bluuebunny/crossref_metadata_2025_split huggingface dataset:
SLP-2 regulates T cell activation by optimizing cardiolipin compartmentalization in mitochondrial membranes and enhancing cellular respiration (178.7)
Authors: Christie Darah , Elias Isaac , Chau Luan , Lian Dameng , Wang Hao , Ball Eric , Dunn Stanley , Hatch Grant , Madrenas Joaquín 
Published: January 2023

Abstract
Stomatin-like protein 2 (SLP-2) is a mitochondrial protein of the highly conserved Stomatin, Prohibitin, Flotillin, HflC/K superfamily. The function of SLP-2 has remained unclear but members of this superfamily have been linked to membrane organization. We have previously reported that SLP-2 partitions within glycolipid-enriched, detergent-insoluble microdomains, and its expression is up-regulated upon T cell activation. This correlates with increased mitochondrial biogenesis and function. Using human inducible over-expression/down-regulation systems and newly generated T cell-specific SLP-2 knockout mice, we now report that SLP-2 binds directly and selectively to cardiolipin (CL) and interacts with prohibitins. Overexpression of SLP-2 leads to increased recruitment of prohibitins to mitochondrial membranes. This translates into optimal assembly and function of complexes I and II+III of the respiratory chain. SLP-2 deficiency in T cells is associated with abnormal CL compartmentalization and decreased respiration, which correlates with a selective post-transcriptional defect in the production of IL-2 and defective T cell (mostly CD4+) responses. Therefore, we propose that SLP-2 functions as an organizer of cardiolipin-enriched domains in mitochondrial membranes. These domains are required for optimal respiration and metabolic capacity during T cell activation. Our work also reveals a novel post-transcriptional checkpoint for IL-2 production under metabolic control.
Aging is associated with an increase in regulatory T cells, MCP-1 and RANTES (179.13)
Authors: Mansfield Aaron , Nevala Wendy , Dronca Roxana , Leontovich Alexey , Markovic Svetomir 
Published: January 2023

Abstract
We have observed Th2 polarization in patients with metastatic malignant melanoma. We hypothesized that changes in the immune system with age may parallel changes we have seen in patients with cancer. We analyzed the peripheral blood of 389 healthy blood donors. We profiled T cell subsets in 389 of the subjects, and antigen-specific tetramers for CMV, influenza and MART-1 in 58 of the subjects. We used a cytokine multiplex to analyze 42 cytokines in 95 of the subjects. We observed significant increases in CD4+ Th2 cells, and decreases in CD3+ T cells, cytotoxic T cells and helper T cells with age. There were fewer CMV-, influenza- and MART-1- specific naïve and CD8+ T cells with age. There were also significant increases in MCP-1 and RANTES with age. We observed differences between males in females in their cytokine profiles in their 20-40’s but not in their 50-60’s. In summary, we have found that aging is associated with an increase in CD4+ Th2 cells and concomitant decreases in total T cell count, cytotoxic T cells and helper T cells. Furthermore, aging is associated with increases in MCP-1 and RANTES. Females had different cytokine profiles than males before menopause, but not after.
Sequential expression of CD39 regulates late developmental Th17 plasticity imparting a regulatory cell phenotype (179.20)
Authors: Longhi Maria Serena , Bai Aiping , Wu Yan , Strom Terry , Robson Simon 
Published: January 2023

Abstract
Background: CD39 is an immune cell phenotype marker that exhibits ectonucleotidase activity, converting extracellular nucleotides to nucleosides. Although CD39 has been associated with Treg, the ectoenzyme is also expressed by a subpopulation of memory T-cells (CD4mem) with effector functions. We postulate that CD39 imparts plasticity to T helper type 17 (Th17) as well as co-ordinating Treg cellular programs of differentiation. Methods and Results: CD4mem cells were exposed to 1) IL6+IL1β+rTGFβ or 2) IL6+IL1β+IL23 or 3) IL6+IL1β+rTGFβ+IL23 to induce Th17 polarization. Cells were then treated with high dose IL2+anti-CD3/anti-CD28 to favour Treg differentiation and then re-exposed to Th17 differentiating conditions to induce putative reverse or suppressive Th17 (revTh17) cell. Impacts of purinergic mediators on the effector phenotype and functions were assessed. CD4mem could be differentiated sequentially to Th17, Treg and revTh17. In contrast to the inflammatory properties associated with prototypic Th17 cells, revTh17 exhibited a suppressive phenotype. Cells responded in a context-dependent manner to adenosine that boosted revTh17 suppression in the absence of TGFβ. Conclusion: Differential levels of expression of CD39 designate early Th17 cells from later Treg/revTh17 cell plasticity. The potential for Treg to revert to the inflammatory Th17 phenotype is mitigated by expression of CD39, as indicated by enhancements of suppressive function in vitro.
Modulation of T cell receptor and interleukin-2 receptor signaling in human primary CD4+ T cells (179.7)
Authors: Perry Daniel , Thompson James , Han Zhao , Brusko Todd 
Published: January 2023

Abstract
Type 1 Diabetes (T1D) results from the aberrant autoimmune targeting and destruction of insulin-producing β-cells, and dysregulation of T cell activation is central to this break in tolerance. Regulatory T cells (Tregs) are fundamental to maintaining immune homeostasis and functional defects of this T cell subset can potentiate autoimmunity. Therefore, Tregs represent an attractive target for clinical intervention of T1D. Genetic variants of PTPN2 and PTPN22 have been linked to several autoimmune diseases, including T1D, by genome wide association studies. These genes encode for phosphates that dampen IL-2R and TCR signaling, respectively. In this study, we have utilized lentiviral vectors for dual overexpression and knockdown of these genes in primary human CD4+ T cells. We hypothesize that the suppressive function and phenotypic stability of human Tregs is enhanced by increased IL-2R and TCR signaling and deficient following downregulation of IL-2R and TCR signaling. Pathway-modified human effector T cells (Teff) will display altered lineage skewing and may be resistant to AICD and suppression when IL-2R and TCR signaling are increased. Further, simultaneous modulation of these pathways will synergistically affect T cell function. These data will provide insights into how direct modulation of these autoimmune signature pathways controls adaptive Treg and Teff activity, and further, have important implications for adoptive Treg therapy for the treatment of autoimmunity.
TLR2 activation of TRIF controls both early inflammatory and late tolerance responses to Borrelia burgdorferi (180.11)
Authors: Petnicki-Ocwieja Tanja , Chung Erin , Acosta David , Ramos Laurie , Shin Ok , Ghosh Sanjukta , Kobzik Lester , Li Xin , Hu Linden 
Published: January 2023

Abstract
TRIF is an adaptor molecule important in transducing signals from intracellularly signaling toll-like receptors (TLRs) 3 and 4, but not other TLR family members. Recently, TLR2 was found to signal from intracellular compartments. Using a synthetic ligand for TLR2/1 heterodimers as well as the bacterium Borrelia burgdorferi, which causes Lyme disease and is a strong activator of TLR2/1, we found that, contrary to current dogma, TLR2 signaling can utilize TRIF. Unlike TRIF signaling by other TLRs, TLR2-mediated TRIF signaling is dependent on the presence of another adaptor molecule, MyD88. However, unlike MyD88, TRIF deficiency does not result in diminished control of infection with B. burgdorferi. This appears to be due to the effects of MyD88 on phagocytosis via scavenger receptors such as MARCO which are not affected by the loss of TRIF. Although TRIF deficiency is associated with a decrease in pro-inflammatory cytokine induction in vitro, in an animal model of B. burgdorferi infection, loss of TRIF resulted in an increase in IL-6. In vitro studies mimicking longer exposures to B. burgdorferi show that TRIF mediates tolerance to the organism by suppressing pro-inflammatory cytokines disproportionately to anti-inflammatory cytokines in response to long term stimulation. Our studies suggest a dual role for TRIF in early and late TLR2 responses to infectious organisms.
Targeted degradation of DOK3 regulates LPS responses and endotoxin tolerance (180.13)
Authors: O'Loughlin Jason , Peng Qisheng , Humphrey Mary Beth 
Published: January 2023

Abstract
Innate immune activation via Toll-like receptors (TLRs), although critical for host defense against infection, must be regulated to prevent sustained cell activation that can lead to cell death. Cells previously stimulated with lipopolysaccharide (LPS) develop endotoxin tolerance making the cells hypo-responsive to additional TLR stimulation. We investigated the role of downstream of tyrosine kinase 3 (DOK3) in regulating TLR responses and endotoxin tolerance of macrophages and find that DOK3 is a negative regulator of TLR4 and TLR9. Mechanistically, LPS induces ubiquitin-mediated degradation of DOK3 and the Ras activator SOS1, in a DOK3-dependent manner, with subsequent inhibition of ERK activation and repression of IL-1β and IL-10 production. In LPS-induced tolerant macrophages, DOK3 expression remains stable allowing it to sequester SOS1 and Grb2 preventing ERK activation. DOK3-deficient cells demonstrate enhanced sensitivity to LPS and to LPS-induced tolerance becoming tolerant at lower levels of LPS than wild type cells. Additionally, DOK3 negatively regulates several mediators of tolerance including SHIP1, IRAK-M, and SOCS1. Taken together, the absence of DOK3 increases LPS signaling leading to more rapid induction of LPS-induced tolerance. Thus, DOK3 mediates LPS responses and the induction of endotoxin tolerance by a novel mechanism of SOS1 regulation.
A novel TRIF-independent role for the TLR adaptor molecule TRAM during infection with Francisella tularensis. (180.15)
Authors: Morris Ian , Linehan Leslie , Shen Haiqian , Medina Edward , Bergman Molly , Berton Michael 
Published: January 2023

Abstract
The only established function for the TLR adaptor molecule TRAM is as an adaptor linking TLR4 and TRIF to the induction of Type I interferon responses. However, in studies of pulmonary infection with the bacterial pathogen Francisella tularensis (LVS strain), we found that TRAM-/- mice, but not TRIF-/- mice, are more susceptible to F. tularensis infection than WT mice. TRAM-deficient mice exhibited significantly reduced median-time-to-death, increased mortality rate, and a significantly increased bacterial organ burden by days 1-2 after infection compared to WT and TRIF-/- mice. These results are surprising because numerous studies have shown that F. tularensis, despite being Gram-negative, signals the host via TLR2 rather than TLR4. We have also observed a similar increased susceptibility to infection in TRAM-/- mice systemically infected with Listeria monocytogenes. These novel findings suggested that TRAM may function not only in a TLR4 signaling pathway but also as part of a TLR2 pathway. To begin to characterize such a pathway, we expressed a TRAM-GFP fusion protein in macrophages and demonstrated via confocal microscopy that the TRAM-GFP colocalized with TLR2 and F. tularensis upon infection. Moreover, we found that TRAM-TLR2 complexes could be coimmunoprecipitated from TLR2-stimulated macrophages. Collectively, these findings suggest a heretofore unknown role for the TLR adaptor molecule TRAM in TLR2-dependent immune responses.
The omentum is a site of IgM production during T cell-independent bacterial infection in secondary lymphoid organ-deficient mice (43.6)
Authors: Jones Derek , Racine Rachael , Jones Maura , Wittmer Susan , Randall Troy , Winslow Gary 
Published: January 2023

Abstract
Infection of mice with the bacterium Ehrlichia muris results in a T cell-independent (TI) splenic IgM response, and this antibody is secreted largely by a population of CD11c-expressing B cell plasmablasts in the spleen. However, we found that the TI IgM is maintained in the absence of a spleen; infection of splenectomized mice resulted in a modest decrease in antigen-specific serum IgM, indicating that splenic B cells are not required for the generation of the protective antibody response. To identify the source of the IgM-secreting cells, we infected secondary lymphoid organ (SLO)-deficient mice, which lack both spleen and lymph nodes. SLO-deficient mice were similarly able to produce ehrlichia-specific IgM, and both splenectomized and SLO-deficient mice were protected against challenge infection with a lethal ehrlichial species. These findings led us to investigate the omentum as a source of IgM-secreting cells during infection. We identified the omentum as a large reservoir of antigen-specific IgM-secreting cells; these B cells expressed CD11c, but lacked expression of CD138. CD11c-expressing B cells were elicited by intraperitoneal, but not intravenous infection, revealing a route-dependent response to peritoneal antigen. Our data reveal the omentum as an important site of TI IgM production against peritoneal antigens, in the absence of conventional secondary lymphoid organs.
Fli-1 transcription factor directly regulates expression of inflammatory chemokine MCP-1 (44.20)
Authors: Zhang Xian , Suzuki Eiji , Karam Eva , Williams Sarah , Gikeson Gary 
Published: January 2023

Abstract
Fli-1, a member of the Ets family of transcription factors, is highly expressed in immune cells and endothelial cells and is implicated in the development of nephritis in murine models of systemic lupus erythematosus (SLE). Expression of monocyte chemotactic protein-1 (MCP-1) play an important role in the inflammation responses. In this study, we examined the role of Fli-1 on production of MCP-1 in endothelial cells. We found expression of MCP-1 was significantly reduced in endothelial cells isolated from Fli-1 heterozygous knockout NZM2410 mice (Fli1+/-; Fli-1 homozygous knockout is embryonic lethal) after stimulation with Lipopolysaccharides (LPS) compared with endothelial cells isolated from wild-type controls. The expression of Fli-1 protein was significantly reduced and the production of MCP-1 was significantly decreased in endothelial cells transfected with specific Fli-1 siRNA compared to cells transfected with negative control siRNA. We demonstrated that Fli-1 directly binds to the promotor of MCP-1 by Chromatin Immunoprecipitation (ChIP) assay. Our data indicate that transcription factor Fli-1 can binds to the promoter of MCP-1 and directly regulates the expression of inflammatory chemokine MCP-1.
Viral Infection Triggers Rapid Differentiation of Human Blood Monocytes into Dendritic Cells (45.12)
Authors: Hou Wanqiu , Gibbs James , Lu Xiuju , Brooke Christopher , Roy Devika , Modlin Robert , Bennink Jack , Yewdell Jonathan 
Published: January 2023

Abstract
Viruses post a constant threat of human existence. Although human immune system plays a central role in recognizing and eradicating pathogens, how it responds to virus infection remains unclear. Here we show that monocytes make up the majority of a wide variety of virus susceptible population in human peripheral blood mononuclear cells. Notably, infection with influenza virus, vesicular stomatitis virus and vaccinia virus promotes monocytes to differentiate within 18 hours into CD16-negative CD83-positive mature dendritic cells (DCs) with enhanced capacity to activate T cells. Virus-induced monocyte differentiation into DCs does not require cell division, and happens despite the synthesis of virus proteins, suggesting that monocytes thwart the capacity of these highly lytic viruses to hijack host cell biosynthesis pathway. Indeed, virus-induced DC differentiation from monocytes requires infectious virus and viral protein synthesis. Thus, our results demonstrate that monocytes are uniquely susceptible to virus infection among human peripheral blood mononuclear cells, with the likely purpose of differentiating into DCs with enhanced capacity to activate innate and acquired anti-virus immunity.
Involvement of notch in activation of human γδ T cells (45.22)
Authors: Gogoi Dimpu , Chiplunkar Shubhada 
Published: January 2023

Abstract
γδ T cells recognize phosphorylated antigens and play an important role in tumor immunity. The aim of the present study was to investigate the role of Notch signaling pathway in antigen specific responses of γδ T cells. Expression of mRNA for Notch1 and Notch2 genes was predominantly observed in peripheral γδ T cells. The presence of active Notch intracellular domain in γδ T cells was confirmed by confocal microscopy and western blotting. Proliferation of γδ T cells and IFN-γ release in response to phosphoantigens was inhibited in the presence of γ-secretase inhibitor confirming involvement of Notch signal. Delta like ligands 1 and 4 activated γδ T cells while Jagged1 inhibited the γδ T cell response. Oral and breast cancer cells showed dominant expression of Jagged1 ligand which may exert inhibitory signal as a way to evade immune recognition by γδ T cells. Decreased expression of CD107a and diminished lysis of tumor targets in the presence of γ-secretase inhibitor confirmed that Notch was involved in cytotoxic effector functions of γδ T cells. Thus, our data for the first time demonstrates that Notch signal plays an indispensable role in antigen specific responses of γδ T cells. Future immunotherapeutic strategies can exploit Notch signaling in γδ T cells to achieve therapeutic benefits in cancer patients.
Distinct functions of CXCL9/Mig and CXCL10/IP-10 in the priming of tumor-specific IFN-g producing effector T cells (46.2)
Authors: Gorbachev Anton , Kish Danielle , Petro Marianne , Fairchild Robert 
Published: January 2023

Abstract
Major factors limiting immune-mediated elimination of tumors are poor activation and/or insufficient effector functions of tumor-reactive T cells. Chemokines CXCL9/Mig and CXCL10/IP-10 share many anti-tumor functions as potent T cell chemoattractants and angiostatics. However, the individual contribution of each chemokine to the activation of anti-tumor T cell responses remains unclear. Here we tested the role of Mig and IP-10 in the activation of tumor-reactive T cells to the immunogenic murine fibrosarcoma MCA205. Tumor antigen-presenting dendritic cells (DC) deficient in Mig were less potent in activating IFN-g producing MCA205-reactive T cells than were Mig-sufficient DC. In contrast, IP-10-deficient DC were significantly more stimulatory for IFN-g producing tumor-specific T cells than were wild type DC. Activation of tumor-reactive IFN-g producing T cells in tumor hosts was markedly increased in IP-10-/- mice and was decreased in Mig-/- mice when compared to wild type mice. These differences in T cell activation correlated with either accelerated or decreased tumor growth in Mig-/- or in IP-10-/- mice, respectively. In contrast, host DC deficiency either in Mig or in IP-10 did not affect IL-17 producing tumor-specific T cells. These results demonstrate antagonistic functions of Mig and IP-10 during priming of tumor-reactive T cells producing IFN-g and suggest that manipulating the expression of these chemokines by DC can generate more potent anti-tumor immune responses.
Identification and temporal monitoring of breast cancer-associated T cell receptors with high throughput sequencing (46.23)
Authors: Han Jian , Wang Chunlin , Sanders Catherine , Yang Qunying , Byrne-Steele Miranda , Ng Enders , Wong Chris , Kwong Ava , Lu Chiung-Mei 
Published: January 2023

Abstract
Tumor-specific antigens may trigger an immune response that leads to T lymphocytes infiltrating the tumor tissue. We have developed a method to study the immune repertoire of a sample by utilizing a patented multiplex PCR amplification strategy, arm-PCR (Patent No. 7,999,092), coupled with high throughput sequencing (Wang et al., PNAS 2010). Using this method, we studied a patient’s surgically removed breast cancer tissue, the nearby normal tissue, and sorted peripheral blood. The patient’s sorted peripheral blood was also examined three months, six months, and one year post-surgery. Dominant T cell clones with specific CDR3 sequences were identified from the breast cancer tissue. Some of these same clones were found expressed at high levels in the nearby normal tissue and peripheral CD8+ cells. After treatment, dynamic changes in these cancer-associated clones were apparent, demonstrating the capability of the current technology to identify specific T cells associated with a patient’s cancer tissue. These specific T cells can serve as personalized biomarkers for prognosis, treatment evaluations, and early detection of recurrence. They can also be used to develop personalized treatment strategies. Currently, this study has been extended to examine 10 additional breast cancer patients.
Investigating the Role of ERK2 in Peripheral T cells Function Using a Novel Transgenic Mouse Model (47.13)
Authors: Janardhanan Preethi , Quintana Gwendolyn , Byerly Susan , Ji Niannian , Forsthuber Thomas 
Published: January 2023

Abstract
Extracellular signal Regulated Kinase 2 (ERK2) is an important Ser-Thr Kinase involved in MAPK pathway. It is indispensable for early T cell development and is also believed to play a role in T-cell specific antigen recognition signaling, cell proliferation, differentiation, migration and survival. However, it remains unclear how ERK2 regulates peripheral T cell function. Our studies focused on the impact and mechanism of ERK2 deficiency in peripheral T cell activation/function utilizing a mouse model with a conditional ERK2 knockout identified and confirmed by expression of a YFP reporter. Our gene knockout strategy relied on Cre recombinase driven by either distal Lck or inducible promoters. Using flow cytometry analysis/cell sorting and cytokine ELISPOT assay, we have found that T cell activation, survival and cytokine production were impaired in the absence of ERK2. Our results also indicate a role for ERK2 in cell survival in serum starvation and ionomycin/Ca2+ mediated apoptosis. The presented approach will allow us to further investigate the role of ERK2 in other peripheral T cell functions and potentially identify cellular signaling pathways that could be explored for the treatment of CD4+ T cell mediated autoimmune diseases such as MS.
Effect of filgrastim (recombinant human granulocyte colony stimulating factor) on IgE responses in human asthma (48.1)
Authors: Smith-Norowitz Tamar , Kohlhoff Stephan , Ginsburg David , Norowitz Kevin , Joks Rauno , Chice Seto , Durkin Helen , Bluth Martin 
Published: January 2023

Abstract
Rationale: The role of peripheral blood progenitor cell mobilization on IgE responses has not been studied. Methods: Distributions of blood lymphocytes (CD4+, CD8+, CD8+CD60+, CD19+, CD23+, CD16/56+, CD25, CD45RA+, CD45RO+, CD34+), and levels of serum immunoglobulins (IgM, IgG, IgA, IgE) were studied in an allergic asthmatic serum IgE+ (181 IU/mL) adult (m/45 y/o) donor undergoing routine stem cell mobilization protocol (American Society of Hematology) before (day -30), during (day 4), and after (1 wk post last dose) filgrastim (subcutaneous, 480 mcg, 2qd) treatment (flow cytometry, nephelometry, UniCAP Total IgE Fluoroenzymeimmunoassay). Results: On day 4 of filgrastim treatment, numbers of CD8+CD60+ T cells and CD23+ blood cells dramatically increased (&gt;2 fold); CD34+ cell numbers also increased. One week after treatment, numbers of these cells decreased to pre-treatment levels. On day 4 of treatment, serum IgE levels decreased (&gt;50%). However, one week after treatment, IgE levels approached pre-treatment levels. Conclusions. Filgrastim treatment transiently increases numbers of CD8+CD60+ T cells known to regulate human IgE responses (Smith-Norowitz, et al., JI, 2008), while also transiently suppressing ongoing IgE responses. These results suggest that filgrastim might be useful in modulating allergic responses.