bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapamycin Induced Transactivation of EGFR: Implications in the Regulation of Cellular Apoptosis
Authors: Chaturvedi Deepti , Cohen Michael S. , Taunton Jack , Patel Tarun B. 
Published: June 2021

The mammalian target of rapamycin (mTOR) signaling network regulates cell growth, proliferation and cell survival. Deregulated activation of this pathway is a common event in diverse human diseases such as cardiac hypertrophy, vascular restenosis, nephrotic hypertrophy and cancers. Because of its anti‐proliferative properties, the mTOR inhibitor, rapamycin (a macrolide antibiotic), has been widely used in conjunction with coronary stents to prevent restenosis in coronary arteries following balloon angioplasty. However, in some cases mTOR inhibition by rapamycin does not attenuate the anti‐proliferative and apoptotic effects. Thus, we undertook a detailed study to elucidate the mechanism by which cells confer resistance to rapamycin. Our studies using primary rat aortic vascular smooth muscle cells (VSMC), mouse lung fibroblasts (B82L), COS7 cells, and primary mouse embryonic fibroblasts (PMEFs) show that rapamycin activates ERK1/2 signaling. Our data demonstrate that rapamycin‐mediated activation of the Erk1/2 signaling requires (a) the expression of the EGFR, (b) its tyrosine kinase activity, and (c) intact tyrosine auto‐phosphorylation sites on the receptor. Indeed, rapamycin causes tyrosine phosphorylation of the EGFR. This transactivation of EGFR requires activation of c‐Src, as Src kinase inhibitor (PP2), but not PP3, obliterates the ability of rapamycin to increase Erk1 or RSK1 phosphorylation. Rapamycin treatment also triggers activation of cell survival signaling pathway by activating the pro‐survival kinases Erk1/2 and p90RSK1. Given these findings we hypothesize that rapamycin‐ mediates transactivation of EGFR and activates the pro‐survival pathway via Src kinase.Supported by NIH grant GM 079226
Disruption of cyclin D3‐cdk4 complexes in the human diffuse large B‐cell lymphoma OCI‐LY18 results in caspase‐3‐dependent apoptosis
Authors: Gumina Maria R. , Chiles Thomas C. 
Published: June 2021

Normal human B lymphocytes express cyclins D1 and D3. By contrast, we have found that the human diffuse large B‐cell lymphoma (DLBCL), OCI‐LY18 (LY18) uniquely expresses cyclin D3. This non‐redundancy of D‐type cyclin expression suggests that inhibition of cyclin D3‐cdk4 complexes may represent a potential therapeutic target. To investigate the contribution of cyclin D3‐cdk4 complexes in LY18 cells, we treated cells with a chemical cdk4 inhibitor (Cdk4i) in order to selectively disrupt cyclin D3‐cdk4 complexes. We report herein that Cdk4i treatment of LY18 cells leads to G0/G1 phase arrest and apoptosis. Consistent with these findings, transduction of p16(INK4a) peptidyl mimetics (TAT‐p16) into LY18 cells led to disruption of cyclin D3‐cdk4 complexes and apoptosis. Depletion of cyclin D3‐cdk4 complexes resulted in decreased retinoblastoma protein phosphorylation on cdk4‐targeted S807/S811. In addition, we found that apoptosis was dependent on caspase‐3 activation. These findings suggest that cyclin D3‐cdk4 holoenzymes are required for LY18 cell survival. The results also suggest that targeting cyclin D3‐cdk4 complexes in human DLBCLs may prove to be an effective therapeutic strategy.This work was supported by USPHS grant AI60896 and AI49994.
CCR3 chemokine expression is increased by tumor necrosis factor‐alpha in neuroblastoma cells
Authors: Buels Kalmia S , Jacoby David B , Fryer Allison D 
Published: June 2021

Eosinophils cluster around parasympathetic nerves in asthmatic lungs and in antigen challenged animals where they mediate airway hyperreactivity. CCR3 receptors are found on eosinophils and blocking them with antagonists prevents airway hyperreactivity in antigen challenged guinea pigs. To determine what CCR3 chemokines are made by nerves during an inflammatory response, we treated human neuroblastoma cells (SK‐N‐SH) with a cytokine that is increased in asthma, tumor necrosis factor‐alpha (TNFγ; 3 to 3000 U/mL), for 24 h. We screened mRNA (by real‐time PCR) and soluble proteins (by ELISA) for known CCR3 chemokines including CCL5 (RANTES), CCL7 (MCP‐3), CCL8 (MCP‐2), CCL11 (eotaxin‐1), CCL13 (MCP‐4), CCL15 (MIP‐1d), CCL24 (eotaxin‐2), CCL26 (eotaxin‐3), and CCL28 (MEC). We found that SK‐N‐SH cells expressed mRNA for CCL5, CCL7, CCL8, and CCL11. TNFα increased mRNA expression for these same chemokines in a concentration dependent manner. TNFα also increased protein expression for three of these chemokines (CCL5, CCL7, and CCL11). Thus, neuroblastoma cells express a subset of CCR3 chemokines that can be increased by TNFα. These data suggest a mechanism whereby neurons can actively recruit eosinophils that can subsequently mediate neuronal hyperreactivity in asthma.Funded by: NIH: GM071338‐02, HL54659, HL55543, ES014601
CD4+ CD25+ Foxp3+ regulatory T cells induce cytokine deprivation apoptosis of the effector CD4+ T cells
Authors: Pandiyan Pushpa , Lenardo Michael 
Published: June 2021

A key question in mammalian immunology is how CD4+CD25+Foxp3+ regulatory T cells (Tregs) suppress immune responses. Here we show that Tregs induce apoptosis of effector CD4+ T cells in vitro and in a mouse inflammatory bowel disease (IBD) model without affecting their early activation or proliferation. They also induced Foxp3 expression in Tresps that resisted death in vitro. Common gamma chain cytokines reversed Treg‐induced apoptosis. Death required Bcl‐2 interacting mediator of cell death (BIM) and Akt1/Protein Kinase‐B induced dephosphorylation of the bcl‐2 antagonist of cell death (BAD) protein. Thus, cytokine deprivation induced apoptosis is a prominent event in Treg‐inhibition of T cell responses.This work was supported by the intramural research program of NIAID, NIH. P.P is supported by a National Academy of Sciences/National Research Council fellowship.
POLYMORPHISM OF THE HUMAN TNF PROMOTER REGION IN BRAZILIAN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS.
Authors: Pancoto João Alexandre Trés , Mendes Junior Celso T. , Lucisano‐Valim Yara M. , Dias‐Baruffi Marcelo , Donadi Eduardo A. 
Published: June 2021

INTRODUCTION: Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by multisystemic organ involvement, polyclonal B‐cell activation and the production of autoantibodies. Several family studies have shown convincing evidences of multiple genetic loci associated with SLE development. TNF is a potent proinflammatory cytokine that plays an important role in the pathogenesis of SLE, and certain alleles of the tumor necrosis factor (TNF) gene have been consistently associated with the disease, particularly the ‐308‐A/G functional promoter polymorphism. In the present study we analyzed the allelic distribution of TNF‐308A/G in Brazilian SLE patients.METHODS AND RESULTS: A total of 148 SLE patients and 130 matched healthy controls were typed for the TNF‐308A/G polymorphism by polymerase chain reaction using allele‐specific oligonucleotide primers. A significant increase of the TNF G/A 308 genotype was observed in SLE patients when compared with healthy controls (p < 0.0001; OR = 7.156; 95% I. C.: 3.462–14.792).CONCLUSIONS: Since the Brazilian population is highly genetically diverse, the results reported here are in agreement with those reported for other populations, and corroborate the role of TNF in disease pathogenesis and the TNF‐308A/G genotype, which has been associated with high production of TNF, as conferring susceptibility to the disease.RESEARCH SUPPORT: CAPES
IL13 Gene Variants Influence Early Life Weight Gain in Breastfed Male Infants
Authors: Lohman Carla , Stern Debra , Klimecki Walt , Vercelli Donata , Wright Ann , Halonen Marilyn 
Published: June 2021

Rationale: Although IL‐13 has been described mainly as an immune factor involved in Th‐2 related events, there are a few studies suggesting that this cytokine may have roles beyond this context. In the context of studies suggesting an involvement in mammary gland development, we hypothesized that IL13 gene variants might differentially affect growth of breastfed infants.Methods: Children were enrolled in the population based Tucson Infant Immune Study. Weight and type of infant feeding assessed prospectively from birth. Genotypes were determined with high‐throughput Taqman® assays for IL13 SNPs +2044 G/A (rs20541). Analyses were limited to breastfed non‐Hispanic White children. Non‐parametric tests were used to assess differences between groups.Results: Male breastfed infants homozygous for GG at +2044 were heavier than those with other alleles (homozygous or heterozygous for the A allele) in the first month of life (p=0.010). This IL13 gene variant did not influence birth weight. Calculating both weight gain and rate of weight gain also revealed significant increases for +2044 GG homozygote males (p=0.007 and 0.010, respectively). Female infants did not show these weight‐IL13 gene relations.Conclusion: IL13 genotypes appear to influence growth in early infancy among breastfed male but not female infants.Funded by: NIH grants AI 42268 AI 61811, HL66391
Combination of multiple genes from lupus and diabetes prone mice leads to a novel mouse model for lupus
Authors: Sim Davis Lok , Bagavant Harini , Ge Yan , Gaskin Felicia , Fu ShuMan , Deshmukh Umesh S 
Published: June 2021

The multigenic nature of systemic lupus erythematosus (SLE) is responsible for the varied serological and clinical manifestations observed in patients. Depending on the genotype, spontaneous mouse models of lupus only recapitulate certain features of the disease. This study was undertaken to test the hypothesis, that a mouse with a combination of most autoimmune genes would develop lupus similar to that seen in patients. For this purpose we crossed the lupus‐prone NZM2328 mice with the diabetes‐prone NOD mice and investigated the female F1 mice for autoimmunity.While the female F1 mice did not develop any diabetes, they developed severe proteinuria with >80% incidence by 10 months of age. Kidneys showed glomerular IgG and C3 deposits, with onset of acute proliferative GN between 3–5 months and chronic GN by 7 months of age. All F1 females developed ANA and anti‐dsDNA antibody. Also, sera from 70% of F1 mice immunoprecipitated the snRNP particle compared to only 20% NOD mice and 0% NZM2328 mice. The F1 mice showed elevated expression of type 1 interferon (IFN) inducible genes, in comparison to the NOD mice.Our study demonstrates that combination of multiple autoimmune genes from the NZM2328 and NOD mice results in a novel spontaneous mouse model for lupus nephritis. The disease phenotype in this model represents a large fraction of the human SLE patients.
Hierarchical requirement for CpG Motifs in dendritic cell activation induced by DNA‐containing immune‐complexes
Authors: Yasuda Kei , Uccellini Melissa B. , Richez Christophe , Viglianti Gregory A , Akira Shizuo , Marshak‐Rothstein Ann , Rifkin Ian R. 
Published: June 2021

In systemic lupus erythematosus (SLE), immune complexes (ICs) containing mammalian DNA activate dendritic cells (DC) at least in part through Toll‐like receptor 9 (TLR9). However, the DNA sequence required for this TLR9 activation is unclear because, unlike bacterial or viral DNA, mammalian DNA contains very few of the classical unmethylated CpG motifs believed to be important for TLR9 activation. To address this question, we treated mouse DC with immune complexes containing DNA fragments of defined sequence, including sequences obtained from CpG islands within the mammalian genome, and measured cytokine production and co‐stimulatory molecule upregulation. We found that although the strongest activation was elicited by classical unmethylated CpG motifs, effective activation was also elicited by methylated classical CpG motifs and by unmethylated non‐classical CpG motifs. The activation was entirely TLR9‐dependent. In contrast, no activation was elicited by DNA lacking CG sequences. Overall, the data indicate that IC containing DNA sequences found in mammalian DNA are able to activate DC, providing a possible explanation for how DNA‐containing IC might cause immune system activation in patients with SLE.This research is supported by a NIH (NIAMS) program project grant.
The receptor for complement anaphylatoxin C5a protects against the development of airway hyperresponsiveness in allergic asthma by inhibiting cysteinyl leukotriene pathway
Authors: Sinha Meenal , Drouin Scott , Wetsel Rick 
Published: June 2021

We have reported that complement component C5 is protective against airway inflammation in a rodent model of Aspergillus fumigatus induced allergic airway disease. Using mice deficient in the C5a receptor (C5aR) and an antagonist specific for the C5aR, we tested if these responses could be mediated by C5a, an activation‐induced cleavage fragment of C5. Consistent with previous results, C5aR−/− mice and wild‐type (WT) mice treated with a specific C5aR antagonist exhibited exacerbated airway hyperresponsiveness (AHR) compared to the WT mice. We also examined if Th2 responses, that are known to regulate many aspects of allergic airway inflammation including AHR, were elevated in the lungs of C5aR−/− mice as C5a and its receptor are thought to promote Th1 responses. Surprisingly, Th2‐type cytokines IL‐5 and IL‐13 were significantly reduced in the lungs and bronchoalveolar lavage fluid of C5aR−/− mice. However, pretreatment with a specific cysteinyl leukotriene (cysLT) receptor 1 antagonist could abolish AHR in C5aR−/− as well as in WT mice, suggesting that the absence of C5aR leads to increased cysLT signaling in the lung. These data demonstrate a previously unobserved dual role of the C5aR in allergic lung disease, i.e., protection against AHR mediated by cysLT pathway suppression, but elevation in Th2 cytokines.Supported by N. I. H. Grants AI025011 and HL074333 (to R.A.W.)
Role of Matrix‐metalloprotease‐7 in a Model of Experimental Asthma
Authors: Goswami Sangeeta , Barranco Wade , Greenlee Kendra J , Seryshev Alexander B , Corry David B , Kharadmand Farrah 
Published: June 2021

Bronchial asthma is a respiratory tract disease characterized by airway hyper‐responsiveness, mucus hyper‐production and inflammation. Airway epithelial cells are the initial sites where allergens are recognized. However, the role of epithelial cells in modulation of airway inflammation is not fully understood. One critical group of enzymes that regulate inflammatory processes in the lung is Matrix metalloproteases (MMP). We hypothesize that epithelial specific MMP7 modulates asthmatic phenotype by modifying inflammatory mediators produced by airway epithelium. We found that MMP7 null mice had reduced airway hyper‐reactivity in response to allergen challenge as well as fewer eosinophils in broncho‐alveolar lavage (BAL) fluid compared to WT mice. IL‐25 and Eotaxin, the critical mediators for asthma phenotype, were also reduced in MMP7−/− mice. Proteomic analysis of BAL fluid identified that Retinaldehydrogenase‐1 (RALDH‐1), a rate limiting epithelial specific enzyme for retinoic acid production, was up regulated in MMP7−/− asthmatic mice. In vivo inhibition of RALDH‐1, increased eotaxin protein expression in the airway and rescued the asthma phenotype in MMP7 −/− mice. Together, our data supports the role of MMP7 in modifying airway inflammation in asthma. We propose that identifying in vivo substrates for MMP7 may provide novel therapeutics for treatment of asthma.This work is funded by NIH grant (U19AI070973) to FK.
Interaction between Surfactant Protein‐A and Toll‐like Receptor‐4 in Lung
Authors: Awasthi Shanjana , Brown Kevin , Wolf Roman , White Gary 
Published: June 2021

Toll‐like receptors (TLR) and surfactant protein (SP)‐A, have been characterized as pathogen‐pattern recognition receptors. Both, TLR4 and SP‐A, have been found to interact in vitro, the in vivo evidence has been lacking. In this study, we investigated the binding between TLR4 and SP‐A in baboon lung by immunoprecipitation/immunoblotting and microwell‐based methods. Basal expression of total TLR4 and SP‐A proteins was quantified in fetal and adult baboon lung tissues by western immunoblotting and ELISA using TLR4 and SP‐A‐specific antibodies. We found that the TLR4 and SP‐A are co‐immunoprecipitated from baboon lung tissues. The binding between the two proteins was also confirmed under in vitro condition. Although the expression of TLR4 and SP‐A, alone, was found to be developmentally regulated, there was no significant difference in the co‐immunoprecipitated TLR4 and SP‐A proteins from fetal or adult baboon lung tissues as detected after immunoprecipitation/cross‐immunoblotting. The interaction between these pathogen‐recognition receptors may play a critical role in pulmonary innate immunity.Research Support: American Lung Association and Presbyterian Health Foundation.
Impaired Priming and Activation of the NADPH Oxidase in Patients with TLR Signaling Defects
Authors: Singh Anjali , Zarember Kol A , Jain Ashish K , Gallin John I 
Published: June 2021

The NADPH oxidase of neutrophils (PMN) plays a key role in host defense by producing reactive oxygen species (ROS). Here we examine the molecular basis of priming and activation of the NADPH oxidase in PMN from patients with two types of TLR signaling defects: interleukin‐1 receptor associated kinase‐4 deficiency (IRAK4) and NF‐kB essential modulator deficiency. (NEMO) We observed Impaired superoxide generation by LPS‐primed and fMLP‐activated IRAK4 PMN that correlated with inefficient translocation of cytosolic factors: p47phox, p67phox and Rac2 and the flavo‐cytochrome subunit: gp91phox to the membrane. While IRAK4 PMN produced ≤ 5% of normal ROS levels, NEMO PMN displayed ~50% of normal ROS with normal translocation of regulatory subunits. Compared to LPS‐primed normal PMN, p47phox phosphorylation was significantly lower in IRAK4 PMN. We further observed the down‐modulation of p47phox phosphorylation and membrane translocation by phosphatidylinositol 3‐kinase (PI3K) inhibitor LY2940002 in LPS‐primed normal PMN. In addition the phosphorylated levels of signaling kinases p21‐activated kinase (Paks) (IRAK4 deficiency) and p38 (IRAK4 and NEMO deficiency) were significantly lower in PMN of TLR signaling defects. We, hereby, reveal the role of defective p38‐ PI3K‐ Rac‐Paks signaling pathway in IRAK4 deficiency patient in impairing the NADPH oxidase mediated ROS generation.Research support: NIH, NIAID
Dendritic cells and natural killer dendritic cells are influenced by stress from thermal injury
Authors: Kawasaki Takashi , Kobayashi Makiko , Herndon David N , Suzuki Fujio 
Published: June 2021

We have previously reported that mice with partial‐thickness burn injuries (PT‐burned mice) are resistant to burn wound infections, while mice with full‐thickness burn injuries (FT‐burned mice) are susceptible. Recently, the contributions of dendritic cells (DC) and natural killer dendritic cells (NKDC: a novel subset of DC with NK cell properties) on host antibacterial innate immunities have been described. Therefore, in this study, the influence of stress from thermal injury on the DC properties and NKDC appearance was examined in 2 different murine models of thermal injuries.PT‐burned mice (mice with 1 to 2nd degree, 25% TBSA scald burn) and FT‐burned mice (mice with 3rd degree, 25% TBSA flame burn) were prepared as described previously. DC were prepared from spleens of mice 1, 3, 5, 7 and 14 days after burn injury. These cells (1×106 cells/ml) were cultured for 24 hrs with LPS or SAC. Cultured fluids harvested were assayed for CCL2, CCL3, IL‐10 and IL‐12 by ELISA. For NKDC, DC were analyzed for CD11c and DX5 expressions by flow cytometry.In the results, CCL3‐ and IL‐12‐producing DC were demonstrated in spleens of PT‐burned mice 3 to 5 days after the injury. In contrast, CCL2‐ and IL‐10‐producing DC were obtained from spleens of FT‐burned mice. Also, as compared with DC from normal mice, the marker of NKDC was increased 75% in DC from PT‐burned mice, while these cells in the DC preparation from FT‐burned mice decreased 65%.These results suggest that NKDC, as well as DC, may play a role on the antibacterial resistance of thermally injured hosts. (Supported by SHC NA #8610.)
Estrogen induces the expression of estrogen receptor in human macrophages
Authors: Jensen Amy L , Pioli Patricia A 
Published: June 2021

Monocytes and macrophages (Mφs) are exposed to fluctuations in estradiol (E2) during the menstrual cycle. In some cell types E2 has been shown to regulate expression of its own receptor (ER). E2 levels peak pre‐ovulation and during pregnancy when regulation of immune responses is needed to ensure reproductive success. We hypothesized that E2 up‐regulates ER expression to increase sensitivity to E2 and subsequently influence E2‐regulated inflammatory responses. As human monocytes and Mφs express both isoforms of the ER, ERα and ERβ, we determined whether E2 influences ER expression in these cells. We found no gender difference in mRNA or protein levels in monocytes and MØs. E2 treatment augmented ERα mRNA and protein expression in female Mφs and this was at least in part mediated transcriptionally. Intriguingly, E2 had no effect on monocyte ERα mRNA and protein levels. Up‐regulation of ERα during monocyte‐to‐Mφ differentiation correlated with an increased inhibitory effect of E2 on LPS‐induced IL‐8 production. These data show that ERα is differentially expressed and regulated in human monocytes and Mφs, and E2 acts as a positive regulator of ERα in Mφs. Importantly, ERα expression correlates with the ability of E2 to influence Mφ activation. This may be important when E2 levels are high and tolerance of sperm and an allogeneic fetus are imperative.Supported by NIH AI51877 and NIH T32AR007576 (to ALJ)
Increased NK‐DC co‐operation and resulting adaptive immune response after HSV infection involves TLR signaling
Authors: Woolard Stacie Necole , Nandakumar Subhadra , Kurt‐Jones Evelyn , Kumaraguru Uday 
Published: June 2021

The induction of DC maturation by TLR ligands is considered as a pivotal link between innate and adaptive immune responses. This renders the DCs capable of directing the T cell response. NK cells also express some of the TLRs expressed by DCs. It is our hypothesis that HSV orchestrates the early event of NK cell and DC interaction through TLR mediated signaling.To test this, we used autologous DCs that were stimulated with various TLR ligands described to be associated with HSV infection (TLR 2, 3, and 9) or cytokines or virus. NK cells (generated from NK precursors or isolated from lymphoid organs) were co‐cultured for 18 hours in the presence or absence of these DCs and later analyzed for their phenotypic changes (CD25, CD69, Chemokine receptors CCR7 and CxCR3), cytokine production (IFN‐γ), and cytotoxicity (YAC cells). NK cells’ acquired cytolytic ability was also tested against Daudi target cells which are usually resistant to NK killing. DCs and NK cells generated from bone marrows of MyD88 knockout were used similarly and in mix and match combination.The DCs were analyzed for upregulation of activation and co‐stimulatory markers (CD80, CD86, MHC class I and II, CD40 etc.). They were also analyzed for their stimulatory activity after osmatically loading of ova protein or HSV gB protein and measuring their ability to induce activation and proliferation of peptide specific T cells.The results suggest that the initial interaction between the DCs and NK cells are largely due to signaling through the TLR. If the cells lacked MyD88 signaling their productive interaction was greatly diminished.Acknowledgement: ETSU startup funds to U. Kumaraguru