bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential role of B7 co-stimulation on B cells and dendritic cells for Th1 and Tfh differentiation (LYM8P.631)
Authors: Kamphorst Alice , Watanabe Masashi , Araki Koichi , Rasheed Mohammed Ata Ur , Davis Carl , Yang Shu , Konieczny Bogumila , Hodes Richard , Ahmed Rafi 
Published: January 2023

Abstract
Upon activation CD4 T cells differentiate into different subsets that have distinct functions in the immune response. Antigen presentation in the presence of co-stimulation and cytokines is required for optimal CD4 T cell activation and differentiation. Cytokines play a well-described crucial role driving CD4 T cell differentiation, but the role of different antigen presenting cells and co-stimulation remains relatively unexplored. To address this question we developed mice that lack B7-1 expression on B cells or on dendritic cells (DCs), on a B7-2 deficient background. CD4 differentiation was studied in the context of acute lymphocytic choriomeningitis virus (LCMV) infection. We find that mice lacking B7-1 on DCs have a profound defect on virus-specific CD4 T cell expansion that affects Th1 and Tfh numbers, but with the most drastic reduction in Th1 differentiation. In contrast, mice lacking B7-1 on B cells have similar numbers of LCMV-specific CD4 T cells as control mice. However, even though CXCR5 expressing LCMV-specific CD4 T cells numbers appear unaffected by B7-1 deficiency on B cells, there was a reduction in cells expressing high levels of CXCR5, PD-1 and Bcl-6 and a profound defect in LCMV-specific long lived plasma cells and antibodies. We conclude that CD4 T cell differentiation requires cell-type specific co-stimulation, and co-stimulation by B cells is essential to obtain functional Tfh and long-term humoral responses after acute viral infection.
STAT4 promotes atherosclerosis by supporting Tfh and plasma B cell development, T cell activation and CD11b+ cell accumulation in the aortic wall (LYM8P.632)
Authors: Taghavie-Moghadam Paresa , Kaplan Mark , Nadler Jerry , Galkina Elena 
Published: January 2023

Abstract
Atherosclerosis is an inflammatory disease of medium and large size arteries. Signal transducer and activator of transcription 4 (STAT4) is a transcription factor that supports the generation of cells with features of both follicular helper T cells (Tfh) and T helper 1 (Th1) cells. To date, the role of Stat-4 in atherosclerosis and the induction of Tfh cells in this disease has not been defined. To investigate the role of STAT4 in atherogenesis, we generated Stat-4-deficient low density lipoprotein-deficient (Stat4-/-Ldlr-/-) mice. Stat4 deficiency resulted in a significant reduction in atherosclerotic plaque burden within the aortas of Stat4-/-Ldlr-/- mice fed a high fat/high carbohydrate diet with added cholesterol (DDC) diet for 16 weeks compared to age and diet-matched Ldlr-/- control mice (p&lt;0.01). Next we examined spleens and peripheral lymph nodes (PLNs) of Stat4-/-Ldlr-/ mice and found decreased number of CD19+ B cells (p&lt;0.0001) and CD3+ T cells (p&lt;0.05). Interestingly, the number of Tfh cells and plasma B cells (p&lt;0.003) was also diminished in and spleens of Stat4-/-Ldlr-/- mice compared to Ldlr-/- mice. A significant reduction in CD11b+CD11c- cells and MHCII expression was detected in the aortas of Stat4-/-Ldlr-/- vs Ldlr-/- mice. Thus, the atherogenic effects of STAT4 are, at least partially, due to the modulation of the immune response via alterations of Tfh-dependent humoral response. Supported by R01 HL112605 and Suppl.Grant 02S1.
Utilizing CX3CR1GFP/PGRPdsRed reporter mice to monitor myeloid and granulocyte responses during helminth infection (MPF6P.652)
Authors: Barnes Mark , Jang Jessica , Wang Spencer , Lo David , Nair Meera 
Published: January 2023

Abstract
CX3CR1GFP/PGRPdsRed reporter mice have previously been used to monitor trafficking of monocytes and neutrophils, respectively. With this new tool, we examined myeloid cell and neutrophil behavior during murine infection with the helminth, Nippostrongylus brasiliensis (Nb). Nb acutely infects the lungs leading to significant infiltration of PGRPdsRed neutrophils and CX3CR1GFP monocytes compared to naïve mice. Using ex vivo time-lapse confocal microscopy, we discovered that Nb infection increased chemotaxis of CX3CR1GFP monocytes and PGRPdsRed neutrophils. Because CX3CR1GFP expression is a loss of function knock-in mutation, we tested the function of CX3CR1 in the immune response to Nb. After inoculation with infective larvae, CX3CR1GFP mice were less susceptible to infection compared to wild-type mice and had lower worm counts and parasite eggs in the feces. Additionally, ATP cell viability assay revealed that worms recovered from reporter mice were less viable than worms isolated from wild-type mice. Taken together, CX3CR1GFP/PGRPdsRed mice make it possible to monitor myeloid cell and neutrophil behavior, and reveal a previously unrecognized role for CX3CR1 in impairing Nb expulsion.
The fungal secondary metabolite alternariol and Alternaria induced immunity (MPF6P.659)
Authors: Grover Shivani , Howard Brad , Lawrence Christopher 
Published: January 2023

Abstract
Sensitivity to the airborne fungus Alternaria alternata (common mold) is believed to be a common cause of allergic asthma. Epidemiological studies worldwide indicate that Alternaria sensitivity is closely linked with the development and exacerbation of allergic airway disorders such as asthma, allergic rhinitis, and chronic rhinosinusitis. Therapies are limited by the lack of knowledge about the role of individual fungal gene products in airway responses. The A. alternata mycotoxin alternariol is a genotoxic and cytotoxic molecule and a major contaminant of most food, grains and feed products. We hereby present a study where we explored the hypothesis of alternariol having immune-modulatory properties. It led us to the discovery that alternariol is strongly anti-inflammatory. We have investigated alternariol’s dynamic interplay between innate immunity and human bronchoalveolar epithelial cells. Immune assays have provided the key doses needed to suppress LPS-induced inflammation. We have also profiled the response of mutant fungal spores that no longer produce alternariol with normal wildtype spores on lung epithelium. This model has also been used to investigate alternariol’s mechanism of action in relation to aryl hydrocarbon receptor. Greater understanding of the role of alternariol in allergic asthma may lead to improved treatment strategies as well as a potential drug target for inflammatory syndromes.
Comparison of culture-positive and culture-negative bronchoalveolar lavage from mechanically ventilated trauma patients by next-generation sequencing and cytokine analysis (MPF6P.661)
Authors: Smith Ashley , Zhang Yan , Huebinger Ryan , Ireland Sara , Monson Nancy , Allen Michael 
Published: January 2023

Abstract
Mechanically ventilated trauma patients are at high risk for ventilator-associated pneumonia (VAP). VAP diagnosis relies on several clinical factors including the identification of a specific pathogen by culture-dependent techniques. Often, patients exhibit signs of VAP, yet the hospital lab is unable to culture a pathogen from a bronchoalveolar lavage (BAL) sample. Here, culture-positive and -negative hospital results were tested again by Sanger and next-generation sequencing (NGS) on the Ion Torrent PGM. Sample cytokine levels were determined using a Bio-Plex Pro Human Th17 cytokine panel. No significant difference was seen between the identification methods in culture-positive BAL. However, NGS analysis of culture-negative BAL identified hundreds of bacterial genera, including a group of patients that exhibited similar bacterial composition, diversity, and abundance. This group was significantly different from other culture-negative BAL that were dominated by one or two suspected pathogens. Culture-negative BAL contained significantly less IL-1β, IL-6 and TNF-α than culture-positive BAL. NGS is a valuable method for pathogen identification, particularly for difficult to culture BAL. Culture-positive BAL exhibit less bacterial diversity and increased cytokine production than culture-negative BAL. The grouping of culture-negative BAL with similar characteristics may denote a core lung microbiome.
Immune sensing of fungal cell wall carbohydrates programs immunity to A. fumigatus infection: role of γδ T cells. (MPF6P.662)
Authors: Amarsaikhan Nansalmaa , O`Dea Evan , Tsoggerel Angar , Li Hongtao , Templeton Steven 
Published: January 2023

Abstract
The human fungal pathogen Aspergillus fumigatus is associated with allergic sensitization and invasive infection in susceptible individuals. How the combined recognition of fungal molecular patterns programs host adaptive immunity is not well understood. Previously, we observed that fungal chitin promotes Th2-skewed immunity and eosinophil recruitment that proved detrimental to fungal clearance in invasive infection. In this study, we further characterized the role of early cytokine and effector cells in chitin derived eosinophil activation. We observed that single aspiration of a high-chitin isolate (Af5517) resulted in a marked increase in early transcription of IL-17A. Furthermore, eosinophil recruitment was not increased in RAG1-/- mice, suggesting that γδ T cells are required for early recognition of conidia-associated chitin. Although IL-17A was not required, the absence of γδ T cells (known to be potent sources of innate IL-17A) resulted in a significant decrease in eosinophil recruitment after single and multiple aspirations of Af5517. Also, fungal strains displaying chitin increased exposure or manipulating cell surface carbohydrate ratio by blockage of β-glucan recognition on receptor level resulted in increased airway eosinophil recruitment suggesting that relative high chitin/low β-glucan recognition leads to increased eosinophil recruitment and Th2 responses that are promoted by early responses of γδ T cells.
Killer lymphocytes deploy granulysin and granzymes to induce oxidative death of parasites (MPF7P.712)
Authors: Dotiwala Farokh 
Published: January 2023

Abstract
Killer lymphocytes protect against parasites, but what happens to intracellular parasites when the infected host cell is recognized is unknown. Here we show that the killer cell antimicrobial peptide granulysin delivers death-inducing granzymes into Trypanosoma cruzi, Toxoplasma gondii, and Leishmania major, where they generate superoxide, disrupt the mitochondrial potential and induce death, which shares features of granzyme-mediated bacterial death and mammalian apoptosis. Granzyme B also cleaves key oxidative defense enzymes in T. cruzi. Parasite killing depends on perforin to deliver granulysin and granzymes into the infected host cell, is blocked by superoxide scavengers and by overexpressing oxidative defense enzymes. T. cruzi infection was compared in wild-type mice that lack granulysin and GNLY-transgenic mice. GNLY-transgenic mice survived infection that was lethal to most wild-type mice. In vivo protection required perforin and was mediated by CD8+ cytotoxic T lymphocytes.
Role of IL-33 in chronic pulmonary mycobacterial infection (MPF7P.705)
Authors: Umemura Masayuki , Fukui Masayuki , Yamasaki Masatoshi , Fukui Chiho , Nakae Susumu , Matsuzaki Goro 
Published: January 2023

Abstract
IL-33 is a recently identified IL-1 family cytokine that promotes type 2 immune responses by signaling through the receptor complex consisted of ST2 and IL-1RAcP. Recent study using ST2 KO mice showed that IL-33 mediated signaling is required for the development of innate and adaptive immune responses against pulmonary Cryptococcus neoformans infection, suggesting involvement of IL-33/IL33R system in pulmonary cell-mediated immunity. In contrast, the ST2 KO mice showed normal protective immunity against pulmonary Mycobacterium tuberculosis (Mtb) infection. In this study, we analyzed role of IL-33 in host defense against chronically infected Mtb using IL-33 KO mice. The survival rate of the IL-33 KO mice was similar to that of the wild-type (WT) mice during 1 year observation period. Bacterial burdens of various organs of the IL-33 KO mice on the day 120 were nearly the same as that of the WT mice. In the infected lungs, inflammatory cytokine such as IFN-γ, TNF-α and IL-6, production of the IL-33 KO mice were similar to that of the WT mice. This result indicated that the generation of Th1 cells was not affected in the IL-33 KO mice infected with Mtb. Furthermore, the size of granulomatous lesionss in the lungs of the IL-33 KO mice were similar in comparison to the granulomas that of the WT mice on day 250 of infection. These data strongly support the notion that the lack of IL-33 neither suppress nor enhances protective immunity in the lung after mycobacterial infection.
CD8 T cell mediated disruption of tight junctions is associated with vascular permeability in vital brain regions during experimental cerebral malaria (MPF7P.708)
Authors: Huggins Matthew , Jin Fang , Johnson Aaron 
Published: January 2023

Abstract
One of the most severe complications of Plasmodium falciparum infection in humans is cerebral malaria. Cerebral malaria causes coma, neurological deficits, and potentially death. The disease is characterized by blood-brain barrier (BBB) disruption leading to vascular permeability. In this study, we investigated cerebral endothelial cell tight junction protein alterations and BBB breakdown in the Plasmodium berghei ANKA (PbA) model of experimental cerebral malaria. PbA infected C57BL/6 mice displayed significant areas of vascular leakage within the central nervous system at six days post infection. Regions of permeability co-localized with disruption of the BBB tight junction proteins claudin-5 and occludin on microvasculature as shown using confocal microscopy. Additionally, 3D MRI analysis revealed that PbA infected mice exhibited vascular leakage specific to the hypothalamus, thalamus, and brain stem. In contrast, PbA infected perforin deficient mice retained tight junction integrity and displayed significantly reduced vascular leakage. We propose that CD8 T cells initiate vascular permeability through disruption of cerebral endothelial cell tight junctions. In turn, the resulting imbalance of homeostasis in vital brain regions likely contributes to the pathology and morbidity associated with PbA infection.
Serum-derived bovine immunoglobulin increases peripheral and mucosal CD4 T cell count (MUC8P.736)
Authors: Asmuth David , Somsouk Ma , Min Ma Zhong , Hunt Peter , Miller Christopher , Dong Li Xiao , Hinkle John , Shaw Audrey , Weaver Eric , Klein Gerald 
Published: January 2023

Abstract
A multi-center trial in HIV-enteropathy was conducted to evaluate the impact of serum-derived bovine immunoglobulin (SBI) on markers of peripheral and mucosal immunity as previously reported. Participants (pts) with HIV enteropathy were randomized to SBI 2.5 vs 5.0 g BID or placebo (PBO) during a 4-wk lead-in phase followed by SBI 2.5 vs 5.0 g BID for 20 wks. 103 pts were enrolled with a mean duration of HIV, ART, and enteropathy over 15, 5 and 5 years, respectively. While there was no evidence for a median change in peripheral CD4 counts in all pts from baseline to wk 24 (681 to 661 cells/mL), significant increases were observed among pts in the lowest quartile (n=24)(311 to 366 cells/mL, p=0.002). In this subgroup the SBI pts had increased CD4 counts at wk 4 vs PBO pts (median +42 vs ‑16 cells/mL, p=0.02) which was maintained through wk 24. The mean plasma zonulin levels increased from 358(±317) to 812(±423) ng/mL (p&lt;0.001) for pts receiving SBI through 24 weeks. Duodenal CD4 densities increased from 217 to 329 cells/mm2 (median increase of 145 cells/mm2 [p=0.02]) in biopsies obtained from 8 pts, confirming earlier findings. Duodenal crypt cells expressing Ki67 decreased in 6/7 pts from 41% to 24% (p=0.08) which correlated with the decreased number of Paneth cells per crypt (p=0.048). SBI may be a novel therapy to restore mucosal immunity and impact systemic immune reconstitution among pts who have not achieved normal CD4 counts despite prolonged suppressive ART.
TRAF6 expression in dendritic cells is essential for tolerance to dietary antigens (MUC8P.723)
Authors: Han Daehee , Walsh Matthew , Choi Yongwon , Surh Charles 
Published: January 2023

Abstract
TRAF6 is critical for Toll-like receptor (TLR)-mediated activation of dendritic cells (DCs). Recently, by studying mice DC-specific deletion of TRAF6 (TRAF6ΔDC) we have reported that TRAF6 expression in DCs is important to prevent a spontaneous Th2-associated gut inflammatory disease. We also found amelioration of TRAF6ΔDC disease by treatment with broad-spectrum antibiotics, suggesting a role for commensal microbiota. To formally demonstrate an involvement of commensal microbiota, we have now generated TRAF6ΔDC bone marrow chimeras under germ-free (GF) conditions. Unexpectedly, the Th2-associated disease in GF TRAF6ΔDC chimeras was exacerbated compared with TRAF6ΔDC chimeras generated under conventional conditions, indicating a beneficial role of commensal microbiota. Moreover, treatment of GF TRAF6ΔDC chimeras with broad-spectrum antibiotics also ameliorated the Th2-associated disease, suggesting a previously unrealized direct immunomodulating effect of antibiotics. Finally, to test whether the Th2-associate disease is driven by dietary antigens (Ags), we established TRAF6ΔDC bone marrow chimeras in “Ag-free” mice, in which GF mice are raised with a chemically-defined elemental diet devoid of macromolecules. Strikingly, the induction of a spontaneous intestinal Th2-associated inflammatory disease was dramatically averted in “Ag-free” TRAF6ΔDC chimeras, indicating that TRAF6 expression in DCs is essential to establish and/or maintain oral tolerance to dietary Ags.
A defect in a small-intestinal lymphoid structure affects colonic B cell development (MUC8P.726)
Authors: Surana Neil , Kasper Dennis 
Published: January 2023

Abstract
Peyer’s patches (PPs) are small-intestinal secondary lymphoid organs that represent an important inductive site for intestinal immunity. In this study, we prevented formation of PPs to examine its influence on intestinal immunity. Pregnant dams were injected at E14 with an IL-7Rα antibody, resulting in inhibition of PP formation in the pups. Flow cytometric analysis revealed no change in the numbers of immune cells in the spleen, lymph nodes, or small-intestinal lamina propria (SI LP). Surprisingly, the colon of PP-deficient mice was lymphopenic, with a specific decrease in CD19+ B cells, including colonic plasmablasts. We extensively looked for other defects (e.g., lymphoid structures, changes in cecal or peritoneal B cells, microbiota-related effects) that might explain this colonic phenotype, but everything else was normal. In control animals, the number of B cells present in PPs was strongly correlated to the number of B cells in the colon but not the SI LP. Moreover, if pregnant dams were injected with the IL-7Rα antibody at E18, the resulting pups had normal-appearing PPs and the normal number of colonic B cells. Interestingly, PP-deficient mice have more severe disease in infectious and chemically induced models of colitis, demonstrating that these colonic B cells are functionally important. Taken together, our data strongly suggest that a portion of colonic B cells is regulated by PPs, indicating a link between the small- and large-intestinal immune systems.
Ocular microflora modulates IL-17 and neutrophil recruitment within the conjunctiva associated lymphoid tissue (MUC9P.739)
Authors: St. Leger Anthony , Caspi Rachel 
Published: January 2023

Abstract
Previous studies have suggested a critical role for the functionality of conjunctiva‑associated lymphoid tissue (CALT), a mucosal immune tissue of the ocular surface, to maintain anterior ocular health. In this study, we developed a working animal model to study the functional properties of CALT in WT B6 and interleukin (IL)-22 KO mice, which are known to have impaired barrier function at gut mucosal surfaces. Aged IL-22 KO mice spontaneously developed CALT neutrophilia resulting in opacification of the cornea (keratitis). Neutrophilia in the CALT depended on in situ production of IL-17A/F, and was significantly reduced 48 hours after a single subconjunctival injection of αIL-17A/F. Innate lymphoid cells (ILCs) as well as αβ and γδ T cells isolated from CALT produced IL-17 in response to IL-1β made by activated CD11b+ dendritic cells, suggesting a role for normal ocular microflora in modulating mucosal immune responses at the ocular surface. Indeed, wild type mice treated with topical or oral antibiotics as well as germfree mice had reduced IL-17 and neutrophils in CALT. Our data uncover an interdependence between the CALT and normal ocular microflora for regulating mucosal immune function at the ocular surface and demonstrate its importance for maintaining long-term ocular surface homeostasis.
Pentobra: A novel antibiotic with potent antimicrobial activity against Propionibacterium acnes (TECH2P.901)
Authors: Agak George , Schmidt Nathan , Deshayes Stephanie , Yu Yang , Blacker Alyssa , Champer Jackson , Kao Stephanie , Xian Wujing , Kasko Andrea , Kim Jenny , Wong Gerard 
Published: January 2023

Abstract
Although antibiotics are a common form of treatment against acne, the difficulties inherent to effective antimicrobial penetration in sebum and selective antimicrobial action in skin are recently compounded by increasing resistance of Propionibacterium acnes clinical isolates. To address these problems, we engineered Pentobra, a peptide-aminoglycoside molecule which has multiple mechanisms of antibacterial action, and investigated whether it can be a potential candidate for the treatment of acne. Pentobra combines the potent ribosomal activity of aminoglycosides with the bacteria-selective membrane-permeabilizing abilities of antimicrobial peptides. Pentobra demonstrated potent and selective killing of P. acnes, but not against human skin cells. In direct comparison, Pentobra demonstrated bactericidal activity and drastically outperformed free tobramycin (by 5-7 logs) against multiple P. acnes strains. Moreover, EM studies showed that Pentobra also had robust membrane activity, as treatment with Pentobra killed P. acnes cells. Pentobra may also have potential anti-inflammatory effects. Importantly, the killing activity was maintained in sebaceous environments as Pentobra was bactericidal against clinical isolates in microcomedone extracts isolated from human donors. Our work demonstrates that equipping aminoglycosides with selective membrane activity is a viable approach for developing new antibiotics against P. acnes that are effective in cutaneous environments.