bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunogenic and antigenic properties of an HIV-1 gp120-derived multiple chain peptide.
Authors: Kelker H C , Schlesinger D , Valentine F T 
Published: December 2022

Abstract
An HIV-1 envelope protein gp120-derived monomeric peptide (amino acid residues 419-439) and its homologous multiple chain peptide (MCP) construct were compared for immunogenicity in mice. The Abs stimulated by the MCP recognized epitopes on the MCP that were not present on the homologous monomer. The anti-419-439 MCP sera recognized a conformational determinant on the native envelope glycoprotein, as indicated by: 1) detection of native but not denatured recombinant envelope glycoprotein by ELISA and dot blot and 2) reaction with infected cell lines expressing gp120 on their surface as detected by flow cytometry. In contrast, the anti-monomer sera were highly specific for the monomer and recognized the envelope glycoprotein at lower titers. The low reactivity of the anti-monomer sera with the envelope glycoprotein was not decreased by denaturation. Reciprocally, murine antiserum to HIV-1 envelope glycoprotein gp160 recognized the MCP construct but not the homologous monomeric peptide. The data indicate that the MCP construct forms additional antigenic determinants not present on the homologous monomer, and that the anti-419-439 MCP Abs recognize a conformational determinant on the envelope glycoprotein not recognized by Abs against the homologous monomer. Furthermore, antisera against another envelope-derived MCP (amino acid residues 105-117) also recognize conformational determinants on the envelope glycoprotein, whereas antisera against the homologous monomeric peptide do not.
BUB/BnJ (H-2q) is a TCR deletion mutant mouse strain (TCR V beta a, KJ16-) that is susceptible to type II collagen-induced arthritis.
Authors: Ortman R A , Holderbaum D , Qu X M , Banerjee S , Haqqi T M 
Published: December 2022

Abstract
Type II collagen-induced arthritis (CIA) in mice is an animal model of autoimmune inflammatory arthritis. Arthritis is induced in susceptible strains of mice (H-2q and H-2r) after immunization with heterologous or autologous type II collagen in CFA. Induction of CIA is T cell dependent and a restricted usage of TCR V beta genes has been found in the arthritic joints and lymph nodes of mice with CIA. However, genes within the MHC are not the only determinants of susceptibility to CIA as SWR/j, AU/ssJ (both H-2q) and RIIIS/J(H-2r) mice are resistant to the induction of CIA. These strains of mice are TCR V beta chain genes deletion mutants (TCR V beta a and TCR V beta c haplotypes) and it was hypothesized that these mice are resistant to CIA because of the absence of a particular set of V beta TCR genes that are genomically deleted in these strains of mice. We now show that BUB/BnJ mice (H-2q) are T cell subsets deficient because of the genomic deletion of TCR V beta 5, 8, 9, 11, 12, and 13 sub-families. Our data demonstrate that despite the deficiency in T cell subsets from genomic deletion of TCR V beta genes, BUB mice are highly susceptible to the development of CIA. These results indicate that genomic deletion of certain TCR V beta genes alone is not in itself sufficient to confer resistance to CIA. These results further suggest that other unknown gene(s) must also contribute to the induction of CIA.
Phenotypic and functional cellular differences between human CD3- decidual and peripheral blood leukocytes.
Authors: Deniz G , Christmas S E , Brew R , Johnson P M 
Published: December 2022

Abstract
CD3- leukocyte clones derived from human decidualized endometrial tissue of first trimester pregnancy have been compared with CD3- PBL clones. Most CD3- decidual granulated leukocyte (DGL) clones were CD16- CD56+, whereas most CD3- PBL clones were CD16+ CD56+. CD3- DGL and PBL clones, whether CD16+ or not, showed MHC-nonrestricted NK cell activity. However, CD3- CD16- DGL clones had low cytotoxic activity against the NK-resistant cell line BSM, whereas CD3- CD16+ DGL and CD3- PBL clones were strongly cytotoxic. Cytolytic activity has also been investigated in respect of target cell HLA-G expression, because this nonpolymorphic class I MHC molecule is expressed selectively by invasive fetal cytotrophoblast. Class I HLA Ag loss cell mutants were killed efficiently by CD3- DGL clones. Expression of transfected HLA-B8 increased their sensitivity to lysis by most CD3- DGL clones, whereas expression of transfected HLA-G commonly led to decreased target cell killing. In addition, the effects of uncloned CD3- DGL on the one-way MLR have been examined. These cells were very poor responders and, unless cultured to induce expression of class II MHC molecules, were also very poor stimulators. When fresh CD3- DGLs were added as third-party cells, either autologous or allogeneic to responder cells, [3H]TdR incorporation was decreased in the MLR. Thus, CD3- DGL clones express MHC-nonrestricted cytolytic activity, notably against HLA-negative cells, but expression of HLA-G offers protection to target cells. In addition, CD3- DGL may function to suppress allogeneic responses.
Activation of a novel serine/threonine kinase that phosphorylates c-Fos upon stimulation of T and B lymphocytes via antigen and cytokine receptors.
Authors: Nel A E , Taylor L K , Kumar G P , Gupta S , Wang S C , Williams K , Liao O , Swanson K , Landreth G E 
Published: December 2022

Abstract
Ligation of Ag receptors in T and B lymphocytes initiates signal transduction cascades which alter the expression of genes that regulate cellular proliferation and differentiation. The transmission of signals from the membrane to the nucleus is mediated principally through the action of protein tyrosine and serine/threonine kinases. We have identified and characterized a novel serine/threonine kinase that phosphorylated the proto-oncogene product, c-Fos, and is termed Fos kinase. Fos kinase was rapidly activated after ligation of the CD3 and CD2 receptors in Jurkat and normal human T lymphocytes and in response to IL-6 and anti-IgM in the human B cell lines AF10 and Ramos, respectively. The phorbol ester, PMA, was also a potent inducer of Fos kinase activity in all of the above populations, suggesting that PKC plays a role in the regulation of this enzyme. Fos kinase phosphorylates c-Fos at a site near the C-terminus, as well as a peptide derived from this region (residues 359-370, RKGSSSNEPSSD), and Fos peptide competitively inhibited c-Fos phosphorylation. Fos kinase was shown to be distinct from other identified serine/threonine kinases, including protein kinase A, protein kinase C, casein kinase II, MAP kinases, p70S6K and p90RSK. Fos kinase was purified by anion exchange chromatography and exhibited an apparent M(r) = 65,000 and isoelectric point = 6.1. Fos kinase may play a role in transcriptional regulation through its capacity to phosphorylate c-Fos at a site required for expression of the transcriptional transrepressive activity of this molecule. Moreover, its rapid activation suggests it may have a wider role within signal transduction cascades in lymphocytes.
Efficient induction of immunoglobulin production in neonatal naive B cells by memory CD4+ T cell subset expressing homing receptor L-selectin.
Authors: Tsuji T , Nibu R , Iwai K , Kanegane H , Yachie A , Seki H , Miyawaki T , Taniguchi N 
Published: December 2022

Abstract
The humoral response in newborns is mainly restricted to IgM production, which may be attributable to the naive nature of both B and T cells at birth. In light of the current evidence that memory (CD45RO+) CD4+ T cells help B cell differentiation, the present study was undertaken to examine whether a specified population within memory CD4+ T cells could induce the maturation of neonatal naive B cells. In the conventional PWM-stimulated cultures, the generation of IgG- and IgA-producing cells in addition to IgM production by neonatal B cells was significantly enhanced by co-cultures with memory, but not naive, CD4+ T cells. Memory CD4+ T cells were further divided into two populations based on expression of homing receptor L-selectin. These memory CD4+ T cell subpopulations appeared to behave in different fashions concerning help for Ig production by naive (sIgD+) and mature (sIgD-) B cells. L-selectin-negative memory CD4+ T cells exhibited helper function for Ig secretion by mature B cells. Intriguingly, Ig production by neonatal B cells as well as adult naive B cells, although less than that by mature B cells, was efficiently promoted by L-selectin-positive memory CD4+ T cells rather than L-selectin-negative ones. The results suggest that the capability of neonatal naive B cells to secrete IgG and IgA can be elicited by appropriate T-cell signals, especially from the L-selectin-positive population within memory CD4+ T cells, seemingly indicating its possible role for isotype switching in B cells.
Simultaneous regulation of CD2 adhesion and signaling functions by a novel CD2 monoclonal antibody.
Authors: van Kemenade F J , Tellegen E , Maurice M M , Lankester A C , Kuijpers T W , Brouwer M , de Jong R , Miedema F , van Lier R A 
Published: December 2022

Abstract
Accessory molecules on T cells can support adhesion and transduce agonistic signals that facilitate Ag receptor-induced T cell activation. The T cell differentiation Ag CD2 may exert both functions, as has been amply demonstrated in studies with CD2 mAbs. In addition, experiments in which either purified ligand (CD58) or transfected CD2 and CD58 molecules were used have confirmed this notion. However, controversy exists as to whether CD2 alters its affinity for CD58 in the course of T cell stimulation, and whether this putative affinity change affects CD2-mediated activation signals. We now describe a CD2 mAb (HIK27) that recognizes an epitope constitutively expressed on resting T cells and induces increased adhesiveness of CD2 toward CD58. Addition of HIK27 to a stimulatory but nonmitogenic pair of CD2 mAbs induces a strong proliferative response. Finally, HIK27 was found to be co-mitogenic with CD58 expressed on sheep erythrocytes, B cell lines, and CD58-transfected L cells. The simultaneous modulation of CD2 adhesion and signaling on HIK27 binding suggests that both functions of the molecule may be enhanced in the course of T cell stimulation.
A disease-related epitope of Torpedo acetylcholine receptor. Residues involved in I-Ab binding, self-nonself discrimination, and TCR antagonism.
Authors: Wall K A , Hu J Y , Currier P , Southwood S , Sette A , Infante A J 
Published: December 2022

Abstract
Residues 146-162 of the Torpedo californica acetylcholine receptor alpha-subunit contain the immunodominant T cell epitope for experimental autoimmune myasthenia gravis-susceptible C57BL/6 mice. To develop potential therapeutic peptides, a detailed analysis of the epitope was undertaken. Truncated and substituted synthetic peptides were tested as stimulators of T cell clones and immune lymph node cells. Critical residues spanned positions 151-159. Y151 and V156 were critical for MHC binding. The results indicated a general motif for binding to I-Ab to be an aromatic or hydrophobic residue (preferentially Y or F) at position i followed by an uncharged residue at position (i + 5). Lysine was not tolerated at position (i + 8). Residues D152, K155, S157, and I158 were important T cell contact residues. A peptide corresponding to the murine 146-162 sequence, which differs from the Torpedo sequence at 5 residues, bound to I-Ab but was nonimmunogenic, consistent with the assigned TCR and I-Ab contact residues. These results suggest that tolerance is responsible for the lack of T cell cross-reactivity with the murine acetylcholine receptor. Substituted peptides were tested for the inhibition of T cell clone responses and for TCR antagonism. Although peptides substituted at residues 157 and 158 inhibited most clones, no single peptide could completely inhibit all clones or primed lymph node cells. These findings indicate that antagonist peptides may be useful in inhibiting T cell responses to complex Ag displaying a single immunodominant epitope. Multiple antagonists used in combination may be required for maximum inhibition of the response.
The leukocyte integrin p150,95 (CD11c/CD18) as a receptor for iC3b. Activation by a heterologous beta subunit and localization of a ligand recognition site to the I domain.
Authors: Bilsland C A , Diamond M S , Springer T A 
Published: December 2022

Abstract
p150,95 is a member of the leukocyte integrin family of adhesion proteins. Compared with LFA-1 and Mac-1, p150,95 is less well functionally characterized. Although p150,95 has complement receptor activity for iC3b and has been designated complement receptor type 4, transfected cells expressing p150,95 do not bind iC3b-sensitized cells. We report that cells cotransfected with a human p150,95 alpha subunit and a chicken, but not human, beta subunit bind IgM-iC3b-coated erythrocytes, suggesting that interactions between the alpha and beta subunits can regulate p150,95 adhesiveness. Furthermore, purified human p150,95 binds to cell-bound iC3b-coated erythrocytes. Because binding to iC3b by cellular and purified p150,95 is specifically abolished by mAbs that localize to the I domain of p150,95, we suggest that the I domain of the p150,95 alpha subunit is an important ligand recognition site for iC3b.
Eosinophil transendothelial migration induced by cytokines. II. Potentiation of eosinophil transendothelial migration by eosinophil-active cytokines.
Authors: Ebisawa M , Liu M C , Yamada T , Kato M , Lichtenstein L M , Bochner B S , Schleimer R P 
Published: December 2022

Abstract
Activation of HUVEC monolayers by IL-1 beta or TNF-alpha induces migration of eosinophils across the endothelial monolayer (i.e., transendothelial migration) in vitro. In the present study, we demonstrate that culture of freshly isolated eosinophils in the presence of IL-5 for 24 to 48 h before use in the assay dramatically potentiated CD18-dependent eosinophil transendothelial migration through unstimulated endothelial monolayers. Granulocyte macrophage (GM)-CSF induced eosinophil transendothelial migration but did not induce neutrophil transendothelial migration. When IL-1 beta-activated endothelial cells were used, GM-CSF, IL-3, or IL-5 caused only modest potentiation of eosinophil transendothelial migration. Since activated endothelial cells are known to produce GM-CSF, we hypothesized that endothelial-derived GM-CSF might play a role in the process of IL-1 beta-induced eosinophil transendothelial migration. IL-1 beta-activated endothelial monolayers grown on the permeable supports produced 0.3 +/- 0.1 ng/ml of GM-CSF during a 4-h incubation and neutralizing Ab against GM-CSF inhibited eosinophil transendothelial migration by 48%, suggesting that endothelial-derived GM-CSF may participate in the response. Eosinophils purified from bronchoalveolar lavage 18 to 20 h after experimental Ag challenge in the lungs of allergic volunteers showed enhanced transendothelial migration, indicating that the cells may have undergone cytokine activation in vivo. Eosinophil-active cytokines may contribute to the preferential accumulation of eosinophils in vivo in part via potentiation of eosinophil transendothelial migration.
Action and target cell specificity of human macrophage-stimulating protein (MSP).
Authors: Skeel A , Leonard E J 
Published: December 2022

Abstract
Macrophage-stimulating protein (MSP) induces mouse resident peritoneal macrophages to become responsive to the chemoattractant C5a and to ingest C3bi-coated erythrocytes. We now show that MSP action is not limited to complement-induced responses, because it also induced responsiveness to the noncomplement chemoattractant casein. In addition to stimulating responsiveness to attractants, MSP functioned alone as a chemoattractant for resident peritoneal macrophages, with an optimal concentration of approximately 0.2 nM. A critical difference between MSP and C5a is that resident macrophages did not migrate to C5a without an additional stimulus such as MSP in the cell suspension, whereas macrophages suspended in medium alone migrated to MSP in the attractant well. Thus, in contrast to C5a, MSP seems capable of a dual role, both activator and attractant. MSP had no effect on responsiveness of mouse peritoneal exudate macrophages to C5a; nor could it attract exudate macrophages or human blood monocytes. Absorption studies showed that resident macrophages have a receptor for MSP, but exudate macrophages do not. In view of these findings, it seems that the biological role of MSP is not as a recruiter of blood monocytes to sites of inflammation, but as an activator of mature macrophages. The MSP-induced activated state for responsiveness to C5a or C3bi was transient, and decayed at a first order rate with a t 1/2 of approximately 1 h. This is a new example of the transience of activation induced in macrophages by proinflammatory stimuli.
Physical association of complement receptor type 3 and urokinase-type plasminogen activator receptor in neutrophil membranes.
Authors: Xue W , Kindzelskii A L , Todd R F , Petty H R 
Published: December 2022

Abstract
A previous study has shown that Fc gamma RIIIB (CD16), an extensively glycosylated glycosyl-phosphatidylinositol-linked neutrophil membrane protein, specifically co-caps with the iC3b R (CR3; CD11b/CD18). This study tests the possible physical interactions of another extensively glycosylated glycosyl-phosphatidylinositol-linked protein, the urokinase-type plasminogen activator receptor (uPAR), with CR3. Receptors were labeled using fluorochrome-conjugated F(ab')2 fragments of an anti-CR3 mAb. In some cases cells were capped using second step F(ab')2 fragments of an anti-mouse F(ab')2 antiserum. After 30 min at 37 degrees C, 65 +/- 4% of the cells exhibited CR3 caps whereas 61 +/- 2% demonstrated uPAR caps. When CR3-capped cells were probed with F(ab')2 fragments of anti-uPAR conjugated to a distinct fluorochrome, 45 +/- 3% of the cells co-capped uPAR. When uPAR was capped, 48 +/- 2% of the cells co-capped CR3. Similar levels of co-capping were observed using a DNP-conjugated anti-CR3 F(ab')2 and an anti-DNP second step F(ab')2 reagent for capping or using FITC-uPA as a probing reagent. Furthermore, CR3-uPAR co-capping and/or co-clustering was also observed using anti-CR3 IgM and Mn2+ as integrin aggregation stimuli. Significant co-capping of anti-CD14, anti-CD59, anti-Mo5, anti-HLA, or NBD-PE (a lipid probe) was not observed. Moreover, CR3 and uPAR co-capping was blocked by N-acetyl-D-glucosamine, but not by six other saccharides, suggesting that a lectin-like site may participate in co-capping. This suggests that CR3 may regulate adhesive events by several mechanisms, including the regulation of the spatial distribution of uPAR.
Serum IgA-mediated neutralization of HIV type 1.
Authors: Burnett P R , VanCott T C , Polonis V R , Redfield R R , Birx D L 
Published: December 2022

Abstract
The sera of 33 HIV-1-infected individuals, previously shown to neutralize HIV-1MN in vitro, were screened by ELISA for IgA reactivity against rgp120MN and a synthetic V3MN loop peptide. Six were selected for evaluation of the effect of serum IgA from infected individuals on the in vitro infection of susceptible target cells by HIV-1MN. By using protein G immobilized on Sepharose, we depleted the sera of IgG to a level undetectable by nephelometry and viral envelope-specific ELISA. The IgA component of the IgG-depleted serum was affinity purified with immobilized jacalin, a lectin that selectively binds the IgA1 fraction of human Ig. IgG-depleted sera and purified IgA1 serum fractions showing IgA reactivity against rgp120MN and V3MN by ELISA inhibited the in vitro infection of CEM-ss cells by HIV-1MN, but sera depleted of both IgG and IgA1 did not. These data show that, like serum IgG, serum IgA from selected HIV-1-infected individuals is capable of neutralizing HIV-1MN in vitro. The biologic significance of this observation and the identities of serum IgA-recognized HIV-1 neutralization epitopes remain to be determined.
Target organ-specific up-regulation of the MRC OX-40 marker and selective production of Th1 lymphokine mRNA by encephalitogenic T helper cells isolated from the spinal cord of rats with experimental autoimmune encephalomyelitis.
Authors: Weinberg A D , Wallin J J , Jones R E , Sullivan T J , Bourdette D N , Vandenbark A A , Offner H 
Published: December 2022

Abstract
Lewis x Buffalo F1 rat lymphocytes express both forms of the allelic marker RT7.1 (Lewis) and RT7.2 (Buffalo). We generated myelin basic protein (MBP)-specific encephalitogenic F1 T helper cell lines and adoptively transferred them into naive irradiated Lewis recipients, which enabled us to detect and isolate donor T cells (with RT7.2) within the recipients. The spinal cord and cerebrospinal fluid (CSF) were highly enriched for the donor T cells compared with the blood and spleen. The donor cell number peaked on the first day of disease in the spinal cord and CSF and decreased as the disease progressed. A high percentage of the donor T cells isolated from the spinal cord were positive for the T helper cell activation marker OX-40, whereas a (lower) percentage of CSF donor cells expressed OX-40. Donor cells isolated from blood or spleen were negative for OX-40 expression. In contrast, the IL-2 receptor (CD25) was positive on all the transferred T cells in all tissue sites examined. Cell-sorting experiments showed that the MBP-specific donor cells were enriched for IFN-gamma, IL-2, TNF-alpha, and IL-3 mRNA when compared with the host-recruited spinal cord cells, whereas similar amounts of IL-10 mRNA were produced by both populations. Lymphokine mRNA production was also enriched in donor T cells isolated from the spinal cord compared with donor T cells isolated from the spleen. The spinal cord donor cells produced higher levels of IL-2, IFN-gamma, and IL-3 mRNA, whereas similar amounts of IL-10 and TNF-alpha mRNA were produced from donor cells isolated from the spleen and the spinal cord. Our data suggest that the amount/percentage, activation state, and enhanced lymphokine production at the site of inflammation are all important factors in determining the autoimmune potential of Ag-specific effector T helper cells.
Hyaluronate is costimulatory for human T cell effector functions and binds to CD44 on activated T cells.
Authors: Galandrini R , Galluzzo E , Albi N , Grossi C E , Velardi A 
Published: December 2022

Abstract
Lymphohematopoiesis, cell matrix adhesion, homing of leukocytes, T cell activation, and tumor metastasis are mediated through the CD44 family of cell surface receptors. We have recently shown that anti-CD44 mAb trigger protein tyrosine kinase-dependent activation of T cell effector functions. Here, we show that hyaluronate (HA), a CD44 ligand, in conjunction with CD3/TCR-mediated stimuli, is costimulatory for human peripheral blood T cell proliferation, for IL-2 production by Th clones, and for release of trypsin-like esterase by cytolytic T cell clones. A human T cell line, HUT-78, was found to bind HA and on HA coating it was used as a target for cytolytic T cell clones. After anti-CD3 stimulation, CD3+/CD8+ clones acquire the ability of lysing HA-coated HUT-78 cells more efficiently than the same HA-uncoated targets. Resting peripheral blood T cells and T cell clones do not adhere to HA-coated plates. However, 24-h anti-CD3 mAb stimulation gives them the transient ability to bind HA. HA adhesion of activated T cells and T cell clones, as well as that of T cell lines, is blocked by one anti-CD44 mAb (J-173). Two other anti-CD44 mAbs induce a 10-fold increase in HA adhesiveness of anti-CD3-stimulated peripheral blood T cells. This impressive HA adhesiveness is also readily blocked by J-173 anti-CD44 mAb. These data indicate that 1) HA is costimulatory for human T cell effector functions in conjunction with CD3/TCR-mediated stimuli, 2) the capacity to bind HA is acquired by resting T cells and T cell clones after anti-CD3 stimulation, and 3) HA binding occurs via specific interaction with CD44 molecules expressed on activated T cells.