bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protective immunity against invasive Streptococcus pneumoniae infections by tissue-specific memory Th17 cells (P4266)
Authors: Wang Yan , Jiang Bin , Weiser Jeffrey , Shen Hao 
Published: January 2023

Abstract
Pneumonia caused by Streptococcus pneumoniae (Sp) remains a leading cause of serious illness and death worldwide. Current vaccine is highly effective in preventing colonization by inducing serotype-specific antibodies. However, there is an increasing prevalence of infection by serotype strains not included in the vaccine; this highlights the need for a universal vaccine that protects against all serotypes. The first step in developing a universal vaccine is to elucidate the immune mechanism that can provide broad protection against different serotype Sp strains. We found that intranasal immunization of mice with Sp resulted in a strong CD4+T cell response in the lung that consisted of mostly Th17 cells but also IFNγ producing Th1 cells. These immunized mice were protected against lethal challenge with a different serotype strain of Sp and cleared bacteria in lung by day 2 post-challenge. Adoptive transfer of T cells from immunized mice also provided protection against a heterologous challenge, with a dominant Th17 recall response in the lung from donor memory T cells. Furthermore, immunization of mice with Listeria monocytogenes (LM) provided protection against a recombinant Sp strain expressing a CD4 epitope from LM (LLO190), as shown by decreased CFU in the lung, and elevated LLO190-specific Th17 response. Our results suggest that memory Th17 cells may play a key role in providing broad protective immunity against invasive Sp infection in a serotype independent manner.
Susceptibility of NOD/scid IL-2Rγnull mice inoculated with alcoholic patient white blood cells to Pseudomonas aeruginosa infection (P3029)
Authors: Nakamura Kiwamu , Asai Akira , Ohama Hideko , Tsuchimoto Yusuke , Tsuda Yasuhiro , Higuchi Kazuhide , Kobayashi Makiko , Suzuki Fujio 
Published: January 2023

Abstract
We have previously demonstrated that CCL2+ neutrophils (PMN-II) and IL-12−IL-10+ monocytes (M2 monocytes) are predominated in WBC of alcoholic patients. Since these cells are inhibitory on the generation of major antibacterial effector cells, in this study, we investigated the susceptibility of alcoholic patients to P. aeruginosa infections in a humanized murine model. To create an experimental model of alcoholic patients, 5 x 106 cells of WBC of alcoholic patients were adoptively transferred to X-irradiated-NOD/scid IL-2Rγnull mice. As a control, these mice were inoculated with healthy donor WBC. Then, they were infected s.c. with P. aeruginosa (10 CFU/chimera) and bacteria in liver and kidneys of these chimeras were quantified. In the results, bacteria grew (&gt; 103 CFU/g organ, 24 hrs after infection) in liver and kidneys of the chimeras created with alcoholic patient WBC, while bacteria disappeared within 24 hrs after P. aeruginosa infection from these organs of the control chimeras. CD14+ cells isolated from WBC of alcoholic patients were shown to be IL-10+IL-12−CCL1+ cells, while IL-10−IL-12+CCL1- cells were isolated from healthy donor WBC stimulated with heat-killed P. aeruginosa. These results indicate that chimeras created with alcoholic patient WBC are carriers of M2b monocytes and susceptible to P. aeruginosa infection, while chimeras created with healthy donor WBC are carriers of M1MΦ and resistant against these infections.
HLA-G 14bp polymorphism on HIV-1 perinatal transmission (P3041)
Authors: Fernandes Ana , Sanches Roberta , Matos Francielly , Massaro Juliana , Donadi Eduardo 
Published: January 2023

Abstract
Background/aims: HLA-G is expressed at maternal-fetal interface and is strongly involved on maternal-fetal tolerance. The 3' untranslated region of HLA-G gene presents an insertion (INS) and/or deletion (DEL) of a 14bp fragment, which is associated with stability and expression levels of HLA-G mRNA. The aim of this study was to analyze the hypothesis that the 14bp polymorphism can influence the HIV vertical transmission. Methods: Blood samples were obtained from 49 mother-child pairs (26 pairs with and 23 without vertical transmission). All children were born from HIV-positive mothers who did not receive antiretroviral therapy during pregnancy. The 14 pp polymorphism was detected by PCR-amplified DNA using specific primers. Statistical analyses were made by Fisher's exact test. This study was approved by the local ethics committee. Results: We did not detect significant differences in allele and genotype frequencies between HIV-infected and HIV-uninfected child; however, the presence of the D/D homozygous genotype was more frequent among mothers with HIV-infected child (p=0.05). In addition, the 14pb similarity among mother and child pairs was more frequent on vertical transmission (69%) than on its absence. Conclusion: The presence of the genotype (DEL/DEL), associated with high production of HLA-G, and the similarities of the 14bp DEL/INS genotypes between mother and child may favor HIV mother to child transmission.
SIV induced modulation of the enteric serotonergic response contributes to chronic immune activation (P3047)
Authors: Grishina Irina , Hirao Lauren , Sankaran-Walters Sumathi , Capitanio John , Dandekar Satya 
Published: January 2023

Abstract
Immune activation is a hallmark of SIV infection, which induces immune dysregulation through the course of infection. Serotonin (5HT) is a neurotransmitter, &gt;90% of which is made in enteric enterochromaffin (EC) cells, where it modulates gut motility and immune function. Though immune cells are functionally responsive to 5HT, its role in the gut has not been studied in context of SIV infection. We hypothesize that SIV infection alters 5HT regulation and signaling, contributing to chronic immune activation. During chronic SIV infection elevated levels of mucosal 5HT, decreased expression of 5HT reuptake transporter (SERT) and elevated numbers of EC cells were indicative of elevated extracellular 5HT availability. SERT expression correlated positively with CD4+ T-cell numbers, and inversely with viral replication and CD8+ T cell Interferon-gamma (IFNγ) production. Increase of 5HTRs 1A and 2A expression demonstrated potential involvement of 5HT signaling in cell activation and proliferation. Treatment of LPLs from SIV+ animals with 5HT resulted in increased percentages of CD14+ macrophages and CD11c+ mDCs producing IFNγ. Changes in expression of 5HT regulatory molecules, EC cell numbers, 5HTR profile and immune cell response to 5HT stimulation during chronic SIV infection implicate the intestinal serotonergic response as a potential mechanism contributing to chronic immune activation and highlight the virally disrupted interface between enteric neuronal and immune homeostasis.
Intrinsic CXCR5 expression is required to maintain long-lived antigen specific CD4 T cells during chronic Mycobacterium tuberculosis infection (P3013)
Authors: Moguche Albanus , Shafiani Shahin , Dihn Crystal , Larson Ryan , Clemons Corey , Urdahl Kevin 
Published: January 2023

Abstract
Chronic antigenic stimulation is known to cause T cell functional exhaustion and death. During Mtb infections, antigen specific CD4 T cells are subject to chronic antigenic stimulation but a sizeable population of these cells survives and maintains the ability to produce IFN-γ. How these cells are maintained is not yet understood. Mtb-specific CD4 T cells can be classified based on the surface expression of the inhibitory receptors PD1 and KLRG1. The PD1+ cells proliferate robustly but produce low amounts of IFN-γ while KLRG1+ cells proliferate less but produce large amounts of IFN-γ. Significantly, the PD1+ cells are capable of differentiating into KLRG1+ cells and not vice versa indicating that a self-renewing progenitor population may be contained within the PD1+ cells. On further characterization we have found that PD1+ cells are heterogeneous containing three different subsets based on expression of the chemokine receptor CXCR5 i.e. PD1+CXCR5hi cells that resemble Tfh cells, PD1+CXCR5int and PD1+CXCR5lo cells. We found that B cells were not required to maintain the Tfh like cells or overall Mtb-specific CD4 T cells. However, using mixed bone marrow chimeras we found that intrinsic CXCR5 expression on CD4 T cells is required to maintain Mtb-specific CD4 T cells. Taken together, these studies indicate that during Mtb infections, a subset of CD4 T cells capable of self-renewal is induced and intrinsic CXCR5 is important for its maintenance.
Neutrophil extracellular traps exhibit no bactericidal activity against Pseudomonas aeruginosa (P1255)
Authors: Gadjeva Mihaela 
Published: January 2023

Abstract
In CF lungs, PMN are the dominant cell responding to bacterial infection in the lungs. However, PMNs are incapable of preventing chronic colonization and contribute to host damage by excessive release of granule contents and formation of neutrophil extracellular traps (NETs) predominantly composed of DNA. It is currently unclear whether NETs serve to trap bacterial pathogens and, hence, facilitate bacterial colonization, or whether they have weak bactericidal activities. We investigated the kinetics, composition, and functional consequences of NET release in response to Pseudomonas aeruginosa, the most frequent bacterial colonizer of Cystic Fibrosis patients. We found that both non-mucoid and mucoid strains of P. aeruginosa were not sensitive to NET-mediated killing. This was not due to the inability of P. aeruginosa to induce NET formation by PMNs as NETs, released in response to P. aeruginosa, exhibited the typical NET composition. Overstimulation of NET release by PMA treatment prior to infection also failed to reduce the ability of P. aeruginosa to survive. Importantly, the presence of NETs hindered the bactericidal activity of complement. These findings suggest that targeting NETosis could provide an effective therapy for CF. To this end, we identified a host factor, termed, macrophage migration inhibitory factor, which facilitated PMN’s ability to NETose. Therefore, inhibiting MIF in this setting may be a significant innovation in therapy of CF lung disease.
Adverse role of influenza A virus-induced Nox1 in neutralizing antibody responses and survival against lethal viral challenge in mice. (P1407)
Authors: Hofstetter Amelia , De La Cruz Juan , Patel Jenish , McCoy James , Cao Weiping , Kim Jin , Diebold Becky , Belser Jessica , Tumpey Terrence , Katz Jacqueline , Sambhara Suryaprakash , Lambeth J. , Gangappa Shivaprakash 
Published: January 2023

Abstract
Highly pathogenic influenza viruses can elicit a severe cytokine storm, leading to acute lung injury (ALI), or in its more severe form, acute respiratory distress syndrome (ARDS). Reactive oxygen species (ROS) produced by NADPH Oxidase (Nox) enzymes of both the lung infiltrating cells and the lung epithelial tissue can contribute to lung injury directly or via inflammatory signaling pathways. Here, we present evidence that Nox1 expression is enhanced in vitro (A549 lung epithelial cells, 33-fold; THP-1 monocytic cells, 633-fold; HULEC lung endothelial cells, 27-fold) and in vivo (mouse lung tissue, 17-fold) in response to infection with influenza A virus. Notably, in A549 cells, Nox1 expression levels were enhanced by laboratory strains A/X31 (H3N2) and A/WSN/33 (H1N1), as well as A(H1N1)pdm09 clinical isolates (A/California/08/2009, A/Mexico/4108/2009, and A/Texas/15/2009) of influenza A virus. Nox1 induction was virus dose- and replication-dependent. However, Nox1-deficient mice had a higher survival rate (p=0.008) compared to wild-type controls in response to a lethal dose of A/PR8/1934 influenza. Improved survival of Nox1-deficient mice corresponded with increased (p=0.0006) flu-specific neutralizing antibody responses. These results suggest that therapeutic blockade of Nox1 deserves further attention as a possible adjunct therapy for influenza A-associated ALI/ARDS.
Expression of TREM-1 is triggered by flaviviruses: possible role in virus-associated innate immune responses (P1381)
Authors: Roe Kelsey , Nelson Jacob , Orillo Beverly , Verma Saguna 
Published: January 2023

Abstract
Activation of Triggering Receptor Expressed on Myeloid cells 1 (TREM-1), an immunoreceptor expressed mainly on immune cells results in a cascade of inflammatory effects including cytokine production. In addition, TREM-1 also modulates signaling cascades of other PRRs such as TLRs and NLRs. Engagement of the TREM-1 receptor via adaptor protein DAP12 leads to the activation of downstream kinases, mobilization of intracellular calcium and production of pro-inflammatory cytokines. Innate immune responses are essential for the clearance, dissemination and neurovirulence of West Nile virus (WNV), a neurotropic flavivirus, which has emerged in the U.S. as a significant cause of viral encephalitis in humans. However, the role of TREM-1 signaling pathway in immunity to flaviviruses is unclear. In this study we investigated the changes in the expression kinetics and activation of TREM-1 following WNV infection. Expression of TREM-1 was markedly increased in WNV-infected mouse immune cells and embryonic fibroblasts (MEFs) at 48 hrs after infection and in the mouse brain at day 8 after infection. Further, activation of TREM-1 using agonist antibody resulted in an increase in the levels of IFN-β and key cytokines in WNV-infected MEFs. Our results so far indicate a possible role of TREM-1 in the induction of inflammatory innate immune responses to WNV and further studies are ongoing to characterize unexplored mechanisms of TREM-1 associated with the pathogenesis of flaviviruses.
IKKϵ is targeted by pathogenic West Nile virus to evade host immune control (P1387)
Authors: Huang Albert , Perwitasari Olivia , Ramos Hilario , Suthar Mehul , Brassil Margaret , Blahnik Gabriele , Gale, Jr. Michael 
Published: January 2023

Abstract
Innate antiviral immunity and interferon (IFN) defenses are essential for the control of West Nile virus (WNV) infection. A pathogenic strain of the virus (WNV-TX) can suppress IFN actions by blocking JAK-STAT signaling, thus evading host IFN defenses. It was recently shown that IKKϵ directly regulates STAT1 activity by phosphorylating STAT1 on S708 to enhance IFIT2 expression and suppress WNV infection. However, the spectrum of interferon-stimulated gene (ISG) expression that is regulated by IKKϵ/STAT1 S708 signaling undergoing WNV infection and IFN signaling is not defined nor is it known if pathogenic WNV can evade these actions as a basis of disease. Here, we compared the transcriptomes of cells infected with pathogenic (WNV-TX) and non-pathogenic (WNV-MAD) strains of WNV to identify the genes specifically regulated by pathogenic WNV. Further, we compared the transcriptomes of IFN treated WT and IKKϵ KO cells to identify IKKϵ-dependent ISGs. These analyses allow us to identify genes that are shut down by pathogenic WNV in an IKKϵ-dependent manner to evade host immune response. Importantly, we also found IKKϵ-mediated induction of ISGs to be blocked by the anchored capsid portion of WNV-TX but not WNV-MAD. The anchored capsid of WNV-TX physically interacts with IKKϵ to mediate kinase suppression and a block in STAT1 S708 phosphorylation. Thus, IKKϵ is preferentially targeted by the anchored capsid of the pathogenic WNV to evade antiviral innate immunity and IFN actions.
CpGB DNA activates dermal macrophages and highly recruits inflammatory monocytes into the skin (P5120)
Authors: Mathes Allison , Christmann Romy , Affandi Alsya , Stifano Giuseppina , Lafyatis Robert 
Published: January 2023

Abstract
Toll-like receptor 9 (TLR9) recognizes DNA with unmethylated CpG motifs and evidence suggests that it is highly involved in several autoimmune skin diseases. This study investigated the effects of chronic TLR9 activation in the skin by identifying upregulated cytokines and chemokines and their roles in cell recruitment after subcutaneous treatment of TLR9 ligand, CpGB. Also, it established the importance of circulating and skin resident immune cells in potentiating this inflammatory response. CpGB DNA skin treatment dramatically induced an influx of CD11b+ F4/80+ macrophages, markedly increasing over 4 weeks of treatment, and an induction of IFNγ and TNFα expression. Chemokines, CCL2, CCL4, CCL5, CXCL9, and CXCL10, were highly induced in CpGB DNA-treated skin, although abrogation of these signaling pathways individually did not alter macrophage recruitment. TLR9 activation in the skin led to an increase in circulating CD11b+ CD115+ Ly6Chi inflammatory monocyte population following 1 week CpGB DNA treatment. Lastly, skin resident CD11b+ cells initially take up subcutaneous CpGB DNA and propagate the subsequent immune response. Overall, this study demonstrates that chronic TLR9 activation induces selective monocyte recruitment into the skin, likely derived from the population of inflammatory monocytes strikingly increased in the blood. Furthermore, it shows that macrophages are the key cells recognizing immune stimuli and initiating an inflammatory response in the skin.
Cholesterol crystal production by endothelial cells and its impact on early atherosclerosis development. (P5128)
Authors: Baumer Yvonne , William Boisvert 
Published: January 2023

Abstract
Atherosclerosis is an inflammatory disease that begins with a dysfunctional endothelial phenotype caused by endogenous factors such as blood lipid and cytokine/chemokine levels or exogenous factors like cigarette smoke and certain microorganisms. While performing experiments involving endothelial cells (EC) and lipoproteins we observed cholesterol crystal (CC) formation by the EC and decided to study if this phenomenon would contribute to early stages of atherogenesis. When EC were incubated with high but physiologic levels of LDL we observed CC formation within multivesicular bodies of EC and their subsequent transport and excretion to the basolateral side of EC. We then cultured human aortic endothelial cells on CC coatings and detected several pro-atherogenic changes in endothelial function such as increased permeability due to incomplete inter-endothelial junction formation, increased transmigration of mononuclear cells and decreased regeneration potential, indicating that the formation of subendothelial CC may be important for endothelial dysfunction in early atherogenesis. Interestingly, in ldlr-/- mice fed a high fat diet for only 1 week we could detect subendothelial CC deposition in the earliest stages of atherosclerosis. Our findings indicate the important role of EC in possibly creating the first “subendothelial space” through cholesterol metabolism and subsequent CC formation that may be critical for the very beginning of atherosclerotic plaque formation.
Selenoproteins regulate oxidative stress and inflammatory phenotype of endothelial cells (P5132)
Authors: Sordillo Lorraine , Corl Chris , Gandy Jeffery 
Published: January 2023

Abstract
Oxidative stress contributes to the pathology of inflammatory-based diseases by increasing the expression of vascular-derived adhesion molecules, cytokines and eicosanoids. Certain selenoproteins, such as glutathione peroxidase (GPX) and thioredoxin reductase, possess important antioxidant defense functions in endothelial cells that can counteract the damaging pro-inflammatory effects of oxidative stress. Using an oxidative stress model based on selenium (Se) deficiency in bovine aortic endothelial cells (BAEC), we sought to determine whether specific selenoproteins may contribute to the differential regulation of adhesion molecules, cytokines and eicosanoids during pro-oxidant challenge. Se supplementation reduced adhesion molecule expression, cyclooxygenase 2, and pro-inflammatory cytokine expression by BAEC when compared to Se-deficient BAEC. Subsequent results using GPX4 siRNA showed that this selenoprotein is at least partially responsible for controlling adhesion molecule expression and cytokine production during oxidative stress. These data provide evidence for the involvement of certain selenoproteins in the regulation of adhesion molecule expression, eicosanoid biosynthesis, and cytokine production in BAEC during pro-oxidant challenge. Further characterization of the role of selenoproteins in endothelial cell metabolism may provide new insights as to how Se may provide specific health benefits in combating inflammatory-based diseases.
Delivery of signal 0 by dendritic cell-derived IL-6 promotes naïve T cell trafficking across high endothelial venules (P5098)
Authors: Fisher Daniel , Muhitch Jason , Lu Theresa , Evans Sharon 
Published: January 2023

Abstract
Dendritic cells (DC) are master regulators of adaptive immunity, providing cognate antigen (signal 1) and costimulation (signal 2) required for T cell activation in addition to cytokines (IL-12, TNF, IL-1 and IL-6; signal 3) that drive T cell expansion. Here we show that DC play an unexpected role in shaping the size of the naive T cell pool within draining nodes by promoting trafficking across vascular checkpoints termed high endothelial venules (HEV). Immunization with bone marrow-derived mouse DCs matured ex vivo by TLR4 or TLR9 agonists (LPS and ODN-CpG, respectively), but not a TLR2 agonist (Pam3CSK4), increased the density of two HEV homing molecules, peripheral lymph node addressin (PNAd) and intercellular adhesion molecule-1 (ICAM-1). Elevated PNAd and ICAM-1 supported increased trafficking of naïve T cells early in the adaptive immune response (12-48 h), preceding the peak phase of proliferative expansion of endothelial cells lining HEV in draining nodes. Loss of a single cytokine, IL-6, from CD11c+CD11b+CD8α- immunizing DC abrogated the early effects on HEV adhesion. Induction of HEV adhesion further required CCR7 chemokine receptor-dependent access of IL-6-producing DCs to afferent lymphatics at the immunization site. We propose that DC-derived IL-6 functions as a previously unrecognized signal 0 to fine-tune HEV adhesion, thereby increasing the probability that rare Ag-specific T cells receive activating signals during the initial phase of adaptive immunity.
CRK/CRKL proteins regulate T cell migration and activation (P5104)
Authors: Huang Yanping , Clark Fiona , Park Tae-ju , Curran Tom , Burkhardt Janis 
Published: January 2023

Abstract
Crk adaptor proteins include three family members: CrkI and CrkII are from the alternatively spliced crk gene, and CrkL is from the crk-like gene. These ubiquitously expressed proteins play important roles in multiple signaling pathways. However, their functions in T cells are poorly characterized, partly because germline-deficiency for Crk or CrkL leads to lethality in mice. By breeding Crkflox/flox:CrkLflox/flox mice to CD4Cre mice, we generated mice conditionally deficient for both Crk and CrkL in mature T cells. These mice are viable and fertile. We find that T cells lacking both Crk and CrkL develop normally, but are defective in chemotactic responses to multiple chemokines. Further analysis revealed that while Rac1 activation is intact, Rap1 activation is perturbed, as is tyrosine phosphorylation of the Rap1 GEF C3G. Consistent with this, these cells exhibit reduced chemokine-stimulated adhesion to ICAM-1 and fibronectin, and defective diapedesis. Using a cutaneous DTH model, we show that Crk and CrkL are required for efficient T cell migration to sites of inflammation. In addition to regulating T cell migration, Crk proteins also control T cell activation. Double deficient T cells showed significant proliferative defects upon allogeneic antigen stimulation. These results demonstrate a key role for Crk proteins in T cell function. We are currently working on defining Crk/CrkL-dependent pathways and analyzing functions of Crk proteins in singly deficient T cells.