bluuebunny/crossref_metadata_2025_split huggingface dataset:
T lineage precursors from diabetes-prone NOD mice exhibit defective alpha-beta and enhanced gamma-delta T cell development (99.20)
Authors: Yui Mary A. , Rothenberg Ellen V. , Feng Ni 
Published: January 2023

Abstract
Because defects in various T lineages have been suggested to contribute to autoimmune diabetes in NOD mice, we sought to determine if early T cell precursors from NOD mice exhibit developmental abnormalities, which might affect later T cell lineage choices and responses. We previously reported that early T cells from NOD.Rag-/- mice undergo a spontaneous breakthrough at the first TCR-dependent checkpoint, a trait that appears to map near to two diabetes susceptibility genetic regions. We have also found that purified early T cell subsets from wild-type NOD mice undergoing differentiation in vitro exhibit profound defects in the generation and maintenance of DP populations, while gamma-delta T cell development is enhanced. NOD thymocytes also exhibit defects in development to the DP stage in vivo. These results show that NOD T cells have a lineage-specific abnormality at the first TCR-dependent checkpoint, which may select for DP cells with skewed signaling and/or survival characteristics, potentially altering positive and negative selection thresholds, T lineage choices, peripheral responses, and autoimmunity. (Supported by Juvenile Diabetes Foundation International and NIH R01AI064590 (to MAY).)
Identification of serum proteins that inhibit lupus immune complex stimulation of plasmacytoid dendritic cells (99.34)
Authors: Santer Deanna , Elkon Keith B 
Published: January 2023

Abstract
Regulation of IFN-α produced by plasmacytoid dendritic cells (pDC) is critically important in Systemic Lupus Erythematosus (SLE) as patients have an 'IFN-signature' which correlates with disease severity. We observed that, normalized for IgG, SLE patient cerebrospinal fluid (CSF) induced 800-fold more IFN-α by pDCs compared to paired serum due to potent inhibitory factors in serum.
Depletion of IgG from normal serum and addition of purified IgG to SLE immune complex (IC) stimulation assays revealed that normal IgG was one inhibitor in serum. Although the inhibitory capacity of IVIG has recently been attributed to a small subfraction of sialylated IgG in mouse models, sialylation of IgG did not significantly affect IVIG inhibition of IC stimulation of IFN-α. This result indicates either species differences or differences in pDC inflammatory pathways.
Deficiencies of early complement components predispose to SLE. Heat inactivation of normal serum and utilization of sera selectively deficient in early complement components revealed that a second serum inhibitor of IC mediated IFN-α stimulation was complement. Suppression of IFN-α produced by pDC was restored by adding back the missing complement component.
In summary, we have identified two serum factors that potently attenuate IFN-α induced by SLE ICs. Modulation of these components in vivo could be used therapeutically.
Role of IFN-γ in passive experimental autoimmune myasthenia gravis (99.4)
Authors: Brown Paul M , Wall Katherine A 
Published: January 2023

Abstract
In myasthenia gravis, anti-acetylcholine receptor (AChR) antibody is thought to cause damage through the activation of complement, via the classical complement pathway, in addition to causing internalization of AChRs. Previous research has shown that interleukin 12 (IL-12), the major inducer of IFN-γ production in the immune system, enhances clinical experimental myasthenia gravis (EAMG) in C57BL/6 (B6) mice. We performed passive transfer experiments with mAb399, a mouse anti-AChR monoclonal antibody recognizing the immunodominant mouse AChR epitope, using both B6 and IFN-γ-/- mice. The role of complement in disease induction in these mice was examined using fluorescent microscopy. When pre-treated with IL-12, B6 and IFN-γ-/- mice had similar amounts of antibody and complement bound at the neuromuscular junction, although IFN-γ-/- mice were resistant to EAMG development. This suggests that IL-12, through IFN-γ, may increase susceptibility to disease through mechanisms downstream of antibody and complement binding. (This work was supported by NIH AI 43061 and the OBOR Interdisciplinary Research Initiation Award)
Anti-apoptotic Genes are Upregulated in Tolerized CD8+ Regulatory T Cells Isolated from SLE-Prone Mice (99.41)
Authors: Skaggs Brian J , Ebling Fanny M , Singh Ram P , LaCava Antonio , Hahn Bevra H 
Published: January 2023

Abstract
Purpose: We studied the role of two different regulatory T cells (CD4+CD25+Foxp3+ Treg and TGFβ/IL10-secreting CD8+ Ts) in apoptosis pathways using a mouse model of systemic lupus erythematosus (SLE).
Methods: Ten-week old female NZB/NZW F1 mice were tolerized with a synthetic peptide based on anti-dsDNA VH sequences (pCons) that delays SLE symptoms or isotonic saline and killed one week later (n=6/group). After Treg and Ts isolation from spleens, gene transcript levels from three different pathways - apoptosis, T cell tolerance, and TGFβ - were examined by real-time PCR-based gene arrays (SA Biosciences). These platforms contain primers for 84 pathway-specific genes.
Results: Differences in Treg mRNA between the two groups were not apparent. In Ts, however, Bcl2, survivin, COX-2, Pak7, and IL-10 transcripts were significantly elevated more than two-fold in the pCons group. The proapoptotic gene Apaf1 was also significantly downregulated, implicating inhibition of specific caspases. Western blot confirmed altered protein regulation of these genes. Bcl-2, survivin and COX-2 are direct targets of the antiapoptotic transcription factor NF-κB, and Apaf-driven signaling pathways are involved in NF-κB regulation.
Conclusions: Results from these experiments provide additional insights into Ts apoptosis in SLE and could lead to novel therapeutic options designed to alter Ts biology.
IL-12/STAT4 SIGNALS ARE CRITICAL IN AUTOIMMUNE RESPONSE (99.44)
Authors: Yang Yu , Xu Jiangnan , Ochando Jordi C , Bromberg Jonathan S , Ding Yaozhong 
Published: January 2023

Abstract
Mice deficient in Th1 transcription factors T-bet or Stat4, are severely impaired in their ability to produce IFNγ and Th1 cells, and are resistant to the development of autoimmune diseases. Here, we introduced Stat6 deficiency into T-bet deficient mice to limit interference from elevated levels of IL-4/Stat6/GATA-3 Th2 polarizing signals, and to examine roles of T-bet and IL-12 in Th1 differentiation and colitis development. We found that eliminating IL-4/Stat6/GATA3 Th2 signals restored IL-12Rβ2 expression in T-bet deficient cells, and enabled T-bet deficient CD4 T cells to regain the ability to respond to IL-12 for IFNγ induction. Whereas T-bet deficiency abolished colitis development, transfer of Stat6 and T-bet double deficient CD4+CD25-CD45RBhigh T cells leaded to weight loss and colitis. Our data indicated that T-bet is not absolute for Th1 development and colitis induction, and demonstrated the critical role of IL-12/Stat4 in IFNγ production, Th1 development, and autoimmune disease development.
A self-peptide with large anchor residues binds IAd and induces Th2-like autoimmune gastritis (99.45)
Authors: Revilleza Maria Jamela Roxas , Levin Ditza , Mage Michael G , Teyton Luc , Robinson Howard , Shevach Ethan M , Natarajan Kannan 
Published: January 2023

Abstract
A mouse model of autoimmune gastritis with Th2-like phenotype in which BALB/c mice expressing a transgenic αβ TCR spontaneously develop the disease was developed in our laboratory. The TCR recognizes a 12-mer peptide from the alpha subunit of gastric parietal cell H/K ATPase presented in the context of IAd. The disease is characterized by slow and incomplete penetrance, anti-gastric mucosal cell antibodies, inflammatory eosinophilic infiltrates, parietal cell destruction and elevated Th2 cytokines. To investigate the contribution of MHC/peptide interactions to the initiation and maintenance of AIG, we generated a soluble recombinant version of the IAd/H/K ATPase889-900 complex for biophysical and crystallographic analyses. The 2.5 Å X-ray structure of the complex reveals rare features not seen in other IAd/peptide complexes: cysteine in P1, an imino acid in P6, and a large acidic residue in P9. This first structure of IAd in complex with an autoimmunogenic peptide reveals a previously unrecognized peptide binding motif for IAd with large anchor residues and with GLU in P9 encapsulated by a web of polar contacts that may contribute to stabilization of the complex and to maintenance of antigen presentation in disease.
This research was supported by the Intramural Research Program of the NIH, NIAID.
IL-15 prolongs CD154 expression via STAT5 engagement of the proximal CD154 promoter (99.48)
Authors: Cron Randy Q , Genin Anna , Orgun Nural N 
Published: January 2023

Abstract
CD154 expression is tightly regulated but increased expression on CD4 T cells in mouse models and humans with lupus contributes to disease. Since IL-15 is increased in lupus serum, we explored an IL-15 contribution to prolonged CD154 expression. Flow cytometry reveals increased CD154 levels on primary CD4 T cells following IL-15 plus PHA stimulation at later time points (48 hrs). Since IL-15 signals via STAT5 we explored the hCD154 promoter for possible STAT5 binding sequences (TTCNNNGAA). Gel shift assays with nuclear extracts from IL-15-activated primary human CD4 T cells reveal a proximal site (-65 bp) binds STAT5. Binding of STAT5 to the proximal CD154 promoter was confirmed in vivo by chromatin immunoprecipitation. Functionally, over-expression of wild-type STAT5 in primary CD4 T cells increases CD154 transcriptional activity in a dose-dependent fashion following T cell activation. Mutation of the STAT5 binding site eliminates this effect. Moreover, over-expression of dominant-negative STAT5 inhibits CD154 transcription. Similarly, STAT5 siRNA inhibits CD154 protein expression at late time points (48 hrs) post-T cell activation. Interestingly, STAT5 remains phosphorylated at late time points post-activation when IL-15R[alpha] expression is increased. The fact STAT5 binds the CD154 promoter in response to IL-15 provides novel approaches to CD154 inhibition via anti-IL-15 antibody, or by JAK3 inhibitors.
The role of Drak2 in the generation and function of regulatory T cells (99.54)
Authors: Hernandez Jeniffer B. , Walsh Craig M. 
Published: January 2023

Abstract
Autoimmune disease occurs via the escape of autoreactive T cells from central or peripheral tolerance mechanisms. T cells lacking the serine/threonine kinase Drak2 have a diminished activation threshold, suggesting that Drak2 serves as a quiescence factor to maintain tolerance to weak self-antigens. Drak2-/- mice are resistant to organ-specific autoimmune diseases such as EAE and IDDM. We have observed enhanced apoptosis in effector T cells derived from Drak2-/- mice, suggesting that Drak2 serves as a survival factor in effector T cells. Given the ability of Treg to prevent autoimmunity, we have investigated the potential that Drak2 may contribute to the generation or function of Treg. We have observed a significant increase in the ratio of Treg relative to conventional T cells (Tconv) in Drak2-/- mice. The increased Treg observed may be a consequence of enhanced differentiation of Drak2-/- Tconv toward adaptive Treg. Indeed, culture of naïve, Drak2-/- Tconv with plate-bound anti-CD3 alone resulted in the induction of a significant population of Treg. We hypothesize that the autoimmune resistance observed in Drak2-/- mice is due to the increased proportion of Treg and that DRAK2 may modulate regulatory T cell function. These results highlight the potential for inhibiting autoimmunity without affecting anti-pathogen responsiveness via DRAK2 blockade. This work was supported by NIH grant R01AI063419.
Immunosuppressive Ovarian Cancer-Infiltrating Dendritic Cells can be transformed into Immunostimulatory Cells through In situ CD40 and Toll-like Receptor 3 Stimulation (100.32)
Authors: Scarlett Uciane , Cubillos-Ruiz Juan , Nesbeth Yolanda , Martinez Diana , Fields Jennifer , Gewirtz Andrew , Ahonen Cory , Conejo-Garcia Jose 
Published: January 2023

Abstract
The individualized targeting of tumor-induced immunosuppression may contribute to the advancement of therapy against lethal epithelial tumors. We find that in a newly developed transgenic model of ovarian cancer, CD11c+MHCII+ dendritic cells are the most abundant leukocyte subset at tumor sites from early tumorigenesis. We also demonstrate (using a transplantable tumor model) that in the ovarian carcinoma microenvironment, these cells spontaneously engulf tumor materials and instead of promoting anti-tumor immunity, suppress T cell function. In situ co-stimulation of CD40 and Toll-like receptor (TLR) 3 on tumor-infiltrating dendritic cells reduced their L-arginase activity as well as enhanced their production of pro-inflammatory cytokines, augmented their capacity to process antigens, and up-regulated costimulatory molecules in vivo in mice and in vitro in human dissociated tumors. Correspondingly combined CD40/TLR agonists boosted measurable T-cell-mediated antitumor immunity and induced the rejection of otherwise lethal ovarian carcinomas. These results underscore the potential of transforming tumor-infiltrating dendritic cells from an immunosuppressive to an immunostimulatory cell type. Lastly, combined administration of synergistic CD40 and TLR3 agonists could enhance their individual therapeutic effects against ovarian and other lethal epithelial cancers.
Survivin: A Potential Target of Adoptive Immunotherapy for Pediatric Sarcomas (101.19)
Authors: Cui Yongzhi , Garber Haven , Zhang Hua , Mackall Crystal 
Published: January 2023

Abstract
Cell based immunity is driven by CD8+ cytotoxic T cells bearing TCR that recognize specific tumor-associated peptides bound to class I MHC molecules. Survivin, an inhibitor of apoptosis protein (IAP), is a tumor-associated antigen that is widely expressed in nearly all human cancer cells and undetectable in most normal tissues. Although there is evidence for cytotoxic T cell responses against survivin in patients, tolerance to self antigens can be a limiting factor in generating highly avid T cells capable of killing tumor cells. An alternate approach involves peptide immunization of HLA-A2 transgenic mice that express the human class I HLA-A2 molecule, which could in principle generate more highly avid TCRs to human antigens. In this study, we vaccinated A2 transgenic mice with a modified survivin epitope, Surv96M (LMLGEFLKL) and successfully generated CD8+ CTL clones that react against Survivin96-104 and a human pancreatic cancer line. The α- and β- chains for the TCR of reactive CTLs were cloned and inserted into an retrovirus vector incorporating 2A linker peptides between coding sequences of α- and β- chains of TCRs against survivin. Transduction of survivin specific TCR retrovirus constructs into human PBMCs yielded up to 70% TCR redirected lymphocytes and specific effector function as measured by IFNgamma release following co-culture with peptide-pulsed targets and one A2+ pediatric osteosarcoma line. Ongoing work is underway to increase the TCR affinity to potency.
Targeting of breast tumors by an HLA A*0201/MIF specific antibody (101.23)
Authors: Hawkins Oriana , Verma Bhavna , Neethling Francisca , Caseltine Shannon , Lightfoot Stanley , Blakey Gregory , Dooley William , Weidanz Jon , Hildebrand William 
Published: January 2023

Abstract
We previously utilized secreted HLA technology to identify a Macrophage Migration Inhibitory Factor (MIF19-27) encoded peptide as unique to the HLA-A*0201 molecules of breast cancer derived cell lines. The aims of this study were to (1) generate a mAb specific for the A*0201/MIF complex, (2) to assess A*0201/MIF expression on primary tumors, and (3) to evaluate the cytotoxicity of the antibody to breast cancer cell lines and tumor xenografts. The RL21A mAb specific for A*0201/MIF was generated by immunizing mice with peptide/MHC complexes. Matched tumor and normal cryopreserved breast tissues were HLA typed and A*0201 tissue sections were stained with RL21A. Staining of the normal and primary tumors were compared for HLA A*0201 expression and for A*0201/MIF staining. The RL21A TCRm antibody specifically stained HLA-A*0201 positive breast tumors. This confirms the presentation of the MIF on primary breast cancer tissues and validates cancer epitope discovery using secreted HLA technology and cancer cell lines. RL21A was capable of inducing potent complement mediated (CDC) and cell mediated cytolysis (ADCC) as measured by in vitro lactate dehydrogenase (LDH) release. In addition, RL21A reduced tumor burden in a prophylactic tumor model, employing an aggressive BT20-A2 xenograft. Here we demonstrate that the HLA-based discovery of cancer epitopes can lead to the generation of mAb that specifically recognize and destroy tumors via the A*0201/peptide complex.
Origin and number of viral peptides sampled by class I MHC following West Nile Virus infection (130.27)
Authors: Laughlin Amanda , McMurtrey Curtis , Bardet Wilfried , Fogle Matthew , Wahl Angela , VanGundy Rodney , Buchli Rico , Hildebrand William 
Published: January 2023

Abstract
West Nile Virus (WNV) was introduced into the United States in 1999 and it has emerged as the most common cause of arboviral neuroinvasive disease in the U.S. An estimated 1.65 million infections occurred between 1999 and 2008 and there is no specific treatment or vaccine available. WNV-infected cells can be detected and destroyed by the CD8+ cytotoxic lymphocytes via the presentation of viral peptides by major histocompatability complex class I molecules. Currently, no one knows how many WNV derived peptides decorate the MHC of infected cells, nor do we know which viral proteins MHC molecules sample. Understanding the number and origin of viral peptides available for immune recognition is a key prerequisite in the development of antiviral immunotherapeutics. Using an HLA-A and an HLA-B molecule, we previously reported that a given class I MHC molecule samples 2-6 viral peptides. Here we test this observation with additional HLA-A and HLA-B by secreting A*0101 and B*2705 from uninfected cells and then from WNV infected cells. Peptides eluted from the infected and uninfected class I molecules were compared by mass spectrometry, and peptides unique to infected cells were sequenced by tandem mass spectrometry. The resulting data demonstrate that different class I MHC molecules consistently present a like number of WNV peptides for immune recognition and that the viral peptides originate from clusters or “hot spots” within the viral polyprotein.
DIRECT ORCHESTRATION OF CD8+ T-KILLERS BY CD4+ T-HELPERS AND CD+ T-LICENSED ANTIGEN PRESENTING CELLS (130.33)
Authors: Xiang Jim 
Published: January 2023

Abstract
We previously proposed a CD4+ Th-APC concept by demonstrating that in vitro ovalbumin (OVA)-pulsed dendritic cell (DCova)-activated CD4+ T cells acquired peptide/major histocompatibility complex (pMHC) I from DCova and are capable of stimulating CD8+ cytotoxic T lymphocytes (CTLs). In this study, we developed a novel immunization protocol to “dissect apart” respective roles of DCova, CD4+ and CD8+ T cells separately in an in vivo environment with close to physiological condition. We first used anti-CD4 and anti-CD8 antibody (Ab) and deptheria toxin (DT) for in vivo depletion of CD4+ and CD8+ T cells and DCova derived from DT receptor (DTR)-CD11c transgenic mice, respectively, at different time points of the protocol. We then assessed the priming of CD8+ CTL responses in blood using FITC-CD8 and PE-Kb/OVA257-264 tetramer staining by flow cytometry. We found that (i) mice that have CD4+ T-licensed DCova but lack CD4+ T cells by anti-CD4 Ab treatment during CD8+ CTL priming, induced CTL effector/memory responses, (ii) CD4+ T cells with in vivo acquired pMHC I, but not those without pMHC I acquisition stimulated CTL responses, and (iii) APC-primed CD4+ T cells mounted more efficient CTL effector/memory responses than CD4+ T-licensed DCova. Our results thus provide a clear in vivo evidence for a direct orchestration of CD8+ T-killers by CD4+ T-helpers and CD4+ T-licensed APCs. This conceptual advance may have great impacts in re-evaluation of antitumor and autoimmune responses.
TIM-3 is a receptor for phosphatidylserine and allelic variants differentially mediate uptake of apoptotic cells (130.41)
Authors: Bu Xia , Ballesterous Angela , Chim Yee-Ling , Santiago Cesar , Lee Hyun-Hee , Umetsu Dale , Casasnovas Jose , DeKruyff Rosemarie , Freeman Gordon 
Published: January 2023

Abstract
TIM-3 is a member of the T cell/transmembrane, Ig and mucin (TIM) gene family. TIM-3 is expressed on Th1 cells and dendritic cells and generates an inhibitory signal resulting in apoptosis of Th1 cells. We found that TIM-3 is receptor for phosphatidylserine (PtdSer) exposed on apoptotic cells. A co-crystal structure showed a similar binding mode to TIM-4/PtdSer with a deep binding pocket coordinating calcium ion with PtdSer and flanked by two hydrophobic loops that can extend into a membrane. Fibroblasts transfected with BALB/c TIM-3 more effectively bound to and phagocytosed apoptotic cells than HBA TIM-3 transfected cells. Liposomes containing equal amounts of PtdSer and phosphatidylcholine reduced phagocytosis in a concentration dependent-manner. This suggests that functional differences in TIM-3 alleles may contribute to the Th1/Th2 differences between the strains. T or B cells expressing TIM-3 formed conjugates with but failed to phagocytose apoptotic cells, suggesting a role in signaling in lymphocytes without engulfment. These findings indicate that TIM-3 expressing cells can respond to apoptotic cells through TIM-3/PtdSer binding, but the consequence of TIM-3 engagement of PtdSer depends on the polymorphic variants of and type of cell expressing TIM-3. These findings establish a new paradigm for TIMs as PtdSer receptors and unify the function of the TIM gene family, which has been associated with ashma and autoimmunity and shown to modulate peripheral tolerance.
A vaccinia virus expression system to study antigen processing of multiple recombinant proteins (130.43)
Authors: Guterman Jacqueline , Wolf Benjamin , Kumagai Chiharu , Princiotta Michael 
Published: January 2023

Abstract
A major obstacle in designing effective vaccines is our limited knowledge of the mechanisms involved in eliciting a protective cell-mediated immune response. In recent years, research has focused on the development of recombinant vaccines, in which antigenic peptides derived from a specific pathogen are delivered to the cells via live vectors. For a vaccine to be effective in an out-bred population it must generate as many antigenic determinants as possible. One method that can be used to generate multiple peptide determinants is to express two or more recombinant proteins from a single live vaccine vector. To this end, we developed a recombinant vaccinia virus system that expresses two full-length influenza virus proteins; nucleoprotein (NP) and acidic polymerase (PA). In addition to the NP and PA proteins, our expression system is designed to produce yellow and red fluorescent proteins, which allow us to monitor, in a quantitative manner, recombinant protein expression both in vitro and in vivo. Using this novel expression system we have found that the route of immunization affects the immunodominance hierarchy of the host response to not only vector-derived peptides but also to recombinant peptides.