bluuebunny/crossref_metadata_2025_split huggingface dataset:
Natural Killer (NK) T cells subset predominance after irradiation due to Bcl-2 protection against p53 dependent apoptosis (102.15)
Authors: Yao Zhenyu , Liu Yinping , Strober Samuel 
Published: January 2023

Abstract
Previously, we found the percentage of regulatory NK T cells among all T cells in the spleen of mice treated with total lymphoid irradiation (TLI) increased markedly. In the current study, we gave total body irradiation (TBI) to wild type C57BL/6, p53−/− and Bcl-2 transgenic mice, and measured the number of surviving NK T and non NK T cells and their intracellular Bcl-2 levels. In some studies, the turnover rate of cells was examined by BrdU staining. 24 hours after irradiation, the percentage of NK T cells among all T cells had increased from 3% in the untreated controls to 65% in mice given 3,000 cGy. Whereas the number of non NK T cells decreased at least 1000 fold, the number of NK T cells decreased approximately 50 fold. The BrdU incorporation of NK T cells from irradiated mice was markedly reduced as compared to untreated mice, and was similar to that of non NK T cells. A subset of NK T cells (8–13%) and non NK T cells (1–6%) in untreated mice expressed a high level of Bcl-2. After 3,000 cGy, most surviving T cells were Bcl-2hi cells. The number of Bcl-2hi NK T cells decreased by about two fold while the number of Bcl-2hi non NK T cells decreased by about 100 fold. In p53−/− and Bcl-2 transgenic mice, both NKT and non NKT cells showed similar increased resistance to apoptosis after TBI. In addition, in p53−/− mice there was no significant increase in the percentage or decrease in the number of Bcl-2hi cells between NK T and non NK T cells after TBI. Our data indicate that the increased percentage of NK T cells amongst all T cells after irradiation is due to greater radioresistance of NK T cells as compared to non NK T cells. The loss of non-NK T cells is mainly due to the p53-dependent pathway of apoptosis. Almost all surviving NK T cells express the Bcl-2hi phenotype, but constitutive high expression of Bcl-2 alone cannot explain the unique radioresistance of NK T cells.
Exposure to NIMA-like alloantigens induces vigorous in vivo T cell responses in murine neonates (102.17)
Authors: Opiela Shannon Jacqueline , Adkins Becky 
Published: January 2023

Abstract
During early life, fetuses and neonates are exposed to allogeneic non-inherited maternal antigens (NIMA), through the passage of maternal cells and/or molecules across the placenta and in the breastmilk. Currently, it is thought that this early exposure results in the development of tolerance to NIMA. This is manifest in later life as an increased acceptance of grafts expressing the NIMA antigens. However, there also is evidence that exposure to NIMA during early life can lead to priming instead. In a murine model, we have shown that priming of neonates occurs when they are exposed to low doses of NIMA-like alloantigens. As these two possibilities, tolerance or priming, are extremely important for the outcome of transplantation, our lab has been engaged in studies to understand the in vivo responses of early life exposure to low doses of NIMA-like alloantigens. Following exposure, neonates developed both primary and memory cytotoxic responses to alloantigen. These responses were accompanied by vigorous Th1 and Th2 responses that exceeded the responses of adults similarly exposed. Overall, we conclude that exposure to low doses of NIMA-like alloantigens induces the development of robust cytotoxic and cytokine responses in neonates. This suggests that under specific conditions, early exposure to NIMA may lead to highly efficient immunological priming of all arms of T cell adaptive immunity, rather than tolerance.
This work was supported by NIAID grant number R01 AI44923-02 (B.A.)
The activating receptor, NKp30, is important in the interactions between rat natural killer cells and dendritic cells (102.20)
Authors: Wai Lu-En , Su Wei-Wei , Krams Sheri M 
Published: January 2023

Abstract
There is considerable interest in using dendritic cells (DC) to induce transplant tolerance. DC and natural killer (NK) cells have been found to interact in a bi-directional manner. DCs can activate human NK cells to more effectively kill, while NK cells can mediate both maturation and killing of DCs via an NK cell activation receptor, NKp30. NK cells expressing this receptor are elevated post-transplantation prompting us to examine NK cell interactions with DC in a rodent experimental system.
Wildtype and rNKp30-transfected RNK-16 cells (rat NK cell line) were co-cultured with bone marrow-derived DCs (BMDC). There was a significant increase in IFNγ production when rNKp30+, but not rNKp30−, NK cells were co-cultured with both immature and mature BMDCs. This NK-DC interaction required cell contact. Flow cytometric analysis of BMDCs with the rNKp30-Fc fusion protein (as compared to a control Fc fusion protein) indicated the presence of rNKp30 ligand(s) on the surface of DCs. Several tumor cell lines also specifically bound rNKp30-Fc. rNKp30-Fc binding was abolished by pretreatment of the tumor cells with trypsin suggesting the ligand is a protein. Furthermore, we established that the expression level of putative rNKp30 ligands correlated with the ability to activate NK cells, as indicated by the levels of IFNγ. Understanding NK cell interactions with DC may suggest potential new targets for tolerance induction.
NFAT1 in Cord Blood-Derived Human CD4+ T-Cells: Regulatory Implications for Graft vs. Host Disease (102.27)
Authors: Weitzel Richard Patrick , Lesnewski M , Fanning L , Laughlin Mary J 
Published: January 2023

Abstract
Clinical benefits of umbilical cord blood (UCB) grafts include the lower incidence of acute GVHD following allogeneic transplantation. We have previously demonstrated dramatically lower expression of the NFAT1 transcription factor and its associated transcripts and known binding partners in UCB CD4+ cells following primary stimulation when compared to T-cells obtained from adult blood (AB). We hypothesize that NFAT1 and NFAT1-dependent factors play a critical role in the increased proliferation and decreased cytokine production seen in UCB T-cells. We have now demonstrated in vitro via RNAi-mediated knockdown in AB-derived primary T-cells with RT-PCR and Cytometric Bead Assay that expression of a GVHD-promoting, Th1-type cytokine profile is dependent on expression of NFAT1, and that knockdown of NFAT1 results in a transcriptional and cytokine profile similar to that seen in UCB. However, microarray and RT-PCR time point analyses indicate NFAT1 transcripts are not changed in UCB versus AB CD4+ cells. This may suggest a crucial regulatory role for post-translational events which may preferentially occur in UCB-derived T-cells in vivo. Indeed, we have observed ubiquitination of NFAT1 and rapid rescue of NFAT1 expression following treatment with proteasome inhibitor in UCB-derived T-cells in vitro. NFAT1 in UCB CD4+ cells is shown by co-IP to be significantly more ubiquitinated than in AB-derived cells. Overall, our data indicates that regulation of NFAT1 through ubiquitination and proteasomal degradation, and its subsequent downstream effects may constitute a key difference between T-cells of adult and neonatal origin; specifically that this post-translational modification may serve as a method by which UCB-derived T-cells may prevent NFAT1 activity, impacting their allogeneic response.
In Vitro Methotrexate as a Practical Approach to Selective Allodepletion (102.7)
Authors: Mundy Dorothy I. , Sathe Atul , Ortega Sterling , Collins Robert H. , Karandikar Nitin J. 
Published: January 2023

Abstract
Graft-versus-Host Disease (GvHD) is a major cause of transplant-related morbidity and mortality in recipients of allogeneic hematopoietic stem cell transplantation. GvHD is mediated predominantly by alloreactive donor T-cells, therefore selective depletion of the alloreactive cells from the graft may alleviate GvHD, while maintaining other advantages conferred by donor T-cells, such as graft survival, antiviral immunity and graft-versus-leukemia effect. In this study, we evaluated the ability of methotrexate, a clinically approved anti-metabolite drug, to deplete alloreactive T-cells in mixed lymphocyte reactions (MLR). We show that methotrexate potently inhibits the proliferation of alloreactive T-cells in primary in vitro MLR. In addition, re-exposure of methotrexate-treated cells to the same allostimulus, results in a selective inhibition of the alloreactive immune response while the responses to third party allostimuli and viral antigens are preserved. In conclusion, our results provide strong pre-clinical evidence that in vitro treatment with MTX, a practical FDA-approved agent, results in specific allodepletion and may have excellent potential as an effective approach for preventing or minimizing GvHD.
EFFECT OF AGING ON HOST DENDRITIC CELL (DC) NUMBERS AND FUNCTION FOLLOWING HEMATOPOIETIC STEM CELL CONDITIONING REGIMEN (102.8)
Authors: Abu-Arja Rolla F , Park Joon Seong , Wilke Werner W , FAN JI , Schlueter Annette J 
Published: January 2023

Abstract
Graft versus host disease (GVH) incidence and severity increases with older patient age. Host DC are responsible for initiating GVH, likely from activation during transplant conditioning. In this study, young (8–14 wk) and older (12–16 mo) mice were treated with conditioning of lethal irradiation (950–1100 cGy) and assessed 6 h and 18 h later for changes in DC costimulatory molecule expression and cytokine secretion. Older mice had slightly higher numbers of splenic classical DC (cDC; CD11chi Cl II+ B220-) and plasmacytoid DC (pDC; CD11clo Cl IIlo B220+) both before and after irradiation. No differences were observed in CD40, CD80, or CD86 expression between young and older mice, either before or 6 h after irradiation. IL-12, IFN?, and TNF? producing cDC were more numerous in young than in older untreated mice. These cells decreased in young mice and increased in older mice at 6 and 18 h after irradiation. IL-12, IFN?, and TNF? producing pDC were more frequent in older than in young mice prior to irradiation, and both older and young mice had increased frequency of cells producing these cytokines after irradiation. Older mice had a higher frequency of IL-10+ cDC and pDC prior to irradiation. After irradiation, young mice had a higher frequency of IL-10+ cells. These findings indicate the balance of cytokine production in older mice after conditioning with irradiation is shifted to stimulatory rather than suppressive cytokines
Role of Hepatic Kupffer Cells in Inducing T cell Tolerance (128.12)
Authors: You Qiang , Cheng Linling , Ju Cynthia 
Published: January 2023

Abstract
The liver is known to favor the induction of immunological tolerance rather than immunity. Although Kupffer cells (KC) have been indicated to play a role in liver tolerance to allografts and soluble antigens, the mechanisms involved remain unclear. We hypothesized that KC could induce T cell tolerance by acting as ¡°poor¡± antigen presenting cells, as well as an active suppressor of T cell activation. The phenotypes of KC were characterized by flow cytometry. The abilities of KC to activate T cells and to suppress T cell activation induced by spleen dendritic cells (DC) were examined by in vitro proliferation assays using OTII cells. We found that, comparing with DC, KC expressed significantly lower levels of MHCII, B7.1, B7.2, and CD40. This is consistent with our observation that KC were not as potent as DC in eliciting OVA-specific T cell proliferation. More importantly, we found that KC could inhibit DC-induced OVA-specific T cell response. Further investigation of the mechanism involved in such suppression revealed that KC could induce apoptosis of the activated T cells. In summary, our data suggest that KC are ¡°poor¡± stimulators of T cells, and that they can cause tolerance through induction of T cell apoptosis. These findings indicate that KC play a critical role in regulating immune reactions within the liver and contributing to liver-mediated systemic immune tolerance.
Intravenous Administration of MOG35-55 Peptide Inhibits Experimental Autoimmune Encephalomyelitis by Suppressing IL-17/STAT4 Signaling Pathway (128.16)
Authors: Jiang Zhilong , Zhang Guang-Xian , Rostami A.M. 
Published: January 2023

Abstract
Intravenous (i.v.) administration of encephalitogenic peptide can effectively prevent experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. The mechanism underlying the induction of immune tolerance is not fully understood. In this study, we induced i.v. tolerance against EAE by administration of MOG35-55 peptide and determined the role of IL-17/STAT4 signaling pathways in this process. In EAE mice, IL-17 and tyrosine phosphorylated STAT1, STAT3, STAT4, ERK1/2 and NF-κBp65 were highly elevated in spleen cells and spinal cords, while they were significantly inhibited in tolerized mice. Administration of exogenous IL-17 effectively reversed MOG-induced immune tolerance, accompanied by an elevated level of phosphorylated STAT4. IL-17 activated STAT4 in a dose-dependent manner in vitro. CD11b+ cells in tolerant mice were tolerogenic, characterized by suppressed STAT4 activation; adoptive transfer of CD11b+ cells from the tolerized mice effectively delayed onset and reduced the severity of EAE. We conclude that the IL-17/STAT4 signaling pathway is closely related to EAE induction, which is negatively modulated in MOG-induced immune tolerance. These findings have important implications for the development of novel strategies to treat EAE/MS.
Suppressive Role of CD72 in Experimental Autoimmune Encephalomyelitis (128.22)
Authors: Li Daniel H , Creusot Remi , Ousman Shalina S , Fontoura Paulo , Sobel Raymond A , Cao Thai M , Ho Peggy , Youssef Sawsan , Robinson William H , Hong Anita , Steinman Lawrence , Parnes Jane R 
Published: January 2023

Abstract
CD72, a type II transmembrane protein expressed predominantly on B cells, acts as a negative regulator of B cell signaling and activation, and promotes B cell apoptosis through the B-cell receptor. However, whether CD72 plays a role in autoimmunity in vivo is unknown. We found that aged CD72-deficient mice naturally developed lupus-like autoimmune disease. To examine whether CD72 might play a role in multiple sclerosis [MS], we induced experimental autoimmune encephalomyelitis (EAE), a useful animal model for MS, in both wild-type (WT) and CD72-deficient (CD72KO) mice. We found that immunization with MOG (35–55) peptide induced an earlier onset and more severe clinical disease in CD72KO mice than in WT mice. CD72KO B cells had greater capacity for antigen presentation to CD4+ T cells as determined by T cell proliferation. MOG (35–55) immunized CD72KO mice also had higher anti-MOG IgM antibody response in the late phase (Day 35) of disease compared to WT mice. The present results indicate that CD72 may play an important role in the modulation of human autoimmune diseases such as lupus and MS.
Protection against autoimmune arthritis induced by hsp65-mediated tolerance involves enhanced production of both IFN-γ and antigen-specific antibodies (128.23)
Authors: Satpute Shailesh R. , Moudgil Kamal D. 
Published: January 2023

Abstract
Induction of antigen-specific immune tolerance is a desired goal of many therapeutic approaches against autoimmune diseases. Adjuvant arthritis (AA), an animal model of human rheumatoid arthritis (RA), is a Th1-mediated disease and it can be induced in Lewis (LEW) (RT.1l) rats by s.c. injection of heat-killed M. tuberculosis. Arthritic LEW rats raise T cell and antibody responses to mycobacterial heat shock protein 65 (Bhsp65). We employed a novel tolerogenic approach by introducing a Bhsp65-IgG heavy chain gene construct retrovirally ex vivo into B cells and then injecting these cells i.p. into syngeneic recipients. In another approach, we injected LEW rats i.p. with soluble Bhsp65. The former approach was successful in preventing as well as treating ongoing AA, whereas the latter was effective in the prevention. We observed significantly reduced T cell proliferative response to Bhsp65 in rats injected with either Bhsp65-IgG-expressing B cells or soluble Bhsp65 compared to the respective controls. This reduced T cell proliferation was restored by IL-2. Interestingly, there was increased production of IFN-γ by Bhsp65-primed cells in the Bhsp65-treated LEW rats, whereas not much change was observed in IL-10 secretion. The frequency of CD4+FoxP3+ T cells in peripheral blood did not change following tolerization. However, a high level of serum anti-Bhsp65 antibodies was observed in tolerized rats much earlier during the course of AA than that in controls. Regulation of a Th1-mediated autoimmune disease by a pro-inflammatory cytokine (IFN-γ) and the disease-protective attribute of antibodies represent novel aspects of this study. B cell-mediated suppression of established autoimmunity offers a promising approach for the treatment of RA.
(Support: Arthritis Foundation and NIH)
T cell tolerance to AChR, the autoantigen in myasthenia gravis, is mediated primarily by peripheral mechanisms (128.25)
Authors: Williams Earlanda , Stacy Sue , Carlisle Patricia , Infante Anthony , Lenardo Michael , Kraig Ellen 
Published: January 2023

Abstract
In myasthenia gravis (MG), a T-cell dependent antibody response is directed against acetylcholine receptor (AChR) at the neuromuscular junction. To study T cell tolerance, we generated a transgenic mouse in which the TAChRα chain is expressed as a self protein. This transgenic was bred to nude mice and thymus transplants were performed to produce progeny expressing TAChRα in the thymus and/or the periphery (muscle). These mice were immunized with the TAChRα dominant epitope, p146–162, and in vitro proliferation of responding T cells was measured. Since AChR is expressed at low levels in the thymus, it was presumed that central tolerance would be important. However, this was not the case; only mice with peripheral expression of TAChRα showed tolerance (a lack of proliferation). Furthermore, CFSE-labeled TAChR specific T cells from a TCR transgenic were adoptively transferred into TAChR transgenic (tolerizing) and non-transgenic recipients. Following immunization, proliferation of the transferred T cells was lower in the TAChR transgenic host. Moreover, when the TAChR transgene was bred to scurfy mice, progeny lacking Tregs (foxp3−/Y) exhibited an increase in serum anti-TAChR Ig. Autoantibodies were not seen in the foxp3+/Y mice or in mice lacking Aire function (which have defective central tolerance). These results are consistent with a primary role for peripheral tolerance in regulating the response to AChR.
Supported by an APC Subcontract, a UTHSCSA ERC grant and NIH (T32AG021890, T32DE11438).
Mechanism of B-cell mediated tolerance in LPS versus CpG treated cells (128.33)
Authors: Carey Indira , Su Yan , Li Xin , Scott David 
Published: January 2023

Abstract
Our laboratory has developed a gene therapy protocol for B-cell mediated tolerance induction, whose efficacy has been demonstrated in multiple mouse models for human disease, including diabetes, MS, uveitis and hemophilia. We recently found that LPS activated B cells were tolerogenic, whereas those activated with CpG were not. These observations were made in B cells retrovirally transduced to present various experimental antigens, as well as in specific antigen-presenting transgenic B cells. To further elucidate the mechanism of LPS vs CpG action in B-cell mediated tolerance, we examined differential cytokine expression in mouse primary B cells by Real Time PCR and multiplex protein profiling. Since different migration patterns might be associated with B cell activation by LPS versus CpG, we also tracked B cell migration to lymph nodes after activation. While Real Time PCR data suggests that there is no dramatic difference in IL10 mRNA levels between LPS and CpG treated samples, preliminary multiplex protein profiling data indicate that IL10 may be important for tolerance. Interestingly, our results also show that CpG treatment may affect B cell proliferation and migration, compared to LPS. Thus, LPS and CpG treated B cells mediate differential effects on B cell function/fate. These data may explain the activity of B cells exposed to naked DNA vs those that are retrovirally transduced.
(Supported by NIH AI35622)
Monitoring FoxP3 expression in Tolerance to Factor VIII (128.4)
Authors: Skupsky Jonathan , Scott David W. 
Published: January 2023

Abstract
The FoxP3 transcription factor has emerged as a marker for regulatory T cells in the mouse. Our lab has identified a gene therapy based approach that allows us to abrogate the immune response in models for autoimmune diseases and the deleterious immune response in hemophilic patients being treated with factor VIII. Utilizing the FoxP3-GFP knock-in mouse that has been mated to our hemophilic fVIII−/− mouse, we are able to monitor fluctuations in the FoxP3 by flow cytometry. We have observed a relative increase in FoxP3 when tolerance is induced and a relative decrease when an immune response is initiated towards fVIII. We have also developed an in vitro model to follow FoxP3 as it changes in different populations with certain stimuli. Thus, we found that ~75% of CD4+CD25+ cells in a resting population are FoxP3 positive and 12% of all CD4+ cells are FoxP3+. After a single day of stimulation of splenocytes with soluble anti-CD3 antibody, nearly all the CD4+ cells become CD4+CD25+ while less than 6% remain FoxP3+. When presentation of anti-CD3 via Fc receptors is blocked, activation (monitored by CD25 levels) is abrogated, but FoxP3 levels also decrease. While this drop in the frequency of FoxP3 expression in CD4 T cells can be explained in part by the activation of the CD4+CD25− effector cells, we propose that anti-CD3 antibody is also actively diminishing FoxP3 levels in the regulatory T cell population.
Supported by HL061883.
B cells and T regulatory cells regulate spontaneous autoimmune thyroiditis (SAT) in NOD.H-2h4 mice (128.7)
Authors: Yu Shiguang , Braley-Mullen Helen 
Published: January 2023

Abstract
SAT is characterized by infiltration of thyroids by T and B cells. Although B cell-deficient NOD.H-2h4 mice are resistant to SAT, they develop SAT following transient depletion of T reg by anti-CD25. Depletion of T reg does not increase SAT severity in WT mice. WT and B cell deficient mice have similar numbers of CD4+CD25+Foxp3+ T cells, suggesting that T reg in WT and B cell deficient mice may differ in function, or effector T cells of WT mice may be resistant to suppression, i.e. B cells might modulate T reg activity. T reg from WT and B cell-deficient mice did not differ in their expression of surface TGF-β, or in their ability to suppress anti-CD3 induced proliferation, and effector cells from WT and B cell-deficient mice are equally suppressed by T reg. Studies are in progress to determine if T reg from WT and B cell deficient mice differ in their ability to suppress SAT in vivo. To determine if T reg might inhibit SAT in B cell-depleted WT mice, newborn WT mice were given anti-IgM to deplete B cells; half also got anti-CD25 to deplete T reg. B cell-depleted WT mice developed minimal SAT, but after T reg depletion, they develop SAT comparable to unmanipulated WT mice, suggesting that T reg can inhibit SAT in B cell depleted WT mice. Depletion of B cells in adult WT mice using anti-CD20 reduces SAT severity and anti-thyroglobulin antibody. Studies are in progress to determine if T reg depletion can reverse the effects of anti-CD20 on SAT development.
(Supported by Arthritis National Research Foundation, Children′s Miracle Network, and VA Merit Review).