bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predominance of an unusual natural killer phenotype during recovery after natural killer cell depletion (36.23)
Authors: Alvarez Maite , Barao Isabel , Orr Mark , Lanier Lewis , Redelman Dog , Murphy William 
Published: January 2023

Abstract
Natural killer (NK) cells are considered as a front line defense against cancer and viral infection. Despite multiple studies based on NK cell development, the regulation of the maturation and differentiation of NK cells is still poorly understood. Shortly after bone marrow transplantation (BMT) we observed rapid appearance of an NK cell subset characterized by increased Ly49G2 median fluorescence intensity (MFI) along with the activation marker Thy1.2. This subset was no longer detectable at 28 days post-BMT. To determine if this activated mature subset appeared as a result of the cytoreductive conditioning versus normal differentiation, we assessed NK cell recovery on mice depleted with anti-NK1.1. We found a significant increase in the percentage of NK cells that express higher Ly49G2 MFI as well as Thy1.2, an indication of their activated state, on day 3 and 9 post-depletion which decreases to levels similar to resting mice on day 14. These results suggest that lymphopenic conditions after irradiation as well as cell depletion lead to a reduction of NK cells suggesting the lack of competition between the remaining cells may make endogenous cytokines available for developing NK cells that become highly activated.
Visualization of type 2 NKT cell development in the thymus (36.55)
Authors: Hamad Abdel , Xiao Zuoxiang 
Published: January 2023

Abstract
Beside CD4 and CD8 αβT cells, several minor but important T cell subsets develop in the thymus. These include NKT cells, which are selected on MHC class 1b molecule CD1d. NKT cells are broadly divided into type 1 NKT cells, which express an invariant TCR and bind αGalCer-CD1d tetramer and type 2 NKT cells, which express non-invariant TCRs and do not bind αGalCer-CD1d tetramer. Significance advances in development of type 1 NKT cells have been made by using αGalCer-CD1d tetramer for visualization of their thymic development. However, very little is known about development of type 2 NKT cells due to the lack of a specific marker for their identification in the thymus. Here we show that the highly conserved heparan sulphate proteoglycan syndecan-1 (sdc1) is selectively expressed by a small subset of TCRαβ thymocytes. Unlike mainstream i.e sdc1-TCRβ+ thymocytes, the majority of sdc1+ TCRβ+ thymocytes are CD4-CD8-(DN) T cells whose development is CD1d-dependent and are not reactive to αGalCer-CD1d tetramer and hence are type 2 NKT cells. Functional maturity of this subset is indicated by their production of Th2 cytokines in vitro stimulation with CD3/CD28 or CD1d beads. Sdc1 appears to play an important role in regulation of cytokine production and homing of type 2 NK T cells. Identification of sdc1 as a specific marker for type 2 NKT cells in the thymus will facilitate understanding their development.
Requirement of MMP2 and MMP9 for lung innate immune defense against Streptococcus pneumoniae infection (37.34)
Authors: Hong Jeong Soo , Greenlee Kendra , Lee Seung-Hyo , Song Li-Zhen , Shan Ming , Pitchumani Ramanan , Chang Seon Hee , Park Pyong Woo , Bidani Akhil , Dong Chen , Werb Zena , Corry David , Kheradmand Farrah 
Published: January 2023

Abstract
The first wave of host innate immune response to bacterial invasion is central to protection against microbial pathogens. Identification of the critical local mediators in the lung that provide early protection against bacteria is essential for a complete understanding of the molecular mechanism(s) underlying host defense. In an acute model of Streptococcus pneumoniae TIGR4 (SP-TIGR4) lung infection, we found MMP2 and MMP9 double null (MMP2/9-/-) were more susceptible to death when compared to wild type (WT) mice. In response to SP-TIGR4 challenge, MMP2/9-/- mice recruited more polymorphonuclear cells (PMNs) to the lung, however lungs and spleens isolated from the infected mice showed higher systemic bacterial load in the absence of MMP2 and MMP9. Consistent with an increase in lung PMNs, MMP2/9-/- mice showed significant increase in levels of IL-17, IP-10 and RANTES in BAL fluid. In vitro studies showed MMP2 mediated inhibited function of IL-17A proinflammation and MMP9 was related to ineffective bacterial phagocytosis and opsonization of PMNs. Taken together, these data support a protective role for MMP2 and MMP9 in host immune responses in early phase of bacterial infection.
An attenuated innate immune response to a clinical strain of respiratory syncytial virus (RSV) in human monocyte derived dendritic cells (MDDC) (37.43)
Authors: Hillyer Philippa , Chen Aaron , Schramm Lynnsie , Mane Viraj , Navarro Maria , Luongo Cindy , Raviv Nataly , Collins Peter , Rabin Ronald 
Published: January 2023

Abstract
RSV clinical strain 19 was isolated from a severely affected infant and was characterized in a model in which mice develop severe disease defined by enhanced mucous secretion, IL-13 expression, and low expression of IFN-α compared to infection with the lab strain A2. We compared the innate response induced by RSV strain 19 with strain A2 in human MDDC using a qRT-PCR based array and a novel qRT-PCR assay we developed that discriminates among all IFN-α and IFN-λ subtypes and also includes IFN-β. Human MDDC expressed a similar profile of inflammatory and IFN response genes (IRG) to both RSV strains. The response to strain 19, however, was attenuated for many IRG and inflammatory genes, including CXCL9, CXCL10, CCL2 and genes associated with the RIG-I pathway. Similarly, MDDC expressed IFN-α1, IFN-β, IFN-λ1, and -λ2 in response to either strain, but strain 19 expressed lower levels of each. Another IFN subtype, IFN-α14, was expressed by 5 donors in response to strain A2 but was undetectable in response to strain 19. IFN-α protein, however, was undetectable in 9 of 10 supernatants from strain 19 in contrast to 1 of 10 supernatants from A2 infected cells. Evasion or active suppression of the IFN-α, -β or -λ response may explain the enhanced pathogenicity of strain 19. The qualitative difference in IFN-α14 expression in response to A2 but not 19 suggests a potentially important role for this subtype.
Molecules involved in the NFκB signaling pathway are down regulated in neonatal alveolar macrophages resulting in reduced response to Pneumocystis infection (37.7)
Authors: Kurkjian Cathryn , Hollifield Melissa , Garvy Beth 
Published: January 2023

Abstract
Neonates are unable to clear Pneumocystis (PC) infection with the same efficiency as adults. The alveolar macrophage (AM) phenotype of neonates during infection varies from that of adults, leading to a delayed inflammatory response and a slower clearance of infection. Upon infection with PC, neonatal AMs appear to maintain an alternatively activated phenotype, where as adults tend to adopt a classical AM phenotype. Previous data from our lab has shown that an elevated expression of TGFβ in neonatal lungs suppresses the ability of AMs to respond to PC. Use of a conditional smad4 KO model in which TGFβ signaling is defective in macrophages allowed us to show that blocking the TGFβ signaling pathway improves clearance of PC in neonatal mice. To further examine the response of neonatal AMs, in vitro immunoflourescence assays were performed to examine NFκB translocation to the nucleus. We found that, while neonatal AMs translocate NFκB in response to zymosan, they remain unresponsive to PC cysts. This data suggests that the unresponsiveness of neonatal AMs to PC infection may be due in part to reduced response of macrophages to PC cysts, in addition to the immunosuppressed lung environment. We hypothesize that the down regulation of molecules involved with NFκB translocation to the nucleus results in the reduced response of AMs to PC.
Cell-intrinsic Transforming Growth Factor-β signaling mediates virus-specific CD8+ T cell deletion and viral persistence in vivo (39.12)
Authors: Tinoco Roberto , Alcalde Victor , Yang Yating , Sauer Karsten , Zuniga Elina 
Published: January 2023

Abstract
Chronic viral infections represent a major biomedical problem. Although, in both humans and mice, viral persistence has been associated with insufficient numbers and/or function of CD8+ T cells, the underlying mechanisms are still unclear. By using Lymphocytic choriomeningitis virus in its natural murine host, we found that enhanced and sustained Transforming Growth Factor-β (TGF- β),expression and phosphorylation of its signaling mediator, Smad-2, were distinctive features of virus-specific CD8+ T cells during chronic versus acute viral infections in vivo. Selective attenuation of TGF-β pathway in T cells decreased the expression of the pro-apoptotic protein Bim and increased survival and numbers of virus-specific CD8+ T cells. Under these conditions, virus-specific CD8+ T cells had enhanced cytotoxicity, increased production of anti-viral cytokines, and down-regulation of inhibitory molecules. The end result was rapid virus eradication and generation of an effective memory T cell response that protected the host upon subsequent challenge. Notably, we found that cell-intrinsic TGF-β signaling was responsible for virus-specific-CD8+ T cell apoptosis but was not necessary for their functional exhaustion. Our findings demonstrate that sustained TGF-β-Smad signaling is a hallmark and master regulator of CD8+ T cell responses during chronic viral infections in vivo.
Enhanced CD8+ T-cell immunity following sequential flavivirus vaccines (39.19)
Authors: Singh Rekha , Green Sharone 
Published: January 2023

Abstract
Flaviviruses are arthropod-borne, RNA viruses of the Flaviviridae family. Flavivirus antigen-specific CD8+ T-cells are important in virus clearance. Primary exposure to a virus causes priming of CD8+ T-cells by virus-derived immunodominant peptides, leading to clonal differentiation and proliferation of effector cells followed by contraction and memory generation. ChimeriVax™ Flavivirus vaccines contain the nonstructural genes of the yellow fever (YF) vaccine and the prM and E genes of heterologous flaviviruses such as Japanese encephalitis (JE) and West Nile (WN) viruses. These chimeric vaccines induce both humoral and cell mediated immunity, however their potential to generate cross-reactive CD8+ T-cell responses to heterologous flaviviruses has not been investigated. In this study, mice were immunized with YF, YF/JE, or YF/WN vaccines followed by secondary homologous or heterologous immunization. We examined the hierarchy and function of CD8+ T-cell responses to a variable envelope epitope with those directed against a conserved immunodominant YF NS3 epitope. Using cell based immunological assays (ELISPOT and ICS), we found that the secondary immunization with heterologous chimeric flavivirus vaccines generate an enhanced cross-reactive CD8+ T-cell response that was dependent on the sequence of the primary immunization. Present results suggest that controlled exposure to multiple related flavivirus vaccines may lead to enhanced protection against related flaviviruses.
Severity of Epstein-Barr Virus (EBV)-induced infectious mononucleosis correlates with frequency of cross-reactive influenza M1-specific memory CD8 T cells (39.31)
Authors: Aslan Nuray , Watkin Levi , Sullivan John , Luzuriaga Katherine , Selin Liisa 
Published: January 2023

Abstract
Cross-reactive memory T cells specific to previously encountered influenza A contribute to the characterisitic lymphoproliferation of EBV-associated infectious mononucleosis (IM). In HLA-A2+ IM patients, influenza M158 (IAV-M1)-specific CD8 memory T cell responses cross-reacted with two different EBV lytic epitopes, BRLF-1190 (10/10) and BMLF-1280 (14/26). Disease severity of IM did not correlate with viral load. Interestingly, instead disease severity directly correlated with the percentage of Flu-M1-specific CD8 T cells but not with either EBV-BMLF-1, or -BRLF-1-specific responses. In addition, 8/19 IM patients demonstrated some intra-viral cross-reactivity between EBV-BRLF-1 and -BMLF-1 responses. These cross-reactive T cell responses were observed in all IM patients but different patterns of cross-reactivity occurred in each individual concerning the specific epitopes involved and their time of appearance after infection. A number of unique features of the TCR of the highly cross-reactive BRLF-1 epitope were noted. BRLF-1 T cell responses were of very high avidity. There was tremendous variation in the Vbeta/Valpha usage between different individuals, even in the same individual over time and this could be further modulated by peptide concentration in vitro. Cross-reactive BRLF-1 responses only became apparent at high antigen doses such as might occur during different phases of IM.
Structural Determinants of IFNα Distinguish Antiviral and Potentially Toxic Functions. (39.7)
Authors: Vazquez Nancy , Schmeisser Hana , Bekisz Joseph , Zoon Kathryn , Wahl Sharon 
Published: January 2023

Abstract
Interferon alpha (IFNα), a cytokine with multiple functions in innate and adaptive immunity and a potent inhibitor of human immunodeficiency virus (HIV), exerts antiviral activity, in part, by enhancing apolipoprotein B mRNA-editing enzyme-catalytic polypeptide-like 3(APOBEC3) family members. Although IFNα therapy is associated with reduced viral burden, this cytokine also mediates immune dysfunction and toxicities. Through detailed mapping of IFNα receptor binding sites, we generated IFNα hybrids and mutants and determined that structural changes in the C-loop influencing receptor interactions alter IFN’s ability to limit retroviral replication. Selective IFNα constructs differentially block HIV replication and their directional magnitude of inhibition correlates with elevated APOBEC3 levels with less significant changes in transcription of other antiviral molecules such as TRIM22 and PKR. Besides participation of the JAK-STAT pathway, we uncover previously unappreciated roles for NFκB, CAMK and PI3K signaling pathways in induction of APOBEC3 by the IFN constructs. Importantly, certain mutants exhibited reduced toxicity as reflected by induced indoleamine 2,3-dioxygenase and TNFα compared with intact IFN, suggesting discreet and shared intracellular signaling pathways. Defining IFN structure and function relative to APOBEC and other antiviral genes may enable the design of novel IFN-related molecules preserving beneficial antiviral roles while minimizing negative effects.
The CD8+ T cell response to Brucella melitensis during acute vs. chronic infection (40.24)
Authors: Durward Marina , Harms Jerome , Magnani Diogo , Eskra Linda , Splitter Gary 
Published: January 2023

Abstract
In areas of endemic brucellosis, prevention of infection via vaccine would be far more cost-effective than the World Health Organization suggested regimen of antibiotics. As with other intracellular organisms, subunit or killed vaccines present very limited efficacy. The rationale for an improved Brucella melitensis vaccine requires a greater understanding of the host-pathogen relationship. Using bioinformatics coupled with practical experiments in the BALB/c model of brucellosis, we have identified two Brucella epitopes and show their capacity to elicit specific CD8+ T cells that kill effectively in vivo. Additionally, as seen by microarray, gene transcripts that contain these epitopes are significantly and differentially expressed following Brucella infection of macrophages. Specific CD8+ T cells are present and functional following infection; however, reactivation of disease still occurs in up to 30% of human patients after antibiotic treatment. Our current work using Brucella specific MHC Class I tetramers focuses on the presence and persistence of CD8+ T cell memory during chronic brucellosis. Investigation of the functional potential of this memory fraction of CD8+ T cells will fill a gap in our understanding of the immunological response to this often asymptomatic, persistent infection.
Researching Type 1 Diabetes (41.10)
Authors: Judson Peter , Piccirillo Ciriaco 
Published: January 2023

Abstract
Research into the immunoregulation of type I diabetes (T1D), (an autoimmune disease that results in the destruction of insulin producing B cells in the pancreas), is the focus of this curriculum unit. The unit entitled “Researching Type I Diabetes” has been developed for high school students. This unit is designed to be used in classes such as health science, biology, or honors biology. The unit begins with a lesson on the immunoregulation of T1D via the use of a roundhouse diagram activity. Students then learn about the NOD mouse as a model in T1D research, and the legal and ethical aspects of using animals in medical research, to complete a persuasive writing activity involving bioethics. The third lesson requires students to follow a mouse dissection protocol. Following this protocol, students dissect the major organs of the mouse’s immune system (thymus and spleen) to isolate peripheral lymphatic nodes. Then the students observe a teacher demonstration of flow cytometry and cell sorting and why they are essential tools in the understanding of the immunoregulation of the disease. The culminating component of this unit is a “Web Quest,” in which students role-play the various roles involved in clinical and experimental research of T1D. The roles include: scientists, T1D patients, graduate students, physicians, and institutional review board members. Consequently, the students produce and present the results of their “Web Quest” to their classmates in a PowerPoint format.
Effect of a compromised inflammatory response on influenza virus infection (42.17)
Authors: Campbell Gillian , Dransfield Ian , Nash Tony , Dutia Bernadette 
Published: January 2023

Abstract
The inflammatory response to influenza virus infection in vivo represents a major determinant of the damaging immunopathology associated with cytokine storms and fatal infections. We hypothesised that production of inflammatory cytokines such as inducible nitric oxide synthetase and TNF-α by classically activated macrophages plays a major role in development of severe disease. However, alternatively activated macrophages might ameliorate symptoms. We therefore generated polarized macrophages from wild type and IFN-γR-/- mice using IFNγ and IL-4. Following infection with influenza A/WSN/33, we monitored the levels of virus and assessed the impact on cytokine expression profiles in the different macrophage populations. Infection of macrophages resulted in a predominantly inflammatory phenotype in both classically and alternative activated populations. However, alternatively activated macrophages were more readily infected and exhibited reduced viability. In vivo infection showed that wild type mice produce increasing levels of inflammatory cytokines as viral lung titres decline. Pilot studies suggest that IFN-γR-/- mice, which lack the ability to produce a classical macrophage response, are less susceptible to infection, showing no clinical symptoms or elevated pro-inflammatory cytokines and are able to clear virus more readily. Experiments are ongoing to elucidate the role of different macrophage phenotypes in control of influenza virus infection and immunopathology.
NLRP3 directs inflammasome activation in response to live F. tularensis infection (42.20)
Authors: Atianand Maninjay , Shah Aaloki , Duffy Ellen , Kar Supriya , Malik Meenakshi , Harton Jonathan 
Published: January 2023

Abstract
Detection of intracellular pathogens is facilitated by members of the nucleotide binding-leucine rich receptor (NLR) family. The role of ASC/Caspase-1 axis for protective innate immunity against Francisella infection is well established, however the NLR(s) involved in initiation of innate immune responses during Francisella infection are yet unknown. Here we demonstrate that human NLRP3 mediates inflammasome dependent IL-1β production following Francisella infection. Notably, both human NLRP3 and mouse Nlrp3 are sufficient to assemble functional inflammasomes in HEK293T cells infected with Francisella. Furthermore, our results also support the existence of more than one Francisella-responsive cytoplasmic inflammasome complex and suggest that intrinsic differences in bacterial strains as well as monocyte-macrophage differentiation status influence inflammasome-dependent innate immune responses to Francisella.
Herpetic Stromal Keratitis (HSK) lesion severity correlates with the amount of pro-inflammatory neuropeptide Substance P in the cornea (42.21)
Authors: Twardy Brandon , Channappanavar Rudragouda , Suvas Susmit 
Published: January 2023

Abstract
The cornea is richly supplied by nerve fibers that express a variety of biologically active neuropeptides. In this report, we looked into the possibility that after ocular herpes simplex virus-1 (HSV-1) infection of C57BL/6, the level of expression of neuropeptide SP in the cornea correlates with the development of HSK lesions. Our results showed that after ocular HSV-1 infection of C57BL/6 mice, about 60-70% of the infected corneas developed severe HSK lesions (corneal opacity ≥3 and angiogenesis ≥8) whereas, 30-40% developed mild HSK lesions (corneal opacity ≤1 and angiogenesis ≤5). No significant difference in the viral load was determined when analyzed between the corneas with mild or severe HSK lesions at different time-points post-infection. However, a strong influx of CD4 T cells and neutrophils were evident in the corneas with severe HSK lesions when compared to those with mild lesions at day 15 post-infection. In addition, corneas with mild HSK lesions had lower levels of IL-6, IL-2, IFN-g and IL-1 Ra in comparison to the corneas with severe HSK lesions as determined on day 15 post-infection. Most importantly, corneas with severe HSK lesions had significantly higher levels of neuropeptide SP in comparison those with mild HSK lesions, when determined on day 15 post-infection by using Immunofluorescence and EIA technique. We are looking into the possibility that neutralization of SP in the cornea impedes the development of severe HSK lesions in a mouse model.
Toll-like receptor 2 (TLR2) is critical for controlling local herpes simplex virus replication and for the generation of potent T lymphocyte immune responses (42.23)
Authors: Kollias Christina , Jennings Stephen 
Published: January 2023

Abstract
Herpes simplex virus (HSV) is a ubiquitous human pathogen that can cause a devastating encephalitis in rare instances [Herpes simplex encephalitis (HSE)]. Toll-like receptors (TLRs) are evolutionarily conserved pattern recognition receptors capable of early detection of invading pathogens. The importance of TLR signaling in resistance to HSV has recently been studied using genetic knock-out animals. Endosomally-expressed TLR9 recognizes HSV DNA and is important for early type I interferon production and prevention of central nervous system (CNS) infection. In contrast, the role of surface-expressed TLR2 in HSV immunity is unclear. We set out to study the role of TLR2 signaling in a cutaneous lip infection model of HSV in mice. Here we report the role of TLR2 signaling in response to HSV as measured by viral replication in the skin and in the CNS. Additionally, the role of TLR2 signaling on the generation of adaptive immune responses is reported. Future experiments aim to analyze the specific role of TLR2 signaling at the level of microglia. We plan to assess levels of inflammatory mediators in the brain as well as leukocyte recruitment to the CNS. These studies are designed to delineate the role of TLR2 signaling in different topological environments in a model of viral-induced encephalitis, with the hopes of developing novel therapies for patients with HSE.