bluuebunny/crossref_metadata_2025_split huggingface dataset:
De Novo Autoimmunity to Cardiac Myosin After Heart Transplantation and Its Contribution to the Rejection Process
Authors: Fedoseyeva Eugenia V. , Zhang Feng , Orr Patricia L. , Levin David , Buncke Harry J. , Benichou Gilles 
Published: January 2023

Abstract
Allograft rejection is initiated by an immune response to donor MHC proteins. We recently reported that this response can result in breakdown of immune tolerance to a recipient self Ag. However, the contribution of this autoimmune response to graft rejection has yet to be determined. Here, we found that after mouse allogeneic heart transplantation, de novo CD4+ T cell and B cell autoimmune response to cardiac myosin (CM), a major contractile protein of cardiac muscle, is elicited in recipients. Importantly, CM is the autoantigen that causes autoimmune myocarditis, a heart autoimmune disease whose histopathological features resemble those observed in rejected cardiac transplants. Furthermore, T cell responses directed to CM peptide myhcα 334–352, a known myocarditogenic determinant, were detected in heart-transplanted mice. No responses to CM were observed in mice that had received an allogeneic skin graft or a syngeneic heart transplant, demonstrating that this response is tissue specific and that allogeneic response is necessary to break tolerance to CM. Next, we showed that sensitization of recipient mice with CM markedly accelerates the rejection of allogeneic heart. Therefore, posttransplant autoimmune response to CM is relevant to the rejection process. We conclude that transplantation-induced autoimmune response to CM represents a new mechanism that may play a significant role in cardiac transplant rejection.
Helminth- and Bacillus Calmette-Guérin-Induced Immunity in Children Sensitized In Utero to Filariasis and Schistosomiasis
Authors: Malhotra Indu , Mungai Peter , Wamachi Alex , Kioko John , Ouma John H. , Kazura James W. , King Christopher L. 
Published: January 2023

Abstract
Infants and children are routinely vaccinated with bacillus Calmette-Guérin (BCG) in areas of the world where worm infections are common. Because maternal helminth infection during pregnancy can sensitize the developing fetus, we studied whether this prenatal immunity persists in childhood and modifies the immune response to BCG. Children and newborns living in rural Kenya, where BCG is administered at birth and filariasis and schistosomiasis are endemic, were examined. T cells from 2- to 10-year-old children of mothers without filariasis or schistosomiasis produced 10-fold more IFN-γ in response to mycobacterial purified protein derivative than children of helminth-infected mothers (p &lt; 0.01). This relationship was restricted to purified protein derivative because maternal infection status did not correlate with filarial Ag-driven IL-2, IFN-γ, IL-4, or IL-5 responses by children. Prospective studies initiated at birth showed that helminth-specific T cell immunity acquired in utero is maintained until at least 10–14 mo of age in the absence of infection with either Wuchereria bancrofti or Schistosoma haematobium. Purified protein derivative-driven T cell IFN-γ production evaluated 10–14 mo after BCG vaccination was 26-fold higher for infants who were not sensitized to filariae or schistosomes in utero relative to subjects who experienced prenatal sensitization (p &lt; 0.01). These data indicate that helminth-specific immune responses acquired during gestation persist into childhood and that this prenatal sensitization biases T cell immunity induced by BCG vaccination away from type 1 IFN-γ responses associated with protection against mycobacterial infection.
Cytolytic T Lymphocytes Recognize an Antigen Encoded by MAGE-A10 on a Human Melanoma
Authors: Huang Lan-Qing , Brasseur Francis , Serrano Alfonso , De Plaen Etienne , van der Bruggen Pierre , Boon Thierry , Van Pel Aline 
Published: January 2023

Abstract
From melanoma patient LB1751, cytolytic T lymphocytes (CTL) were generated that lysed specifically autologous tumor cells. To establish whether these CTL recognized one of the Ags that had previously been defined, a CTL clone was stimulated with cells expressing various MAGE genes. It produced TNF upon stimulation with target cells expressing MAGE-A10. The Ag was found to be nonapeptide GLYDGMEHL (codons 254–262), which is presented by HLA-A2.1. This is the first report on the generation of anti-MAGE CTL by autologous mixed lymphocyte-tumor cell culture (MLTC) from a melanoma patient other than patient MZ2, from whom the first MAGE gene was identified. MAGE genes are expressed in many tumors but not by normal tissues except male germline cells and placenta, which do not express HLA molecules. Therefore, the identification of an antigenic peptide derived from MAGE-A10 adds to the repertoire of tumor-specific shared Ags available for anti-tumoral vaccination trials.
Human Breast Carcinoma Patients Develop Clonable Oncofetal Antigen-Specific Effector and Regulatory T Lymphocytes
Authors: Rohrer James W. , Barsoum Adel L. , Dyess Donna L. , Tucker J. Alann , Coggin Joseph H. 
Published: January 2023

Abstract
Oncofetal Ag (OFA) is a 44-kDa glycoprotein expressed during early to mid-gestation fetal development and re-expressed as a surface Ag by tumor cells soon after transformation. The Ag is detectable on all types of human and rodent tumors tested, but is undetectable on normal cells. In experimental animals it is autoimmunogenic and induces potentially protective T cell responses both after experimental immunization and during tumor development subsequent to carcinogenic insult. To determine whether this tumor-associated Ag is also immunogenic for human T lymphocytes, breast carcinoma patients’ peripheral blood mononuclear leucocytes were stimulated in vitro with autologous tumor cells in the presence of IL-2, γ-IFN, and IL-6 for 2 wk. The tumor-reactive cells were then restimulated and cloned by limiting dilution, and the clones were analyzed. We established 24, 19, 11, and 16 tumor-reactive clones from the four respective patients. Of those, 4, 6, 4, and 7, respectively, proliferated specifically to purified OFA. Both CD4 and CD8 OFA-specific clones were established, which responded equally well to purified OFA or 32- to 44-kDa immature laminin receptor protein. All were CD3+, TCR-αβ+. All CD4 clones secreted γ-IFN, but neither secreted IL-4 nor IL-10. Both IFN-γ-secreting cytotoxic CD8 clones and IL-10-secreting inhibitory CD8 clones were established. Thus, during human cancer development, the same types of OFA-specific effector and regulatory T cells are induced as during murine T lymphomagenesis.
Cutting Edge: Chronic Intestinal Inflammation in STAT-4 Transgenic Mice: Characterization of Disease and Adoptive Transfer by TNF- Plus IFN-γ-Producing CD4+ T Cells That Respond to Bacterial Antigens
Authors: Wirtz Stefan , Finotto Susetta , Kanzler Stephan , Lohse Ansgar W. , Blessing Manfred , Lehr Hans A. , Galle Peter R. , Neurath Markus F. 
Published: January 2023

AbstractWe generated transgenic mice for STAT-4, a regulatory protein specifically associated with IL-12 signaling, under the control of a CMV promoter. These mice expressed strikingly increased nuclear STAT-4 levels in lamina propria CD4+ T lymphocytes upon systemic administration of dinitrophenyl-keyhole limpet hemocyanin and developed chronic transmural colitis characterized by infiltrates of mainly CD4+ T lymphocytes. The latter cells produced predominantly TNF and IFN-γ but not IL-4 upon activation with αCD3/CD28 or autologous bacterial Ags, consistent with a Th1-type cell response. Furthermore, chronic colitis in STAT-4 transgenic mice could be adoptively transferred to SCID mice by colonic and splenic CD4+ T cells that were activated with Ags from autologous bacterial flora. These data establish a critical molecular signaling pathway involving STAT-4 for the pathogenesis of chronic intestinal inflammation, and targeting of this pathway may be relevant for the treatment of colitis in humans.
Differential Effects of IL-2 and IL-15 on the Death and Survival of Activated TCRγδ+ Intestinal Intraepithelial Lymphocytes
Authors: Chu Ching-Liang , Chen Shih-Shun , Wu Tzong-Shoon , Kuo Szu-Cheng , Liao Nan-Shih 
Published: January 2023

AbstractTCRγδ+ cells are enriched in the intestine mucosa and constitute approximately half of the intestinal intraepithelial lymphocytes (iIEL) in mice. They are likely activated by self and foreign Ags in situ, but little is known about how the activated γδ iIEL are regulated. In the iIEL compartment, IL-2 is produced by activated TCRαβ+ iIEL, and IL-15 message is detected in iIEL and in the epithelial cells. We found surface expression of IL-2 as well as IL-15Rs on activated γδ iIEL, and examined the effects of IL-2 and IL-15 on the survival and death of γδ iIEL during secondary stimulation through TCR. We found that both cytokines supported growth of the restimulated γδ iIEL, but exerted different effects on their survival. A significant higher number of live cells were recovered from the γδ iIEL cultures restimulated in IL-15 than in IL-2. Quantitation of apoptotic cells showed more cell death in the IL-2 group than in the IL-15 group. The cell death was associated with restimulation through TCR and was not caused by insufficient growth factor, thus representing activation-induced cell death. Western blot analyses found no difference in the levels of Bcl-2 and Bax proteins between the two groups. However, the level of Bcl-xL protein diminished with time in the IL-2 group whereas the level was sustained in the IL-15 group, which may contribute to the pro-survival effect of IL-15. These results demonstrated that the survival of activated γδ iIEL is differentially regulated by IL-2 and IL-15.
Regulation of Cell Survival During B Lymphopoiesis: Apoptosis and Bcl-2/Bax Content of Precursor B Cells in Bone Marrow of Mice with Altered Expression of IL-7 and Recombinase-Activating Gene-2
Authors: Lu Liwei , Chaudhury Prosanto , Osmond Dennis G. 
Published: January 2023

AbstractB cell development in mouse bone marrow depends critically upon IL-7. To examine the possible in vivo trophic role of IL-7, we have quantitated apoptosis and Bcl-2 family proteins in populations of phenotypically defined B lineage cells in IL-7-deficient and IL-7-overexpressing mice. Using immunofluorescence labeling, multiparameter flow cytometry, and a short-term culture assay, we show that the apoptotic rates of precursor B cells, but not of more mature B cells, are enhanced by IL-7 gene deletion, associated with increased intracellular content of Bax and decreased Bcl-2, while, conversely, an IL-7 transgene suppresses precursor B cell apoptosis and produces low Bax and high Bcl-2 levels. During normal B cell development, high Bax/Bcl-2 ratios characterize cells undergoing greatest apoptotic cell death. Pro-B cells in RAG-2−/− mice, all destined to abort, show elevated Bax levels and Bax/Bcl-2 ratios. By comparison with the elevated rate of pro-B cell apoptosis in RAG-2−/− mice, provisional estimates have been made for the fraction of pro-B cells undergoing apoptosis in normal mice (70%), IL-7−/− mice (85%), and IL-7 transgenic mice (35%). The results demonstrate that IL-7 strongly promotes in vivo cell survival and maintains antiapoptotic Bcl-2/Bax ratios during the development of precursor B cells in mouse bone marrow.
Use of Antagonist Peptides to Inhibit In Vitro T Cell Responses to Par j1, the Major Allergen ofParietaria judaicaPollen
Authors: De Palma Raffaele , Wu Shenhong , Sallusto Federica , Di Felice Gabriella , Martucci Paola , Geraci Domenico , Colombo Paolo , Troise Costantino , Sacerdoti Guido , Nocera Arcangelo , Gorski Jack 
Published: January 2023

AbstractAntigenic peptides with substituted side chains inhibit immune responses to a number of recall Ags from infectious agents in vitro. Here we show that the same strategy can be applied to peptides derived from a pollen protein, the major allergen of Parietaria judaica(Par j1), a plant responsible for most allergenic sensitization in the southern Mediterranean area. Three T cell lines responding to Par j1 protein were used to identify a stimulatory peptide. Two different monosubstituted altered peptide ligands (APL) were identified that bound to the HLA-DR of the responders, did not stimulate the T cell lines on their own, and decreased the response to subsaturating amounts of the unmodified stimulatory peptide. Most important, these APL were able to inhibit the response of these cell lines to intact Par j1 protein. A third monosubstituted peptide bound to the HLA-DR but did not show inhibitory activity. The two APL had a lower affinity than the unsubstituted peptide for the HLA-DR. The last two observations make MHC blockade an unlikely explanation for the observed effect. These results indicate the action of a specific peptide-mediated antagonism that may be useful in controlling the T cell component of an allergic response.
Calcium-Dependent Activation of TNF Family Gene Expression by Ca2+/Calmodulin Kinase Type IV/Gr and Calcineurin
Authors: Lobo Francis M. , Zanjani Reza , Ho Nga , Chatila Talal A. , Fuleihan Ramsay L. 
Published: January 2023

Abstract
CD40 ligand (L), FasL, and TNF-α are members of the TNF family of cytokines. All are expressed by T lymphocytes shortly after activation but have distinct effector functions. Transcription of these genes can be induced by stimulation of T cells by calcium ionophore alone and requires the calcineurin-dependent transcription factor NF of activated T cells. We have examined a second calcium-dependent signaling pathway, mediated by calcium/calmodulin-dependent kinase IV (CaMKIV) in transcriptional activation of TNF family genes. In reporter gene assays using constructs driven by the promoters of human CD40L, FasL, or TNF-α along with vectors expressing constitutively active CaMKIV and calcineurin, we have demonstrated that each promoter is activated by calcineurin and CaMKIV in a synergistic fashion. Furthermore, specific inhibition of CaMKIV by chemical means and by a dominant negative mutant of CaMKIV impairs the ionomycin-induced activity of all three promoters as well as protein expression of CD40L and TNF-α. Our results indicate that activation of gene expression by calcineurin and CaMKIV is common to members of the TNF cytokine family.
The Orientation and Nature of the Interaction Between Beef Insulin-Specific TCRs and the Insulin/Class II MHC Complex
Authors: Wither Joan E. , Vukusic Brian 
Published: January 2023

AbstractRecent crystallographic studies suggest that TCR interact with peptide/class I MHC complexes in a single preferred orientation. Although similar studies have not been performed for class II-restricted TCR, it has been proposed that T cell recognition of peptide/class II complexes has similar orientational restrictions. This study represents a functional approach to systematic analysis of this question. Twenty-one mutant Aβd molecules were produced by alanine scanning mutagenesis and assessed for their ability to present species variants of insulin to a panel of beef insulin-specific T cell hybridomas with limited TCR α- and/or β-chain sequence differences. We demonstrate that all beef insulin-specific TCR have the same orientation on the insulin/Ad complex, such that the α-chain interacts with the carboxyl-terminal region of the Aβd α-helix, and the β-chain complementarity-determining region 3 interacts with the carboxyl-terminal portion of the peptide, consistent with that observed for crystallized TCR-peptide/class I complexes. Despite this structural constraint, even TCR that share structural similarity show remarkable heterogeneity in their responses to the panel of MHC mutants. This variability appears to result from conformational changes induced by binding of the TCR to the complex and the exquisite sensitivity of the threshold for T cell activation.
Extensive Junctional Diversity in Ig Light Chain Genes from Early B Cell Progenitors of μMT Mice
Authors: Bentolila Laurent A. , Olson Stacy , Marshall Aaron , Rougeon François , Paige Christopher J. , Doyen Noëlle , Wu Gillian E. 
Published: January 2023

Abstract
Nontemplated (N) nucleotide additions contribute significantly to the junctional diversity of all Ag receptor chains in adult mice except Ig light (L) chains, primarily because terminal deoxynucleotidyl transferase (TdT) expression is turned off at the time of their rearrangement in pre-B cells. However, because some Ig L chain gene rearrangements are detectable earlier during B cell ontogeny when TdT expression is thought to be maximal, we have examined the junctional processing of κ- and λ-chain genes of CD45(B220)+CD43+ pro-B cells from μMT mice. We found that both κ and λ coding junctions formed in these B cell precursors were extensively diversified with N-region additions. Together, these findings demonstrate that Ig L chain genes are equally accessible to TdT in pro-B cells as Ig heavy chain genes. Surprisingly, however, the two L chain isotypes differed in the pattern of N addition, which was more prevalent at the λ-chain locus. We observed the same diversity pattern in pre-B cells from TdT-transgenic mice. These results suggest that some aspects of TdT processing could be influenced by factors intrinsic to the sequence of Ig genes and/or the process of V(D)J recombination itself.
Functional Characterization of the Somatic Hypermutation Process Leading to Antibody D1.3, a High Affinity Antibody Directed Against Lysozyme
Authors: England Patrick , Nageotte Roland , Renard Martial , Page Anne-Laure , Bedouelle Hugues 
Published: January 2023

AbstractThe impact of somatic hypermutation on the affinity of Abs directed against protein Ags remains poorly understood. We chose as a model the secondary response Ab D1.3 directed against hen egg lysozyme. During the maturation process leading to this Ab, five replacement somatic mutations occurred. After reconstituting the germline Ab from which D1.3 originated, we assessed the energetic and kinetic importance of each of the somatic mutations, individually or combined, using the BIAcore apparatus. We found that the mutations induced an overall 60-fold improvement of affinity, principally due to a decrease in the kinetic rate of dissociation. We showed that their effects were additive and context independent; therefore, in the case of D1.3, the order in which somatic mutations were introduced and selected is unimportant. Interestingly, most of the affinity improvement was due to a single somatic mutation (Asn50→Tyr in VL), involving a residue that belongs to the functional interface between Ab D1.3 and lysozyme. This replacement could either establish new Van der Waals contacts between the Ab and the Ag or help stabilize the conformation of a closely situated crucial residue of the Ab paratope. The four other mutations played only a marginal part in affinity maturation; potential reasons for which these mutations were nevertheless selected are discussed.
IL-12 Administered During Chlamydia psittaci Lung Infection in Mice Confers Immediate and Long-Term Protection and Reduces Macrophage Inflammatory Protein-2 Level and Neutrophil Infiltration in Lung Tissue
Authors: Huang Jin , Wang Ming-Dong , Lenz Stephen , Gao Dongya , Kaltenboeck Bernhard 
Published: January 2023

Abstract
Protection against infections with the intracellular bacterium Chlamydia spp. requires Th1-polarized CD4+ T cell immunity. In BALB/c mouse lung infections, immediate innate and nascent Chlamydia-specific immune responses following intranasal inoculation of Chlamydia psittaci strain B577 were modulated by 7-day i.p. administration of murine rIL-12, the initiation cytokine for Th1 immunity. Treatment with IL-12 reduced the severity of chlamydial pneumonia, abolished mortality (37.5% in untreated mice), and significantly reduced numbers of chlamydial organisms in lungs. On day 4 after inoculation, the neutrophil:macrophage ratio in bronchointerstitial pneumonias was 1.96 in untreated mice and 0.51 in IL-12-treated mice. This immediate, IL-12-mediated shift in innate inflammatory phenotype was correlated with a significant reduction of lung concentrations of the neutrophil chemoattractant macrophage inflammatory protein (MIP)-2 (putative murine homologue of human IL-8), monocyte chemotactic protein-1, and TNF-α; and a reduction in MIP-1α and IFN-γ, at high-dose infection only, and IL-12-independent IL-10 levels. Chlamydia-specific Ab titers and Ig isotype ratios indicated an IL-12-dependent Th1 shift. Recall responses of IL-12-primed mice to secondary chlamydial lung infection eliminated chlamydiae more effectively and generated a lung cytokine profile conducive to perpetuation of the Th1 memory population. These data support the hypothesis that genetic differences in endogenous IL-12 production and response pathways could determine disease outcomes characterized by poor chlamydial clearance and a purulent inflammatory infiltrate vs effective elimination of chlamydiae in a macrophage-dominated response.
Fcγ Receptor-Mediated Activation of Phospholipase D Regulates Macrophage Phagocytosis of IgG-Opsonized Particles
Authors: Kusner David J. , Hall Clifton F. , Jackson Stephen 
Published: January 2023

AbstractReceptors for the Fc portion of IgG (FcγRs) integrate the innate and acquired components of immunity by coupling the specific recognition of IgG Abs to the activation of phagocytic leukocytes. Knowledge of the molecular mechanisms that regulate phagocyte stimulation by FcγRs may permit therapeutic modulation to augment immunoprotective aspects and minimize damage to host tissues in diverse inflammatory diseases. Since phospholipase D (PLD) has been linked to the stimulation of cytotoxic leukocyte responses, we characterized FcγR-dependent activation of PLD in human macrophages. IgG-coated SRBCs (EIgG) stimulated a 9.4-fold increase in PLD activity compared with SRBCs treated with control Ab (p &lt; 0.001), determined by formation of the PLD-specific product phosphatidylethanol in the presence of 0.5% ethanol. Levels of phosphatidic acid, the physiologic product of PLD-mediated catalyzis, were significantly increased in the absence of ethanol (6.4-fold, p &lt; 0.001). PLD activity was also stimulated by immune complex-coated latex beads or cross-linking of Abs specific for FcγRI, FcγRII, or FcγRIII. Phagocytosis of EIgG was reduced by two inhibitors of PLD-mediated signaling, 2,3-diphosphoglycerate or 1-butanol. Addition of purified PLD restored control levels of phagocytosis in cells in which endogenous PLD was inhibited. The tyrosine kinase inhibitors genistein and herbimycin A caused concordant reductions in FcγR-stimulated PLD activity and phagocytosis. These studies demonstrate that FcγR-mediated phagocytosis is accompanied by tyrosine kinase-dependent activation of PLD and support the hypothesis that stimulation of PLD functions to regulate the ingestion of IgG-opsonized particles.