficient mice compared to wild type mice. In summary these data suggest that overexpression of Tyk2 could lead to amelioration of the asthmatic symptoms because this would suppress the pathogenic disease-specific CD4+ T effector cells in the lung.
Prolyl isomerase Pin1 controls TGF-β-Smad signaling and pulmonary fibrosis (142.12)
Authors: Shen Zhong-Jian , Braun Reudi , Xie Qifa , Chu Haiyan , Love Robert , Stodola Levi , Malter James 
Published: January 2023

Abstract
Normal pulmonary function requires precise control over the content and composition of the extracellular matrix (ECM). During the pathogenesis of lung fibrosis, a net increase in ECM content displaces epithelial cells and causes severe reductions of pulmonary function. This process is often associated with elevated levels of TGF-β1 which enhances ECM production by fibroblasts. However, the signaling mechanisms that coordinate ECM production remain unclear. Here, we show that Pin1, a peptidyl-prolyl isomerase which isomerizes pSer/pThr-Pro peptide bonds, reciprocally controls the production of pro- and anti-fibrogenic ECM. Pin1 knockout mice treated with bleomycin, which induces pulmonary fibrosis by elevating TGF-β1, showed significantly attenuated expression of collagens (I, III and V), TIMPs (TIMP1 and 4) and fibrogenic cytokines (TGF-β1, IL-1β and CTGF) but increased MMPs (MMP2 and 3). In primary lung fibroblasts, Pin1 was required for TGF-β1-induced phosphorylation and subsequent nuclear transactivation of Smad3. These functions were mediated by TGF-β1 dependent interactions of Pin1 with inhibitory Smad6. In Pin1 knockout cells, Smad6 remained predominantly cytoplasmic, likely attenuating Smad3 phosphorylation and transcriptional activity. These data support and extend our previous observations that Pin1 blockade in vivo significantly reduced total collagen deposition in the lungs of animal models of asthma and lung transplantation.
β-tubulin-induced autoimmune hearing loss exacerbates in IL-10-deficient mice and restores by IL-10 gene transfer (143.10)
Authors: Zhou Bin , Zhou Yixuan , Habiby Kermany Mohammad , Cai Qing , Yoo Tai 
Published: January 2023

Abstract
IL-10 is a potent immunoregulatory cytokine in homeostatic regulation of autoreactive T cell repertoire, experimental autoimmune hearing loss (EAHL) is characterized by Th1 cell-mediated disorder plus down-regulation of IL-10. We hypothesized that endogenous levels of IL-10 function to regulate the severity of EAHL, and exogenous of IL-10 would abrogate EAHL. BALB/c (WT) and homozygous IL-10-deficient mice were underwent β-tubulin immunization to develop EAHL; some β-tubulin-immunized IL-10-deficient mice were intramuscular injected IL-10 DNA. EAHL developed progressively in both WT and IL-10-deficient mice immunized with β-tubulin, and severity of hearing loss in IL-10-/- mice was significantly greater than that in WT animals. However, the hearing function was significantly improved in IL-10 DNA administration group than that in the control group, ABR thresholds are equivalent to naive controls, and histological analysis of cochlear cross section was similar to those of naïve controls. IL-10 DNA administration suppressed autoreactive T cells and reduced expression of IFN-γ, the proportion of regulatory T cells (Treg) of IL-10-treated mice was significantly increased in comparison with control mice. Therefore lack of IL-10 exacerbates hearing loss, exogenous administration of IL-10 improved hearing function. Thus, IL-10 is capable of controlling autoimmune reaction severity by suppressing Th1-type inflammatory production and enhancing the percentage of Treg cells.
The Coagulation Factors, Thrombin and Activated Protein C, can influence the Pathogenesis of Experimental Autoimmune Encephalomyelitis (EAE) (143.26)
Authors: Alabanza Leah , Bynoe Margaret 
Published: January 2023

Abstract
There is accumulating evidence linking coagulation factors with immune-mediated inflammation. Thrombin, the central enzyme in the coagulation cascade, and the anticoagulant, activated protein C (APC), have been implicated in influencing both systemic and central nervous system (CNS) inflammation. Thrombin is known to mediate pro-inflammatory effects while APC can confer anti-inflammatory properties. We set out to investigate the roles of both thrombin and APC in the pathogenesis of Experimental Autoimmune Encephalomyelitis (EAE), the animal model for multiple sclerosis. We examined the mRNA expression profiles of several coagulation factors as EAE progressed. We observed that mRNA expression of coagulation factors that activate thrombin are increased in the brain during acute EAE. Conversely, the mRNA expression of protein C is suppressed as EAE develops. Given that the major pathological component of EAE is the breakdown of the blood brain barrier, we utilized an in vitro system to directly assess thrombin’s effects on the blood brain barrier. We observed that treatment with thrombin upregulated the mRNA expression of adhesion molecules and chemokines in brain endothelial cells. In addition, thrombin increased the migration of cells across the in vitro human endothelial barrier. These data suggest that coagulation factors are potential contributors to the pathogenesis of EAE and multiple sclerosis.