bluuebunny/crossref_metadata_2025_split huggingface dataset:
Autoantibodies to ribosomal P antigens with immune complex glomerulonephritis in SJL mice treated with pristane.
Authors: Satoh M , Hamilton K J , Ajmani A K , Dong X , Wang J , Kanwar Y S , Reeves W H 
Published: December 2022

Abstract
BALB/c ByJ mice develop a lupus-like syndrome characterized by anti-nRNP/Sm and Su autoantibodies and immune complex glomerulonephritis after a single i.p. pristane injection. In contrast, mercuric chloride induces anti-fibrillarin Abs only in SJL and other H-2s mice, and not in BALB/c (H-2d) mice. In the present study, the specificities of autoantibodies induced by pristane and HgCl2 were compared in SJL and BALB/c mice to examine whether these strains are "programmed" to make different sets of autoantibodies in response to nonspecific immune stimulation. Unexpectedly, the predominant autoantibodies induced by pristane in SJL mice were neither those characteristic of HgCl2-treated SJL mice nor those associated with pristane-induced disease in BALB/c mice but, rather, anti-ribosomal P, another lupus-related specificity. The autoantibodies were strongly reactive with the C-terminal 22 amino acids of the ribosomal P2 protein, indicating that they exhibited similar fine specificities to anti-P Abs in human SLE and MRL/Ipr mice. Like BALB/c mice, pristane-treated SJL mice developed severe glomerulonephritis characterized by proteinuria, mesangial proliferation, and glomerular immune complex deposits. This is the first evidence that the induction of a lupus-like syndrome by pristane is not restricted to BALB/c mice. The predominance of anti-P Abs in SJL mice contrasts sharply with the predominance of anti-nRNP/Sm and Su, in pristane-treated BALB/c mice, even though the renal lesions were similar in both strains. The data suggest that H-2s does not program mice to produce anti-fibrillarin Abs in response to nonspecific immune stimulation, arguing that autoantibody induction by pristane involves Ag-specific mechanisms.
The catalytic domain of pp56(lck), but not its regulatory domain, is sufficient for inducing IL-2 production.
Authors: Carrera A C , Calvo V , Borlado L R , Paradis H , Alemany S , Roberts T M , Martinez-A C 
Published: December 2022

Abstract
The lymphoid src kinase pp56(lck) has been shown to be essential for the induction of different T lymphocyte responses, including CD4-mediated enhancement of Ag-induced T cell activation, early T cell differentiation, induction of IL-2 production, and cytotoxicity. It is assumed that pp56(lck) acts on these processes by phosphorylating substrates. However, it has been recently reported that the NH2 regulatory domain is sufficient to mediate CD4 accessory function. In this report we address the contribution of the regulatory and catalytic domains of pp56(lck) to another function of this enzyme independent of CD4: TCR-induced IL-2 production. Two pp56(lck) mutants lacking either the entire catalytic domain or the entire NH2 regulatory domain were generated, and their abilities to trigger transactivation of the TCR-regulated nuclear factor of activated T cells (NF-AT) region of the IL-2 promoter were compared. Only the catalytic, but not the NH2 regulatory, domain of pp56(lck) was able to induce NF-AT region transactivation on its own and to cooperate with other intracellular signals to trigger this response. Moreover, the catalytic domain of pp56(lck) was able to induce IL-2 cytokine production to an extent similar to that of wild-type pp56(lck). We conclude that different domains of the pp56(lck) molecule contribute to regulate distinct biologic functions. In fact, while the NH2 regulatory domain is sufficient to mediate CD4 accessory function, we show here that the catalytic domain of pp56(lck) is sufficient for induction of IL-2 production, mimicking TCR ligation.
Overexpression of c-Fos induces apoptosis of CD43+ pro-B cells.
Authors: Hu L , Hatano M , Rüther U , Tokuhisa T 
Published: December 2022

Abstract
The proto-oncogene product c-Fos, a component of the transcription factor AP-1, is induced in early B lineage cells. To investigate a role of c-Fos in early B cell development, fetal liver (FL) cells from transgenic mice carrying an IFN-alphabeta (IFN)-inducible c-fos gene (Mx-c-fosD) were cultured on a stromal cell layer with IL-7. Although B lineage cells normally developed in the Mx-c-fosD FL cell culture, the development was perturbed by the addition of IFN at the beginning of culture. When IFN was added in the FL culture after B lineage cells developed, pro-B (B220+,CD43+) cells were selectively dying by apoptosis within 48 h after IFN stimulation. This apoptosis was intrinsically induced in the pro-B cells that overexpressed c-fos when the Mx-c-fosD FL (H-2Kb) cells were cocultured with the normal C3H FL (H-2Kk) cells. The molecular basis of the apoptosis was investigated by examining expression of the genes that regulate apoptosis. The IFN stimulation did not modulate expression of Bcl-2 and Fas in early B lineage cells from the Mx-c-fosD FL culture. However, Rag-2 was down-regulated in these cells within 12 h after IFN stimulation. These results suggest that the c-Fos plays a causal role in deletion of pro-B cells with nonfunctional Ag receptor.
Apoptosis signaling pathways in normal T cells: differential activity of Bcl-2 and IL-1beta-converting enzyme family protease inhibitors on glucocorticoid- and Fas-mediated cytotoxicity.
Authors: Moreno M B , Memon S A , Zacharchuk C M 
Published: December 2022

Abstract
Fas-mediated apoptosis plays an important role in regulating the immune response in peripheral T cells. Restimulation of T cell blasts up-regulates Fas and Fas ligand expression, with subsequent interaction leading to cell death. Overexpression of Bcl-2 in tumor cells blocks apoptosis induced by many stimuli, but inhibition of Fas-mediated killing has not been consistently observed. To examine the behavior of Bcl-2 in normal cells, T cell blasts were transiently transfected with Bcl-2 and related gene products to determine the effect on apoptotic signaling. Transient overexpression of Bcl-2 in mouse and human T cell blasts did not block Fas-mediated apoptosis, whereas etoposide- and glucocorticoid-induced cytotoxicity was potently inhibited. Expression of Bcl-xL and adenovirus E1B 19K did not interfere with anti-Fas killing. In contrast, interleukin-1beta-converting enzyme family protease inhibitors Ac-DEVD-CHO and CrmA blocked Fas-mediated apoptosis. These results suggest that peripheral T cells use distinct apoptosis signaling pathways with differential sensitivity to Bcl-2 and interleukin-1beta-converting enzyme family protease inhibitors. Since T cells normally express Bcl-2 and Bcl-xL following activation, their inability to block Fas-mediated apoptosis may allow for the elimination of self-reactive cells and the appropriate regulation of immune responses.
Cytotoxic gammadelta or alphabeta T cells with a natural killer cell marker, CD56, induced from human peripheral blood lymphocytes by a combination of IL-12 and IL-2.
Authors: Satoh M , Seki S , Hashimoto W , Ogasawara K , Kobayashi T , Kumagai K , Matsuno S , Takeda K 
Published: December 2022

Abstract
Populations of cytotoxic CD3+CD56+ cells were selectively expanded when monocyte-depleted human PBL (M(-) PBL) were cultured with 20 U/ml IL-12 and 100 U/ml IL-2. In a majority of cases, CD4-CD8- as well as CD8+ gammadelta T cells with CD56 Ag were induced, but in some cases CD4+CD56+ alphabeta T cells were selectively increased. Determination of which will increase, gammadelta or alphabeta T cells, apparently is dependent upon individuals. When M(-) PBL were stimulated with IL-12 and IL-2 in the presence of immobilized anti-CD3 Ab, CD8+CD56+ alphabeta T cells increased exclusively. When M(-) PBL were cultured by IL-2 alone, CD3+CD56- cell expansion was predominant while CD3+CD56+ cells remained a minor population. Cytotoxic activity of M(-) PBL cultured with a combination of IL-12 and IL-2 is much greater than when cultured with IL-2 alone. The cytotoxicity of activated M(-) PBL was abrogated by the depletion of either CD3+ or CD56+ cells irrespective of their gammadelta or alphabeta phenotypes. These types of cells are preferentially present in the livers of humans. The results revealed that, under certain conditions, IL-12 synergizes with IL-2 to induce potent cytotoxic T cells with CD56 Ag of humans, and suggest that these cells in the human liver are functionally similar to NK1+ alphabeta T cells in murine liver.
A mitochondrial membrane protein defined by a novel monoclonal antibody is preferentially detected in apoptotic cells.
Authors: Zhang C , Ao Z , Seth A , Schlossman S F 
Published: December 2022

Abstract
Studies toward the biologic and molecular understanding of programmed cell death have been stimulated by the recent identification of genes and their products that regulate apoptosis. A panel of mAbs has been raised against dying cells in the present study by immunizing mice with apoptotic Jurkat cells. One of these Abs, anti-7A6, was found to react with apoptotic cells. Using ELISA or flow cytometry, little reactivity of anti-7A6 was observed in normal or digitonin-permeabilized human peripheral blood lymphocytes and a number of hemopoietic cell lines tested. The Ab, however, strongly reacted with these cells when they were induced to undergo apoptosis by irradiation or treatment with apoptosis-inducing agents. Cell sorting and DNA fragmentation experiments revealed that 7A6-positive cells, but not 7A6-negative cells, had apparent DNA fragments characteristic of cells undergoing apoptosis. By immunoblot, under reducing conditions, anti-7A6 detected a 38-kDa protein band in the cell lysates prepared from apoptotic cells. Immunoelectron microscopy showed the 7A6 Ag to be localized to the membrane of mitochondria in apoptotic Jurkat cells. These results indicate that anti-7A6 defines a novel epitope on the mitochondrial membrane protein that appears to be exposed on cells undergoing apoptosis, suggesting that the 7A6 molecule may be involved in the molecular cascade of apoptotic cell death.
L-selectin binds to P-selectin glycoprotein ligand-1 on leukocytes: interactions between the lectin, epidermal growth factor, and consensus repeat domains of the selectins determine ligand binding specificity.
Authors: Tu L , Chen A , Delahunty M D , Moore K L , Watson S R , McEver R P , Tedder T F 
Published: December 2022

Abstract
The selectins mediate cellular interactions by binding carbohydrate determinants present on a limited number of glycoprotein ligands. L-selectin binds multiple ligands expressed on endothelial cells, while P-selectin interacts exclusively with P-selectin glycoprotein ligand-1 (PSGL-1) on leukocytes. In this study, L-selectin was shown to bind leukocytes through the P-selectin ligand, PSGL-1, although at lower levels than P-selectin. L-selectin binding to PSGL-1 is specific since it was blocked by Abs to L-selectin or PSGL-1, required appropriate glycosylation of PSGL-1, and was Ca2+ dependent. The contributions of the extracellular domains of the selectins to ligand binding was assessed using a panel of chimeric selectins created by exchange of domains between L-selectin and P- or E-selectin. The lectin and epidermal growth factor domains of L- and P-selectin contributed significantly to binding through similar, if not identical, regions of PSGL-1. The different chimeric selectins revealed that the lectin domain was the dominant determinant for ligand binding, while cooperative interactions between the lectin, epidermal growth factor, and short consensus repeat domains of the selectins also modified ligand binding specificity. L-selectin binding to PSGL-1 expressed by leukocytes may mediate neutrophil rolling on stationary leukocytes bound to cytokine-induced endothelial cells, which was previously reported to be a L-selectin-dependent process.
In the absence of endogenous IFN-gamma, mice develop unimpaired IL-12 responses to Toxoplasma gondii while failing to control acute infection.
Authors: Scharton-Kersten T M , Wynn T A , Denkers E Y , Bala S , Grunvald E , Hieny S , Gazzinelli R T , Sher A 
Published: December 2022

Abstract
The relationship between IFN-gamma and IL-12 in generating innate immune responses and resistance to acute Toxoplasma gondii infection was assessed in T. gondii-exposed IFN-gamma knockout (gko) mice. Gko mice, in contrast to wild-type (wt) animals, rapidly succumbed to infection with either the avirulent ME49 strain or, surprisingly, an attenuated temperature-sensitive mutant strain, ts4. Microscopic examination of peritoneal exudates from infected gko mice demonstrated that mortality is associated with unchecked tachyzoite replication. Nevertheless, both wt and gko animals developed a peritoneal inflammatory response that in gko animals was greater due to a 5- to 10-fold increase in the number of granulocytes recruited to the site of infection. In addition, IL-12 production in gko mice was both unimpaired and functional since a significant, albeit lower than wt, IL-12-dependent NK cell response developed in these animals. Regardless, no evidence for an IFN-gamma-independent protective function for IL-12 or NK cells was apparent since in vivo treatment of gko mice with an IL-12-neutralizing mAb ablated the NK cell response, but did not decrease survival. Together, these data identify distinct functions for IL-12 and IFN-gamma in host resistance to T. gondii: IL-12 precedes and initiates synthesis of IFN-gamma, while the latter lymphokine directly controls parasite growth and diminishes the contribution of IL-4- and IL-5-producing T cell subsets.
Constitutive and inducible mechanisms for synthesis and release of cytokines in immune cell lines.
Authors: Baumgartner R A , Deramo V A , Beaven M A 
Published: December 2022

Abstract
We found that production and release of two functionally antagonistic cytokines, TGF-beta and TNF-alpha, were regulated differently in the mast cell, T cell, and macrophage cell lines RBL-2H3, MLA-144, and U-937, respectively. TGF-beta was produced and released constitutively in all three cell lines. When, however, the cell lines were stimulated with Ag, LPS, or calcium ionophore plus PMA, acceleration of release and some additional production of TGF-beta were apparent. In contrast, TNF-alpha was produced and released only when these lines were stimulated. Although neither the glucocorticoid, dexamethasone, nor the protein kinase C inhibitor, Ro31-7549, suppressed constitutive production or release of TGF-beta, these agents inhibited TNF-alpha production and the inducible component of TGF-beta production noted above. The release of these cytokines, whether constitutive or inducible, was dependent on Golgi-processing as indicated by inhibition with brefeldin A. Therefore, although both types of cytokines were processed by Golgi, only TNF-alpha and the inducible component of TGF-beta production were protein kinase C or steroid-regulated processes. These findings suggested that constitutive and inducible pathways exist for production and release of cytokines and that the inducible pathways can be selectively suppressed by pharmacologic agents.
B cells regulate CD40 ligand-induced IL-12 production in antigen-presenting cells (APC) during T cell/APC interactions.
Authors: Maruo S , Oh-hora M , Ahn H J , Ono S , Wysocka M , Kaneko Y , Yagita H , Okumura K , Kikutani H , Kishimoto T , Kobayashi M , Hamaoka T , Trinchieri G , Fujiwara H 
Published: December 2022

Abstract
Although stimulation of freshly isolated murine spleen cells with anti-CD3 mAb or Con A failed to generate IL-12 production, the same cell preparations depleted of B cells produced IL-12. Addition of normal B cells inhibited IL-12 production in a cell number-dependent manner. IL-12 production was dependent on the presence of CD4+, but not of CD8+, T cells, and inhibited by addition of anti-CD40 ligand (CD40L) mAb. Anti-CD3 or Con A stimulation induced CD40L expression only on CD4+ T cells, which was inhibited in the presence of B cells. IL-12 production was also induced by interactions between CD40L-transfected Chinese hamster ovary cells and splenocytes depleted of T and B cells, but not of APC, indicating CD40L-induced IL-12 production by APC. The involvement of CD40 molecules was examined by comparing the ability of cells from CD40-deficient (CD40 -/-) and wild-type mice (CD40 +/+) to produce IL-12. Spleen cells from CD40 -/- and CD40 +/+ mice produced comparable amounts of IL-12 in response to bacterial stimuli. However, the B cell-depleted fraction from CD40 -/- mice failed to produce IL-12 when stimulated with anti-CD3 or Con A or when cocultured with CD40L-expressing Chinese hamster ovary cells. These results indicate that CD40L expressed on activated T cells induces APC to produce IL-12 through CD40/CD40L interaction, but this pathway is competitively inhibited by CD40+ B cells incapable of producing IL-12 upon stimulation with CD40L. Thus, this might represent a novel mechanism underlying the regulation of cell-mediated and humoral immunity.
Role of a C-terminal residue of an immunodominant epitope in T cell activation and repertoire diversity.
Authors: Mikszta J A , Jang Y S , Kim B S 
Published: December 2022

Abstract
In the present study, the extent of heterogeneity in the high responder T cell response to the predominant epitope region of hen egg white lysozyme (HEL46-61) was examined. Through analyses of T cell proliferation and precursor frequency, the C3H T cell response is shown not to be limited to peptides containing the previously defined minimal epitope of residues 52-61, but rather is quite heterogeneous, encompassing much of the 46-61 sequence. Further characterization using a panel of T cell hybridoma clones revealed T cell recognition of diverse minimal epitopes within this region. Interestingly, these T hybridomas could be grouped into three distinct categories based on the ability to respond to peptides with or without the native arginine residue at position 61 (61-required, 61-inhibitory, dual responders). Using analogue peptides containing single amino acid substitutions at position 61, further heterogeneity within these hybridoma groups was identified, suggesting the presence of an extremely diverse T cell repertoire for the epitope region. The charge and/or size of the C-terminal residue appears to be a critical factor for certain clones; replacement of the native arginine residue with aspartic acid or glutamic acid enabled a nonstimulatory ligand to specifically antagonize a T cell hybridoma response. Collectively, these results strongly suggest that the C-terminal residue of the predominant epitope in high responder mice plays a critical role in T cell diversity and activation.
Evidence for altered regulation of I kappa B alpha degradation in human colonic epithelial cells.
Authors: Jobin C , Haskill S , Mayer L , Panja A , Sartor R B 
Published: December 2022

Abstract
The nuclear factor kappaB (NF-kappaB) regulates the transcription of genes bearing the kappaB consensus motif. Transmigration of NF-kappaB from the cytoplasm to the nucleus is regulated by the IkappaB family of inhibitory NF-kappaB-binding proteins. Dissociation of the NF-kappaB-IkappaB complex requires both phosphorylation and degradation of IkappaBs. We demonstrate that IL-1beta induces complete IkappaB alpha degradation in Caco-2 cell lines but not in HT-29, T84, SW-480 transformed cell lines, or native colonic epithelial cells. A similar lack of IkappaB alpha degradation in HT-29 cells followed TNF-alpha and bacterial polymer stimulation. IL-1beta stimulated NF-kappaB nuclear translocation and NF-kappaB-dependent IL-1beta and IL-8 expression in both Caco-2 and HT-29 cells as assayed by electrophoretic mobility shift assay, immunofluorescence, kappaB-luciferase transfection, reverse transcriptase-PCR analysis and ELISA. In HT-29 cells stimulated with IL-1beta, IkappaB alpha was phosphorylated and when cycloheximide blocked new protein synthesis, IkappaB alpha was partially degraded. NF-kappaB cytoplasmic to nuclear transmigration was incomplete and preceded IkappaB alpha degradation in 9T-29 cells, in contrast to complete coordinated NF-kappaB nuclear translocation and IkappaB alpha degradation in Caco-2 cells. Greater sensitivity of HT-29 cells to a calpain inhibitor, as measured by IL-8 secretion, suggested enhanced resistance to IkappaB alpha proteolysis. These data show that IL-1beta induces NF-kappaB activity and expression of NF-kappaB-dependent genes in colonic epithelial cells and suggest altered regulation of IkappaB alpha degradation compared with other cell lineages, which may result in their increased responsiveness to therapeutic blockade.
Ig VH1 genes expressed in B cell chronic lymphocytic leukemia exhibit distinctive molecular features.
Authors: Johnson T A , Rassenti L Z , Kipps T J 
Published: December 2022

Abstract
Prior studies revealed that the leukemic B cells of patients with chronic lymphocytic leukemia (CLL) express a restricted Ig heavy chain variable region gene (VH gene) repertoire. However, this restriction needs to be re-evaluated in light of findings that the repertoire of Ig VH genes used by primary B cells of normal adults is actually more restricted than originally assumed. Because of this, we critically examined the Ig VH1 and VH7 genes expressed by leukemia cells of a random panel of patients with B cell CLL (n = 117). Forty-one (35%) had leukemia cells with functional VH1 gene rearrangements. Of these, the large majority expressed Ig VH1-69 (n = 26; 63%). The remaining leukemia cell samples expressed VH1-2 (n = 4; 10%), VH1-3 (n = 2; 5%), VH1-8 (n = 2; 5%), VH1-18 (n = 1; 2%), VH1-45 (n = 1; 2%), and VH1-46 (n = 5; 12%). Only 1 of the 117 examined (&lt;1%) used Ig VH genes of the VH7 subgroup. We found that certain alleles of the IgVH1-69 locus are favored in CLL. Also, leukemia B cells that express VH1-69 have a distinctive use distribution of D and JH gene segments compared with that of VH1-expressing CLL B cells that do not use VH1-69 or non-neoplastic B cells that express VH1-69. Finally, the average length of the heavy chain third complementarity-determining regions (CDR3) of VH1-69-expressing leukemia cells is significantly longer than that of normal adult B cells that also express Ig encoded by VH1-69 genes. Collectively, this study indicates that the Ig expressed in CLL have distinctive molecular features that are not representative of the Ig expressed by primary B cells of normal adults.
Schistosome egg granulomas and hepatic expression of TNF-alpha are dependent on immune priming during parasite maturation.
Authors: Leptak C L , McKerrow J H 
Published: December 2022

Abstract
Granulomatous inflammation is key to the pathogenesis of many infectious diseases, including hepatic schistosomiasis. The granulomas that form around schistosome eggs trapped in the liver of infected hosts were thought to be induced primarily, if not exclusively, by egg Ags. We now show that the maturation of adult worms, before the production of eggs, primes local immune responses key to granuloma formation. When parasite eggs are injected into the livers of naive animals, only a minimal, nongranulomatous, inflammatory response results. However, if eggs are injected into the livers of mice previously infected with single-sex adult worms, granuloma formation is restored. Granuloma formation is also restored if mice are presensitized with adult worm homogenates or with eggs themselves before egg injection into the liver. These sensitization studies confirm that an Ag or Ags are shared between different stages of the schistosome life cycle and that immune priming by these Ag(s) is necessary for hepatic granuloma formation. Models of infection that isolate the effects of worms from those of eggs confirm that each of these life cycle stages induces a unique pattern of cytokine expression. Hepatic expression of TNF-alpha, a major cytokine signal for granuloma formation, is a reaction to adult worms, not eggs. TNF-alpha may mediate immune priming necessary for granuloma development since injection of purified TNF-alpha alone restores formation of granulomas in the livers of naive mice injected with eggs.