bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of a Tolerizing Tumor Antigen in Peripheral Tissue Does Not Preclude Recovery of High-Affinity CD8+ T Cells or CTL Immunotherapy of Tumors Expressing the Antigen
Authors: Öhlén Claes , Kalos Michael , Hong Doley J. , Shur Aaron C. , Greenberg Philip D. 
Published: April 2014

Abstract
Transgenic (TG) mice were generated selectively expressing the gag protein of Friend murine leukemia virus (FMuLV) in the liver. FMuLVgag is also expressed by the FBL leukemia, and is the immunodominant tumor Ag of the CD8+ T cell response in C57BL/6 mice. gag-TG mice expressing FMuLVgag in the liver were tolerant to the protein and failed to generate a CTL response to either FBL or FMuLVgag. This tolerance reflected anergy rather than deletion, as CTL responsiveness could be recovered after four cycles of in vitro stimulation. Adoptively transferred gag-specific T cells were not anergized in gag-TG recipients, as revealed by antitumor activity in vivo. Also, such T cells did not induce detectable autoimmune injury in gag-TG liver cells. These results suggest that the requirements for a tissue Ag to provide a tolerizing stimulus are distinct from those for being the target of a T cell-mediated autoimmune response and that the requirements for induction and maintenance of peripheral tolerance are distinct for naive and primed T cells. That anergic T cells reactive with tumor-associated Ags can be recovered by repetitive in vitro stimulation and can mediate tumor therapy suggests strategies that use such Ags to generate CTL for adoptive immunotherapy should be further developed.
Isolation of a New Melanoma Antigen, MART-2, Containing a Mutated Epitope Recognized by Autologous Tumor-Infiltrating T Lymphocytes
Authors: Kawakami Yutaka , Wang Xiang , Shofuda Tomoko , Sumimoto Hidetoshi , Tupesis Janis P. , Fitzgerald Ellen , Rosenberg Steven A. 
Published: April 2014

Abstract
Using cDNA expression cloning, a cDNA encoding a novel human melanoma Ag, MART-2 (melanoma Ag recognized by T cells-2), recognized by HLA-A1-restricted CD8+ T cells from tumor-infiltrating lymphocytes (TIL1362) was isolated from an autologous melanoma cell line, 1362 mel. Homologous sequences to the cDNA had been registered in the EST database. This gene encoded an uncharacterized protein expressed ubiquitously in most normal and cancer cells. A mutation (A to G transition) was found in the cDNA obtained from the1362 mel melanoma cell line in the sequences encoding the phosphate binding loop (P-loop) that resulted in loss of the ability to bind GTP. Transfection of NIH-3T3 with the mutated MART-2 did not result in the development of significant foci. By screening 36 various cancer cell lines using single-strand conformation polymorphism, a possible mutation in the P-loop of MART-2 was found in one squamous cell lung cancer cell line, EBC1. The T cell epitope for TIL1362, FLEGNEVGKTY, was identified to be encoded by the mutated sequence of the MART-2 Ag. The mutation substituted glycine in the normal peptide with glutamic acid at the third amino acid of the epitope, which is an important primary anchor amino acid for HLA-A1 peptide binding. The normal peptide, FLGGNEVGKTY, was not recognized by TIL1362, suggesting that this T cell response was specific for the autologous tumor. Although transforming activity was not detected in the NIH-3T3 assay, MART-2 with the mutation in the P-loop may be involved in the generation of melanoma through a loss of GTP binding activity.
Psoriatic Arthritis Joint Fluids Are Characterized by CD8 and CD4 T Cell Clonal Expansions that Appear Antigen Driven
Authors: Costello Patrick J. , Winchester Robert J. , Curran Shane A. , Peterson Karin S. , Kane David J. , Bresnihan Barry , FitzGerald Oliver M. 
Published: April 2014

AbstractThe CD8 αβT cell receptor repertoire in joint fluid of individuals with active psoriatic arthritis contained an average of 32 major oligoclonal expansions in many variable genes of the TCR β chain (BV) families, as shown by β-chain CDR3 length analysis. Interestingly, a small number of oligoclonal expansions were shared between simultaneous samples of joint fluid and blood; however, most expansions found in joint fluid were not identifiable in blood emphasizing the immunologic specificity of the clonal events for the inflamed joint at a given point of time. The CD4 T cell joint fluid repertoire contained fewer and smaller oligoclonal expansions also largely restricted to the joint, suggesting that CD4 T cells participate perhaps by interacting cognitively to generate the CD8 clones. The inferred amino acid sequence of a single CD8 oligoclonal expansion revealed that they usually are composed of one or a few structurally related clones at the amino acid sequence level with β-chains that encode identical or highly homologous CDR3 motifs. These were not shared among patients. Moreover, several clones that encoded the same amino acid sequence were found to be structurally distinct at the nucleotide level, strongly implying clonal selection and expansion is operating at the level of specific TCR-peptide interactions. The findings support a model of psoriatic arthritis inflammation involving extensive and selective Ag, likely autoantigen, driven intra-articular CD4, and CD8 T cell clonal expansions.
Cutting Edge: Reversal of Murine Lupus Nephritis with CTLA4Ig and Cyclophosphamide
Authors: Daikh David I. , Wofsy David 
Published: April 2014

AbstractCyclophosphamide (CTX) prevents progression of nephritis and prolongs survival in (NZB × NZW)F1 (B/W) mice and is used to treat humans with lupus nephritis. To compare the efficacy of CTLA4Ig with CTX and determine whether there is an incremental benefit to combining CTLA4Ig with CTX, we treated B/W mice with CTX, CTLA4Ig, or both agents. In mice with mild renal disease, treatment delayed the onset of proteinuria and prolonged survival in all groups. In mice with advanced renal disease, treatment with both agents reduced proteinuria in 71% of mice, whereas mice treated with either agent alone had no such improvement. Survival was also markedly improved among mice treated with both agents. Thus, combination treatment with CTX and CTLA4Ig is more effective than either agent alone in reducing renal disease and prolonging survival of B/W mice with advanced nephritis. This striking reversal of proteinuria is unprecedented in animal models of SLE.
Gastrointestinal Cells of IL-7 Receptor Null Mice Exhibit Increased Sensitivity to Irradiation
Authors: Welniak Lisbeth A. , Khaled Annette R. , Anver Miriam R. , Komschlies Kristin L. , Wiltrout Robert H. , Durum Scott , Ruscetti Francis R. , Blazar Bruce R. , Murphy William J. 
Published: April 2014

AbstractIL-7 is a critical cytokine in the development of T and B cells but little is known about its activity on nonhematopoietic cells. An unexpected finding was noted in allogeneic bone marrow transplant studies using IL-7 receptor null (IL-7Rα−/−) mice as recipients. These mice exhibited a significantly greater weight loss after total body irradiation compared with wild type, IL-7Rα+/+, mice. Pathological assessment indicated greater intestinal crypt damage in IL-7Rα−/− recipients, suggesting these mice may be predisposed to gut destruction. Therefore, we determined the effect of the conditioning itself on the intestinal tract of these mice. IL-7Rα−/− mice and IL-7Rα+/+ mice were irradiated and examined for lesions and apoptosis within the small intestine. In moribund animals, IL-7Rα−/− mice had extensive damage in the small intestine, including marked ablation of the crypts and extreme shortening of villi following 1500 cGy total body irradiation. In contrast, by 8 days after irradiation, the small intestines of IL-7Rα+/+ mice had regenerated as distinguished by normal villus length and hyperplastic crypts. Following 750 cGy irradiation, IL-7Rα−/− mice had a higher proportion of apoptotic cells in the crypts and an accompanying increase in the pro-apoptotic protein Bak was expressed in intestinal epithelial cells. These results demonstrate the increased radiosensitivity of intestinal stem cells within the crypts in IL-7Rα−/− mice and a role for IL-7 in the protection of radiation-induced apoptosis in these same cells. This study describes a novel role of IL-7 in nonhematopoietic tissues.
The Balance Between CD45RChigh and CD45RClow CD4 T Cells in Rats Is Intrinsic to Bone Marrow-Derived Cells and Is Genetically Controlled
Authors: Subra Jean-Francois , Cautain Bastien , Xystrakis Emmanuel , Mas Magali , Lagrange Dominique , van der Heijden Harry , van de Gaar Marie-Jose , Druet Philippe , Fournié Gilbert J. , Saoudi Abdelhadi , Damoiseaux Jan 
Published: April 2014

AbstractThe level of CD45RC expression differentiates rat CD4 T cells in two subpopulations, CD45RChigh and CD45RClow, that have different cytokine profiles and functions. Interestingly, Lewis (LEW) and Brown Norway (BN) rats, two strains that differ in their ability to mount type 1 and type 2 immune responses and in their susceptibility to autoimmune diseases, exhibit distinct CD45RChigh/CD45RClow CD4 T cell ratios. The CD45RChigh subpopulation predominates in LEW rats, and the CD45RClow subpopulation in BN rats. In this study, we found that the antiinflammatory cytokines, IL-4, IL-10, and IL-13, are exclusively produced by the CD45RClow CD4 T cells. Using bone marrow chimeras, we showed that the difference in the CD45RChigh/CD45RClow CD4 T cell ratio between naive LEW and BN rats is intrinsic to hemopoietic cells. Furthermore, a genome-wide search for loci controlling the balance between T cell subpopulations was conducted in a (LEW × BN) F2 intercross. Genome scanning identified one quantitative trait locus on chromosome 9 (∼17 centiMorgan (cM); log of the odds ratio (LOD) score 3.9). In addition, two regions on chromosomes 10 (∼28 cM; LOD score 3.1) and 20 (∼40 cM; LOD ratio score 3) that contain, respectively, a cytokine gene cluster and the MHC region were suggestive for linkage. Interestingly, overlapping regions on these chromosomes have been implicated in the susceptibility to various immune-mediated disorders. The identification and functional characterization of genes in these regions controlling the CD45RChigh/CD45RClow Th cell subpopulations may shed light on key regulatory mechanisms of pathogenic immune responses.
Differential Regulation of Human Blood Dendritic Cell Subsets by IFNs
Authors: Ito Tomoki , Amakawa Ryuichi , Inaba Muneo , Ikehara Susumu , Inaba Kayo , Fukuhara Shirou 
Published: April 2014

Abstract
Based on the relative expression of CD11c and CD1a, we previously identified subsets of dendritic cells (DCs) or DC precursors in human peripheral blood. A CD1a+/CD11c+ population (CD11c+ DCs), also called myeloid DCs, is an immediate precursor of Langerhans cells, whereas a CD1a−/CD11c− population (CD11c− DCs), sometimes called lymphoid DCs but better known as plasmacytoid DCs, is composed of type I IFN (IFN-αβ)-producing cells. Here, we investigate the effects of IFN-αβ and IFN-γ as well as other cytokines on CD11c+ and CD11c− DC subsets, directly isolated from the peripheral blood, instead of in vitro-generated DCs. IFN-γ and IFN-α, rather than GM-CSF, were the most potent cytokines for enhancing the maturation of CD11c+ DCs. Incubation of CD11c+ DCs with IFN-γ also resulted in increased IL-12 production, and this IL-12 allowed DCs to increase Th1 responses by alloreactive T cells. In contrast, IFN-α did not induce IL-12 but, rather, augmented IL-10 production. IFN-α-primed matured CD11c+ DCs induced IL-10-producing regulatory T cells; however, this process was independent of the DC-derived IL-10. On the other hand, IFN-α by itself neither matured CD11c− DCs nor altered the polarization of responding T cells, although this cytokine was a potent survival factor for CD11c− DCs. Unlike IFN-α, IL-3 was a potent survival factor and induced the maturation of CD11c− DCs. The IL-3-primed CD11c− DCs activated T cells to produce IL-10, IFN-γ, and IL-4. Thus, CD11c+ and CD11c− DC subsets play distinct roles in the cytokine network, especially their responses to IFNs.
CD4 T Cell-Mediated Alloresistance to Fully MHC-Mismatched Allogeneic Bone Marrow Engraftment Is Dependent on CD40-CD40 Ligand Interactions, and Lasting T Cell Tolerance Is Induced by Bone Marrow Transplantation with Initial Blockade of this Pathway
Authors: Ito Hiroshi , Kurtz Josef , Shaffer Juanita , Sykes Megan 
Published: April 2014

AbstractCostimulatory blockade can be used to promote allogeneic marrow engraftment and tolerance induction, but on its own is not 100% reliable. We sought to determine whether one or the other of the CD4 or CD8 T cell subsets of the recipient was primarily responsible for resistance to allogeneic marrow engraftment in mice receiving costimulatory blockade, and to use this information to develop a more reliable, minimal conditioning regimen for induction of mixed chimerism and transplantation tolerance. We demonstrate that a single anti-CD40 ligand mAb treatment is sufficient to completely overcome CD4 cell-mediated resistance to allogeneic marrow engraftment and rapidly induce CD4 cell tolerance, but does not reliably overcome CD8 CTL-mediated alloresistance. The data suggest that costimulation, which activates alloreactive CTL, is insufficient to activate alloreactive CD4 cells when the CD40 pathway is blocked. The addition of host CD8 T cell depletion to anti-CD40 ligand treatment reliably allows the induction of mixed chimerism and donor-specific skin graft tolerance in 3 Gy-irradiated mice receiving fully MHC-mismatched bone marrow grafts. Thus, despite the existence of multiple costimulatory pathways and pathways of APC activation, our studies demonstrate an absolute dependence on CD40-mediated events for CD4 cell-mediated rejection of allogeneic marrow. Exposure to donor bone marrow allows rapid tolerization of alloreactive CD4 cells when the CD40 pathway is blocked, leading to permanent marrow engraftment and intrathymic tolerization of T cells that develop subsequently.
Regulatory and Effector CD4 T Cells in Nonobese Diabetic Mice Recognize Overlapping Determinants on Glutamic Acid Decarboxylase and Use DistinctVβGenes
Authors: Quinn Anthony , McInerney Brigid , Reich Eva P. , Kim Olivia , Jensen Kent P. , Sercarz Eli E. 
Published: April 2014

AbstractThe 524–543 region of glutamic acid decarboxylase (GAD65), GAD65(524–543), is one of the first fragments of this islet Ag to induce proliferative T cell responses in the nonobese diabetic (NOD) mouse model of spontaneous autoimmune diabetes. Furthermore, NOD mice given tolerogenic doses of GAD65(524–543) are protected from spontaneous and cyclophosphamide-induced diabetes. In this study, we report that there are at least two I-Ag7-restricted determinants present in the GAD65(524–543) sequence, each capable of recruiting unique T cell repertoires characterized by distinct TCR Vβ gene use. CD4+ T cells arise spontaneously in young NOD mice to an apparently dominant determinant found within the GAD65 peptide 530–543 (p530); however, T cells to the overlapping determinant 524–538 (p524) dominate the response only after immunization with GAD65(524–543). All p530-responsive T cells used the Vβ4 gene, whereas the Vβ12 gene is preferentially used to encode the TCR of p524-responsive T cell populations. T cell clones and hybridomas from both of these T cell groups were responsive to APC pulsed with GAD65(524–543) or whole rGAD65. p524-reactive cells appeared to be regulatory upon adoptive transfer into young NOD mice and could inhibit insulin-dependent diabetes mellitus development, although they were unable to produce IL-4, IL-10, or TGFβ upon antigenic challenge. Furthermore, we found that i.p. injection with p524/IFA was very effective in providing protection from cyclophosphamide-induced insulin-dependent diabetes mellitus. These data demonstrate that the regulatory T cells elicited by immunizing with GAD65(524–543) are unique and distinct from those that arise from spontaneous endogenous priming, and that T cells to this limited region of GAD65 may be either regulatory or pathogenic.
Cumulative Inhibition of NK Cells and T Cells Resulting from Engagement of Multiple Inhibitory Ly49 Receptors
Authors: Hanke Thomas , Raulet David H. 
Published: April 2014

AbstractInhibitory receptors specific for MHC class I molecules are expressed on partially overlapping subpopulations of NK cells and memory T cells. A central question pertinent to NK cell development and function is how the combinatorial expression of different receptors with distinct class I specificities affects functional recognition. We therefore studied the quantitative effects resulting from class I engagement of multiple inhibitory Ly49 receptors. We used a transgenic mouse model in which all NK cells and T cells express two different Ly49 receptors with shared class I specificity. Comparisons of cells from these mice with cells from single transgenic mice and wild-type mice revealed that Ly49 receptors cumulatively inhibit lymphocyte effector functions. Multiple Ly49 interactions also had a cumulative impact on NK cell development. The findings suggest that the interactions of inhibitory receptors with class I are interpreted quantitatively rather than as on/off switches. They have intriguing implications concerning NK cell tolerance and reactivity toward cells with extinguished expression of a limited number of class I molecules.
CD25+ CD4+ T Cells Regulate the Expansion of Peripheral CD4 T Cells Through the Production of IL-10
Authors: Annacker Oliver , Pimenta-Araujo Ricardo , Burlen-Defranoux Odile , Barbosa Theolis C. , Cumano Ana , Bandeira Antonio 
Published: April 2014

AbstractThe mechanisms by which the immune system achieves constant T cell numbers throughout life, thereby controlling autoaggressive cell expansions, are to date not completely understood. Here, we show that the CD25+ subpopulation of naturally activated (CD45RBlow) CD4 T cells, but not CD25− CD45RBlow CD4 T cells, inhibits the accumulation of cotransferred CD45RBhigh CD4 T cells in lymphocyte-deficient mice. However, both CD25+ and CD25− CD45RBlow CD4 T cell subpopulations contain regulatory cells, since they can prevent naive CD4 T cell-induced wasting disease. In the absence of a correlation between disease and the number of recovered CD4+ cells, we conclude that expansion control and disease prevention are largely independent processes. CD25+ CD45RBlow CD4 T cells from IL-10-deficient mice do not protect from disease. They accumulate to a higher cell number and cannot prevent the expansion of CD45RBhigh CD4 T cells upon transfer compared with their wild-type counterparts. Although CD25+ CD45RBlow CD4 T cells are capable of expanding when transferred in vivo, they reach a homeostatic equilibrium at lower cell numbers than CD25− CD45RBlow or CD45RBhigh CD4 T cells. We conclude that CD25+ CD45RBlow CD4 T cells from nonmanipulated mice control the number of peripheral CD4 T cells through a mechanism involving the production of IL-10 by regulatory T cells.
Cell Surface-Expressed Moesin-Like Receptor Regulates T Cell Interactions with Tissue Components and Binds an Adhesion-Modulating IL-2 Peptide Generated by Elastase
Authors: Ariel Amiram , Hershkoviz Rami , Altbaum-Weiss Idit , Ganor Sharon , Lider Ofer 
Published: April 2014

AbstractThe adhesion of leukocytes to the extracellular matrix (ECM) depends on their responses to variations in the chemotactic signals in their milieu, as well as on the functioning of cytoskeletal and context-specific receptors. Ezrin, radixin, and moesin constitute a family of proteins that link the plasma membrane to the actin cytoskeleton. The surface expression of moesin on T cells and its role in cell adhesion has not been fully elucidated. Recently, we found that IL-2 peptides generated by elastase modified the adhesion of activated T cells to ECM ligands. Here, we further examined the adhesion regulatory effects of EFLNRWIT, one of the IL-2 peptides, as well as the existence and putative function of its receptor on T cells. We found that when presented to T cells in the absence of another activator, the EFLNRWIT peptide induced cell adhesion to vessel wall and ECM components. Binding of a radiolabeled peptide to T cells, precipitation with the immobilized peptide, and amino acid sequencing of the precipitated protein revealed that EFLNRWIT exerts its function via a cell surface-expressed moesin-like moiety, whose constitutive expression on T cells was increased after activation. This notion was further supported by our findings that: 1) anti-moesin mAb inhibited the binding of T cells to the immobilized EFLNRWIT peptide, 2) immobilized recombinant moesin bound the IL-2 peptide, and 3) soluble moesin inhibited the EFLNRWIT-induced T cell adhesion to fibronectin. Interestingly, moesin appears to be generally involved in T cell responses to adhesion-regulating signals. Thus, the IL-2 peptide EFLNRWIT appears to exert its modulating capacities via an adhesion-regulating moesin-like receptor.
Stromal Cell-Derived Factor 1α-Induced Chemotaxis in T Cells Is Mediated by Nitric Oxide Signaling Pathways
Authors: Cherla Rama P. , Ganju Ramesh K. 
Published: April 2014

AbstractStromal cell-derived factor 1α (SDF1α) and its cognate chemokine receptor CXCR4 act as potent chemoattractants and regulate trafficking and homing of hematopoietic progenitor cells and lymphocytes. However, the molecular mechanisms regulating SDF1α-driven cell migration are not well defined. In this study, we have explored the roles of the second messenger NO and the transcription factor NF-κB in SDF1α-induced T cell migration. SDF1α treatment of Jurkat T cells increased the activity of NO synthase, which catalyzes the generation of NO. We observed that pretreatment of Jurkat cells or activated PBLs with several NO donors significantly enhanced the SDF1α-induced migration, whereas various inhibitors of NO synthase markedly abrogated the chemotactic response in a concentration-dependent manner. Furthermore, we observed that inhibitors of the transcription factor NF-κB, which is linked to NO signaling pathways, also significantly blocked the SDF1α-induced chemotactic response. However, these compounds did not have a significant effect on SDF1α-induced mitogen-activated protein kinase activity. In addition, the MAP/Erk kinase kinase inhibitor PD98059 did not abrogate SDF1α-induced chemotaxis. AKT, which has been shown to mediate NO production, was also phosphorylated upon SDF1α stimulation. These studies suggest that NO-related signaling pathways may mediate SDF1α-induced chemotaxis, but not mitogen-activated protein kinase activation.