bluuebunny/crossref_metadata_2025_split huggingface dataset:
CD30 defines a subset of activated human T cells that produce IFN-gamma and IL-5 and exhibit enhanced B cell helper activity.
Authors: Alzona M , Jäck H M , Fisher R I , Ellis T M 
Published: December 2022

Abstract
CD30 is a lymphoid activation Ag expressed by activated B and T lymphocytes, as well as selected lymphoid malignancies. In T cells, CD30 expression is limited to a minority (15 to 25%) of activated CD45RO+ T cells. Studies were undertaken to define unique functional properties of CD30+ T cells by identifying the profile of cytokine production by CD30+ T cells, and by assessing their ability to provide help for B cell Ig production. Assessment of cytokine mRNA transcripts by reverse transcription-PCR (RT-PCR) revealed the presence of IFN-gamma mRNA transcripts only in CD30+ T cells derived from FACS purified from activated CD45RO+ T cells. IFN-gamma mRNA was present neither in the CD30- subset of activated CD45RO+ T cells, nor in activated CD45RA+ T cells. Both CD30+ and CD30- subsets expressed IL-10 and IL-2R alpha mRNAs after 3 days of activation, but neither population expressed IL-4 or IL-6 transcripts at this time. Furthermore, production of secreted IFN-gamma was significantly greater in activated CD30+CD45RO+ cells (564 +/- 250 pg/ml) than in CD30-CD45RO+ (50 +/- 33 pg/ml) or CD45RA+ (0 +/- 0) T cells. CD30+ T cells also expressed IL-5 mRNA and secreted significantly higher levels of IL-5 (320 +/- 73) than activated CD30-CD45RO+ (17 +/- 5) T cells. In contrast, CD30- T cells produced significantly higher levels of IL-2 than CD30+ T cells (1270 +/- 380 vs 450 +/- 128). Induction of IFN-gamma in CD30+ T cells was not a result of CD30 engagement by Abs used during the isolation process, although an anti-CD30 Ab (M44) known to exert agonist activity was capable of inducing IFN-gamma production by T cells when immobilized to plastic. Finally, CD30+CD4+ T cells exhibit significantly greater helper activity for B cell Ig production than CD30-CD4+ T cells. These results demonstrate that CD30 identifies a unique subset of T cells that comprise the major IFN-gamma- and IL-5-producing cells in the T cell compartment, and exhibit potent helper activity for B cell Ig production.
Spontaneous production of granulocyte colony-stimulating factor in vitro by human B-lineage lymphocytes is a distinctive marker of germinal center cells.
Authors: Corcione A , Baldi L , Zupo S , Dono M , Rinaldi G B , Roncella S , Taborelli G , Truini M , Ferrarini M , Pistoia V 
Published: December 2022

Abstract
The ability of human B lymphocytes to produce granulocyte (G)-CSF in vitro was investigated. Highly purified tonsillar B cells were fractionated into large and small cells by a Percoll density gradient, cultured, and tested for G-CSF gene expression. Large B cells spontaneous produced G-CSF mRNA and protein, whereas small B cells did not, even after incubation with various stimuli. Immunophenotypic analyses showed that large B lymphocytes contained approximately 60 to 70% of cells with the characteristic surface markers of germinal center (GC) B cells (CD38+, CD10+, and surface IgG+). The remaining cells expressed CD39, CD23, and surface IgD and were presumably in vivo-activated follicular mantle zone B cells. Fractionation of the large B lymphocytes into CD39+, surface IgD+, and CD39-, surface IgD- cells showed that the latter, but not the former, cell type produced G-CSF spontaneously in culture. Stimulation of purified (CD39-, surface IgD-) GC B cells with a CD40 mAb alone or in combination with IL-4 increased G-CSF production. Because these stimuli rescued a large fraction of GC cells (up to 50%) from spontaneous apoptosis in vitro, the finding may suggest that prevention of apoptotic death resulted in an increased G-CSF production or that CD40 mab and/or IL-4 increased G-CSF gene expression in G-CSF-producing GC B cells. Malignant B cells purified from the invaded lymph nodes of three patients with follicular center cell lymphoma and three Burkitt lymphoma cell lines, which had an immunophenotype identical with that of normal GC B cells, spontaneously produced G-CSF in vitro, thus confirming the GC origin of the cytokine. Incubation of normal purified GC B cells with rG-CSF resulted in the rescue of GC B cells from apoptosis, suggesting that G-CSF may be used by GC B cells in an autocrine manner. This autocrine loop of production and response to G-CSF by GC B cells may be activated by stimuli such as those delivered via the surface CD40 molecule, that participate in the rescue of GC B cells from apoptosis.
gp120 ligation of CD4 induces p56lck activation and TCR desensitization independent of TCR tyrosine phosphorylation.
Authors: Goldman F , Jensen W A , Johnson G L , Heasley L , Cambier J C 
Published: December 2022

Abstract
HIV gp120 binding to CD4 suppresses TCR function. The molecular mechanism of this anergizing effect is incompletely understood. Studies reported here reveal that CD4 ligation initiates p56lck activation and renders human peripheral T cells and HPB-ALL cells hyporesponsive to Ag receptor stimulation, as indicated by the failure of TCR binding ligands to induce either protein tyrosine phosphorylation or elevation of intracellular-free calcium concentration. To approach the possibility that p56lck-mediated tyrosine phosphorylation of specific sites within TCR zeta-chain might be involved in the gp120-induced TCR signaling defect, we tested the kinase's ability to phosphorylate various zeta peptides. Kinetics analyses indicate that peptides derived from the in vitro autophosphorylation site of p56lck Y394 and two sites within zeta, Y84, and Y152, are equally effective substrates for p56lck, whereas p56fyn prefers a substrate peptide derived from a different site within zeta, Y142. Although these data are consistent with the possibility that gp120-mediated signal disruption of TCR could be due to p56lck phosphorylation of Y84 and Y152 residues within zeta, further experiments revealed that gp120 does not induce detectable zeta tyrosine phosphorylation under conditions in which it disrupts TCR signaling. These data indicate that gp120 can induce uncoupling of TCR from the earliest events in signal transduction and that this effect can be mediated by a mechanism other than tyrosine phosphorylation of TCR zeta-chain.
Imposing deviant immunity on the presensitized state.
Authors: Kosiewicz M M , Okamoto S , Miki S , Ksander B R , Shimizu T , Streilein J W 
Published: December 2022

Abstract
Delayed hypersensitivity (DH) is an important immune effector modality that successfully wards off intracellular pathogens and many parasites, but also causes immunopathogenic injury to vital tissues. Particularly in the eye, DH has devastating effects that can lead to blindness. Ags injected into the anterior chamber of the eye of naive mice elicit a deviant form of systemic immunity in which DH is selectively down-regulated. Expression of DH in this model system is curtailed by regulatory CD8+ T cells. At present, we have determined whether injection of Ag into the anterior chamber of eyes of specifically sensitized mice also impairs DH expression. Our results indicate that DH is blunted or eliminated in previously primed mice when heterologous proteins, retinal autoantigens, or minor histocompatibility Ags are injected into the anterior chamber. Suppression is achieved in this system by Ag-specific CD8+ T cells, and failed DH can be imposed on immunized mice by i.v. injections of peritoneal exudate cells pulsed with Ag in vitro in the presence of TGF-beta. Thus, the immune regulatory mechanisms that operate to protect the eye from immunogenic inflammation can be invoked in previously sensitized mice. In addition, tolerance could not be generated in presensitized mice by either i.v. injection of soluble Ag or painting of hapten on UVB-exposed skin. It seems that the strategies used by the eye to create a deviant state of immunity in the face of pre-existing conventional immunity may be unique.
Gamma delta T cells can recognize nonclassical MHC in the absence of conventional antigenic peptides.
Authors: Weintraub B C , Jackson M R , Hedrick S M 
Published: December 2022

Abstract
Although T cells expressing the gamma delta Ag receptor (gamma delta cells) have been found in all organisms with lymphoid systems, little is understood about their immunologic function. It is known that T cells that express the alpha beta Ag receptor (alpha beta cells) fight infection by recognizing foreign Ag as peptide presented by MHC molecules; however, it is not known how gamma delta cells recognize Ag. Characterization of ligands of the gamma delta cell Ag receptor (TCR) could lead to a better understanding of gamma delta cell function. We have characterized the ligand of the G8 gamma delta cell; we find that G8 gamma delta cells are stimulated by T22, a nonclassical class I MHC molecule. To study the involvement of peptides in gamma delta cell recognition, T22 was expressed in cells deficient in peptide transporter function and in Drosophila cells, which can express MHC molecules without associated peptides. We find no evidence that G8 gamma delta cells recognize peptides bound to T22. These results suggest that some gamma delta cells, unlike alpha beta cells, may not be restricted to recognition of peptide-MHC complexes.
Identification of residues in monoclonal antibody NC10.8 that bind to the sweetener N-(p-cyanophenyl)-N'-(diphenylmethyl)guanidinoacetic acid by using radioligand binding, absorption and fluorescence spectroscopy, computer-aided molecular modeling, and site-directed mutagenesis.
Authors: Anchin J M , Droupadi P R , DuBois G E , Kellogg M S , Nagarajan S , Carter J S , Linthicum D S 
Published: December 2022

Abstract
The interactive residues for mouse mAb NC10.8, which binds a superpotent guanidinium sweetener N-(p-cyanophenyl)-N'-(diphenylmethyl)guanidinoacetic acid with high affinity (Kd = 5 nM), were examined by using radioligand competitive binding, photoaffinity labeling, absorption and fluorescence spectroscopy, computer-aided molecular modeling, and site-directed mutagenesis. Competitive ligand analogue binding data revealed important structural features and a pH sensitivity for ligand binding. Spectroscopy of the sweetener-mAb complex revealed ligand-induced fluorescence quenching and the presence of a charge-transfer band. Site-directed mutagenesis of L:96W abolished the ligand-induced fluorescence quenching and reduced Ab affinity. The apparent Kd increased from 5 nM to more than 200 nM after such modification. A theoretical model of the Fv region was generated with use of a knowledge-based algorithm, and this model was used to identify the locations of key residues in the complementarity determining regions. These experimental and theoretical studies support the prediction that the sweetener ligand coordinates with the following residues: L:34H contacts the cyanophenyl ring, L:27DR forms a salt bridge with the acetic acid moiety, L:96W forms a pi-pi interaction with the cyanophenyl ring, and H:95E contacts the positively charged aryl nitrogen. These studies are important to our understanding of Ab-ligand specificity and may also shed light on the important chemical motifs responsible for elevated levels of sweetness potency in organic compounds.
Expression of fusion regulatory proteins (FRPs) on human peripheral blood monocytes. Induction of homotypic cell aggregation and formation of multinucleated giant cells by anti-FRP-1 monoclonal antibodies.
Authors: Tabata N , Ito M , Shimokata K , Suga S , Ohgimoto S , Tsurudome M , Kawano M , Matsumura H , Komada H , Nishio M 
Published: December 2022

Abstract
Fusion regulatory proteins (FRPs) are newly defined cell surface molecules that enhance and/or induce virus-mediated cell fusion. Anti-FRP-1 Abs reacted with all of the established cells derived from humans and monkeys, whereas FRPs were found to be selectively expressed on a fraction of monocytes in human PBMCs. Granulocytes expressed no FRP-1 molecules, but approximately 18% of granulocytes expressed FRP-2 molecules. Alveolar macrophages also expressed FRP-1 molecules. FRP-1 expression was enhanced by culture of monocytes, but CD14 expression was not influenced by cultivation. Anti-FRP-1 Abs induced homotypic cell aggregation and multinucleated giant cell formation of monocytes. Anti-beta 2 integrin Ab blocked anti-FRP-1 Ab-induced cell aggregation, and anti-beta 1 integrin Ab and fibronectin inhibited anti-FRP-1 Ab-induced polykaryocyte formation. There was no competitive binding to monocytes between anti-FRP-1 Ab and anti-beta 1 or anti-beta 2 integrin Ab or fibronectin. Furthermore, there was no enhancement of beta 1 and beta 2 integrin expression by anti-FRP-1 Ab on monocytes. These findings suggest that anti-FRP-1 Ab activated integrin systems, and that the functions of anti-FRP-1 Ab were demonstrated through the activated integrin systems. Furthermore, it is inferred that integrin systems are involved in polykaryocyte formation of monocytes.
Regulation of CD14 expression during monocytic differentiation induced with 1 alpha,25-dihydroxyvitamin D3.
Authors: Zhang D E , Hetherington C J , Gonzalez D A , Chen H M , Tenen D G 
Published: December 2022

Abstract
CD14, a monocyte/macrophage receptor for the complex of LPS and LPS binding protein, is a differentiation marker for the monocyte/macrophage lineage. We have analyzed the regulation of CD14 expression during 1 alpha,25-dihydroxyvitamin D3 (VitD3)-induced monocytic differentiation. Using FACS, Northern blotting, and nuclear run-on analyses, we demonstrate that the up-regulation of CD14 expression during monocytic cell maturation is regulated mainly at the level of gene transcription, and that new protein synthesis is required for CD14 induction. We have recently cloned the CD14 5' upstream sequence and demonstrated its tissue-specific promoter activity. Using stable transfection of the monocytoid U937 cell line with a series of deletion mutants of the CD14 5' upstream sequence coupled to a reporter gene construct, we show that bp -128 to -70 is the critical region for the induction of CD14 expression. This region contains two binding sites for the Sp1 transcription factor. A 3-bp mutation at the distal Sp1-binding site not only eliminates Sp1 interaction, but also abolishes most of the VitD3 induction of CD14 expression. Electrophoretic mobility shift analysis does not detect a direct interaction of the CD14 distal Sp1-binding site with the vitamin D3 receptor and its partner, the retinoid X receptor. These data demonstrate that VitD3 induces CD14 indirectly through some intermediary factor, and suggest a critical role for Sp1 in this process.
Induction of NGFI-B gene expression during T cell activation. Role of protein phosphatases.
Authors: Garcia I , Pipaon C , Alemany S , Perez-Castillo A 
Published: December 2022

Abstract
mRNA expression of the immediate-early gene NGFI-B was investigated in T cells during the G0/G1 transition as well as throughout the G1 phase. After stimulation of T lymphocytes with Con A or phorbol 12,13 dibutyrate (PDBu), NGFI-B gene expression showed an induction of at least sevenfold within 3 h of stimulation. Twenty-four h later, however, the level of NGFI-B transcripts had fallen to almost basal levels. Activation of the Ca2+ signaling pathway also produced an induction of this gene, although to a lesser extent than the one obtained after protein kinase C activation. Similar transient kinetics of NGFI-B mRNA were also observed after PDBu stimulation of G1 lymphoblasts. However, the induction of NGFI-B by IL-2 is dependent on the presence of cycloheximide. Con A-induced activation of NGFI-B gene expression was not overcome by cyclosporin A or by 8Br-cAMP, but was partially prevented by dexamethasone. In lymphoblasts, okadaic acid caused the induction of NGFI-B gene expression, indicating a role for the serine/threonine protein phosphatases PP1 and PP2A in the regulation of this gene in resting cells. Okadaic acid-induced NGFI-B transcripts were significantly more stable than PDBu-induced NGFI-B mRNA. Thus, the level of NGFI-B transcripts in T cells might be determined by the balance between the activities of several serine/threonine protein kinases and phosphatases. Together, these findings indicate that the transient induction of NGFI-B transcripts is associated with normal lymphocyte activation. Because the mRNA for NGFI-B codes for a zinc-finger DNA-binding protein, these results suggest that NGFI-B participates in transcriptional regulation during T cell activation.
Characterization of the activation-associated isoform of CD43 on murine T lymphocytes.
Authors: Jones A T , Federsppiel B , Ellies L G , Williams M J , Burgener R , Duronio V , Smith C A , Takei F , Ziltener H J 
Published: December 2022

Abstract
A rat mAb termed 1B11 recognizes a 130-kDa cell surface glycoprotein expressed on T lymphocytes. Transfection studies using the Cd43 gene transfected into murine L cells, and immunoblots using anti-peptide Abs specific for the CD43 polypeptide identified the 1B11 Ag as the 130-kDa isoform of murine CD43. mAb 1B11 fails to recognize the other major CD43 isoform, 115-kDa CD43, either by Western blotting or by FACS analysis, thus differing from the previously characterized anti-CD43 mAb S7 that recognizes only the CD43 115-kDa isoform and not the CD43 130-kDa isoform. CD43 130-kDa recognized by mAb 1B11 is differentially expressed on T lymphocytes. Whereas most CD4-8-, CD4+8+, and CD4-8+ thymocytes express 130-kDa CD43 constitutively, the Ag is expressed by less than 20% of CD4+ T cells in immature and mature populations. On activation, expression of 130-kDa CD43 is up-regulated dramatically on CD4+ T lymphocytes, and to a lesser extent on CD8+ T lymphocytes. In contrast, T cell activation resulted in only minor up-regulation of 115-kDa CD43. CD43 130-kDa contains sialylated O-linked carbohydrate; however, recognition by mAb 1B11 is not dependent on the presence of sialic acid. Interestingly, removal of sialic acid by neuraminidase treatment of 1B11-negative CD4+ T lymphocytes or 1B11-negative EL4 cells confers 1B11 reactivity, suggesting that the 1B11 epitope is masked by sialic acid residues on the CD43 115-kDa isoform. The isoelectric point (pl) of 130-kDa CD43 was determined to be 6.0, which is higher than the pl reported for 115-kDa CD43. Different molecular properties of 115-kDa and 130-kDa CD43 and their differential expression in T cell subsets may indicate specific roles for these CD43 isoforms in T cell ontogeny and/or T cell function.
Thymic development in human CD4 transgenic mice. Positive selection occurs after commitment to the CD8 lineage.
Authors: Paterson R K , Burkly L C , Kurahara D K , Dunlap A , Flavell R A , Finkel T H 
Published: December 2022

Abstract
Developing T cells are positively selected on the basis of their recognition of polymorphic MHCs (major histocompatibility molecules). The CD4 and CD8 co-receptors, together with a compatible TCR-alpha beta, bind class II and class I MHC, respectively, delivering a signal that allows T cell maturation to proceed along the appropriate co-receptor lineage. During development, thymocytes first co-express CD4 and CD8 and subsequently commit to a single co-receptor phenotype. Debate exists over the stage at which positive selection occurs. Positive selection may precede or accompany co-receptor lineage commitment or occur subsequent to the acquisition of a single co-receptor phenotype. We developed transgenic (TG) mice expressing human CD4 (huCD4) on T cells. To study differentiation of CD8+ cells, huCD4 TG mice were bred with mice lacking class I MHC (class I-). This enabled us to assess maturation of mCD8+mCD4+huCD4+ thymocytes to mCD8+mCD4-huCD4+ cells after interaction between huCD4 and mclass II MHC. In the absence of huCD4, class I- mice failed to produce mCD8+ cells. However, expression of huCD4 allowed development of mCD8+mCD4-huCD4+ T cells, suggesting that selection of cells precommitted to the mCD8+mCD4- lineage occurred. Importantly, CD8+ T cells were increased in both the thymus and the periphery of huCD4 TG x class I- animals, indicating their intrathymic origin. V beta 14+ CD8+ T cells were also increased, as predicted for positive selection of CD8+ cells bearing class II-reactive TCRs. These data provide evidence that positive selection occurs at a late stage of thymocyte differentiation, after commitment to the CD8 lineage.
Retroviral transduction of protein kinase C-gamma into tumor-specific T cells allows antigen-independent long-term growth in IL-2 with retention of functional specificity in vitro and ability to mediate tumor therapy in vivo.
Authors: Chen W , Schweins E , Chen X , Finn O J , Cheever M A 
Published: December 2022

Abstract
The aim of our study was to examine the potential usefulness of transducing the protein kinase C-gamma (PKC-gamma) cDNA gene into tumor-specific T cells as a technique for facilitating the generation of large numbers of functional Ag-specific T for tumor therapy. Murine CD8+, F-MuLV gag-specific CTL clones, and CD4+, F-MuLV env-specific Th clones, as well as bulk-cultured T cell lines with defined Ag specificity to FBL-3, a Friend murine leukemia virus (F-MuLV)-induced tumor, were transduced with a retroviral vector pZipNeoPKC-gamma and selected in G418. The results demonstrated that PKC-gamma-transduced clones remained activated in culture, as evidenced by continued expression of up-regulated levels of IL-2R, which were as high after 6 mo in culture without Ag restimulation as 24 h after Ag stimulation. In vitro functional studies demonstrated that PKC-gamma-transduced CD8+ T cell clones maintained specific cytolytic activity to FBL-3, and PKC-gamma-transduced CD4+ T cell clones maintained specific proliferative activity to FBL-3 or F-MuLV Ag presented by irradiated syngeneic APC. Short-term bulk-cultured T cells specific to FBL-3 were also transduced and could be grown long term in vitro with maintenance of functional specificity. In vivo study showed that PKC-gamma-transduced CD4+ T cells were able to proliferate in response to Ag plus IL-2 stimulation in vivo in a similar pattern as the parental T cells. Therapy with adoptively transferred PKC-gamma-transduced T cell clones and lines into syngeneic mice, with or without FBL-3 tumor, showed that the PKC-gamma-transduced T cells were not tumorigenic and were effective in curing mice with disseminated FBL-3.
Endothelial cell-associated platelet-activating factor primes neutrophils for enhanced superoxide production and arachidonic acid release during adhesion to but not transmigration across IL-1 beta-treated endothelial monolayers.
Authors: Hill M E , Bird I N , Daniels R H , Elmore M A , Finnen M J 
Published: December 2022

Abstract
The role of platelet-activating factor (PAF) in stimulating neutrophils during interaction with HUVEC has been investigated using the specific PAF receptor antagonists WEB 2086 and YM 264. PAF antagonists at concentrations up to 40 microM had little effect on the adhesion of neutrophils to control or IL-1 beta-stimulated HUVEC monolayers. However, polarization of neutrophils on adhesion to IL-1-treated HUVEC was markedly diminished in the presence of PAF antagonists. In addition, the PAF antagonists WEB 2086 and YM 264 strongly inhibited the migration of neutrophils across IL-1-treated endothelial monolayers. Priming of neutrophil respiratory burst and arachidonic acid release caused by contact with IL-1-treated endothelial cells was also inhibited by PAF antagonists. However, priming as a consequence of transmigration was not inhibited by either WEB 2086 or YM 264. These results suggest that HUVEC-associated PAF plays a central role in the polarization and subsequent transmigration of neutrophils during interaction with HUVEC monolayers. Moreover, the results further suggest that PAF is responsible for priming neutrophils during contact with HUVECs. However, after transmigration, factors other than PAF are responsible for the priming of neutrophil function.