bluuebunny/crossref_metadata_2025_split huggingface dataset:
Promotion of Th1/Th2 immunity with anti-TGF-β treatment protects mice against Neisseria gonorrhoeae infection and induces immune memory (40.22)
Authors: Liu Yingru , Russell Michael 
Published: January 2023

Abstract
Infection with N. gonorrhoeae triggers an intense inflammatory response characterized by an influx of neutrophils, yet natural infection does not induce effective specific immunity or immune memory. Our previous studies have demonstrated in a murine model of vaginal gonococcal infection that innate immunity governed by Th17 cells was the mainstay of the immune responses elicited by this pathogen. Herein we show in vitro that N. gonorrhoeae could specifically inhibit Th1 and Th2 responses of mouse CD4 T cells, but enhance Th17 response. We found that N. gonorrhoeae increased production of TGF-β by mouse lymphocytes in vitro, and concomitantly suppressed Th1/Th2 cytokines. In mouse vaginal explant cultures, the high constitutive production of TGF-β strengthened the suppressive effect of N. gonorrhoeae on Th1/Th2 responses. Anti-TGF-β, but not anti-IL-17, could divert the immune response to N. gonorrhoeae from Th17 towards Th1/Th2 modes. ELISA, microarray and flow cytometry studies indicated that when mice infected with N. gonorrhoeae were treated with anti-TGF-β, the host Th17 immune response was diminished, while Th1/Th2 responses were enhanced. Anti-TGF-β treatment led to faster clearance of infection and induced protection against secondary challenge, which did not occur in control-treated mice. Our results suggest that N. gonorrhoeae suppresses Th1/Th2-mediated adaptive immune response, and that this effect can be manipulated to enhance specific protective immunity.
TNF-α and Th17 collaborate to induce airway neutrophilia during persistent fungal infection in a MyD88 and Dectin-1-dependent fashion (40.23)
Authors: Fei Mingjian , Bhatia Shikha , Oriss Timothy , Khare Anupriya , Yarlagadda Manohar , Kolls Jay , Iwakura Yoichiro , Ray Prabir , Ray Anuradha 
Published: January 2023

Abstract
Aspergillus fumigatus is a fungus that induces allergic bronchopulmonary aspergillosis (ABPA), a disease exhibiting both airway eosinophilia and neutrophilia. The disease is acquired through the inhalation of spores, which are cleared efficiently in healthy humans but not in patients with cystic fibrosis or asthma. The impaired clearance and sustained inflammation contribute to the pathogenesis of ABPA. Neutrophils are important in host defense, but uncontrolled neutrophilia causes lung pathology in ABPA. We have developed an animal model of ABPA that mimics persistent fungal stimulation in ABPA. Interestingly, the model produced different outcomes in BALB/c and C57BL/6 mice with high neutrophilia in the former but low neutrophilia and high eosinophilia in the latter, which provided us with an opportunity to study the mechanisms underlying excessive airway neutrophilia. Our results show that IL-17A, which has been associated with neutrophilia in many models, was induced at similar levels in both strains. However, the BALB/c mice expressed high levels of TNF-α and collaboration between IL-17A and TNF-α was essential in inducing the high neutrophilia in BALB/c mice. Our investigations in MyD88-/- and Dectin-1-/- mice show an important contribution of both pathways in inducing high TNF-α and IL-17A responses in BALB/c mice. Taken together, we identify a novel mechanism involving the cooperation of TNF-α and Th17 for the regulation of airway neutrophilia in Aspergillus infection.
Nasopharyngeal colonization by Streptococcus pneumoniae elicits long-lasting immune responses that confer protection from invasive lung infections. (40.25)
Authors: Gerstein Rachel , Maung Nang , Goodwin Aaron , Cloherty Erin , Muñoz-Elías Ernesto , Camilli Andrew , Leong John 
Published: January 2023

Abstract
Streptococcus pneumoniae can cause life-threatening pulmonary and systemic infection. However, an apparent paradox is that the bacterium resides, usually harmlessly, in the nasopharynx of many, if not most people. Humoral immunity is thought to be the primary defense against serious pneumococcal infection, and we hypothesized that nasopharyngeal colonization results in the generation of an antibody response that provides long-term protection against lung infection. In fact, we found that intranasal colonization resulted in a pneumococcal-specific antibody response and protection from a subsequent high-dose S. pneumoniae lung challenge that is lethal in naïve mice. This protection lasted many weeks and seemed to be independent of the pneumococcal capsular serotype, suggesting that natural infection might trigger an immune response to a conserved antigen (or antigens) that provides protection from a broad range of S. pneumoniae strains. We found that T cell-deficient (TCR δβ-/-) mice survived both the intranasal inoculation and lung challenge better than B cell-deficient (μMT-/-) mice. Our data suggest that nasopharyngeal colonization elicits an antibody response that protects against lethal S. pneumoniae lung infection and this protective response might consist of both T-cell dependent and T-cell independent B cells.
Investigating mechanisms for limited CD8 T-cell expansion in experimental visceral leishmaniasis. (40.5)
Authors: Bankoti Rashmi , Stager Simona 
Published: January 2023

Abstract
Leishmania donovani, a causative agent of visceral leishmaniasis, establishes chronic infections in the spleen in humans and in mice. Thus far, the only cells that are known to be able to reduce the splenic parasite burden following immunotherapy in mice are antigen-specific CD8+ T-cells. Yet, L. donovani appears to be able to evade this defense by limiting the expansion and effector functions of CD8+ T-cell responses. Since a strong clonal expansion of antigen-specific CD8+ T-cells has been shown to be essential for the control of several pathogens, we are particularly interested in dissecting the mechanisms by which L. donovani interferes with the expansion of Leishmania-specific CD8+ T-cells. We first investigated possible inhibitory pathways that may be involved in the suppression of expansion of CD8+ T-cells. Surprisingly, we found that blocking either B7H1 or LAG-3 did not affect the early expansion and functionality of CD8+ T cells. We next evaluated the possible role of IL-10 in limiting the expansion of CD8+ T cells. IL-10R blockade resulted in increased expansion and greater cytotoxic capacity of parasite-specific CD8+ T-cells. However, depletion of Tregs and/or NK cells, which are thought to be the major sources of IL-10 during acute infection, did not improve the magnitude of expansion nor the ability of CD8+ T cells to produce Granzyme B and IFN-γ. Other IL-10 producing cell populations and inhibitory pathways will be discussed.
Tracking the Re-emerging Traits of Tuberculosis (41.9)
Authors: Mottley Hana , Salgame Padmini , Bhatt Kamlesh , Uzelac Aleksandra , McBride Amanda 
Published: January 2023

Abstract
Tuberculosis (TB) is a re-emerging health concern infecting nearly one third of the world’s total population and causing 1.5 million human deaths. These bacilli bacteria express multiple favorable adaptations including numerous antibiotic resistant strains. During my summer laboratory experience, I worked on a research team within the Emerging and Re-emerging Disease laboratory. The focus of the research is to develop baseline concentration numbers of cytokine messengers released by mouse cells after mice are infected with a new lab strain of TB and to test cells for the presence of four different cytokine types: TNF α, P40, P70, and INF γ in order to understand which TB strain induces which cytokines type. ELISA tests determine the type and concentration of cytokines while PCR testing determines what type of proteins are synthesized within infected cells due to the signals induced by the tested TB strain. I have adapted my laboratory experience into an educational unit which demonstrates how the KO mice that are used in the TB research laboratory are created for my students. This will provide my students with a real-world view into the biotechnological world.
Caspase-1 independent IL-1β Production is critical for MyD88-mediated host resistance to Mycobacterium tuberculosis (42.13)
Authors: Mayer-Barber Katrin , Barber Daniel , Shenderov Kevin , White Sandra , Wilson Mark , Cheever Allen , Kugler David , Sutterwala Fayyaz , Sher Alan 
Published: January 2023

Abstract
Host resistance to Mycobacterium tuberculosis (Mtb) requires the TLR/IL-1R adaptor MyD88. To investigate the contributions of TLR versus IL-1R mediated signals in MyD88 dependent control of Mtb, we compared the outcome of Mtb infection in MyD88, TRIF/MyD88, IL-1R1 and IL-1β-deficient mice. All four strains displayed acute mortality with highly increased pulmonary bacterial burdens and necrotic lung pathology suggesting a major role for IL-1β signaling in determining the MyD88 dependent phenotype. Unexpectedly, the infected MyD88 and TRIF/MyD88-deficient mice, rather than being defective in IL-1β expression, displayed increased cytokine levels relative to WT animals, arguing that MyD88 regulates host resistance to Mtb at the level of IL-1β/IL-1R1 signaling rather than TLR-mediated triggering of cytokine production. Similarly, infected mice deficient in caspase-1 and ASC, which have critical functions in inflammasome mediated IL-1β processing, showed unimpaired IL-1β production and importantly, were considerably less susceptible to infection than IL-1β deficient mice. Thus, our data argue that the production of mature host-protective IL-1β during Mtb infection can occur independently of caspase-1 activation and ASC-containing inflammasomes. Together our findings reveal a critical role for IL-1β in acute host resistance to Mtb and indicate that during this bacterial infection the cytokine can be generated by a mechanism that does not require TLR signaling or caspase-1 cleavage.
IFN-γ exerts antiviral activity against polyomavirus infection (42.14)
Authors: Wilson Jarad , Lin Eugene , Pack Christopher , Hadley Annette , Lukacher Aron 
Published: January 2023

Abstract
CD8 T cells use both cytolytic and noncytolytic effector mechanisms to eliminate infectious pathogens. Using the mouse polyoma virus (MPyV) system, we have previously shown that TNFa, Fas/FasL, and the perforin/granzyme pathways are dispensable for viral control and susceptibility to MPyV-induced tumors. Here, we investigated whether IFN-γ may be an important effector mechanism for limiting viral burden and tumorigenesis. Using Western analyses for early region nonstructural viral T antigens, as well as FACS analyses of cells infected by a novel recombinant MPyV carrying an intra-T antigen HA epitope tag, we found that IFN-γ reduces expression of viral T antigens in a dose-dependent fashion. Compared to MPyV-infected wild type C57BL/6 mice, IFN-γ receptor KO mice had a 1-log higher viral load during acute infection in most organs, as well as during the persistent phase of MPyV infection; notably, 3-log higher viral genome copies were present in the kidneys, a major site of persistence by both murine and human polyomaviruses. This increase in viral burden was not due to a lack of responding cells, as fully functional virus-specific CD8 T cells were found during the entire course of infection in IFN-γR KO mice at levels similar to those seen in wild type mice. Studies are underway to determine if IFN-γ receptor KO mice are susceptible to PyV tumorigenesis and to investigate the importance of IFN-γ as a critical CD8 antiviral effector function in MPyV infection.
Cellular immunogenicity of an Ad35GGRIN+ENV and MVA-CMDR prime-boost vaccine regimen. (42.3)
Authors: Kim Silvia , Currier Jeffrey , Cox Josephine , Excler Jean-Louis , Sayeed Eddy , Robb Merlin , Kim Jerome , Michael Nelson , Marovich Mary 
Published: January 2023

Abstract
Newer HIV-1 vaccine strategies use heterologous prime-boost regimens to stimulate broader immune responses. We tested 2 heterologous vectors with heterologous HIV-1 gene inserts: Ad35GRIN+Ad35ENV and MVA-CMDR. The Ad35GRIN+Ad35ENV vaccine is comprised of two vectors containing sequences from HIV-1 subtype A (GRIN=gag, rt, int and nef and ENV=env). MVA-CMDR contains genes from HIV-1 subtype CRF01_AE (gag, env and pol). Balb/c mice (5/group) were immunized according to the following schema: Group 1:MVA-CMDR-MVA-CMDR; Group 2:MVA-CMDR-Ad35GRIN+ENV; Group 3:Ad35GRIN+ENV-MVA-CMDR; Group 4:Ad35GRIN+ENV-Ad35GRIN+ENV. Immunogenicity testing was performed at 2 weeks post boost: ELISPOT, ICS (CD107a, IFNγ, TNFα and IL-2) and pentamer (H-2Kd) Gag epitope staining were used. A variety of stimuli were used to define responses to inserts and vectors. Insert-specific immune responses were detected in all groups. The best combination was Group 3. Notably, there was a shift from a focused vector response in Group 1 to an insert response in Group 3 (0.78% CD8+INFγ gag pool response and 4.24% CD8+INFγ MVA response in Group 1 vs 5.74% CD8+INFγ gag pool response and 0.61% CD8+INFγ MVA response in Group 3). The relative contributions of vector versus insert are not clear. It appears that the insert response is dominant in the heterologous vector format and that subtle differences in cross-reactive populations can be revealed using the pentamer (H-2Kd) Gag epitope staining.
Investigation of TLR ligand-generated inflammatory signals for the induction of high magnitude memory CD8+ T lymphocyte responses (42.8)
Authors: Nelson Michelle , Johnson Alison , Chu Chin-Fun , Milligan Gregg 
Published: January 2023

Abstract
Most currently used vaccines elicit antibody and CD4+ T lymphocytes, but protection against some pathogens may also require a CD8+ T cell response. We are examining the ability of specific TLR agonists to stimulate a specific third signal, such as IL-12 and type 1 interferons, in bone marrow-derived dendritic cells (BMDC) necessary for appropriate development of antigen-specific memory CD8+ T cells against HSV-2. TLR4 (MPL) and TLR9 (CpG) ligands elicit high IL-12 and low IFN-α/β, while TLR3 (Poly(I:C)) ligands generate the opposite cytokine response. Initial in vitro studies demonstrated that gB peptide-specific CD8+ T cells co-cultured with gB-pulsed, TLR ligand-treated BMDC had a more activated phenotype, but there was little difference in CD8+ T cell proliferation when compared to media-treated BMDC cultures. Upon restimulation, the activated CD8+ T cells produced high quantities of TNF-α, IFN-γ, and granzyme B, but variation between groups was minor. These results suggest the choice of TLR ligand for stimulation had little impact on CD8+ T cells in vitro. Further experiments will focus on examining the lymphoid tissues to which our CD8+ T cells reside, their activation status, cytokine production profiles, and cell surface chemokine receptor expression directed by in vivo delivery of gB-pulsed, TLR ligand-treated BMDC. We believe that different TLR ligands will differentially shape the memory response, in turn, providing greater protection from subsequent infection.
Plant Polysaccharide Activates Macrophage to Clear Francisella tularensis Infections (42.9)
Authors: Skyberg Jerod , Holderness Jeff , Rollins MaryClare , Jutila Mark , Pascual David 
Published: January 2023

Abstract
Pulmonary F. tularensis infections are highly lethal in untreated patients, and current antibiotic regimens are not always effective. Thus, we hypothesize that innate immunity augmentation with natural compounds could improve protective immunity to Francisella and complement antibiotic therapies. Screening of a natural compound library revealed a plant polysaccharide with the ability to activate human γδ T cells. The addition of this plant polysaccharide to both mock- and Francisella-infected murine macrophages enhanced surface expression of CD11b, CD40, CD80 and CD86 along with augmenting production of IL-6, TNF-α, and IL-1β. Plant polysaccharide treatment also augmented clearance of F. tularensis from infected murine macrophages, an effect that was time-, dose-, and nitric oxide-dependent, but independent of MyD88. In addition, this plant polysaccharide could enhance clearance of Francisella from infected primary human macrophages when co-cultured with autologous NK cells, which were found to have elevated expression of IFN-γ mRNA. Therefore, this plant polysaccharide holds potential as a therapeutic agonist that can enhance resistance to F. tularensis infection. This work supported by NIH U54AI-65357, P01AT-04986 and NIH Contract HHSN2662004000009/N01-AI40009.
A novel model to study lethal vs. non-lethal viral encephalitis (43.1)
Authors: Taylor Katherine , Kolokoltsova Olga , Borisevich Vika , Peng Bi-Hung , Smith Jennifer , Estes Mark , Yun Nadya , Poussard Allison , Paessler Slobodan 
Published: January 2023

Abstract
Venezuelan equine encephalitis virus (VEEV) generally causes a mild febrile illness; however, a subset of patients,primarily children,develops lethal encephalitis. The virus requires high level biocontainment (BSL3) limiting the use of many research tools. A model of VEEV-like encephalitis that can be utilized to determine the protective host response to disease development is needed to study the mechanisms of immunoprotection. We hypothesized that intranasal inoculation of TC83, an attenuated strain of VEEV,in α/B TCR KO mice would mimic VEEV encephalitis. Infected α/B TCR KO developed signs of illness including significant weight loss,as compared to controls,but all mice fully recovered from infection. Viral titers at the peak of illness reached surprisingly high levels in the brain (log 9- log 10). These levels were reduced (log 3- log 5). Surprisingly, similar low levels of virus were maintained indicating the ability of TC83 to persist in the brain. Visceral organs had low level of virus present during acute infection only. The reduction of infection occurred in the absence of T cells and detectable neutralizing antibody levels. Infection-induced transcriptomes in the brain of the murine host as well as cytokine protein levels demonstrated elevated levels of IL-12(p40), INF-β, MCP-1, MIP-1α, MIP-1β, and RANTES. TGF-β was below the limit of detection. This model represents a unique situation to study acute viral response and chronic viral persistence in the CNS.
IgD-bearing B cell populations in the channel catfish, Ictalurus punctatus (43.17)
Authors: Edholm Eva-Stina , Sahoo Manoranjan , Bengten Eva , Wilson Melanie 
Published: January 2023

Abstract
Channel catfish, Ictalurus punctatus, express two different IgD+ B cell populations. Catfish IgM+/IgD+ B cells are small and agranular, while IgM-/IgD+ B cells are larger and exhibit plasmablast morphology. The use of cell sorting, flow cytometry and RT-PCR demonstrated that IgD+ B cell expression varies between individual catfish. For example, some catfish have little to no IgD+ B cells in their peripheral blood leukocytes (PBL), while in others the IgM-/IgD+ B cell population can represent as much as 72%. This contrasts to the situation in mammals where IgM-/IgD+ B cells are rare. Also, transfection studies show IgD functions as a typical BCR since Igδ chains associate with accessory molecules CD79a and CD79b. Furthermore, IgM-/IgD+ B cells preferentially express IgL σ chains, while IgM+/IgD+ B cells can express any of the four catfish IgL isotypes. As assessed by 5'-RACE, all membrane IgD transcripts from sorted IgM-/IgD+ B cells contained viable VH rearrangements with no bias in family member usage. However, all secreted IgD transcripts were V-less and began with a leader sequence spliced to the Igδ CH1 domain and it is likely that these transcripts encode for the secreted form of IgD previously found in catfish serum. Importantly, the Igδ leader mediated IgD protein secretion when transfected into catfish B cells. This characterization of distinct IgM+/IgD+ and IgM-/IgD+ B cells in teleosts provides an important first step in understanding the evolution of IgD function.
Characterization of intestinal distension in ELT-2kd Caenorhabditis elegans upon infection with Pseudomonas aeruginosa (43.27)
Authors: Elliott Samantha , Sturgeon Craig , Montgomery Madeline 
Published: January 2023

Abstract
Caenorhabditis elegans has become a popular model for studying innate immunity. Recently, the transcription factor ELT-2, which is homologous to human GATA-4, -5 and -6, has been shown to play a role in the nematode immune response, along with its established role in intestinal development. One characteristic of ELT-2’s role in innate immunity is the accumulation of bacteria and distension of the intestinal lumen when ELT-2 is downregulated in the nematode by RNA interference. However, the mechanism of this distension remains unclear. In this study, we characterize the timeline of intestinal distension in ELT-2kd and ELT-7kd nematodes during Pseudomonas aeruginosa infection. We show that intestinal distension is seen in ELT-2kd but not ELT-7kd nematodes during P. aeruginosa infection. Significant distension in ELT-2kd nematodes is seen within 30 hours of pathogen exposure. A detailed comparison of this distension with survival of the nematodes on the pathogen will be presented. These data provide new insight into the role of ELT-2 in protecting C. elegans against pathogenic bacteria.
Evidence for NK cells in equine endometrial cups (43.29)
Authors: Noronha Leela , Huggler Kate , de Mestre Amanda , Antczak Douglas 
Published: January 2023

Abstract
Placentation during equine pregnancy is distinguished by a unique subset of trophoblast cells that invade the endometrium and form discrete structures termed the endometrial cups. Shortly after the trophoblasts invade, there is a dramatic infiltration of maternal leukocytes which accumulate around the cups. Our lab has previously characterized the infiltrating leukocytes as primarily CD3+ cells with substantial CD4+ and CD8+ subpopulations. Here, we identify expression of the NK cell marker NKp46 in peripheral blood mononuclear cells (PBMC) and endometrial cup lymphocytes (ECL). PCR primers were developed to detect the equine homolog of NKp46 and expression was detected in resting and stimulated lymphocytes using standard PCR. Quantitative real-time PCR primers and standards were used to quantitate expression in CD3+ and CD3- sorted lymphocytes. NKp46 gene expression in CD3- lymphocytes was 10-fold higher than in CD3+ cells. Levels comparable to CD3-depleted lymphocytes were detected in frozen tissue sections of endometrial cups. The highest levels of expression were detected in leukocytes isolated from the endometrium surrounding the cups of five mares during early pregnancy (days 43-46). NKp46 expression levels were 7-43 fold higher in ECL compared to paired PBMC (p=0.04). Coincident CD3γ expression was lower in all ECL compared to paired PBMC (p=0.03). These data provide the first evidence for the presence of NK cells in the equine endometrium during pregnancy.
The puzzle of TIR domain-containing proteins in bacteria (43.3)
Authors: Zhang Qing , Zmasek Christian , Cai Xiaohui , Godzik Adam 
Published: January 2023

Abstract
Toll/interleukin-1 receptor (TIR) domain-containing proteins play important roles in defense against pathogens in both animals and plants, connecting the immunity signaling pathways via a chain of specific protein-protein interactions. Among them is SARM, the only TIR domain-containing adaptor that can negatively regulate TLR signaling. By extensive phylogenetic analysis, we show here that SARM clusters with bacterial TIR domains, suggesting a relatively recent lateral gene transfer from bacteria to animals. We also show evidence of several additional, independent transfer events, none of which, however, survived in vertebrates. TIR domain-containing proteins had been characterized in bacterial pathogens, where they were shown to represent a new class of virulence factors that can suppress animal Toll-like receptor (TLR) dependent host defenses. An evolutionary relationship between the animal SARM adaptor and bacterial proteins with TIR domains illustrates the possible role that bacterial TIR-containing proteins play in regulating eukaryotic immune responses and how this mechanism was possibly adapted by the eukaryotes themselves.