bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wnt signaling pathway functionally reprograms human virus-specific CD8 T cells (VAC4P.1065)
Authors: Sung Bo-Yi , Chiu Yen-Ling , Schneck Jonathan 
Published: January 2023

Abstract
Polyfunctionality, a single T cell producing a set of different effector molecules, is a hallmark of protective immunity against infection and tumor, but the molecular pathways governing the polyfunction T cells were not well known. In our lab, we found that memory CD8 T cells treated with TWS119, a Wnt pathway activator, increased highly polyfunctional memory T cells formation during expansion. The treatment of TWS119 enhanced CD62L+, CD28+ and KLRG1- central memory T cell phenotype. We further analyzed the impact of Wnt activation on influenza virus or CMV(cytomegalovirus) antigen-specific stimulation, and found TWS119 also improved the polyfunctionality. Especially in CMV-specific T cells, terminal differentiated non-polyfunctional population, Wnt signaling reversed their non polyfunctional state. Wnt-activated T cells were capable of superior homeostatic proliferation and expressed more anti-apoptotic molecules. Mechanistically, RNA microarray analysis revealed that Wnt activation led the gene expression profile correlated with stem-cell specific gene expression pattern. Our findings provided the evidence that non-polyfunctional antigen-specific human CD8 T cells response can be pharmacologically reprogrammed and have important translational implications for immunotherapy against chronic viral infections and malignancies.
Skin dendritic cells induce follicular helper T cells and protective humoral immune responses (VAC4P.1101)
Authors: Yao Chen , Zurawski Sandra , Jarrett Elizabeth , chicoine brian , Crabtree Juliet , Peterson Erik , Zurawski Gerard , Kaplan Daniel , Igyarto Botond 
Published: January 2023

Abstract
Skin-resident dendritic cells (DC) play a crucial role in initiation of adaptive immune responses against cutaneous pathogens as well as in the maintenance of peripheral tolerance. Recent studies have suggested that steady-state Langerhans cells (LC) induce regulatory T cells against self-antigens. However, the immune response induced by skin DC against foreign antigen in the absence of adjuvants has not been addressed. Here we report that, using anti-huLangerin/ muLangerin antibodies, we could specifically target antigens to LC or CD103+ dermal DC. Presentation of the foreign peptide 2W1S by either LC or CD103+ dDC was sufficient for expansion of naïve CD4+ T cells and induction of T follicular helper cell (Tfh) differentiation. Notably, topical application of peptide or protein also efficiently induced Tfh. The expansion of Tfh specific to foreign peptide was accompanied by activation and expansion of antigen-specific B cells and the development of a robust antibody response that provided systemic protection against influenza infection. This study not only reveals a major unappreciated function of skin DC in humoral response, but also provides insight into DC-targeted vaccine design.
Measuring the properties of different forms of keyhole limpet hemocyan reveals important differences (VAC5P.1116)
Authors: Bi Shuguang , Milbrandt Laura , Brisson Catherine 
Published: January 2023

Abstract
KLH can exist as cylinders composed of 20 copies (didecamer) of subunits, or as separate subunits. It is a well-established immune stimulant and vaccine component. However, literature reports cite dramatically different immune responses to different preparations of KLH. We are developing functional assays to investigate the immunogenicity of different forms and preparations of KLH with the goal of improving the predictive outcome of its use as vaccine carrier or diagnostic agent for both research and clinical studies. Dendritic cells (DCs) derived from mouse bone marrow mononuclear cells, human PBMC, mouse DC line JAWSII, as well as human leukemia lines THP-1 and KG-1, were treated with different forms of KLH. To compare the efficiency of DCs to stimulate KLH-specific adaptive immune responses, KLH treated DCs were used to activate T cells extracted from spleens of mice that were immunized with KLH. DC antigen uptake efficiency, DC maturation, T cell proliferation and cytokine secretion were compared. Ovalbumin was conjugated to different forms of KLH. DCs derived from mouse bone marrow mononuclear cells were treated with the KLH-Ovalbumin conjugates for antigen uptake efficiency and ovalbumin-specific T cell activation studies. We found that didecameric KLH and subunit KLH have significantly different properties. We report here the results of these studies which suggest the need for methods to identify appropriate forms of KLH when used as hapten carrier or immunogen.
Immunostimulatory activity of indium phosphide quantum dots in vitro and in vivo (VAC5P.1128)
Authors: Lyle Christopher , Byrne Kristen , Falcon Daniel , Dienglewicz Robert , Jang Hyeonmin , Aguilar Zoraida , Erf Gisela 
Published: January 2023

Abstract
Quantum dot nanoparticles (QDs) have shown increasing promise in biological applications including enhanced immunomodulatory effects that may be leveraged as vaccine adjuvants. While cadmium selenium based QDs were shown to have toxic effects in vivo, recent studies have shown that indium phosphide QDs offer a safer alternative. The objective of this study was to examine the bioactivity of 7 nm InP/ZnS QDs (670 nm emission) in vitro and in vivo in the avian model. In vitro studies on the effects of QDs on chicken macrophages revealed uptake of QDs within 45 min with minimal nitric oxide production and cytotoxicity. To monitor in vivo effects of QDs, we utilized the pulp (dermis) of growing feathers (GF) as a test-tissue. For this, 10 μL of QDs (4, 1, or 0.25 μM) were injected into the pulp of 20 GF/chicken (n = 4/treatment). GF were collected 0.25, 1, 2, 3, 5, and 7 days post-injection for cell population analysis of infiltrating leukocytes by flow cytometry and immunohistochemical staining of frozen sections for localization of leukocytes and QDs. Leukocyte infiltration was observed by 6 h. Leukocyte profiles were both time and dose dependent and inflammatory in nature. Combined immunohistochemical and fluorescence studies of frozen GF sections confirmed the presence of QDs and immune cells. Gene-expression (qRT-PCR) analyses are underway. To our knowledge this is the first study to assess in vivo immune activities in response to InP/ZnS QDs injected into a complex tissue.
Immune response induced by vaccination with non-replicative type I strain of Toxoplasma gondii (CPS-1) induces more tetramer specific CD8 T cells with central memory phenotype. (VAC5P.1117)
Authors: Dominguez Mariana , Hwang Sujin , Nixon Douglas , Moretto Magali , Khan Imtiaz 
Published: January 2023

Abstract
Role of CD8 T cells in immunoprotection against Toxoplasma gondii infection is well established. However, in an encephalitis model, CD8 immunity is functionally impaired (immune exhaustion), leading to reactivation of latent infection. Studies from our laboratory have reported that functional defect during chronic infection is primarily exhibited by memory subset of CD8 T cells. Thus restoration of dysfunctional CD8 response may be critical for maintaining the chronicity and preventing the reactivation of latent infection. As a first step we evaluated and compared the antigen-specific CD8 T cell response induced by vaccination with the non-replicative type I strain of Toxoplasma gondii (which efficiently controls per-oral infection with type II strain) to the one induced during chronic infection. While type II strain induced a stronger SLEC (short lived effector CD8 cell) response as compared to vaccine strain in all the tissues tested, MPEC (memory precursor effector cell) response with both the strains was similar. However, interestingly the frequency of central memory cells subset (CD127+CD62Lhigh) in the vaccinated mice was significantly higher as compared to those receiving type II infection. These findings suggest that the development of inadequate central memory CD8 response may be an important defect responsible for reactivation of infection in mice susceptible to toxoplasmic encephalitis.
Passive immunization via neutralizing scFv-Mab to specific antigen of Aggregatibacter actinomycetemcomitans ameliorates periodontal infection and destruction in vivo (VAC5P.1120)
Authors: Teng Andy , Liu Yen Chun 
Published: January 2023

Abstract
Aggregatibacter actinomycetemcomitans-Aa, a G(-) anaerobe, is involved in medical/dental infection, i.e., aggressive periodontitis, & systemic disorders. To explore anti-bacterial immunity & therapeutics, its genomic library was screened by expression-cloning using disease-associated CD4+T-cells of HuPBL- NOD/SCID mice. Such cloning yielded one novel gene, designated cagE-homologue, encoding a bacterial type-IV secretion system homologous to Helicobacter pylori cagE & Agrobacterium tumefaciens virB4. We showed that: i) Aa-CagE induced apoptosis of targets, based on biochemical & genetic studies; ii) anti-CagE IgG-response was significantly correlated with disease progression. By CagE immunization in HuPBL-SCID mice and the recombinatorial phage-display library, we screened to develop therapeutics for Aa. The screening yielded human sc-Fv-Mabs to CagE (CagE-scFv-Mabs), as confirmed by binding assay & sequencing. To this end, our latest studies showed that human CagE-scFv-Mabs were manifested by: i) high binding activity (&gt;108~9M-1); ii) strong neutralizing capability by inhibiting CagE-induced caspase3-mediated apoptosis (&gt;80%); iii) possessing anti-toxin-like Ig-CDR sequences; iv) significantly reduced Aa colonization in biofilm and reduced alveolar bone loss in mice. It is concluded that CagE-scFv-Mabs capable of inhibiting apoptosis, Aa colonization and bone destruction via immunization exhibit the potential to ameliorate periodontal & medical infections associated with Aa.
De novo detection and HLA-association of public T cell responses to Cytomegalovirus using high-throughput immune repertoire sequencing (VIR1P.1134)
Authors: Emerson Ryan , DeWitt William , Desmarais Cindy , Rieder Mark , Carlson Christopher , Gravley Jenna , Hansen John , Robins Harlan 
Published: January 2023

Abstract
We investigated the public T cell response to cytomegalovirus by sequencing rearranged T cell receptors (TCRs) in 640 subjects (287 with & 353 without CMV). We performed an experiment similar to a GWAS study, assessing the concordance of millions of unique TCRs with CMV serostatus, looking for significant associations. With CMV serostatus and TCR sequencing data, we identify 142 public T cell responses to CMV (each with p ≤ 1.0 x 10-4; FDR ≈ 0.20). Using this method to identify public clones, we predict CMV serostatus in a leave-one-out cross-validation experiment with a diagnostic odds ratio of 66. Using HLA typing, we then estimate the HLA-association of each public CMV clone by assessing the over-representation of particular HLA types in associated subjects. Of 142 CMV public clones, 26 were HLA-associated at p &lt; 10-6; no clones were significantly associated with multiple HLA alleles. When comparing our results to the literature, we find substantial concordance; most previously-reported public CMV clones are seen in our data, though only 2 are significantly associated with CMV serostatus in this cohort; both were significantly HLA-associated and in both cases the associated allele confirms previous findings. We demonstrate the validity of association studies using immunosequencing for detection and HLA-association of public T cell responses to infection, and report that assessing the presence of public T cell responses can serve as a powerful diagnostic classifier.
Age-dependent defects in the draining lymph node and naïve CD4+ T cell trafficking impair adaptive immunity and control of virus infection (VIR1P.1137)
Authors: Richner Justin , Gmyrek Grzegorz , Miller Mark , Diamond Michael 
Published: January 2023

Abstract
Although adaptive B and T cell responses decline with age, the basis for impaired immunity of the elderly against viruses remains uncertain. Herein, in the context of infection with West Nile virus (WNV), we identify new mechanisms for compromised adaptive immunity that occurs with aging. Old mice had blunted humoral immune responses to WNV, increased viral burden, and enhanced mortality. This decline in immunity and enhanced vulnerability to infection was associated with decreased trafficking capacity of naïve CD4+ T cells but not B cells from old mice, which manifested as impaired T cell diapedesis at high endothelial venules and reduced cell motility within draining lymph nodes (DLN) as judged by intravital microscopy, as well as delayed germinal center formation. Additionally, immune cell accumulation in the DLN after virus infection or antigen-adjuvant administration was diminished more generally in old mice and associated with a separate aging-related defect in local cytokine and chemokine production. Our results support a model in which age-dependent cell-intrinsic and cell-extrinsic defects result in delayed immune cell recruitment and antigen recognition in the DLN, which compromises induction of adaptive immune responses and contributes to the susceptibility of old animals to acute viral infections, and likely impaired vaccine responses.
T cell expression of the histone demethylase UTX promotes clearance of a persistent virus infection by modulating Tfh cell differentiation (VIR1P.1155)
Authors: Cook Kevin , Shpargel Karl , Starmer Joshua , Whitfield-Larry Fatima , Conley Bridget , Allard Denise , Magnuson Terry , Su Maureen , Whitmire Jason 
Published: January 2023

Abstract
T cell differentiation and memory formation are impacted by epigenetic changes that modulate nucleosome structure to regulate transcription factor accessibility. The enzymes and specific targets that mediate these processes within T cells are not clear. We show that UTX, a histone H3 lysine 27 (H3K27) demethylase, promotes the formation of the CD4+ T follicular helper cell (Tfh) phenotype during a chronic virus infection. Mice with T cell specific UTX deletion had defects in Tfh cell generation and function that resulted in reduced germinal center responses and virus-specific immunoglobulin production. Furthermore, clearance of the chronic virus infection was specifically dependent on T cell expression of UTX. H3K27me3-ChIP-sequencing and RNA expression analysis revealed a subset of genes that were specifically regulated by UTX via H3K27 demethylation. This group included IL-6Ra, a known regulator of Tfh responses, as well as other genes, which are potentially novel Tfh effector genes. Thus, we identify a critical link between UTX-dependent H3K27 demethylase activity in T cells and immunity to infection.
Virus-infected human mast cells enhance Natural Killer cell functions (VIR1P.1160)
Authors: Portales-Cervantes Liliana , Haidl Ian , Lee Patrick , Marshall Jean 
Published: January 2023

Abstract
Mast cells are widely distributed throughout vascularised tissues. At mucosal surfaces they play important roles in host defence. Human mast cells produce chemokines, such as CXCL8, that selectively recruit Natural Killer (NK) cells in models of viral infection. However, the ability of mast cells to enhance NK cell effector functions has not been previously examined. Primary human mast cells were infected with reovirus and derived mast cell products were used for stimulation of human NK cells. Mast cell products induced expression of the activation marker CD69 (n=7; p&lt;0.001), the cytotoxicity-related genes PRF1 (n=6; p&lt;0.01) and TIA-1 (n=5; p&lt;0.05), and enhanced NK cell cytotoxic activity against K562 cells (n=6; p&lt;0.01). Interferon-γ was produced by NK cells treated with virus-induced mast cell mediators in the presence of IL-18 (n=7; p&lt;0.001). In vivo, reovirus-infected human mast cells induced a 7-fold increase in recruitment and activated murine NK cells (42.3% CD69+ vs 5.8% CD69+ cells) in comparison to uninfected mast cells in a subcutaneous matrigel model (n=9; p&lt;0.05). Soluble products of reovirus-infected mast cells included IL-10, type I and type III interferons. Blockade of type I interferon receptors revealed that they were important for mast cell-mediated NK cell activation. Our data define a novel mast cell-NK cell immune axis in human host defense against viral infection, which could be rapidly induced prior to the generation of acquired immunity.
Immune restoration, activation and viral reservoirs in gut-associated lymphoid tissue in SIV-infected long-term nonprogressing Chinese rhesus macaques on antiretroviral therapy (VIR1P.1130)
Authors: Ling Binhua , Perez Stefanie , Johnson Ann-Marie , Doyle-Meyers lara 
Published: January 2023

Abstract
HIV infected long-term nonprogressors (LTNPs) and elite controllers (ECs) maintain enduring control of HIV infection without antiretroviral therapy. However, persistent tissue reservoirs and chronic inflammation still exist. We previously found that 1/3 of SIV-infected Chinese rhesus macaques mimics HIV-infected LTNPs/ECs. Here we studied whether therapy can further decrease tissue reservoirs, restore immune function and decrease inflammation in this model. Six LTNPs/ECs and 4 progressors were treated with PMPA and FTC daily for up to 24 weeks during chronic infection. Blood, lymph nodes and gut tissues were collected. Cell-associated viral DNA levels from purified CD4+ T cells in blood and gut lymphocytes were quantified by real-time PCR. The size of reservoirs was evaluated by quantitative coculture assays and real-time PCR. Immune cells restoration including IL-17+ subsets, proliferation and immune activation were monitored by flow cytometry. We found that plasma viral loads in all animals were suppressed and maintained to undetectable throughout ART. The levels of IL-17 expression in CD4 and CD8 T cells were not fully restored but slightly increased after ART. Immune activation significantly decreased. In conclusion, the ChRM nonhuman primate model is excellent for testing novel therapeutic interventions on TP and LTNPs/ECs for HIV eradication. Initiation of ART may be necessary for improvement of immune function for HIV/SIV infected LTNP/ECs.
Epigenetic modulation of immune response in salmonid cells infected with the infectious pancreatic necrosis virus (VIR2P.1173)
Authors: Carcamo Juan , Manriquez Rene , Vera Tamara , Avendaño-Herrera Ruben 
Published: January 2023

Abstract
The great growing of salmon farming has brought a noteworthy increase in infectious diseases, generating important economic losses in the aquaculture industry. The infectious pancreatic necrosis virus (IPNV) is an agent of high mortalities in fish farmed. The aim of this study is elucidate whether the antiviral response caused by IPNV is through epigenetic mechanisms. Studies of methylation in CpG islands of the promoters of cytokines in infected salmonids cells with IPNV and treatments with DNA methyltransferase (DNMT) inhibitors were performed to evaluate the effect on the expression of cytokines. We observed that expression of cytokines, in salmonids cells infected with IPNV was associated to the promoter methylation status. Moreover, DNA methyltransferase inhibitors were able to modulate the expression of these cytokines. Our work suggested that epigenetic mechanisms participate in the regulation of host genes expression in IPNV infection.
The intracellular pathway for MR1 presentation of vitamin B-related antigens
Authors: Villadangos Jose A 
Published: January 2023

Abstract
Compounds related to Vitamin B metabolism (“VitB Ags”) produced by pathogens were recently discovered as a novel family of Ags that are presented by the MHC-I like molecule, MR1, to Mucosal-Associated Invariant T (MAIT) cells. In stark contrast with the mechanisms involved in presentation pathways for peptide and lipid Ags by MHC and CD1 molecules, respectively, the MR1 presentation pathway for VitB Ags remains largely uncharacterized.
We show that MR1 does not constitutively present self-ligands in the steady-state, but accumulates in a ligand-receptive conformation within the endoplasmic reticulum (ER). Exogenous VitB Ags reach the ER, where they form a Schiff base with a lysine residue in the MR1 Ag-binding cleft. Formation of this covalent bond serves as a “molecular switch” that allows complete folding and egress of MR1-VitB Ag complexes out of the ER. The MR1-Ag complexes follow the secretory pathway, whereupon their half-life on the plasma membrane is independent of the affinity of the bound ligand. They undergo endocytosis and although some MR1 molecules acquire new ligands during passage through endosomes and recycle back to the surface, most are degraded intracellularly. Presentation of VitB Ags on the plasma membrane of MR1 antigen presenting cells thus decreases rapidly after the cells are no longer exposed to the ligand.
In summary, the MR1 Ag presentation pathway possesses two main features that set it apart from the MHC and CD1 presentation pathways: (i) it presents exogenous VitB Ags but binding of these antigens to MR1 occurs within the ER rather than in the endocytic route; (ii) It is characterized by a rapid “off-on-off” mechanism strictly dependent on Ag availability.
An animal component-free, serum-free culture method for generation of human dendritic cells
Authors: Tabatabaei-Zavareh Nooshin , Le Fevre Timothy A. , Wognum Albertus W. , Szilvassy Stephen J. , Thomas Terry E. , Eaves Allen C. 
Published: January 2023

Abstract
Dendritic cells (DCs) are central regulators of adaptive immune responses that potentially have major applications in the immunotherapy of cancer and autoimmune disorders. DCs are rare in peripheral blood (PB) and are therefore often generated in vitro from PB monocytes. We developed an animal component-free (ACF) and serum-free medium, ImmunoCult-ACF DC, that supports the generation of DCs from monocytes in culture. CD14+ monocytes were isolated using EasySep immunomagnetic separation and cultured for 5 days in ImmunoCult-ACF DC medium and cytokines (GM-CSF and IL-4) to promote their differentiation into CD14−CD83− immature DCs. The immature DCs were then stimulated for 2 days with the ImmunoCult-DC Maturation Supplement, a combination of cytokines and pro-inflammatory mediators, to promote their maturation to CD14− CD83+ DCs (93 ± 5% CD83+, n=23). The yield of mature DCs was 42 ± 23% (n=23), similar to the yield in a control serum-free medium (49 ± 24%, n=16). Mature DCs produced high levels of IL-12, on average 371 pg/mL (range: 27–1756, n=9 in cultures initiated with 106 monocytes). Mature DCs loaded with CMV, EBV and Flu virus peptides efficiently stimulated the proliferation of autologous CD8+ T cells in 7 day co-cultures. An 18-fold increase in T cell numbers (range: 5–31, n=4) was observed when compared to control culture conditions containing only T cells without mature DCs. In conclusion, functional DCs can be efficiently generated by differentiation of monocytes in a completely animal (including human) component-free and serum-free medium. This medium and culture method will enable further research into the development and application of DCs for cellular therapy.