bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distinct phenotypes of antigen-selected CD8 T cells emerge at different stages of an in vivo immune response.
Authors: Walker P R , Ohteki T , Lopez J A , MacDonald H R , Maryanski J L 
Published: December 2022

Abstract
We have previously described a unique system for identifying Ag-selected CD8 T cells during an in vivo response in normal mice. In this system, lymphocytes isolated from DBA/2 mice injected i.p. with HLA-CW3 transfected syngeneic (H-2d) P815 cells show a remarkable expansion of CD8 cells that utilize TCR expressing the V beta 10 gene segment and additional structural features characteristic of Kd-restricted CW3-specific CTL clones. We have now taken advantage of this system to characterize the surface phenotype of CD8 cells selected by Ag in vivo. We observed several distinct phenotypes at different stages of the response. At the peak of the response, Ag-selected cells were low in CD62L and CD45RB expression but displayed high levels of CD44. In addition, there was a partial down-regulation of CD8 and TCR. Cells of this phenotype were present in lymphoid tissues for several mo after immunization. Much later in the response, Ag-selected cells expressed higher levels of CD8 and TCR. Moreover, a distinct subset of these long-term immune cells emerged that now expressed CD62L and CD45RB. Analysis of CD8 cells from different tissues also revealed certain differences, particularly in TCR and co-receptor levels from liver-derived cells compared with circulating cells at the peak of the response. Our findings suggest that the function of Ag-selected CD8 cells may be regulated over time and according to location by subtle changes in cell-surface phenotype.
Radiation-induced apoptosis is differentially regulated in primary B cells from normal mice and mice with the CBA/N X-linked immunodeficiency.
Authors: Woodland R T , Schmidt M R , Riggs J E , Korsmeyer S J , Lussier A M , Gravel K A 
Published: December 2022

Abstract
Normal B cells responsive to thymus independent-type 1 Ags (TI-1) are resistant to low doses of ionizing radiation in vivo (200-300 cGy), compared with TI-1 responsive B cells of mice with the CBA/N X-linked immunodeficiency (xid). This difference in radiosensitivity is an intrinsic B cell property; normal B cells adoptively transferred into xid mice remain TI-1-responsive after irradiation in situ. Because irradiation induces programmed cell death (PCD) in lymphocytes, we determined whether PCD were regulated differently in normal and xid B cells. B cells isolated immediately after irradiation from normal or xid donors when cultured without stimulators became apoptotic with the same kinetics and to the same extent, showing that apoptosis was induced equally in both populations. Apoptosis could be suppressed and mitogenesis could be induced frequently, however, if irradiated B cells were cultured with B cell activators. When activators using separate signal transduction pathways were compared, a hierarchy of efficiency at effecting apoptosis rescue was observed, and activators used singly without effect could synergize to protect. xid B cells were more resistant to rescue than normal B cells unless PMA was used as a stimulant. Although the mechanism of activator-induced rescue was not established, selective overexpression of a bcl-2 transgene rendered xid B cells radioresistant. The data suggest that a signal(s) delivered to irradiated B cells in the in vivo microenvironment suppresses apoptosis and that xid B cells and a radiosensitive subpopulation of normal B cells are refractory to this signal(s).
Down-regulation of CD8 on mature antigen-reactive T cells as a mechanism of peripheral tolerance.
Authors: Zhang L , Fung-Leung W , Miller R G 
Published: December 2022

Abstract
Previously we have shown that intravenous injection of male B6 lymphocytes containing CD8+ cells into B6 female anti-HY TCR transgenic mice results at 6 wk in the disappearance of the majority of male Ag-reactive T cells (TghighCD8+) from the periphery. Here we investigate the process in more detail. B6 female anti-HY TCR transgenic mice were intravenously injected with viable lymphocytes from male B6 normal, CD4-/-, CD8-/- or CD8-/- carrying a CD8 transgene lacking its cytoplasmic tail ("CD8 tail-less") mice. The fate of TghighCD8+ cells was followed in vivo. There was always a large (at least twofold) expansion of these cells in the periphery 4 days after encountering male Ag. Their subsequent fate differed, however, depending on whether or not the injected male lymphocytes contained normal CD8-expressing cells. If the injected male lymphocytes contained normal CD8 cells, at 6 wk there was a large drop in the number of TghighCD8+ cells associated with a rise in the number of TghighCD8- cells. If the injected male lymphocytes lacked CD8 cells or expressed only tail-less CD8, TghighCD8+ cell numbers returned to normal by 6 wk, while TghighCD8- cell numbers remained unchanged. The TghighCD8- cells, although carrying high levels of the male specific TCR, did not react to male Ag. In addition, their ability to respond in anti-CD3-induced activation, which does not require CD8 as a co-receptor, was significantly impaired. Our data suggest that down-regulation of CD8 on the Ag-reactive T cells accounts, at least partially, for the disappearance of HY-reactive T cells from the periphery. Further, some step in the process requires signaling through the cytoplasmic domain of CD8 on the injected Ag-bearing cells.
Polymorphism at position nine of the MHC class I heavy chain affects the stability of association with beta 2-microglobulin and presentation of a viral peptide.
Authors: Ribaudo R K , Margulies D H 
Published: December 2022

Abstract
To identify residues that control the interactions between MHC-heavy chains and (beta 2m) sequence comparisons were made between murine class I MHC molecules with high (H-2Dd, H-2Kb) and low (H-2Ld, H-2Db) affinities for beta 2m. A single residue at position 9 was evaluated for its contribution to the stability of the complex. Mutagenesis of the glutamic acid at position 9 of H-2Ld to valine, as is found in H-2Dd and H-2Kb, resulted in both qualitative and quantitative effects on inter-chain interactions, intracellular transport, peptide binding, and peptide presentation. In in vitro translation and assembly studies, the E9V mutation resulted in a more stable association of beta 2m with the heavy chain after immunoprecipitation with the alpha 2 domain-specific Ab 30-5-7 in the presence of an H-2Ld-restricted peptide. E9V variant expressed in transfected L cells had similar surface expression compared with H-2Ld despite exhibiting a slower rate of maturation. However, cells expressing E9V were unable to present peptide Ag to a specific T cell hybridoma. H-2LdE9V in E-3 cells, which are defective in TAP-dependent peptide transport, was expressed at higher levels than H-2Ld and was stabilized more efficiently by the addition of exogenous human beta 2m. Thus, amino acid position 9 not only plays an important role in the interaction of the MHC-1 molecule with the beta 2m, it also qualitatively and quantitatively influences peptide binding and Ag presentation.
Lethal shock is inducible by lipopolysaccharide but not by superantigen in mice with retrovirus-induced immunodeficiency syndrome.
Authors: Aoki Y , Hiromatsu K , Arai T , Usami J , Makino M , Ishida H , Yoshikai Y 
Published: December 2022

Abstract
The retrovirus-induced murine AIDS (MAIDS) shares many features with human AIDS. Here, we examined the susceptibility of mice with MAIDS to staphylococcal enterotoxin-triggered shock. Following sensitization with D-galactosamine (D-Gal), mice with MAIDS were resistant to the otherwise lethal effect of superantigen staphylococcal enterotoxin A (SEA). Peak IL-2 levels in these mice after D-Gal/SEA challenge were 10-fold higher than those in uninfected controls, and concurrently, IL-10 levels rose markedly with reduction of circulating IL-1 and IFN-gamma. Treatment with neutralizing anti-IL-10 mAb before D-Gal/SEA challenge led to increased IFN-gamma levels in mice with MAIDS, and resulted in a dose-dependent mortality. In contrast, mice with MAIDS were more susceptible to the toxicity of bacterial endotoxin LPS than were uninfected controls. Administration of 100 micrograms LPS alone induced 50% lethality in mice infected with MAIDS virus 8 wk previously but not in uninfected controls. Administration of 10 micrograms LPS caused acute shock in D-Gal-sensitized mice with MAIDS. Peak TNF-alpha levels in these mice after LPS challenge were increased more than 10-fold, whereas IL-10 levels were one-third of those after SEA challenge. Moreover, serum IFN-gamma was undetectable in uninfected controls and rose to 1063 +/- 483 pg/ml in mice with MAIDS 4 h after LPS challenge. These results suggest that aberrant profiles of cytokine production are crucial in determining fatal outcome in these two types of septic shock in MAIDS.
Metabolic requirements for induction of contact hypersensitivity to immunotoxic polyaromatic hydrocarbons.
Authors: Anderson C , Hehr A , Robbins R , Hasan R , Athar M , Mukhtar H , Elmets C A 
Published: December 2022

Abstract
Experiments were performed to define the metabolic requirements for induction of contact hypersensitivity to polyaromatic hydrocarbons (PAHs), environmental xenobiotics that are both immunotoxic and carcinogenic. Evidence that conversion of the parent compound to a reactive metabolite was necessary for the development of contact hypersensitivity included the fact 1) that contact hypersensitivity to the polyaromatic hydrocarbon dimethylbenz(a)anthracene (DMBA) only occurred in strains of mice that could metabolize the compound, 2) that among the PAHs, only those that could induce aryl hydrocarbon hydroxylase, the rate-limiting enzyme in the PAH metabolic pathway, were immunogenic, and 3) that inhibitors of PAH metabolism reduced DMBA contact hypersensitivity. Cells from the XS52 Langerhans cell-like dendritic cell line were able to metabolize the PAH benzo(a)pyrene to its diol, quinone, and phenol metabolites. GM-CSF augmented benzo(a)pyrene metabolism in XS52 cells. Finally, in vivo depletion of CD8+, but not CD4+, T cell populations inhibited contact hypersensitivity to DMBA. The implications of these experiments are that at least for some contact allergens, the metabolic status of the host is a key determinant of individual susceptibility to the development of allergic contact dermatitis, and the metabolic pathway of an individual hapten may have ramifications for the T cell subpopulation-CD4 or CD8-that is activated.
Selective inhibition of E-selectin, vascular cell adhesion molecule-1, and intercellular adhesion molecule-1 expression by inhibitors of I kappa B-alpha phosphorylation.
Authors: Chen C C , Rosenbloom C L , Anderson D C , Manning A M 
Published: December 2022

Abstract
The promoters of the E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) genes contain recognition sequences for the inducible nuclear transcription factor kappa B (NF-kappa B). We demonstrate that the appearance of NF-kappa B DNA-binding activity in the nucleus of TNF-alpha-stimulated HUVEC is associated with the rapid phosphorylation and subsequent degradation of I kappa B-alpha, the cytoplasmic inhibitor of NF-kappa B. Serine protease inhibitors prevented the TNF-alpha-induced accumulation of phosphorylated I kappa B-alpha, and prevented I kappa B-alpha degradation and the appearance of NF-kappa B DNA-binding activity. These inhibitors had no direct effect upon the ability of NF-kappa B to bind its cognate recognition sequences, nor upon the DNA-binding activities of other transcription factors. Inhibition of I kappa B-alpha proteolysis resulted in the inhibition of the cytokine- and LPS-induced transcriptional up-regulation and cell-surface expression of E-selectin, VCAM-1, and ICAM-1. In contrast, the TNF-alpha-induced expression of plasminogen activator inhibitor-1 and the constitutive expression of ICAM-2 were unaffected. These inhibitors also had no effect on cellular viability or rates of RNA or protein synthesis. Inhibitors of other proteases and various protein kinases had no effect on the cytokine-induced expression of these endothelial adhesion molecules. These findings indicate that it is possible, using a single pharmacologic agent, to selectively inhibit the expression of the E-selectin, VCAM-1, and ICAM-1 genes without affecting the constitutive or inducible expression of other genes. Pharmacologic inhibition of I kappa B-alpha proteolysis represents a novel approach to the development of anti-inflammatory therapeutics.
Contribution of IL-1, CD14, and CD13 in the increased IL-6 production induced by in vitro monocyte-synoviocyte interactions.
Authors: Chomarat P , Rissoan M C , Pin J J , Banchereau J , Miossec P 
Published: December 2022

Abstract
Rheumatoid synovitis is characterized by an infiltration of mononuclear cells and by the proliferation of synoviocytes. Monocytes and synoviocytes are major producers of cytokines, growth factors, and enzymes that contribute to the rheumatoid arthritis (RA) process. Since they are in close contact in vivo, we engaged in an in vitro study of the functional consequences of their interactions. Coculture of unstimulated elutriated normal blood monocytes over RA synoviocytes resulted in a synergistic increase of the production of IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF), leukemia inhibitory factor (LIF), and IL-8, when compared with their respective production in culture alone. In contrast, cytokines such as IL-10, IL-1 beta, IL-1 alpha, and TNF-alpha could not be detected. The IL-6 production in coculture was further increased by the addition of IL-1 beta, GM-CSF, IFN-gamma, or TNF-alpha, but was inhibited by the addition of IL-10, IL-4, IL-13, or IL-1Ra, an effect reverted by the addition of IL-1 beta. Moreover, an inhibition was also observed with anti-CD14 mAb and newly raised mAbs directed against RA synoviocytes. Under reducing conditions, the mAb SY12 precipitated a 150-kDa surface membrane protein, identified as amino-peptidase N (CD13/AP-N). Collectively, these results indicate that 1) monocytes and synoviocytes interact with each other to produce proinflammatory cytokines, 2) pro- and antiinflammatory cytokines have opposite effects on IL-6 production, and 3) molecules such as IL-1, CD14, and CD13 are involved.
Anti-CD3:anti-IL-2 receptor-bispecific mAb-mediated immunomodulation. Low systemic toxicity, differential effect on lymphoid tissue, and inhibition of cell-mediated hypersensitivity.
Authors: MacLean J A , Su Z , Colvin R B , Wong J T 
Published: December 2022

Abstract
An anti-CD3:anti-CD25 (CD3,25) bispecific mAb was developed with the objective of combining the advantages of the parent anti-CD3 and anti-CD25 mAbs. The in vivo effects of the CD3,25 were examined in comparison to the parent Abs. The CD3,25 was well tolerated in vivo, in contrast to the parent anti-CD3 mAb, which induced systemic toxicity in recipient animals. Anti-CD3 mAb induced cell death, lymphoblast formation, and T cell activation in peripheral lymphoid organs; these were observed to a lesser extent in CD3,25-treated animals. In the thymus, anti-CD3 caused a progressive depletion of the CD4+ CD8+ "double positive" thymocytes, which was not seen in CD3,25-treated animals. This finding suggests that monovalent CD3 binding is insufficient to induce thymocyte apoptosis. Animals treated with a combination of anti-CD3 and anti-CD25 mAbs demonstrated changes in the lymphoid organs that were similar to anti-CD3-treated mice. This finding demonstrates that the effect of the CD3,25 is different than the sum of the parent Abs and suggests that the bispecific nature of the CD3,25 results in a reagent with unique immunomodulatory properties. The functional efficacy of the CD3,25 was assessed in a murine model of delayed-type hypersensitivity. The CD3,25 was as effective as the anti-CD3 mAb in inhibiting the delayed-type hypersensitivity reaction and was more effective than the parent anti-CD25 mAb. These data demonstrate that appropriately designed bispecific mAbs can be used as effective immunosuppressive agents with low systemic toxicity.
Peptide-selected T cell lines from myasthenia gravis patients and controls recognize epitopes that are not processed from whole acetylcholine receptor.
Authors: Matsuo H , Batocchi A P , Hawke S , Nicolle M , Jacobson L , Vincent A , Newsom-Davis J , Willcox N 
Published: December 2022

Abstract
To study pathogenic T helper cells in myasthenia gravis (MG) reacting against the acetylcholine receptor (AChR), we have previously selected five CD4+ T cell lines/clones from MG patients (or healthy controls) against full-length recombinant human AChR alpha subunit (alpha 1-437); these can all recognize AChR solubilized from human muscle. Recently, T cells selected with pooled AChR subunit synthetic peptides have shown greater heterogeneity than above. Hoping to validate that, we have characterized three MG and six control T cell lines selected with pooled peptides (averaging 33 residues long) covering the alpha subunit sequence; recurring responses to three particular peptides each showed preferred HLA class II restrictions--p75-115/DR4, p138-167/DR4, and p309-344/DR3 (or DR52a). However, none of three lines from MG patients recognized p138-167--even one from a previous responder to this epitope in full-length alpha 1-437; otherwise they resembled those from controls. Moreover, no peptide-selected line responded significantly to whole AChR, alpha 1-437, or even to shorter polypeptides sharing one terminus with the peptide, suggesting specificity for epitopes not naturally processed by APCs from blood. Of 20 sublines maintained with individual peptides, at least 10 responded to independently synthesized overlapping sequences, but four others depended on contaminants in the original peptides. A single line did recognize one longer polypeptide, but only after tryptic digestion; the processing of this cryptic epitope was evidently the limiting factor here rather than its concentration or the T cell sensitivity. Therefore, while synthetic peptides are essential for mapping epitopes, assessment of the pathogenic MG T cell repertoire requires full-length Ag processed naturally.
Activation of telomerase in human lymphocytes and hematopoietic progenitor cells.
Authors: Hiyama K , Hirai Y , Kyoizumi S , Akiyama M , Hiyama E , Piatyszek M A , Shay J W , Ishioka S , Yamakido M 
Published: December 2022

Abstract
This is the first report describing up-regulation of telomerase activity in human normal cells. Telomerase, a ribonucleoprotein enzyme, has been thought to be involved in maintaining telomere length stability in germline and most cancer cells, but not in normal cells. However, in the present study, we demonstrate that telomerase activity is detectable at low levels in normal human T and B cells, increases by in vitro mitogenic stimulation, increases in hematopoietic progenitor cells upon their proliferation and differentiation, and decreases with aging. Understanding the regulation of telomerase activity in normal cells may provide important insights not only into the mechanisms of normal cellular senescence but also into the mechanisms of telomerase activity deregulation as part of cancer development.
Opposing effects of TGF-beta 2 on the Th1 cell development of naive CD4+ T cells isolated from different mouse strains.
Authors: Hoehn P , Goedert S , Germann T , Koelsch S , Jin S , Palm N , Ruede E , Schmitt E 
Published: December 2022

Abstract
The development of naive dense CD4+ T cells from different mouse strains toward Th1 cells, as monitored by measuring secondary IFN-gamma production, was affected by TGF-beta 2 in a differential way. Th1 cell development of naive CD4+ T cells from strains C57Bl/6, BALB/c, and NMRI primed by immobilized anti-CD3 mAb was strongly inhibited in the presence of TGF-beta 2. Even when the Th1 cell-inducer IL-12 was added, the same effect of TGF-beta 2 was observed. In contrast, Th1 development was substantially promoted by TGF-beta 2 with T cells from C3H/He and CBA/J mice. Further analyses using CD4+ T cells from (C57Bl/6xCBA/J)F1 hybrids or DBA/1 mice showed that Th1 development was inhibited by TGF-beta 2 if the T cells were activated by anti-CD3 mAb, but it was enhanced upon costimulation with anti-CD28 mAb. Determination of primary IL-2 production revealed that T cells from (C57Bl/6xCBA/J)F1 and DBA/1 mice produced low amounts of IL-2 following stimulation by anti-CD3 mAb alone and comparatively high amounts after coactivation by anti-CD28 mAb. In the presence of TGF-beta 2, the production of IL-2 was completely suppressed if such T cells were activated solely by anti-CD3 mAb, but it was only partially inhibited after costimulation by anti-CD28 mAb. Furthermore, TGF-beta 2-promoted Th1 development of such T cells was strongly inhibited after neutralization of endogenously produced IL-2 and completely restored by the addition of human IL-2. Thus, our results indicate that the TGF-beta 2-mediated stimulation of Th1 cell development requires the presence of relatively high concentrations of IL-2. Therefore, the opposing effect of TGF-beta 2 on the Th1 cell development of naive CD4+ T cells from different mouse strains appears to be the result of the variable potency of the respective CD4+ T cells to produce IL-2 in the presence of TGF-beta 2.
T cell-dependent secretion of IL-1 beta by a dendritic cell line (XS52) derived from murine epidermis.
Authors: Kitajima T , Ariizumi K , Mohamadazadeh M , Edelbaum D , Bergstresser P R , Takashima A 
Published: December 2022

Abstract
IL-1 beta has been reported to play an essential role in the induction of T cell-mediated immune responses in skin, and Langerhans cells are considered to be the primary source of IL-1 beta in epidermis. We have established recently a long-term dendritic cell line (XS52) from mouse epidermis. This line resembles resident epidermal Langerhans cells in many respects, including the potent capacity to present a protein Ag (KLH) to a CD4+ Th1 clone (HDK-1) and the expression of IL-1 beta mRNA. We sought to determine whether XS52 cells secrete IL-1 beta upon Ag-dependent interaction with T cells and, if so, to elucidate the mechanism. Despite constitutive expression of mRNA for both IL-1 beta and the IL-1 beta-converting enzyme (ICE), XS52 cells secreted no detectable IL-1 beta spontaneously. When they were cultured with HDK-1 T cells and KLH, relatively large amounts of IL-1 beta (17.5-kDa form) were detected in the culture supernatant. IL-1 beta was secreted by LPS-stimulated XS52 cells, but not by LPS- or Con A-stimulated HDK-1 cells, suggesting that IL-1 beta is secreted primarily by XS52 cells in the coculture system. Incubation with HDK-1 cells alone or with KLH alone caused no IL-1 beta secretion, indicating the requirement for both T cells and Ag. IL-1 beta secretion was associated with a striking up-regulation of IL-1 beta mRNA and a modest up-regulation of ICE mRNA and enzymatic activity. IL-1 beta secretion was blocked by Ac-YVAD-CHO (a peptide inhibitor of ICE), CTLA4-Ig fusion protein, or anti-Ia mAb. IL-1 beta secretion was triggered in a T cell-independent manner by either CTLA4-Ig or anti-Ia mAb in immobilized forms. Thus, the XS52 dendritic cell line secretes, by an ICE-dependent mechanism, biologically relevant amounts of IL-1 beta upon Ag-dependent interaction with T cells, with both Ia molecules and B7-related molecules playing essential roles.