bluuebunny/crossref_metadata_2025_split huggingface dataset:
Paradoxical requirement for T cell expressed MyD88 for long term allograft survival (73.2)
Authors: Borges Christopher , Kim Beom , Turka Laurence 
Published: January 2023

Abstract
The TLR-MyD88 signaling pathway enables the innate immune system to sense inflammation and promote adaptive immune responses. Previously, we have shown that T cell intrinsic MyD88 signaling promotes T cell survival and is required for optimal responses to pathogens such as T. gondii and LCMV. Here, we utilized MyD88flox/flox x CD4-Cre (MyD88ΔT) mice to test how T cell expressed MyD88 affected the alloimmune response. MyD88ΔT mice (B6 background) rejected bm12 allogeneic skin with the same kinetics as C57BL/6 wild type mice, but, were resistant to the induction of long-term graft survival with αCD154, rapamycin, CTLA4Ig and donor splenocytes. Furthermore, in the bm12→B6 cardiac allograft model, where wild-type recipients spontaneously accept their grafts in a Treg dependent manner, we found that MyD88ΔT recipients acutely rejected their transplants (MST - ~30d). Consistent with this, although MyD88ΔT mice had normal numbers of Foxp3+ cells in lymphoid organs, infusion of wild-type Tregs into MyD88ΔT mice prior to heart transplantation reconstituted long-term graft survival, while depletion of CD25+ cells in MyD88ΔT recipients enabled long-term graft survival. Our data show that MyD88ΔT mice can mount an effective response against alloimmune antigen despite having abnormal responses to infection. Intriguingly, MyD88ΔT mice appear to have a defective regulatory compartment, suggesting that MyD88 signaling may be required for Treg function and/or stability.
AGO-CLIP-Chips reveal a distinct miR-mRNA interaction maps in alloantigen activated T cells (73.3)
Authors: Sun Yaping , Toubai Tomomi , Nieves Evelyn , Tawara Isao , Reddy Pavan 
Published: January 2023

Abstract
Following allo BMT, donor T cells that respond to allo-antigens cause GVHD and those that respond to non-alloantigens are critical for reconstitution, the molecular landscape and whether they are distinct is unknown. miRs regulate gene expression, but target prediction is a challenge. AGO is the central component in AGO-miR-mRNA complex. CLIP followed by microarray allows to look into the miRs’ direct target mRNAs. 45 miRs that differentially enriched in T cells, activated either by Allo-antigen or CD3/CD28 were divided into 4 groups and only 19 miRs were enriched in allo-T cells when compared to Ab-T cells. Six of the 19 were selected in further analysis. The enrichments of transcripts for mRNAs were screened with Affy. microarray. After CLIP, 1426 transcripts were detected in Allo-T cells and 1514 transcripts were in Ab-T cells. Amongst these, 200 transcripts were differentially enriched in allo-T cells and 288 in Ab-T cells. We predicted the miR targets by multi-algorithms based on CLIP-chip results and hypothesized that reduced miR enrichments should be companied with reduced mRNA transcript enrichments. Cyb5r3, LPP, Wapal, Synji1, Med17 and Fchsd2 were targets of miR-142-3p, -669D,-142-5p and -16. These miRs and above targets were validated with pool transcripts, PCR, WB and in vivo following BMT. We demonstrated for the first time, the distinct miR-mRNA interaction map based on CLIP-Chip and identified the specific targets in allo-activated T cells.
The role of NKT cells in immune evasion of liver metastases arising from intraocular tumors (74.12)
Authors: Sadegh Leila , Niederkorn Jerry , Chen Peter 
Published: January 2023

Abstract
Uveal melanoma is the most common intraocular tumor in adults within the United States. Half of the patients develop liver metastases, which is almost universally fatal. We have previously demonstrated that liver natural killer (NK) cell-antitumor immunity was suppressed in mice bearing ocular tumors, and natural killer T (NKT) cells were responsible, in part, for liver NK cell suppression. This study examines the role NKT cells in promoting liver metastases arising from intraocular tumors. We showed that when wild type and NKT-deficient C57BL/6 mice were injected with B16LS9 melanoma cells, NKT-deficient mice developed less liver metastasis than wild type mice. The cytotoxicity of liver NK cells was also assessed. Results indicated that NK cells from NKT-deficient mice were more cytotoxic compared to NK cells from wild type mice. However, in-vitro assays suggested that NKT cells were unable to directly suppress NK cell-mediated cytotoxicity. To investigate the potential role of a third-party cell, myeloid derived suppressor cells (MDSCs) were depleted by anti-GR1 antibody. Surprisingly, tumor bearing MDSC-depleted mice developed more liver metastases than isotype-treated mice. Our results imply that liver NKT cells suppress NK cell cytotoxicity through a GR1+ third-party cell population other than MDSCs. We are currently investigating whether liver NKT cells impart their immunosuppressive function through GR1+ neutrophils.
Treatment of pancreatic cancer with bifunctional siRNA silencing TGF-b and activating RIG-I (74.13)
Authors: Düwell Peter , Ellermeier Jonathan , Wei Jiwu , Hoves Sabine , Endres Stefan , Schnurr Max 
Published: January 2023

Abstract
A hallmark of pancreatic cancer is deregulated transforming growth factor-b (TGF-b) signaling which promotes tumor growth and entertains a potent immunosuppressive network correlating with poor prognosis. To brake immune suppression, we designed siRNA molecules silencing TGF-b1 and introduced a 5’ppp-modification (ppp-TGF-b) to additionally activate the cytosolic helicase retinoic acid-inducible gene I (RIG-I). RIG-I recognizes ppp-RNA motives in viral RNA and triggers type-I IFN production. We found that human pancreatic cancer cells express functional RIG-I. Treatment with ppp-RNA resulted in IRF-3 phosphorylation, type-I IFN and CXCL10 secretion, and tumor cell apoptosis. Treatment of mice with syngeneic orthotopic pancreatic tumors with ppp-TGF-b (i.v.) resulted in reduced tumor-associated TGF-b levels, systemic immune activation and high IFN levels in serum and tumor. Furthermore, ppp-TGF-b induced caspase-9-mediated tumor cell apoptosis in vivo and significantly prolonged survival of tumor-bearing mice. The development of bifunctional ppp-siRNAs that combine TGF-b silencing and RIG-I activation in one molecule represents an innovative strategy for the treatment of pancreatic carcinoma.
A small molecule inhibitor of the TGF β type I Receptor suppresses UVB-Induced mouse Skin Carcinogenesis (74.3)
Authors: Ravindran Anand , Mohammed Javed , Gunderson Andrew , Glick Adam 
Published: January 2023

Abstract
Ultraviolet radiation is a key environmental mutagen and chronic exposure to UVB is the leading cause of Skin Cancer. Transforming Growth Factor (TGF-β) represents an important immunoregulatory cytokine in the skin microenvironment with context dependent role in modulating tumor formation and progression. The immune system plays a critical role in containing the toxic damage caused by UVB; TGF-β has been known to play a key role in the activation and survival of immune cells. However, the specific role of TGF-β signaling in UVB induced skin cancers is not clear. To study this interplay between UVB, TGF-β and the immune system, we performed a UVB carcinogenesis study in the presence or absence of SB431542, an inhibitor of TGF-β1 type I receptor. We observed a significant decrease in the number of papillomas with TGF-β1 pathway inhibition and a concomitant decrease in the tumor infiltration and activation status (IFNγ secretion) of CD4 and CD8 lymphocytes. In order to understand the mechanism of suppression of T cell response by SB431542, we analyzed antigen presentation by dermal dendritic cells and langerhans cells. Preliminary data suggests that inhibition of TGF-β1 pathway suppresses the migration of skin DC subsets to the lymph nodes in response to UV, in turn suppressing the T lymphocyte response. In summary, the TGF-β1 pathway is important for the activation of the inflammatory response to UVB irradiation of the skin, which maybe mediated through Dendritic cells.
Adjuvant-carrying targeted Synthetic Vaccine Particles (tSVP™) augment the immune response to encapsulated antigen and exhibit strong local immune activation without inducing systemic cytokine release (75.3)
Authors: Ilyinskii Petr , Roy Chris , O’Neil Conlin , Browning Erica , Pittet Lynnelle , Altreuter David , Kishimoto Kei 
Published: January 2023

Abstract
Augmentation of immunogenicity can be achieved by particulate delivery of an antigen and also by its co-administration with an adjuvant. However, many adjuvants initiate strong systemic inflammatory reactions resulting in safety concerns. Here we show that co-delivery of an antigen encapsulated into synthetic polymer nanoparticles with TLR7/8 or TLR9 agonists results in a strong elevation of immune responses which does not involve systemic production of inflammatory cytokines. In contrast, antigen admixed with free TLR7/8 agonist leads to lower immunogenicity and to rapid induction of serum cytokines associated with toxicity and immune suppression (e.g., TNF-α and IL-6 levels are 50-200 times higher upon injection of free than of encapsulated TLR7/8 agonist). Conversely, local immune stimulation as seen by cellular infiltration of draining lymph nodes and by intranodal cytokine production was much more pronounced and persisted longer if particle-encapsulated TLR agonists were used. Moreover, particle encapsulation permitted the efficient utilization of immunostimulatory CpG sequences with an enzyme-labile phosphodiester backbone which are known to rapidly degrade in vivo. The strong local immune activation in lymph nodes which resulted in a marked augmentation of immunogenicity was achieved using a modular self-assembling polymer nanoparticle platform and was equally efficient whether antigen and adjuvant were encapsulated in a single particle or in two separate particles.
A humanized mouse model for generation of tumor antigen specific T cells for preclinical research and anticancer therapy (75.4)
Authors: Hu Zheng , Wargo Jennifer , Yang Yong-Guang 
Published: January 2023

Abstract
Adoptive transfer of tumor-specific TCR-engineered T cells is a promising cancer therapy, but mispairing of endogenous TCRαβ chains with introduced TCR subunits remains a major limiting factor. T cells with mispaired TCRαβ chains, not only lose anti-tumor activity, but also convey potential risk of graft-vs.-host manifestations. In this study, we attempted to generate human T cells expressing only the engineered, tumor-specific TCR in humanized mice, which were made by transplantation of NSG mice with HLA-A2+ fetal human thymic tissue (under kidney capsule) and CD34+ fetal liver cells (i.v.) that were lentivirally transduced with HLA-A*0201-restricted Mart-1-specific TCR gene. MART-1:26-35(27L)/HLA-A*0201 tetramer+CD8 T cells became detectable in blood by 6 wks and reached to more than 70% by 14 wks. Following immunization with Mart-1 peptides, over 60% tetramer+CD8 T cells converted from a naïve phenotype to CD45RA-CCR7- effector/memory phenotype and acquired the ability to produce IFN-γ, while tetramer-CD8 T cells remained a naïve phenotype and incapable of IFN-γ production. Almost all tumor-infiltrating T cells were tetramer+CD45RA-CCR7-CD8+. Tetramer+ CD8 T cells mediated efficient specific killing of HLA-A2+Mart-1+ melanoma cells, and the cytolytic activity retained after substantial in vitro expansion (up to thousands of times) for about two months. Thus, this hu-mouse model may provide an efficient means of generating human T cells with potent anti-tumor activity.
T cell responses targeting subdominant epitopes of Mycobacterium tuberculosis antigen ESAT-6 resist acquisition of bacteria-driven functionality and enhance protection in vivo. (75.8)
Authors: Woodworth Joshua , Aagaard Claus , Agger Else Marie , Andersen Peter 
Published: January 2023

Abstract
Immune-mediated pathology drives M.tuberculosis (Mtb) disease and transmission. Hyperconservation of dominant T cell epitopes in Mtb’s genome suggests that the T cell response to infection is actually evolutionarily beneficial to Mtb. Vaccine-induced CD4 T cells recognizing novel subdominant epitopes of ESAT-6 that are not targeted during natural infection can improve protective. We investigate differential characteristics of dominant vs subdominant T cells in protective immunity to Mtb in vivo. Methods. CB6F1 Mice were vaccinated with either rESAT-6 or a truncated ESAT-6, which lacks the dominant epitope and induces subdom T cell responses. Before and after Mtb infection, epitope-specific T cell responses were evaluated by proliferation, cytokine secretion, flow cytometric assays. Results. Pre-infection, subdom CD4 T cells had enhanced proliferation, but delayed cytokine kinetics. Post-infection, vaccine-induced T cells had a markedly different cytokine profile relative to infection-driven T cells, including memory-like polyfunctionality and IL-17 production. However, over time, a larger proportion of dominant T cells developed an infection-driven cytokine and KLRG1/PD-1 profile. Conclusion. Subdom epitope CD4 T cell have enhanced maintenance of vaccination-induced cytokine profile following infection in vivo, associated with their ability to enhance protection, and therefore may be uniquely able to resist bacterially-driven modulation and immune-mediated disease.
Bystander chronic infection negatively impacts the development of CD8 T cell memory (76.6)
Authors: Stelekati Erietta , Shin Haina , Doering Travis , Dolfi Douglas , Ziegler Carly , Beiting Daniel , Liboon Jennifer , Wolski David , Katsikis Peter , Shen Hao , Roos David , Haining W. , Lauer Georg , Wherry E. 
Published: January 2023

Abstract
Accumulating epidemiological evidence suggests that chronic infections compromise immunity against antigenically unrelated infections, but the underlying mechanisms are unclear. We investigated whether antigenically unrelated “bystander” chronic infections impacted the development of memory CD8 T cells, the hallmarks of protective immunity against intracellular pathogens. We demonstrate that chronic bystander infection and inflammation substantially impair memory CD8 T cell responses in several mouse models with similar changes in non-human primates and in chronically HCV -infected humans. Type I IFN -induced molecular pathways were specifically dysregulated in memory CD8 T cells in inflammatory environments and induction of type I IFN by chronic poly(I:C) administration similarly impaired memory CD8 T cell development and function. Chronic inflammation increased the expression of the proapoptotic protein Bim in bystander CD8 T cells, while inhibiting their IL15-induced rescue from apoptosis ex vivo. Two transcriptional regulators of T cell development, Blimp-1 and T-bet, integrated the effects of inflammatory mediators in impairing optimal memory CD8 T cell development. Thus, exposure to chronic bystander infections deregulates the normal effector to memory CD8 T cell transition. These results have direct relevance concerning current therapeutic approaches and vaccination strategies for patients with persisting infections or chronic inflammatory conditions.
Evaluation of immune response in dorsal root ganglion of mice infected with Herpes Simplex Virus type 1 (HSV-1) (76.8)
Authors: Silva Jaqueline , Talbot Jhimmy , Lopes Alexandre , França Rafael , Fonseca Benedito , Cunha Thiago , Cunha Fernando 
Published: January 2023

Abstract
Herpes Zoster (HZ) is a disease caused by reactivation of latent herpesvirus Varicella Zoster in the sensory ganglion, characterized by dermal rash and severe pain. A model of mice infected with HSV-1 on the skin of the hind paw has been used to study the pathophysiology of HZ, since they develop HZ-like skin lesions and pain-related responses. There are no data available about the immune response in dorsal root ganglion (DRG) of these mice. Thus, the aim of this study was to evaluate cells and inflammatory mediators present in DRGs and its relationship with hypernociception during HSV-1 cutaneous infection. Mice developed hypernociception from day 3 to 7 post inoculation in the ipsilateral (Ips) paws, but not in the contralateral (Cl) paws. A higher viral load, measured by qPCR, was detected in DRGs L3, L4 and L5 of infected mice, when compared to control mice or naïve mice. By flow citometry analysis, we observed an inflammatory infiltrate composed by CD4+, CD8+, CD11b and Gr1+ cells in DRGs L3, L4 and L5, but not in spinal cord, that correlated with virus presence previously found. A higher expression of COX-2, IFN-γ, GFAP and IL-22 was detected in the same DRGs of Ips paws from infected mice, when compared to the same ganglion of Cl paws or ganglion from naïve mice. Our results show the presence of an inflammatory infiltrate in DRGs of infected mice and the expression of inflammatory mediators which might contribute for the development of hypernociception.
A potential role for HLA-DM in linking the antigen uptake and antigen presentation pathways in B cells. (P5007)
Authors: Macmillan Henriette , Strohman Michael , Ayyangar Sashi , Mellins Elizabeth 
Published: January 2023

Abstract
Antigen presenting cells (APC) are key regulators of immunity. They are involved in stimulating naïve and effector cells and are critical for orchestrating protective responses to infectious agents as well as aberrant responses to self-antigens. Among APC, B cells are uniquely capable of presenting small amounts of antigen, which they capture and take up through surface immunoglobulin (Ig). The uptake of antigen by B cells is well studied, and so is the loading of peptides onto MHC II, but how these two pathways intersect is less well elucidated. We propose that HLA-DM is a key factor in linking these pathways by interacting with Ig. Here we show that HLA-DM and Ig can be co-precipitated from B cell lines. We also utilized proximity ligation assays and confocal microscopy to show a close interaction between HLA-DM and Ig in fixed B cell lines. In addition, we show by western blot and FACS staining that mutant cell lines lacking HLA-DM have lower levels of Ig than their parent, DM-expressing cell lines. Our data suggest that HLA-DM is involved in linking the antigen uptake and antigen presentation pathways by interacting not only with MHC II but also with Ig.
Evolution of HLA class II through diversification in protein stability levels (P5009)
Authors: Miyadera Hiroko , Ohashi Jun , Tokunaga Katsushi 
Published: January 2023

Abstract
Allelic diversity in human leukocyte antigens (HLA) have been explained by balancing selection acting on polymorphic residues in the peptide binding groove of HLA that diversify binding spectrum for pathogenic epitopes. Here we show that HLA class II (HLA-DQ) allele products are extremely diverse in protein stability levels. We have profiled the relative stability of DQ proteins by a cell-based assay that measures cell surface MHC protein density (surface density index; SDI). The SDI varies over 100-fold among DQ allele products, indicating large stability differences. Through mutagenesis, we identified polymorphic residues that regulate the intrinsic stability of DQ protein, which includes variations on the exterior of the peptide-binding groove that mediate interdomain hydrogen bonds. One of the major stability regulator in DQA1 achieves high ratio of synonymous to non-sysnonymous substitutions per site (ds/dn), suggesting that variations at this site have been maintained through balancing selection. DQ genes of non-human primates and mammals also maintain these variatns. These data suggest that HLA and MHC have been evolving through diversifications in protein stability levels. Our study provides new functional insights into the mechanism of HLA evolution.
The development of thymic B cells and their role in T cell negative selection (P5039)
Authors: Perera Jason , Meng Liping , Huang Haochu 
Published: January 2023

Abstract
T cell negative selection is dependent on the presentation of self antigens by MHC expressing cells in the thymic medulla. In addition to dendritic cells and medullary thymic epithelial cells, thymic B cells also reside in the medulla and express high levels of MHC class II. The origin of these cells is unclear, with both intrathymic development and recirculation of mature B cells being reported. Using parabiosis studies and analysis of Rag-2-GFP BAC transgenic mice, we found that recirculation contributes minimally while development from thymic progenitors is the predominant pathway that maintains this population. Given their phenotype and high capacity to present cognate antigens, we hypothesized that thymic B cells play a role in T cell negative selection. Using the KRN TCR transgenic that recognizes the self antigen GPI, we tested how negative selection was affected when we altered B cell antigen presentation. When the KRN TCR was crossed to a GPI-specific BCR knockin that increased GPI presentation on B cells, negative selection of the KRN TCR was enhanced. When we eliminated thymic B cells by crossing the KRN TCR onto a μMT-/- background, negative selection was reduced, suggesting that the endogenous B cell repertoire contributes to negative selection of this physiologically relevant antigen. Given the high frequency of autoreactivity in immature B cells, we argue that B cell tolerance and T cell tolerance could be efficiently coupled in T cell negative selection.
Type I interferon induced by lymphotoxin-beta receptor signaling on dendritic cell is crucial for CD8 T cell infiltration into effector site by modulating the expression of tissue specific adhesion molecule VLA4 (P5045)
Authors: Ng Dennis , Ward Lesley , Rahbar Ramtin , Cummings Derek , Mossman Karen , Ohashi Pamela , Gommerman Jennifer 
Published: January 2023

Abstract
In non-infectious settings with minimal inflammatory stimulus, CD4 T cell help is needed for dendritic cells (DC) to cross-prime antigen in order to elicit a CD8 T cell response. Activated CD4 T cells express CD40-ligand (CD40L) and lymphotoxin-α1β2 (LTαβ), which interacts with their respective TNF receptors, CD40 and lymphotoxin-β receptor (LTβR) on DC, thereby significantly increases the DC immunogenic potential. Our early work showed that LTβR signaling induces Type I IFN expression in DC which facilitates CD8 T cell expansion against soluble protein antigen. In this study, we identified that LTβR signals through TNF receptor-associated factor (TRAF)-3 for interferon regulatory factor (IRF)-3 phosphorylation and Type I IFN production. Furthermore, using an inducible diabetes model through the transfer of activated DC, we found that LTβR signaling on DC is absolutely required for the proper priming of CD8 T cells and diabetes induction. We further showed that LTβR-induced Type I IFN affect the expression of the adhesion molecule VLA-4 on antigen specific CD8 T cells and it affects their ability to infiltrate into the pancreas. LTβR deficient DC fail to induce diabetes, and the provision of exogenous IFN-α was sufficient to rescue the diabetes status. Together, these results describe a novel role for LTβR in the induction of Type I IFN by DC, and demonstrate its relevance in an autoimmune setting.