bluuebunny/crossref_metadata_2025_split huggingface dataset:
HLA-DO inhibition of HLA-DM catalytic function is regulated by acid-promoted HLA-DO inactivation (APP5P.106)
Authors: Jiang Wei , Strohman Michael , Somasundaram Sriram , Ayyangar Sashi , Wang Nan , Hou Tieying , Macmillan Henriette , Mellins Elizabeth 
Published: January 2023

Abstract
CD4+ T cells recognize MHC-II-peptides, whose generation is controlled by HLA-DM and its inhibitor, HLA-DO. Activation of DM-DO-expressing cells alters DO:DM in favor of active DM, but the molecular mechanism(s) underlying this process are unclear. DM is known to catalyze exchange of MHC-II-associated invariant chain peptides (CLIP) for antigenic peptides. As expected, We identified the positive correlation between the total CLIP level and DO:DM, and confirmed sufficient DM inhibition in high DO:DM cells. Importantly, super-resolution microscopy shows co-localization of CLIP with only the early endsomal marker but not the lysosomal marker in these cells, indicating the pH regulation of DM inhibition by DO and the presence of active DM in lysosomes. We demonstrated that acid-expose of DM-DO complexes yields active DM, and isolated free functional DM ectodomains using size exclusion chromatography. The study of pH-effects on the interaction between soluble DM and a stabilized DO equivalent (DOaP11A) indicates that the generation of active DM from DM-DO complexes is mainly due to acid-promoted DO denaturation. It is also suggested that free DM ectodomains are subjected to acid-promoted inactivation. Therefore, association by DO may regulate the endosomal pH range of DM activity while extending DM active life span at the lysosomal pH condition. Acidification of endosomes will down-regulate DO:DM via acid-promoted DO inactivation for efficient DM catalysis.
Involvement of γδ T cells and scavenger receptors in the immunopathogenesis of Pemphigus Vulgaris (BA11P.129)
Authors: Das Dayasagar , Anand Vivek , Singh Antil Parul , Khandpur Sujay , Sharma V.K , Sharma Alpana 
Published: January 2023

Abstract
Pemphigus Vulgaris (PV) is an auto-immune blistering disease mostly due to formation of auto-antibodies against desmoglein3 (Dsg3) and aberrant T cell function. γδ T cells play significant role in the immune surveillance at the epithelial surface and modulate other immune cells. Scavenger receptors (CD36 and CD163) are Pattern recognizing receptor (PRR) molecules and key players in several inflammatory diseases. γδ T cells and its signature molecular markers has found to be involved in several autoimmune diseases. However the role of γδ T cells and associated Scavenger receptor molecules are not characterized in the Immunopathogenesis of PV. In our study we observed significantly higher frequency of γδ T cells (6.7% vs. 3.8%) and IL17 producing γδ T cells in circulation of PV patients (n=25) vs. controls (n=15) respectively along with Th1 polarization (p&lt;0.010) suggesting the potential role of γδ T cells and IL17 secreting γδ T cells in the pathogenesis of PV. Cytotoxic activity of γδ T cells from PV patients (26±11%) was observed to be higher as compare to control (12±7%). The molecular expression (mRNA) of scavenger receptors CD36 and CD163 were elevated in patients as compared to controls indicating the possible involvement of these PRR along with γδ T cells. These findings may help to understand the pathogenesis of PV and find better approach for novel therapeutics.
BAFF promotes T follicular helper cell development and germinal center generation via BR3 in mice (BA11P.120)
Authors: Zheng Song , Chen Maogen , Li Qiang , Wang Julie , Olsen Nancy 
Published: January 2023

Abstract
BAFF (B cell activating factor belonging to the TNF family) promotes B cells maturation in germinal center. The generation of germinal center depends on T follicular helper cells (Tfh). Overexpression of BAFF and Tfh is found in many autoimmune diseases. However, whether BAFF has effects on Tfh development is still unclear. In this study, we have explored the relationship between BAFF and Tfh in mice. Mice were immunized with KLH for the induction of Tfh in vivo. Naive CD4+ T cells were used for Tfh differentiation in vitro. BAFF−/−, BAFF transgenic (Tg), April−/−, BR3−/−, TACI−/−, BCMA−/−, μMT mice, BCL-2 Tg/μMT, BAFF−/−/BCL-2 Tg and TCRβ-/- mice were used for the mechanism studies. Tfh cells, mature B cell and germinal centers were determined. KLH specific IgG levels were measured by ELISA. The expression of IL-6 and IL-21 was determined by qPCR. We showed that BAFF but not April promotes the development of Tfh cells in vivo and in vitro. Furthermore, the development of Tfh cells is dependent upon BR3, but independent on BCMA and TACI. BAFF facilitates the generation of germinal center, and promotes B cells maturation and secretion of IgG. B cells are required for BAFF-promoted Tfh cell formation. We also demonstrated that BR3 in CD4+ T cells promotes the development of Tfh cells in vivo. In summary, these findings provide evidence that BAFF promotes Tfh development and germinal center generation, and these effects depend upon, at least partially BR3 signal.
Loss of NAPDH oxidase-derived superoxide exacerbates diabetogenic CD4 T cell effector responses (BA11P.122)
Authors: Padgett Lindsey , Anderson Brian , Liu Chao , Piganelli Jon , Mathews Clayton , Tse Hubert 
Published: January 2023

Abstract
In Type 1 diabetes (T1D), infiltrating leukocytes secrete reactive oxygen species (ROS) and pro-inflammatory cytokines that participate in β-cell destruction and enhance T cell autoreactivity. We previously demonstrated that superoxide-deficient Non-obese diabetic (NOD.Ncf1m1J) mice were T1D-resistant due, in part, to blunted Th1 CD4 and cytotoxic CD8 T cell responses. To dissect the role of ROS on autoreactive CD4 T cells, we created the NOD.BDC-2.5.Ncf1m1J (BDC-2.5.Ncf1m1J) mouse with diabetogenic, superoxide-deficient CD4 T cells and hypothesized that reducing ROS would diminish autoreactivity. BDC-2.5.Ncf1m1J splenocytes stimulated with the BDC-2.5 mimotope or islets displayed elevated IFN-γ and pro-inflammatory chemokine ligands CXCL10 and CCL5 (p&lt;0.05). BDC-2.5.Ncf1m1J CD4 T cells were more diabetogenic (p=0.002), with only 26% of transferred NOD.Rag (n=45) mice euglycemic at 10 days post transfer, in contrast to 56% of BDC-2.5-transferred mice (n=24). In vivo suppression assays revealed that enhanced diabetogenicity was due to defective Treg activity, as BDC-2.5.Ncf1m1J Tregs curbed T1D in only 33% of BDC-2.5-transferred NOD.Rag mice (n=9), while BDC-2.5 Tregs induced 70% protection (n=10). Our results highlight the intricate role that ROS induce and restrict T1D autoreactivity. Future studies will dissect the TCR adaptor molecule oxidation status in BDC-2.5.Ncf1m1J CD4 T cells, as these targets may reveal novel biomarkers for T1D progression and prevention.
Mesenchymal stem cell and low level laser therapies reduce T CD4+, CD8+ and PMN cells in lung on experimental model of COPD (CAM4P.144)
Authors: Vitoretti Luana , de Britto Aurélia , da Silveira Elaine , de Moraes Gabriel , Aimbire Flávio , Vieira Rodolfo de Paula , Peron Jean , Ligeiro de Oliveira Ana Paula 
Published: January 2023

Abstract
Chronic Obstructive Pulmonary Disease (COPD) is characterized by airflow limitation, mucus gland hyperplasia, fibrosis and inflammatory cells recruitment into the lung. Cellular and molecular mechanisms of COPD have not yet been elucidated, complicating the use of effective therapies. Low level laser (LLL) and/or mesenchymal stem cell (MSC) are relatively new and effective therapies. We evaluate whether the use of LLL (670 nm, during 15 days) and human tubal-derived MSCs (i.n. 15 and 7 days before euthanasia) could induce changes in polymorphonuclear (PMN) and mononuclear (MN) cells in peribronchial space and T cells in lung of COPD induced mice (submitted to cigarette smoke for 75 days, 2 times/day). We also measured the IL-8 in supernatant of human bronchial epithelial cells (BEC) incubated with 2,5% of cigarette extract, irradiated or not with LLL. Compared to COPD group, we observed less PMN and MN cells in peribronchial space of treated groups, being the association of htMSCs+LLL most effective. The frequency T CD4+ and T CD8+ cells in the lung were significantly reduced irrespective of the therapeutic approach used. For CD8+ T cells, LLL therapy alone seems less efficient than htMSCs alone or in association. We noted reduction of IL-8 levels in BEC supernatant after laser therapy. Other data indicate that the therapies used here could reduce or impair cellular transmigration, T cell activation and cytokines release, being effective to decrease the inflammation in COPD.
CCR2 promotes accumulation of conventional dendritic cells in the lung during inflammation (CAM4P.149)
Authors: Nakano Hideki , Moran Timothy , Nakano Keiko , Whitehead Gregory , Thomas Seddon , Cook Donald 
Published: January 2023

Abstract
Migratory dendritic cells (DCs) take up antigens in peripheral tissues and migrate to tissue-draining lymph nodes (LNs) to present antigen-derived peptides to naïve T cells. Our group recently found that although preDC-derived conventional DCs (cDCs) migrate from the lung to LNs, monocyte-derived DCs (moDCs) do not. It is well established that interactions between the chemokine receptor CCR7 and its ligands direct cDCs from peripheral tissue to LNs, but LNs also contain non-migratory ‘resident’ cDCs derived from preDCs that likely migrate directly from the blood to LNs. We found that these LN resident cDCs are present in CCR7-deficient mice, suggesting that preDC migration from the blood is directed by a different and unknown mechanism. To investigate the mechanism, we used quantitative PCR to study chemokine receptor expression in preDCs. Surprisingly, we found that preDCs express high levels of the gene encoding CCR2, which is primarily recognized as a molecule that directs monocyte trafficking. Ccr2-deficient mice had normal numbers of cDCs in the lung at steady state, but these cells were significantly decreased compared to those of wild-type mice during inflammation. These findings suggest that CCR2 regulates accumulation of preDCs during inflammation, and that a different chemokine receptor directs preDC migration at steady state.
A novel population of myeloid-derived Gr-1+ CXCR2+CD11c+Ly6C+cells expressing FasL and perforin is required for contact hypersensitivity responses (CAM4P.150)
Authors: Kish Danielle 
Published: January 2023

Abstract
Allergic contact hypersensitivity (CHS) is a CD8 T cell mediated response to hapten skin sensitization and challenge. Hapten-primed CD8 cell infiltration into the skin challenge site during elicitation of CHS requires prior infiltration of Gr-1+ CXCR2+ cells expressing FasL and perforin. This study further characterized these Gr-1+ cells. These cells were purified from harvested bone marrow of hapten sensitized and challenged mice by depletion of CD3+, B220+, NK1+, F4/80+, class II MHC+ and Ly6G+ cells. Flow cytometry analyses indicate &gt;90% of the remaining bone marrow cells are FasL+, CD11c+, Ly6C+, CXCR2+, CCR2+, CX3CR1+ and express perforin and granzyme B. These cells are at low numbers in the bone marrow of naïve mice but increase to peak numbers 2 hrs. after hapten challenge of sensitized WT and Rag-/- mice and T-cell depleted WT mice. Generation of these myeloid cells is inhibited by anti-TNFa mAb. Transfer of these myeloid-derived cells from WT donors restores the absent CHS-response in sensitized gld/perforin-/- mice and induces expression of the T cell chemoattractants CCL1, CCL2, and CCL5 in the skin 3-6 hrs after challenge. These results describe a novel population of myeloid cells expressing FasL and perforin/granzyme B that are generated in the bone marrow following hapten challenge of sensitized mice and are activated to induce expression of the chemoattractants directing hapten-primed T cell infiltration into the hapten challenged skin site to mediate CHS.
CCR2 mediated inflammation and gut microbiota in promoting intestinal cancer (CCR5P.214)
Authors: Jala Venkatakrishna , Bodduluri Sobha , Chilton Paula , Bodduluri Haribabu 
Published: January 2023

Abstract
Colorectal cancer is strongly associated with inflammation accompanied by increased infiltration of leukocytes. CCR2/CCL2 axis plays an important role in recruitment of several immune/inflammatory cells. Elevated expression of CCL2 in tumor cells is very well correlated with increased metastasis and poor prognosis in several types of human cancers including colon cancer. Gut microbiota plays an important role in modulating colon tumorigenesis. However, interactions between chemokines-microbiota-colon tumorigenesis are remains to be determined. Our data demonstrated that CCR2-/- mice in the ApcMin/+ (a spontaneous intestinal tumor mouse model) background showed substantial survival advantage compared to ApcMin/+ mice. CCR2-/-ApcMin/+ mice developed significantly fewer and smaller size small intestinal and colon tumors. Further, polyps in CCR2-/-ApcMin/+ displayed decreased tumor infiltrating F4/80+ cells, decreased inflammatory molecules (e.g., IL-1β, SOCS1), increased apoptosis and CD8+ T cells compared to ApcMin/+ mice. Interestingly, inflammatory cytokines IL-23 and IL-17 were significantly reduced in CCR2-/-ApcMin/+. Gut microbiota analysis revealed that tumor promoting Bacteroides genus are significantly reduced in CCR2-/-ApcMin/+ mice compared to ApcMin/+ mice. These data suggests that CCR2/CCL2 mediated recruitment of tumor-associated macrophages (TAMs) and Th17 cells modulate inflammation and microbiota in the tumor microenvironment to promote intestinal tumorigenesis.
Intracerebroventricular TWEAK (TNF-like weak inducer of apoptosis) induces depressive-like behavior and cognitive dysfunction in non-autoimmune mice (CCR5P.200)
Authors: Wen Jing , Chen Chris , Stock Ariel , Doerner Jessica , Burkly Linda , Gulinello maria , Khodakhah Kamran , Putterman Chaim 
Published: January 2023

Abstract
Fn14, the sole receptor for the TNF family member TWEAK, is inducibly expressed in the brain in endothelial cells, astrocytes, microglia, and neurons. Previously, we had found that Fn14 knockout lupus MRL/lpr mice display significantly attenuated neuropsychiatric manifestations. To establish whether this improvement in disease is secondary to ablation of TWEAK-Fn14 signaling within the CNS or the periphery and determine whether TWEAK-mediated neuropsychiatric effects are strain dependent, we performed intracerebraventricular injection (ICV) of Fc-TWEAK or a control protein to B6 mice. Interestingly, we found that the Fc-TWEAK injected mice developed significant depressive-like behavior and abnormal cognitive dysfunction. Inflammatory mediators including MCP-1, C3, and iNOS were significantly elevated in the brains of Fc-TWEAK treated mice. Furthermore, Fc-TWEAK directly increased BBB disruption, as demonstrated by increased fibronectin deposition in the brain and reduced aquaporin-4 expression. Finally, Fc-TWEAK increased apoptotic cell death in the cortex, hippocampus, and brain stem. In conclusion, TWEAK can contribute to lupus-associated neurobehavioral deficits by acting within the CNS to enhance production of inflammatory mediators, promote permeability of the BBB, and induce apoptosis in resident brain cells. Our study provides further support that the TWEAK/Fn14 signaling pathway may be a potential therapeutic target for inflammatory diseases involving the CNS.
Altered innate, adaptive, and TNF-superfamily soluble inflammatory mediators mark impending systemic lupus erythematosus disease flare, while regulatory mediators distinguish lack of impending disease flare in African-American lupus patients (CCR5P.201)
Authors: Munroe Melissa , Vista Evan , Merrill Joan , Guthridge Joel , Roberts Virginia , Air Gillian , Thompson Linda , James Judith 
Published: January 2023

Abstract
SLE is a multifaceted disease characterized by immune dysregulation and varied disease activity. We evaluated changes in plasma soluble mediators (n=52) preceding clinically-defined disease flare, in 13 African American (AA) SLE patients who developed disease flare 6 or 12 weeks after baseline assessment compared to matched SLE patients without impending flare and healthy controls. In addition, mediators within samples preceding SLE disease flare and during a clinically stable period from the same individual were compared in 18 AA SLE patients. Patients with impending flare had significant (q&lt;0.01) alterations in 32 soluble mediators at baseline with significantly higher levels of pro-inflammatory mediators, including innate and adaptive cytokines. Baseline levels of regulatory cytokines, including IL-10 and TGF-β, were higher in non-flare SLE patients, while baseline levels of soluble TNFRI, TNFRII, TRAIL, FasL, and CD40L were significantly greater in pre-flare patients (p&lt;0.05). A normalized and weighted combined soluble mediator score was significantly higher in pre-flare SLE patients versus those with stable disease (p&lt;0.0001). Pro-inflammatory soluble mediators are elevated prior to disease flare, while regulatory mediators are elevated during periods of stable disease. Alterations in the balance between inflammatory and regulatory mediators may help identify AA patients at risk of disease flare and help decipher SLE pathogenic mechanisms.
Functional analysis of protective IL1RL1 variants associated with asthma risk (CCR6P.215)
Authors: Ramirez-Carrozzi Vladimir , Dressen Amy , Lupardus Patrick , Yaspan Brian , Pappu Rajita 
Published: January 2023

Abstract
GWAS studies have identified polymorphisms in both IL33 and IL1RL1, the gene encoding ST2, the high affinity chain of the IL-33 receptor, that associate with asthma susceptibility. We identified amino acid changing variants in IL1RL1 associating with asthma incidence and found these SNPs to be protective from asthma risk in our study population. These variants result in coding changes to the intracellular region of ST2, which contains the TIR domain of the receptor that is critical for signaling downstream of IL-1 cytokine family and TLRs. Mutations or deletions to this region can inhibit ligand-induced responses. IL-33-mediated dimerization of ST2 and IL-1RAcP promotes TIR-TIR domain interaction and recruitment of the adaptor molecule MyD88 leading to AP-1 and NF-kB activation. IL-33 responses were diminished in cell lines expressing all 4 IL1RL1 missense variants. To further elucidate how this haplotype could affect IL-33 activity, we compared IL-33 activity and ST2 expression between donors carrying either haplotype. We observed reduced IL-33 mediated IL-8 secretion from purified blood eosinophils derived from individuals carrying the protective haplotype. We also observed greater soluble ST2 expression in these individuals. Our results provide a link between the genetic predisposition to asthma and IL-33 mediated responses. Given IL-33 promotes Th2 immunity, perturbations that diminish this response may provide protection from asthma risk.
The effects of TNF-a on T cell homeostasis in obese and diabetic mice (CCR6P.219)
Authors: Barba Cindy , Mendoza German , Park Christa 
Published: January 2023

Abstract
Obesity is a growing epidemic in the United States that leads to many complications, including exacerbation of colitis and diminished immune response. Obesity increases levels of TNF-a systemically, causing chronic inflammation. This inflammation suppresses gd-T lymphocytes in epithelial tissues, which play key roles in tissue repair through the release of growth factors and activation of macrophages. Our previous research shows that blocking TNF-a for four days prior to wounding can help improve T cell function. This research focuses on how TNF-a affects intestinal epithelial T cells, splenic T lymphocyte homeostasis, and TNF-a function in obesity. Our study used mice deficient in TNFR1 and TNFR2 to investigate the changes imposed by an absence of TNF-a signaling. Data collected from splenic T cells and small intestine were compared to provide us with insight to the local and peripheral effects of mice with and without TNFR1 and TNFR2. Our current data suggest that TNFR1 and TNFR2 deficient obese mice show a decreased number of splenic T lymphocytes. Wound repair remains dysfunctional in obese mice even in the absence of TNFR1 and 2 suggesting epithelial T cells require TNFR signaling for normal function. The results thus far suggest that TNF-a is an essential cytokine in maintaining the homeostasis and function of T lymphocytes in obese mice. Further research will be conducted involving TNF-a and its receptors on the immune cells of obese and diabetic individuals.
Dual CCR2/CCR5 antagonism by Cenicriviroc efficiently inhibits both MCP-1 and RANTES induced chemokine receptor internalization in murine pro-inflammatory monocytes (CCR6P.221)
Authors: Byron Mary Margaret , D'Antoni Michelle , Premeaux Thomas , Lefebvre Eric , Ndhlovu Lishomwa 
Published: January 2023

Abstract
Persistent immune activation, driven in part by monocytes and macrophages (MO), has been implicated in HIV-associated comorbidities and progressive liver disease. Binding of chemokines MCP-1 and RANTES to their respective chemokine receptors (CKR), CCR2 and CCR5, selectively regulates the migration of MO. Cenicriviroc (CVC), an oral, dual CCR2 and CCR5 antagonist, has completed Phase 2b development in HIV and is undergoing Phase 2b evaluation in subjects with non-alcoholic steatohepatitis (NASH) and liver fibrosis. We assessed CVC receptor occupancy, measured by inhibition of MCP-1 and RANTES induced CKR internalization, compared to single antagonists BMS-22 (CCR2) and Maraviroc (MVC; CCR5) in pro-inflammatory (CD11c+F4/80+Ly6c+) MO in male BALB/c mice (n=6) by flow cytometry and quantified using Molecules of Equivalent Soluble Fluorochrome microspheres. CVC significantly reduced both MCP-1 induced internalization of CCR2 (p&lt;0.01) and RANTES induced internalization of CCR5 (p&lt;0.01). Doses of 0.25-1μM achieved &gt;90% CCR2 and CCR5 occupancy by CVC compared to 49% CCR2 occupancy by BMS-22 and 69% CCR5 occupancy by MVC in blood pro-inflammatory MO. Doses of 0.02-1μM achieved &gt;85% CCR2 and CCR5 occupancy by CVC compared to 72% CCR2 occupancy by BMS-22 and 73% CCR5 occupancy by MVC in spleen pro-inflammatory MO. These data suggest that CVC leads to efficient CCR2 and CCR5 target coverage in blood and tissues with effective doses lower than that of respective single CKR antagonists.
CCR4 is required for efficient thymocyte medullary entry and central tolerance induction (HEM7P.230)
Authors: Ehrlich Lauren , Hu Zicheng , Lancaster Jessica , Sasiponganan Chayanit 
Published: January 2023

Abstract
Clonal deletion of auto-reactive thymocytes is essential for the establishment of central tolerance. The thymic medulla is a specialized microenvironment in which post-positive selection thymocytes are screened for reactivity against a wide range of self-antigens. Autoreactive cells are tolerized via clonal deletion or differentiation into the regulatory T cell lineage. Both thymic dendritic cells (DCs) and medullary thymic epithelial cells (mTECs) present auto-antigens to thymocytes to induce central tolerance. Thus, it is critical that post-positive selection thymocytes enter the medulla and interact efficiently with antigen-presenting cells therein to avoid export of autoreactive naïve T cells. We previously demonstrated that although CCR7 is required for medullary accumulation of thymocytes, additional GPCRs must be involved in medullary entry. Here we report that CCR4 is expressed by post-positive selection thymocytes, while CCR4 ligands are expressed by thymic DCs. Using two-photon time-lapse microscopy, we find that CCR4 is required for accumulation of post-positive selection thymocytes in the medulla, as well as efficient interactions between thymocytes and medullary DCs. In the absence of CCR4, thymocytes fail to undergo clonal deletion to low avidity antigens, autoreactive naïve T cells accumulate in secondary lymphoid organs, and autoimmunity ensues. Taken together, these data demonstrate an essential role for CCR4 in the establishment of thymic central tolerance.