bluuebunny/crossref_metadata_2025_split huggingface dataset:
SMOKING INHIBITS EXPRESSION OF PROINFLAMMATORY CYTOKINES AND ACTIVATION OF IRAK-1, p38 AND NF-κB IN ALVEOLAR MACROPHAGES STIMULATED WITH TLR2 AND TLR4 AGONISTS (40.6)
Authors: Chen Haiyan , Cowan Mark J , Hasday Jeffrey D , Vogel Stefanie N , Medvedev Andrei E 
Published: January 2023

Abstract
Bronchiolitis is common in smokers and we hypothesized that this may be due to impaired sensing of bacterial components via TLR2 and TLR4 by smokers’ alveolar macrophages (AM). AM and PBMC obtained from smokers and non-smoking volunteers were stimulated with TLR2 and TLR4 agonists, Pam3Cys and LPS, and expression of cytokines and activation of intracellular intermediates were examined. Smokers’ AM exhibited suppressed gene expression and secretion of pro-inflammatory cytokines TNF-α, IL-1β, IL-6, IFN-γ and chemokines IL-8 and RANTES upon stimulation with LPS and Pam3Cys, whereas expression of anti-inflammatory cytokines IL-10 and IL-1RA was not affected. Comparable expression levels of these cytokines and chemokines were detected in PBMC obtained from smokers and non-smokers, indicating that the suppressive effect of smoking is restricted to the lung. TLR2/4-inducible phosphorylation of IRAK-1 and p38, and IκB-α degradation were markedly inhibited in smokers’ AM, whereas expression levels of TLR2, TLR4, CD14, MD-2 mRNA, and TLR4 protein, were not significantly changed. These results indicate that smoking induces a state of tolerance in AM manifested by suppression of TLR2/4-induced signaling that may underlie bronchiolitis associated with smoking.
This work was supported by grants from Philip Morris USA Inc. and Philip Morris International, OTRD/University of Maryland, Baltimore, and NIH grants AI059524 (AEM) and AI44936 (SNV).
Epithelial cells trigger frontline immunoglobulin class switching through an SLPI-regulated pathway (41.7)
Authors: Xu Weifeng , He Bing , Chiu April , Chadburn Amy , Shan Meimei , Buldys Malwina , Ding Aihao , Knowles Daniel M , Santini Paul A , Cerutti Andrea 
Published: January 2023

Abstract
Epithelial cells (ECs) recruit B cells expressing class-switched IgG and IgA into mucosal effector sites and transport IgG and IgA antibodies across mucous membranes. Whether ECs initiate IgG and IgA class switching remains unknown. We found that ECs lining tonsillar crypts formed pockets populated by B cells expressing activation-induced cytidine deaminase (AID), a DNA-editing enzyme associated with ongoing class switch DNA recombination (CSR). ECs released AID- and CSR-inducing factors, such as B cell-activating factor of the TNF family (BAFF), after sensing microbial products through Toll-like receptors (TLRs). EC-induced IgG and IgA CSR was further amplified by thymic stromal lymphopoietin (TSLP), an epithelial IL-7-like cytokine that enhanced BAFF production by dendritic cells. Conversely, EC-induced IgG and IgA CSR was restrained by secretory leukocyte protease inhibitor (SLPI), an epithelial homeostatic protein that inhibited BAFF signaling in B cells. Our findings indicate that ECs function as mucosal guardians that orchestrate frontline IgG and IgA class switching through a TLR-inducible SLPI-regulated signaling program.
This work was supported by NIH grants AI057653 (to A.C.) and by NIH T32 training grant AI07621 (to W. X.).
Activation of NKT cells by a-Galactosylceramide treatment licenses lamina propria dendritic cells to abrogate the oral tolerance (42.10)
Authors: kang Chang-Yuil , Chang Jae-Hoon , Lee Jung-Mi , Yoon Hyun-Jun , Lee Kyoo-A , Chung Yeonseok 
Published: January 2023

Abstract
Dendritic cells (DC) play critical roles in Ag presentation and induction of immunity or tolerance. In previous our study, treatment of agonistic anti-CD40 mAb at that time of oral OVA did not abolish the oral tolerance induction whereas injection of α-galactosylceramide (αGC) blocked the oral tolerance. We demonstrate that treatment of αGC but not anti-CD40 mAb resulted in the full maturation of DC in lamina propria of small intestine (SI-LP) at early time window. This phenomenon caused by activated NKT cells which reside in SI-LP. DC in SI-LP (sLP-DC) from αGC-treated mice exhibited a stronger stimulator against allogeneic T cells than those cells from anti-CD40 mAb-treated mice. Ag presentation capability was also increased in sLP-DC by αGC. Importantly, maturated sLP-DC by αGC induced to differentiate of naïve CD4+ T cells into Th1- and Th2 cells toward intestinal OVA. In contrast, sLP-DC by anti-CD40 mAb treatment failed to generate Th differentiation but were involved in the generation of more numbers of Foxp3+ CD4+ T cells than those from αGC-treated group. On the other hand, the fact that recognition of intestinal Ag of naïve CD4+ T cells occurs in MLN, indicating MLN are privileged in triggering the interactions of sLP-DC and CD4+ T cells. Taken together, systemic treatment of αGC resulted in maturation of sLP-DC by NKT cells in the SI-LP and licensed DC educate CD4+ T cells in MLN, which can abrogate oral tolerance.
Polymorphisms in Paan-AG promoter influences NF-κB binding and transcription activity in HEK293 cells (42.12)
Authors: Langat Daudi K , Morales Pedro J , Omwandho Charles O , Fazleabas Asgerally T , Hunt Joan S 
Published: January 2023

Abstract
HLA-G is a protein highly expressed at the human maternal-fetal interface during pregnancy. It is thought to be critical for the survival of the semi-allogenic fetus. The baboon (Papio anubis) expresses an HLA-G-like protein termed Paan-AG in the placenta, and may serve as a model for HLA-G studies. Paan-AG shares many characteristics with HLA-G, including alternative splicing of the mRNA and restricted tissue expression of the protein. Our hypothesis is that the two genes share similar regulatory mechanisms. The objective of the current study was to assess binding of the transcription factor NF-κB to Paan-AG κB elements and determine the effects of binding on Paan-AG promoter activity. We assessed two Paan-AG alleles each containing two κB elements, κB1 and κB2. NF-κB bound both κB1 and κB2 elements in the AG1 allele. In contrast, only κB1 of the AG-2 allele bound to NF-κB; κB2 did not bind. Mutagenesis studies showed that the difference in binding was due to two nucleotide differences in the 3′ end of κB1. The functional activity of the two alleles also differed; AG2 consistently showed higher luciferase activity compared to AG1. Mutating the last two nucleotides in the 3′ end of κB1 resulted in an increase of luciferase activity to levels comparable to that of AG2. Overall, these results suggest that variations in the proximal promoter may influence transcription rates of Paan-AG as reported recently for HLA-G, and provide further evidence of the potential usefulness of the baboon as a model for in vivo HLA-G studies.
Supported by NIH grant HD39878 (JSH).
Immunomodulation of activated immune cells in experimental autoimmune encephalomyelitis (EAE) (42.7)
Authors: Song Fei , Gienapp Ingrid , Shawler Todd , Whitacre Caroline C. 
Published: January 2023

Abstract
The relapse rate is profoundly decreased in female multiple sclerosis (MS) patients during pregnancy. We previously reported that experimental autoimmune encephalomyelitis (EAE), an animal model of MS, is markedly suppressed when disease is induced during late pregnancy. Disease induction during the post partum period is enhanced. In this study, we assess the effects of pregnancy on activated T cells by transferring neuroantigen activated transgenic T cells into pregnant syngeneic wild type recipients (B10.PL). Myelin basic protein (MBP) TCR transgenic (Tg) donor splenocytes are activated in vitro with MBP NAc1-11 for 96 hours. These CD4+CD25+Foxp3- donor cells elicited a strong proliferative response and an increase in Th1 cytokines. The activated T cells were transferred i.v. into pregnant recipients and non-pregnant controls. Control mice showed acute and relapsing EAE, while pregnant recipients showed significantly reduced cumulative disease scores. Furthermore, pregnancy inhibited T cell proliferation and increased the number of B cells post transfer. The role of regulatory/suppressive T cells and inhibitory molecules on antigen presenting cells (B cells and DCs) are under study for their involvement in pregnancy suppression of EAE
(Supported by NIH grant AI 43376).
The role of liver NKT cells in the regulation of peripheral immune responses (42.9)
Authors: Li Wei , Duthie Malcom , Wang Weigang , Carper Katie , Kahn Stuart , Latchman Yvette , Reyes Jorge , Perkins James 
Published: January 2023

Abstract
We have previously shown that the liver plays an important role in oral tolerance induction. The liver can transfer tolerance to OVA from OVA fed mice to naïve mice. In this study we employed an oral tolerance model by OVA feeding to further explore the mechanisms underlying the role of the liver in oral tolerance induction. OVA feeding, either high dose or low dose, expanded NKT cells in the liver which expressed higher levels of CD95L and PD-L1, a moderate level of PD-1 on the surface, peaked at the 2nd dose feeding in the high dose group and at the 3rd dose feeding in the low dose group. The Foxp3+CD4+CD25+ T regulatory cells (Treg) showed a slight increase in the livers and spleens in the low-fed group, but increased only in the livers in the high-fed group. OVA feeding inhibited NKT cell linked T cell proliferation in both low and high dose fed livers and spleens. Elispot assay revealed an increase in IL-4 and IFN-γ production in the low-fed mice, but increased IL-10 in the high-fed mice. Moreover, the DTH responses to OVA stimulation were increased markedly in the NKT−/− mice with high dose feeding, but showed no significant change in the PD-L1−/− mice compared to that in WT mice. Our results indicate that the liver NKT cells are important in OVA-induced oral tolerance, particularly in high dose feeding. The function of NKT cell appears to depend on CD95L and CD4+CD25+Treg, but not on the PD-1/PD-L1 pathway. IL-10 appears dominant in high dose feeding, while IL-4 and IFN-γ show importance in low dose feeding.
Dendritic cell derived exosomes express a Streptococcus pneumoniae capsular polysaccharide type 14 cross-reactive antigen that induces protective immunoglobulin responses against pneumococcal infection in mice (43.10)
Authors: Colino Jesus , Snapper Clifford 
Published: January 2023

Abstract
Exosomes activate T cells in vivo, but whether exosomes are able to induce humoral immune responses is still unknown. We found that dendritic cells, but not other immune cells, constitutively release an exosome-associated glycoconjugate that is cross-reactive with the capsular polysaccharide of Streptococcus pneumoniae type 14 (Cps14-CRA). Cps14-CRA was localized to the cholesterol-enriched microdomains or rafts of the exosomes and was mapped to the β 1→6 branched N-acetyl-lactosamine derivatives of the Cps14-CRA. Injection of CFA primed naïve mice with purified DC exosomes induced Ig anti-Cps14 responses composed predominantly of IgM, IgG3 and IgG1. These responses were associated with protection against a lethal challenge with live S. pneumoniae type 14, but not with type 3 bacteria, and was correlated with the titer of elicited IgM and IgG3 anti-Cps14. These data show for the first time, that exosomes can induce a humoral immune response to an associated unprocessed, autologous antigen. Although anti-Cps14 Ig responses are specifically demonstrated, these could reflect a broader mechanism that modulates both natural immunity and autoimmunity to other glycotopes.
Transcriptional response of human dendritic cells to Borrelia garinii –defective CD38 and CCR7 expression detected (43.18)
Authors: Hartiala Pauliina , Hytönen Jukka , Pelkonen Jenni , Kimppa Katja , West Anne , Suhonen Juha , Lahesmaa Riitta , Viljanen Matti K 
Published: January 2023

Abstract
Lyme borreliosis is a tick-borne disease that can affect several organs and cause a variety of symptoms. In some patients, the infection may become chronic even after antibiotic therapy and cause persisting damage. Dendritic cells (DC) are involved in the initiation of both innate and adaptive immune responses. To study interactions between Borrelia garinii (Bg), one of the causative agents of Lyme borreliosis, and human dendritic cells, we used a cDNA microarray to compare the Bg induced DC transcriptional response to responses induced by lipopolysaccharide (LPS). The Bg induced response consisted of a smaller number of genes than the LPS induced response.
The microarray showed that the ectoenzyme CD38, which has an important role in DC chemotaxis and migration to lymph nodes, was strongly up-regulated by LPS but practically not at all by Bg. This finding was confirmed with quantitative RT-PCR and with flow cytometry at protein level. In addition, RT-PCR showed that the expression of the dominant mediator of DC migration, CCR7, was 11-fold greater in LPS stimulated than in Bg stimulated cells. These findings suggest that Bg may affect crucial DC functions by blocking the up-regulation of important molecules in DC migration, thus affecting further immune responses in Lyme borreliosis infection.
This study was supported by the Academy of Finland (Microbes and Man project)
Mycobacteria Induce Protective Effector Functions in a Subset of Nonprotective Phosphoantigen-reactive γ9δ2 T cells (43.21)
Authors: Spencer Charles T , Abate Getahun , Blazevic Azra , Hoft Daniel F 
Published: January 2023

Abstract
Human γ9δ2 T cells expand and produce protective cytokine and cytolytic responses during mycobacterial infection. γ9δ2 T cells are also stimulated by nonpeptidic phosphoantigens (i.e-IPP, HMB-PP), expressed by intracellular mycobacteria and infected cells. Therefore, purified phosphoantigens could be useful components of new vaccines or immunotherapeutics by stimulating protective γ9δ2 T cells. However, it is unclear whether γ9δ2 T cells induced by phosphoantigens can protect against mycobacterial replication. We show that while BCG-expanded γ9δ2 T cells potently inhibit intracellular mycobacterial growth, IPP/HMB-PP-expanded γ9δ2 T cells fail to inhibit intracellular mycobacteria, although both lyse Daudi targets. TLR co-stimulation during IPP expansion also failed to induce anti-mycobacterial γ9δ2 T cells. TCR spectratyping and CDR3 sequencing demonstrated that BCG-expanded γ9δ2 T cells expressed significantly less TCR sequence diversity than IPP-expanded γ9δ2 T cells. BCG-expanded γ9δ2 T cells respond similarly to BCG- and IPP-stimulation, while IPP-expanded γ9δ2 T cells responded poorly to BCG. BCG appears to stimulate an antigen-specific focusing event in γ9δ2 T cells while IPP acts like a mitogen with broad γ9δ2 T cell reactivity. The antigens and/or co-stimulatory signals required to induce protective γ9δ2 T cells remain to be identified.
Support: NIH R01-AI-48391, VTEU NO1-AI-25464
Early response of alveolar macrophages to Respiratory Syncytial Virus infection (43.23)
Authors: You Dahui , Ripple Michael , Simms Tiffany , Cormier Stephania 
Published: January 2023

Abstract
Respiratory syncytial virus (RSV) infection is the most common cause of lower respiratory tract infection in infants and elderly adults. Previous studies in humans and in animal models suggest that early infection with RSV may predispose to the development of asthma. However, the molecular mechanisms by which RSV induces changes in the immuno-environment of the airway are still largely unknown. The purpose of the present research was to identify the molecular effectors involved in the host response to RSV infection in alveolar macrophages (AMs). Seven day old mice were infected with RSV (4 x 104 TCID50/g body weight). Total RNA was isolated from airway AMs 5 hours post-infection and processed to perform expression analysis using the Affymetrix GeneChip (Mouse Genome 430 2.0s). A total of 424 genes were observed to be differently expressed. Of these, 187 genes were found to be up-regulated and 237 genes to be down-regulated. Many of these genes take part in cell signaling pathways including the IL-6 and p38 MAPK pathways. Interestingly, 10 genes were found to be involved in apoptosis. RSV infection resulted in complex and immediate cellular responses in AMs. Preliminary data suggests that RSV inhibits apoptosis of AMs. IL-6, amphiregulin and matrix metalloproteinase-13 may play roles in the subsequent development of asthma.
This publication was made possible by NIH grant number P20 RR020159 from the LSU/Tulane COBRE-CEIDR Program of the National Center for Research Resources. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of NIH.
Preexisting frequency of antigen-specific naive T cell dictates immunodominance of antigen-specific CD8+ T cells (43.25)
Authors: Kuroda Marcelo , Hasegawa Atsuhiko , Liu Huining , Vinet Heather C. , Subbramanian Ramu A. 
Published: January 2023

Abstract
Immunodominance is a common feature of Ag-specific CTL responses to infection or vaccines. Understanding the basis of immunodominance is crucial to understanding cellular immunity and viral evasion mechanisms and will provide a rational approach for improving vaccine design. This study was performed comparing CTLs specific for the SIV Gag p11C (dominant) and SIV Pol p68A (subdominant) epitopes that are consistently generated in Mamu-A*01+ rhesus monkeys exposed to SIV proteins. Additionally, vaccinated monkeys were used to prevent any issues of antigenic variation or dynamic changes in CTL responses by continuous Ag exposure. Analysis of the TCR repertoire revealed the usage of higher numbers of TCR clones by the dominant p11C-specific CTL population. Preferential usage of specific TCRs and the in vitro functional TCR-α and -β chain-pairing assay suggests that every peptide/MHC complex may only be recognized by a limited number of unique combinations of α and β chain pairs. The wider array of TCR clones used by the dominant p11C-specific CTL population might be explained by the higher probability of generating those specific TCR chain pairs. Our data suggest that Ag-specific naïve T cell precursor frequency may be predetermined and that this dictates immunodominance of CD8+ T cell responses. These findings will aid in understanding immunodominance and designing new approaches to modulate CTL responses.
B cell expression of TLR2 is critical for optimal induction of humoral immunity to intact Streptococcus pneumoniae (43.27)
Authors: Vasilevsky Sam , Sen Goutam , Chattopadhyay Gouri , Snapper Clifford M. 
Published: January 2023

Abstract
TLR2−/− mice immunized with Streptococcus pneumoniae (Pn) have defective type 1 (IgG3, IgG2b, and IgG2a) humoral immunity, but a similar type 2 (IgG1) response relative to WT mice. Of note, this defect in adaptive immunity was associated with a largely normal innate immune response to Pn. We thus hypothesized that TLR2 plays a critical role directly at the level of the adaptive immune system. We demonstrate that CD4+ T cells from Pn-primed TLR2−/− mice elicit a normal cytokine response after in vitro re-stimulation with Pn protein. In contrast, MyD88−/− mice, exhibiting both defective innate and type 1, but elevated type 2, humoral immunity to Pn, elicit an increased type 2 cytokine response. Bone marrow dendritic cells (BMDC) from TLR2−/− mice have only a modest defect in cytokine secretion, including IL-12, and undergo normal maturation in response to Pn. TLR2−/− BMDC pulsed with Pn and transferred into WT mice elicit a normal Ig response, relative to WT BMDC. In contrast, Pn fails to costimulate in vitro proliferation of purified TLR2−/− B cells activated via multivalent B cell receptor crosslinking, while costimulating WT B cells. Adoptive transfer studies demonstrate that TLR2−/−, but not WT, B cells are defective in eliciting Ig responses to Pn in either a TLR2−/− or WT background. These data are the first to indicate a critical role for B cell expression of TLR2 during a humoral immune response to an intact bacterium.
N.I.H. R01 AI49192
CD4 T cell memory of prior influenza infections regulate new CD4 and CD8 T cell responses (43.3)
Authors: Jelley-Gibbs Dawn M , McKinstry Kai , Strutt Tara , Dibble John , Swain Susan 
Published: January 2023

Abstract
Acute infections are often characterized by short-lived antigen presentation, but influenza infection results in long-lived antigen depots capable of stimulating CD4 and CD8 T cells long after live virus clearance. FACS purification of antigen presenting cells from mice at various times after flu infection, followed by co-culture with naive flu-specific T cells, has demonstrated that dendritic cells are the perpetrators of long-lived flu antigen presentation. However, there may be a reservoir of intact virus that persists at low levels in other cell populations. Regardless of the mechanism of antigen retention, access to long-lived flu antigen presentation is important for the generation of flu-specific memory T cells. Manipulations of our model system that result in enhanced circulation of effector T cells in the periphery of flu infected mice lead to impressive increases in memory T cell generation. Specifically, introduction of flu-experienced memory CD4 T cells during new CD4 and CD8 T cell priming, as well as induction of physical redistribution of newly primed effectors, results in greater effector circulation in peripheral sites and increased numbers of memory T cells. We propose that recirculation of effector T cells during flu infection allows for greater access to long-lived antigen depots, and consequently results in higher numbers of memory T cells.
Funding provided by NIH grant AI46530.
Helminthic infection enhances susceptibility to tuberculosis in a murine coinfection model (43.31)
Authors: Potian Julius Andrew , Bhatt Kamlesh , Liu Zhugong , Gause William , Salgame Padmini 
Published: January 2023

Abstract
Regions of the world with high incidence of Tuberculosis (TB) are also endemic for helminthic diseases. Helminthic infection elicits a profound Th2 immune response, which may alter theTh1 response necessary for the protection to TB. The impactof Th2 responses on the protective immune response elicited to TB is poorly understood. We co-infected BALB/c mice with the nematode Nippostrongylus brasiliensis (Nb) followed by virulent Erdman strain of Mtb via aerosolization. At 4 and 7 weeks post-Mtb infection, co-infected mice displayed significantly higher bacterial burden compared to mice infected with Mtb alone. Furthermore, the enhanced disease progression was accompanied by a shift in the Mtb-induced Th1 response to a Th2 response in the co-infected mice as demonstrated by an increase in Th2 cytokines IL-4 and IL-10. Taken together, theseresults demonstrate that helminth infection alters the ability of the host to mount an effective immune response to TB and modulates the course of tuberculosis disease. Clinically, elucidating the mechanisms which underlie alteration of immunity to TB will facilitate in the better design of TB vaccines and therapies.