bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gene expression profiling of enhanced lung inflammation during pregnancy (134.54)
Authors: Fedulov Alexey V , Lamoureux Denise , Yang Zhiping , Kobzik Lester 
Published: January 2023

Abstract
Pregnant mice show sustained lung inflammation after exposure to environmental particles, titanium dioxide (TiO2), which are otherwise 'inert' in non-pregnant individuals (Am J Respir Cell Mol Biol. 2008. 38(1):57-67). We sought to characterize the gene expression program that underlies this inflammation by PCR array analysis. Selection of candidate genes for this array was informed by prior genome-wide chip microarray results, amended with hypothesis-driven candidates. METHODS: Pregnant E14 mice and controls received intranasal instillations of 50 ug/mouse of TiO2 particle suspensions or vehicle alone; n=5/group. After 48 hrs lungs were extracted, total lung RNA was isolated and samples were tested by real-time PCR via a custom 96-well PCR array (SABiosciences). Normalized dCt values were analyzed by pair-wise comparisons (ANOVA) and by main-effects tests (factorial ANOVA). RESULTS: Pregnant, but not control mice, show significant upregulation of ten genes (e.g. Itgax, CD4, Igsf6, Tlr2 and Tlr4) and a trend to upregulation of another ~20 genes, with fold change of 1.5-4.0. There is indication of influx of dendritic cells and T-helpers with some evidence of Th2 polarization. CONCLUSION: PCR array analysis identifies a gene expression signature for the enhanced inflammatory response to TiO2 particles seen in pregnant lungs, and suggests effects on adaptive immune responses. 1K99ES015425.
Activation of mouse complement C3 by human C-reactive protein (134.59)
Authors: Singh Sanjay K , Suresh Madathilparambil V , Hammond David J , Takahashi Kazue , Agrawal Alok 
Published: January 2023

Abstract
Human C-reactive protein (CRP), once bound to pneumococcal C-polysaccharide (PnC), interacts with C1q and activates the classical pathway of complement in human serum. In mouse serum also, PnC-bound CRP activates complement, but not through the classical pathway because human CRP does not interact with mouse C1q. This study was undertaken to determine the pathway through which human CRP activates mouse complement and to generate a CRP mutant incapable of activating mouse complement. We found that human CRP could bind to mouse mannose-binding lectins, indicating that human CRP might activate the lectin pathway of complement in mouse serum. Further experiments to investigate whether human serum activates the lectin pathway of complement in mouse serum are ongoing. We next determined the complement C3-activating potential of two CRP mutants, Y175A and L176Q, which do not bind to human C1q. As expected, both CRP mutants did not activate C3 in human seum. However, in mouse serum, the C3-activating potential of the L176Q CRP, but not of Y175A CRP, was drastically reduced compared to that of wild-type CRP. It has been shown previously that human CRP protects mice from lethality following infection with Streptococcus pneumoniae. The L176Q CRP is a useful mutant of CRP to define the contribution of CRP-mediated complement activation in the anti-pneumococcal function of human CRP in mouse models of infection. NIH R01HL071233
Requirements for the binding of C-reactive protein to complement factor H (134.60)
Authors: Hammond David J , Singh Sanjay K , Suresh Madathilparambil V , Pangburn Michael K , Agrawal Alok 
Published: January 2023

Abstract
Human C-reactive protein (CRP) protects mice from lethality following infection with Streptococcus pneumoniae type 3. Because both CRP and type 3 pneumococci are reported to bind to complement regulatory protein factor H, we propose that the factor H-binding capability of CRP may contribute to anti-pneumococcal function of CRP. In this study, we explored interactions between CRP and factor H with the aim to generate a CRP mutant incapable of binding to factor H. Surprisingly, we found that freshly-purified CRP did not bind human factor H. But, in the presence of phosphoethanolamine (PEt), freshly-purified CRP bound to human factor H efficiently in a dose-dependent manner. In contrast, and as reported previously, when an old preparation of CRP was thawed and used, CRP bound to human factor H even in the absence of PEt. Identical results were obtained with murine factor H. We also found that the mutations at the C1q-binding site on CRP did not affect the binding of PEt-complexed CRP to factor H, indicating separate binding sites on CRP for C1q and factor H. The mechanism of action of PEt in the binding of CRP to factor H is unknown; however, it seems that PEt modifies CRP in a way similar to storage-induced modification of CRP. Our findings raise the possibility that CRP, once in contact with a PEt-containing surface, gains factor H-binding specificity to modulate the complement attack on factor H-bound pneumococci. NIH R01HL071233
Early complement factors in the immunocomplex generated during intestinal ischemia / reperfusion injury (134.65)
Authors: Lee Haekyung , Green Danielle J. , Lai Lawrence , Hou Joan , Liu David , Cheong Cheolho , Park Chae Gyu , Zhang Ming 
Published: January 2023

Abstract
One novel example of the innate autoimmunity occurs in ischemia/reperfusion (I/R) injury, in which reperfusion of ischemic tissues elicits an acute inflammatory response activated by natural IgM (nIgM) binding to ischemia-specific self antigen. To identify the immediate downstream pathway following nIgM-ischemic antigen interaction, we isolated the nIgM-ischemic antigen immunocomplexes from the local tissue of animals treated in intestinal I/R injury model, and examined the presence of initial molecules of three complement pathways. As expected, mannan-binding-lectin (MBL) was detected in the nIgM-ischemic Ag immunocomplex. In addition, C1q was also present on the immunocomplex. However, Factor B was not detected in the immunocomplex. To further examine the role of the alternative pathway in I/R injury, we employed Factor B knockout mice in the intestinal model. Our results showed that Factor B knockout mice were not protected from local tissue injury, and their complement system was activated by nIgM during I/R. These results indicated that the lectin pathway of complement operates immediate downstream of nIgM and ischemic antigen interaction during intestinal I/R. Furthermore, the classical pathway also involves the formation of nIgM-ischemic antigen immunocomplex. Finally, the alternative pathway of complement is not involved in I/R injury induction in the current intestinal model.
Receptor-independent, lipid dependent mechanism of Syk kinase activation in dendritic cells (134.71)
Authors: Ng Gilbert , Sharma Karan , Ward Sandra M , Desrosiers Melanie D , Stephens Leslie A , Schoel Michael , Li Tonglei , Lowell Clifford A , Ling Chang-Chun , Amrein Matthias W , Shi Yan 
Published: January 2023

Abstract
The binding of antigens to professional antigen-presenting cells (APCs), particularly dendritic cells (DCs), is essential for immune activation. Previously, it was shown that uric acid crystals, the causative agent of gout, were released from dying and injured cells as a "danger signal" to initiate a robust adaptive immune response. But how uric acid crystals lead to APC activation at a molecular level is unknown. Using atomic force microscopy (AFM) to analyze single cell activation in real time, we demonstrate that uric acid crystals directly bind cellular membranes, particularly cholesterol components, with very high affinity. Binding is dependent on intracellular Syk-kinase and PI3-kinase signaling and is independent of extracellular protein receptors. These findings suggest a mechanism that activates the immune system without specific cell surface protein receptors and presents a testable hypothesis for inflammation to materials without evolutionarily sensible receptors such as materials produced post-industrially. This research has applications in vaccine development, biomaterials, inflammation, and crystal-associated arthropathies.
The Mechanism of Invariant NKT Cell Responses to Viral Danger Signals (134.8)
Authors: Tyznik Aaron J , Tupin Emmanuel , Nagarajan Niranjana A , Her Min J , Benedict Chris A , Kronenberg Mitchell 
Published: January 2023

Abstract
Invariant (i)NKT cells influence the response to viral infections, although the mechanisms are poorly defined. Here we show that these innate-like lymphocytes secrete IFN-γ upon culture with CpG oligodeoxynucleotide-stimulated dendritic cells (DCs) from mouse bone marrow. This requires TLR9 signaling and IL-12 secretion by the activated DCs, but does not require CD1d expression. iNKT cells also produce IFN-γ in response to mouse CMV (MCMV) infection. Their mechanism of MCMV detection is quite similar to that of CpG, requiring bothTLR9 signaling and IL-12 secretion, while the need for CD1d expression is relatively minor. Consequently, iNKT cells have the ability to respond to a variety of microbes, including viruses, in an antigen-independent manner, suggesting they may play a broad role in anti-pathogen defenses despite their limited TCR repertoire.
Drosophila glycoprotein 93 is an ortholog of mammalian heat shock protein glycoprotein 96 and retains chaperone function for both Toll-like receptors and integrins (134.82)
Authors: Morales Crystal , Wu Shuang , Yang Yi , Hao Bing , Li Zihai 
Published: January 2023

Abstract
Mammalian heat shock protein (HSP) glycoprotein 96 (gp96) is an obligate chaperone for multiple integrins and Toll-like receptors (TLR). A database search revealed glycoprotein 93 (gp93) in Drosophila with high sequence homology to gp96, with unknown function. To determine if gp93 and gp96 are functionally conserved, we expressed gp93 in gp96 deficient mouse cells. We found that gp93 is able to chaperone multiple gp96 clients including α4, αL, β2 integrins and TLR2. Whereas gp96 undergoes intermolecular disulfide bond formation, gp93 is unable to do so due to absence of a critical cysteine residue at the N-terminus. However, site-directed mutagenesis of both gp96 and gp93 demonstrated that intermolecular disulfide bond formation is not critical for chaperone function. We conclude that gp93 is the Drosophila ortholog of gp96 and that its chaperone function is conserved. Further study of gp96 from an evolutionary angle should be informative to uncover the detailed mechanism of this understudied HSP90 paralogue in its chaperone function.
Z.L. is supported by NIH grant R01AI070603. C.M. is supported by a NIH predoctoral training grant 08-TA1007080F.
The use of ENU-mutagenesis mouse model to study the role of IL-15 alternative splice variant in the control of herpes simplex virus-1 infection (134.85)
Authors: Ku Chia-Chi , Yang Fu-Ju , Chang Pin-Fang , Wang Jy-Hsiu , Yeh Chao-Wei , Chang Mei-Ling , Kung John 
Published: January 2023

Abstract
Cytokine splice variants generated from alternative splicing of pre-mRNA have been broadly described and are implicated to influence cytokine signaling. Nonetheless, their importance in regulating the immune response remains unclear. The ENU-mutagenized pedigree 191 (P191) generated by the Mouse Mutagenesis Program Core Facility funded by the National Science Council was characterized by its depressed expression of CD44 on CD8 T cells. The mutant gene was linked to chromosome 8 and was mapped to IL-15 mRNA. Infection of P191 mutant mice with HSV-1 via flank skin revealed insufficient control of zosteriform as results of severe and delayed pathological manifestations, increased viral yields and lacking of Gr1+ cell recruitment to the lesional site. Whereas antigen specific CD8 T cells were generated in P191 mutant mice after HSV-1 infection detected with MHC class I tetramer in complex with HSV-1 gB498-505 epitope by flow cytometric analysis, the number was declined later time as opposed to be accumulated as generated in the wild type mice. These results have suggested that expression of IL-15 alternative splice variant could not only have effect ongenerating effective innate immune response in skin but also affect the function and maintenance of CD8 memory cells against HSV-1 infection. However, how the IL-15 splice variant modulates these immune mechanism remains to be clarified.
How caspase-7 controls intracellular infection in macrophages (134.86)
Authors: Amer Amal , Kanneganti Thirumala-Devi , Tridandapani Susheela , Wewers Mark 
Published: January 2023

Abstract
Legionella pneumophila (L. pneumophila), the causative agent of a severe form of pneumonia called Legionnaires' disease, replicates in human monocytes and macrophages. Most inbred mouse strains are restrictive to L. pneumophila infection except for the A/J, Ipaf-/- and caspase-1-/- derived macrophages. Particularly, caspase-1 activation is detected during L. pneumophila infection of murine macrophages while absent in human cells. Recent in vitro experiments demonstrate that caspase-7 is cleaved by caspase-1. However, the biological role for caspase-7 activation downstream of caspase-1 is not known. Furthermore, whether this reaction is pertinent to the apoptosis or to the inflammation pathway or whether it mediates a yet unidentified effect is unclear. Using the intracellular pathogen L. pneumophila, we show that upon infection of murine macrophages, caspase-7 was activated downstream of the Ipaf inflammasome and required caspase-1 activation. Such activation of caspase-7 was mediated by flagellin. Remarkably, mice lacking caspase-7 and their macrophages allowed substantial L. pneumophila replication. Permissiveness of caspase-7-/- macrophages to the intracellular pathogen was due to defective delivery of the organism to the lysosome and to delayed cell death during early stages of infection. These results reveal a new mechanism for caspase-7 activation downstream of the Ipaf inflammasome and present a novel biological role for caspase-7 in host defense against an intracellular bacterium.
The effects of HSP72 expression on adhesion receptor activation and phagolysosome function in human PMNs (134.93)
Authors: Osterburg Andrew R. , Schwemberger Sandy , Babcock George F 
Published: January 2023

Abstract
Heat shock protein 72 (HSP72) expression is a hallmark of functionally suppressed neutrophils from pediatric burn patients. CD11b and CD15 are critical receptors that mediate neutrophil (PMN) adhesion. In this study, we examined the effects of HSP72 on these receptors as well as phagolysosome function. Expression of CD11b, CD15 and pHrodo were measured by flow cytometry. HSP72 expression in PMNs, induced by 60-90 min incubation at 42C, suppressed the upregulation of high affinity CD11b conformation induced by fMLP (~90% reduction vs controls). Additionally, CD15 expression is reduced in HSP72 positive PMNs. GM-CSF treatment (5-25 ng/ml) appears to have a modest ability to preserve PMN function in stressed PMNs. HSP72 positive PMNs also have a reduced capacity phagocytose. Opsonized pHrodo labelled Staphylococcus aureus were incubated with HSP72 positive or negative PMNs. Control samples had significantly more pHrodo positive bacteria (~2-fold increase, controls vs stressed PMNs, P&lt;0.01) than the thermally stressed cells. However, the HSP72 positive PMNs appeared to acidify phagolysosomes to the same extent as control PMNs. Taken together, these data suggest that HSP72 expression reduces adhesion as well as the extent of phagocytosis. These deficits may contribute to the immune suppression found in thermally injured patients. Supported by Shriners of North America.
Induction of MyD88-Dependent Pro-inflammatory Cytokines Contributes to Lethal Toxicity of Staphylococcal Enterotoxins in Mice (135.13)
Authors: Saikh Kamal U , Kissner Teri L , Cisney Emily D , Ruthel Gordon , Ulrich Robert G 
Published: January 2023

Abstract
An elevated pro-inflammatory cytokine response is a primary cause of death by toxic shock after exposure to staphylococcal enterotoxin (SE). Identifying all host targets that control signaling for toxic shock is vital for developing a therapeutic strategy. We examined the role of the signaling adaptor MyD88 in cell culture and a mouse model of toxic shock. Our results indicated that elevated TNF-a, IFN-g, IL-1, and IL-6 production from mouse spleen cells treated with SEA alone, or in combination with lipopolysaccharide (LPS), was regulated by MyD88. Consistent with these results, MyD88-/- mice had impaired pro-inflammatory cytokine production in response to SEA and were resistant to a lethal SEA challenge. MyD88- dependent SEA- or SEB- induced lethality in mice was further confirmed in LPS- independent, D-galactosamine-sensitized mice. Our results demonstrate that MyD88-dependent pro-inflammatory signaling is responsible for SE toxicity. These findings offer important insight upon SE exposure and subsequent therapy targeting MyD88.
Downregulation of the TLR2-mediated signal by the DC-SIGN ligand Man-LAM (135.14)
Authors: Ohtani Makoto , Hasebe Akira , Iyori Mitsuhiro , Mohammad Haque Shamsul , Totsuka Yasunori , Shibata Ken-ichiro 
Published: January 2023

Abstract
C-type lectins have been shown to function both as adhesion and as pathogen recognition receptors. We have demonstrated that the Toll-like receptor 2 (TLR2) ligand FSL-1 enhanced phagocytosis of bacteria by enhancing expression level of scavenger receptors and C-type lectins such as DC-SIGN (dendritic cell-specific ICAM3 grabbing nonintegrin). This study demonstrated that the DC-SIGN ligand Man-LAM inhibits the TLR2-mediated signaling pathway and DC-SIGN forms a complex with TLR2 on the cell surface.
The role of IRF-1 on T cell subsets shift during pathogen infection (135.15)
Authors: Maruyama Saho , Kanoh Makoto , Matsumoto Akira , Asano Yoshihiro 
Published: January 2023

Abstract
[Purpose] Pathogen infection induces a shift to Th1 and inhibits a shift to Th2. The transcription factor IRF-1 is known to be essential for inducing IL-12 production and a shift to Th1. However, IRF-1 deficient cells express IL-12 p40 gene and induce Th1 cells during Listeria monocytogenes (Lm) infection. On the other hand, the effect of IRF-1 on Th2 is unknown. Since there is no inhibition of IL-4 production in the absence of IRF-1, we investigated the role of IRF-1 on IL-4 transcription during Lm infection.
[Results] (1) IL-4 production of cloned Th2 (MS-SB) cells was not inhibited by Lm infection of the clone. (2) When the mixture of MS-SB and T-depleted wild type or IRF-1 KO splenic cells were infected with Lm, Il-4 production was inhibited. Therefore, IRF-1 functions to inhibit IL-4 production in Th2 cells. (3) We transfected MS-SB cells with Luciferase reporter plasmid containing IL-4 promoter and IRF-1 expression plasmid. When MS-SB cells were stimulated with PMA plus Ionomycin, IL-4 production was inhibited without affecting Luciferase activity. Therefore, IRF-1 does not inhibit IL-4 promoter activity.
[Conclusion] There are two silencer regions in down stream of IL-4 coding region, and these silencers contain IRF-1 binding motif. Our results suggest that IRF-1 functions as a negative regulator for IL-4 gene transcription via silencer regions in Th2 cells during Lm infection.
TLR9 activation is an important mechanism of antigen-induced chronic lung inflammation (135.19)
Authors: Ito Toshihiro , Schaller Matthew , Hogaboam Cory M. , Lukacs Nicholas W. , Chensue Stephen W. , Kunkel Steven L. 
Published: January 2023

Abstract
It is likely that the continuous host response to a persistent challenge polarizes the cytokine environment toward a Th2 cytokine phenotype. We investigated the role of TLR9 in a Th2-driven pulmonary granulomatous response, initiated via the embolization of Schistosoma mansoni eggs to the lungs of mice. TLR9-/- mice showed an increase in pulmonary granuloma size, augmented collagen deposition, an increase in the Th2 cytokine phenotype, impaired accumulation of dendritic cells (DCs), and an increase in numbers of lung macrophages compared with WT mice. BM-derived DCs, but not macrophages, promoted the production of Th2 cytokines from CD4+ T cells during the S. mansoni egg antigen-induced immune response. In addition, DCs from TLR9-/- mice induced impaired Th1 cytokine (IFN-γ) and enhanced Th2 cytokine (IL-4, IL-5, and IL-13) compared with DCs from WT mice. Macrophages from TLR9-/- mice expressed significantly higher alternatively-activated (M2) phenotype characterized by increased "found in inflammatory zone-1" (FIZZ-1) expression. Passive immunization with neutralizing antibodies specific for FIZZ-1 during granuloma formation resulted in a decrease in granuloma size and collagen deposition. Together, these results suggest TLR9 plays an important role in the maintenance stage of specific chronic lung disorders.
This work was supported by NIH grants P01-HL031963, HL092845, HL074024, and HL031237.
Control of Interleukin-27 p28 Gene Transcription by Interferon Regulatory Factors (135.21)
Authors: Liu Jianguo 
Published: January 2023

Abstract
Interferon Regulatory Factor (IRF) family members, especially interferon regulatory factor-1 (IRF-1) and interferon regulatory factor-8 (IRF-8 or ICSBP), play important roles in interferon signaling in a wide range of host responses to infection and malignant growth. Interleukin-27 (IL-27), as a member of IL-12 family cytokines, not only acts like a pro-inflammatory cytokine that plays an important role in the regulation of differentiation of naive T helper cells but also possesses anti-inflammatory properties. IL-27 is consisted of Epstein-Barr virus (EBV)-induced gene 3 (EBI3), an IL-12p40-related protein, and p28, an IL-12p35-related polypeptide. Our recent work has revealed an intimate relationship between IRF-1 and IL-27 p28 in that IRF-1 regulates IL-27 p28 gene transcription by specifically binding to the IRF-1 response elements in the p28 promoter. In this study, we find that IRF-8 deficient macrophages are highly defective in the production of IL-27 at both mRNA and protein levels. Transcriptional analyses reveal that IRF-8 is a potent activator of the IL-27 p28 gene. It acts independent of the existing IRF-1 binding site located at -57 to -48 in the IL-27 p28 promoter. Consistent with this observation, over-expression of IRF-8 induces the IL-27 p28 promoter activity in a dose-dependent manner. This study provides further novel mechanistic information regarding how signals initiated during innate and adaptive immune responses synergize to yield greater IL-27 production and sustained cellular immunity.
Reprogramming of TLR4 pathways in endotoxin-tolerant cells (135.26)
Authors: Medvedev Andrei E , Chen Haiyan , Song Chang , Wahl Larry M , Fitzgerald Katherine A , Li Liwu , Piao Wenji 
Published: January 2023

Abstract
Endotoxin tolerance is important in the pathogenesis of the anti-inflammatory response syndrome and secondary infections in septic shock survivors. We elucidated whether reprogramming of TLR4 responses in endotoxin tolerance is mediated by altered signalosome assembly, kinase activation and up-regulation of negative regulators of TLR4 signaling. LPS stimulation of medium-pretreated human monocytes induced TAK1 activation, IRAK1-IKKγ association and TRAF6/IKKγ ubiquitination, while LPS tolerization diminished these responses. LPS-tolerant cells showed increased expression of Tollip, SOCS1, IRAKM, and SHIP1 that correlated with reduced expression of TNF-α, IL-6 and IL-8, while exhibiting similar levels of TNFRII, formyl peptide receptor I, PgE synthase and bactericidal/ permeability-increasing protein-like 2. Endotoxin tolerization suppressed LPS-mediated TLR4-TRIF-TBK1 associations, activation of TBK1 and IRF3, expression of RANTES and IFN-β, but increased levels of SIKE and SARM. Expression of Tollip in 293/TLR4/MD-2 cells blunted activation of NF-κB and RANTES in response to LPS. Thus, endotoxin tolerance interferes with LPS-inducible TAK1 activation, TLR4-TRIF-TBK1 and IRAK1-IKKγ assembly, TRAF6/IKKγ ubiquitination, TBK1/IRF3 activation and increases expression of negative regulators of TLR signaling (supported by AI067497 (KAF.), AI64414 (LL) and AI059524 (AEM)).