bluuebunny/crossref_metadata_2025_split huggingface dataset:
B cell lines as models for inherited phagocytic diseases: abnormal superoxide generation in chronic granulomatous disease and giant granules in Chediak-Higashi syndrome.
Authors: Volkman D J , Buescher E S , Gallin J I , Fauci A S 
Published: January 2023

Abstract
Epstein Barr virus (EBV)-transformed B cell lines (BCL) were developed from peripheral blood lymphocytes of individuals with Chediak-Higashi syndrome (CHS) and chronic granulomatous disease (CGD), and were compared to EBV BCL from normals. The cells that were studied expressed both B cell surface antigens and EBV nuclear antigens. BCL from normals contained small cytoplasmic granules. When stimulated with phorbol myristate acetate (PMA), these B cells reduced nitroblue tetrazolium (NBT) and generated significant amounts of superoxide. However, two other phagocytic stimuli, A23187 and f-methionine-leucine-phenylalanine, failed to stimulate BCL oxygen metabolism. BCL from seven individuals with CGD failed to either reduce NBT or generate superoxide on PMA stimulation, although the lines were morphologically similar to BCL from normals. In contrast, CHS-BCL generated superoxide more rapidly than did normals, and contained the characteristic giant granules of CHS. Thus, continuous BCL evidencing the phenotypic abnormalities of inherited human phagocytic diseases can provide large numbers of cells for biochemical and genetic study.
Oligosaccharide structure of human C4.
Authors: Chan A C , Atkinson J P 
Published: January 2023

Abstract
The oligosaccharide structure of human C4 was studied by using C4 purified from plasma and C4 secreted by human hepatoma-derived cell line, HepG2. The alpha- and beta-chains of human C4 are glycosylated, whereas the gamma-chain is devoid of carbohydrate. The alpha-chain has three complex fucosylated oligosaccharides of the biantennary type, one each on the alpha 2, alpha 3, and alpha 4 fragments. The beta-chain has a single high mannose oligosaccharide primarily of the Man9GlcNAc2 type. The approximately 2000 Mr difference between the alpha-chains of the two C4 gene products (C4A and C4B) was localized to the alpha 2 fragment and is not due to carbohydrate. Sulfation of the C4 alpha-chain was localized to the alpha 4 fragment of the alpha-chain. Hence, the Mr difference between the two gene products is likely to reside in amino acid differences. The oligosaccharide structure of three incompletely processed C4 molecules was also analyzed. These molecules have the oligosaccharide composition of the appropriate individual subunits. Therefore, intracellular proteolytic processing to the multi-chain form of C4 is not required for proper oligosaccharide processing.
Human endothelial cells modulate granulocyte adherence and chemotaxis.
Authors: Zimmerman G A , Wiseman G A , Hill H R 
Published: January 2023

Abstract
Although human endothelial cells (EC) and granulocytes interact in several ways, the factors that regulate such interactions are not well defined. In this study we found that EC and their products directly altered granulocyte adherence (GA) and chemotactic activity. The spontaneous adherence of granulocytes to human umbilical vein EC monolayers was significantly reduced at 5, 15 and 30 min if the granulocytes were preincubated with EC that were stimulated by rocking. At 30 min the spontaneous adherence of EC-preincubated granulocytes was 36% of that of control granulocytes (P = 0.004). The augmented adherence stimulated by FMLP was also decreased (54% of control) by preincubation of the granulocytes with rocked EC. The ability of stimulated EC to inhibit GA was attenuated when the EC monolayers that were used for preincubation with the granulocytes were pretreated with the cyclooxygenase inhibitor indomethacin. GA to unstimulated EC was not significantly altered by indomethacin or aspirin, suggesting that cyclooxygenase products do not influence GA under resting conditions. Preincubation of granulocytes with rocked EC monolayers or supernatant media from rocked EC monolayers diminished their chemotactic response to FMLP by 45 to 65. This inhibition was also attenuated by pretreatment of the EC with indomethacin. EC supernatant medium caused a rapid increase in granulocyte intracellular cyclic AMP, with a maximum increase to 200% of control at 1 min. These data indicate that stimulated EC release one or more arachidonic acid products that alter spontaneous and inflammatory mediator-stimulated granulocyte activity. Prostacyclin, a major cyclooxygenase product of EC arachidonate, depressed inflammatory mediator-augmented GA to EC monolayers and chemotaxis when present in nanomolar concentrations. We conclude that EC-derived prostacyclin, alone or in combination with other EC products, alters GA and chemotaxis stimulated by inflammatory mediators. This provides a mechanism by which EC may modulate granulocyte distribution as well as granulocyte responses that are influenced by adherence, such as the release of toxic oxygen metabolites and granular enzymes.
Murine TH response to influenza virus: recognition of hemagglutinin, neuraminidase, matrix, and nucleoproteins.
Authors: Hurwitz J L , Hackett C J , McAndrew E C , Gerhard W 
Published: January 2023

Abstract
BALB/c mice were primed with type A influenza virus by footpad injection or by aerosol infection with PR8 [A/PR/8/34-(H1N1)]. Isolated T cells from draining lymph nodes were then tested for their proliferation in the presence of purified viral proteins hemagglutinin, neuraminidase, matrix, and nucleoprotein. Significant responses [( 3H]thymidine incorporation) were seen against each of the four proteins after either priming scheme. When helper T (TH) cell clones were isolated by hybridoma formation from two different strains of mice, responsiveness (interleukin 2 production) towards each protein was against apparent. Of 12 virus-specific T cell hybridomas isolated, four responded to matrix, three to nucleoprotein, one to neuraminidase, three to hemagglutinin, and one cell was of undefined specificity. Each hybridoma was also tested for recognition of the HK virus [A/Hong Kong/1/68-(H3N2)], which differs in subtype from the priming strain. All matrix-specific cells, two nucleoprotein-specific cells, and the cell of undefined specificity were cross-reactive with HK virus. H1-subtype specificity was seen for all hemagglutinin and neuraminidase-specific cells and one of the three nucleoprotein-specific cells. Because many virus-immune TH cells recognize antigenically variable determinants, a significant fraction of TH cell function may be lost after virus evolution. When selecting priming schemes for long-term immunization against influenza, the isolated enhancement of TH cells recognizing conserved determinants on matrix and nucleoprotein may therefore be considered.
Interleukin 2 activates a receptor-associated protein kinase.
Authors: Benedict S H , Mills G B , Gelfand E W 
Published: January 2023

Abstract
The interleukin 2 (IL 2) receptor complex has been shown to consist of at least two IL 2 binding molecules, one of 55 to 57 kd (gp57Tac) and one of 75 to 78 kd apparent m.w. The data presented here indicate that a protein of m.w. 78,000 (pp78) co-immunoprecipitates with gp57Tac when a monoclonal antibody against gp57Tac is used. The 78 kd molecule is phosphorylated in vitro within the immune complex only in the presence of exogenously added IL 2, whereas the 57 kd molecule is phosphorylated equally in the presence or absence of IL 2. Phosphorylation in vitro of pp78 was demonstrated in extracts of human peripheral blood T cells (PBL-T) and the human T cell line Jurkat, but not in extracts of the human macrophage line U937 or the murine T cell line 2.8.2. Metabolic phosphorylation in intact cells reflects results observed in vitro; both pp78 and gp57Tac are phosphorylated in PBL-T and Jurkat, but not in U937. These data demonstrate that the IL 2 receptor complex contains an IL 2 responsive protein kinase activity and may signal the cell through a phosphorylation event.
The IRG-47 gene is IFN-gamma induced in B cells and encodes a protein with GTP-binding motifs.
Authors: Gilly M , Wall R 
Published: January 2023

Abstract
The murine pre-B cell line 70Z/3 has been studied extensively as a model system for B cell differentiation induced by cytokines and mitogens. IFN-gamma treatment of 70Z/3 pre-B cells activates Ig kappa L chain gene expression, resulting in the appearance of surface IgM characteristic of B cells. We have isolated and characterized a new cDNA clone, called IRG-47, whose mRNA is transiently elevated up to 30-fold at 4 to 6 h after IFN-gamma induction of 70Z/3 pre-B cells. The IFN-gamma induction of IRG-47 mRNA occurs in all pre-B and in most B lineage cell lines examined but is only induced in three cell lines tested from other lineages. Activation of IRG-47 gene transcription appears to account for the rapid increase in IRG-47 mRNA after induction. Transcription of the IRG-47 gene is down-regulated 10 h postinduction at a time when the level of IRG-47 mRNA is also declining. The complete sequence of the IRG-47 cDNA clone is predicted to encode a 47-KDa protein which, although unique in its sequence, bears resemblance to a number of nucleotide-binding proteins. The IRG-47 coding sequence contains all three highly conserved peptide motifs in the appropriate spacing characteristic of guanine nucleotide-binding proteins.
Tolerance induction in T helper (Th1) cells by thymic macrophages.
Authors: Jayaraman S , Luo Y , Dorf M E 
Published: January 2023

Abstract
Most macrophages in the peripheral tissues present Ag optimally to a variety of functionally distinct Th cells. Although thymic macrophages have been implicated in deleting autoreactive thymocytes, their role in influencing the functional capacities of mature T cells is not clear. We have established a normal untransformed macrophage cell line, named TMC, from the mouse thymus. The TMC line presents protein Ag to an IL-4-producing Th2 type Th clone after IFN-gamma treatment as evidence by T cell proliferation and the release of IL-3 and IL-4. However, these thymic macrophages are inefficient at stimulating a well characterized cytochrome C-specific IL-2-producing Th1 clone, A.E7. Ag presentation by TMC results in the production of IL-3 but not IL-2 production or proliferation of A.E7 cells. This selective Ag presentation defect to Th1 cells is corrected by the addition of live but not fixed allogeneic irradiated spleen cells, suggesting that the thymic macrophages lack the expression of costimulatory activity required for Th1 activation. This is further demonstrated by the failure of live thymic macrophages to provide costimulatory activity to A.E7 cells stimulated with fixed spleen cells plus the antigenic peptide 81-104. Exposure of A.E7 cells to paraformaldehyde-treated TMC in the presence of 81-104 peptide induces specific hyporesponsiveness, anergy. These data demonstrate that thymic macrophages can have a profound influence on the response of selected T cells to Ag. Furthermore, the nature of the T cell stimulus is also critical because Th1 and Th2 cells responded equally well to the T cell mitogen, Con A, and a bacterial superantigen presented by the thymic macrophages.
Mutations in the third, but not the first or second, hypervariable regions of DR(beta 1*0101) eliminate DR1-restricted recognition of a pertussis toxin peptide.
Authors: Olson R R , De Magistris M T , Di Tommaso A , Karr R W 
Published: January 2023

Abstract
We have examined the role of 12 polymorphic residues of the beta-chain of the HLA-DR1 class II molecule in T cell recognition of an epitope of pertussis toxin. Murine L cell transfectants expressing wild-type or mutant DR1 molecules (containing single amino acid substitutions in DR(beta 1*0101)) were used as APC in proliferation assays involving nine DR1-restricted T cell clones specific for peptide 30-42 of pertussis toxin. Four different patterns of recognition of the mutants were found among the pertussis-specific clones. Residues in the third hypervariable region (HVR) of DR(beta 1*0101) are critically important for all the T cell clones; amino acid substitutions at positions 70 and 74 abrogated recognition by all of the T cell clones, and substitutions at positions 67 and 71 eliminated recognition by most of the clones. In contrast, most single amino acid substitutions in the first and second HVR, predicted to be located in the floor of the peptide binding groove, had little or no effect on the proliferative responses of these clones. However, the involvement of beta-chain first and second HVR residues was demonstrated by the inability of transfectants expressing wild-type DR(beta 1*0404) (DR4Dw14) or DR(beta 1*1402) (DR6Dw16) to present peptide to these clones. These beta-chains have completely different first and second HVR compared with DR(alpha,beta 1*0101) although the third HVR are identical. These results illustrate the functional importance of third HVR residues of DR(beta 1*0101) and allow definition of the molecular interactions of the DR1 molecule with the 30-42 peptide.
Use of human universally antigenic tetanus toxin T cell epitopes as carriers for human vaccination.
Authors: Valmori D , Pessi A , Bianchi E , Corradin G 
Published: January 2023

Abstract
Synthetic constructs were assembled as multiple Ag peptide systems containing repetitive sequences of Plasmodium falciparum and Plasmodium berghei, the causative agents of human and murine malaria respectively, and two universal human tetanus toxin T cell epitopes 830-843 and 947-967. These constructs were tested for antibody production in mice and for their capacity to stimulate human PBL and tetanus toxin-specific T cell clones. A high antibody titer can be obtained in mice when multiple Ag peptide systems are injected in various adjuvants or in PBS alone. Furthermore, all constructs can activate PBL from every donor tested. However, a variable response was obtained when different clones specific for the two tetanus toxin universal epitopes were used. These constructs may represent possible candidates for a malaria vaccine.
T cell-induced allotypic suppression. Origin of the CD8+ T cells maintaining IgG2ab suppression.
Authors: Majlessi L , Benaroch P , Bordenave G 
Published: January 2023

Abstract
One of the problems raised by the T cell-induced allotypic suppression is the origin (donor or host) of the T cells responsible for the chronicity of the suppression. To address this point, we used T cells from Igha/a Thy-1.2 mice whose natural T cell activity against IgG2ab was enhanced in vivo. These T cells were injected into newborn Ighb/b Thy-1.1 mice where they induced complete suppression of IgG2ab expression in around 70% of these recipients. During a study that lasted more than 1 yr, we found that about 3% of the recipient splenocytes were T cells of the donor type. By means of suppression-transfer experiments, using either Thy-1.2+ or Thy-1.1+ cell-depleted splenocytes from mice suppressed in this manner we were able to unambiguously show that Thy-1.2+ cell-depleted splenocytes were incapable of transferring the suppression, whereas Thy-1.1+ cell-depleted splenocytes could. We thus demonstrated that suppression was maintained throughout the recipient's life by donor Thy-1.2+ T cells.
The beta 2-microglobulin dissociation rate is an accurate measure of the stability of MHC class I heterotrimers and depends on which peptide is bound.
Authors: Parker K C , DiBrino M , Hull L , Coligan J E 
Published: January 2023

Abstract
Stable, recombinant, water-soluble complexes of HLA-A2 and HLA-B27 were reconstituted from 125I-labeled beta 2-microglobulin (beta 2m), a synthetic peptide, and HLA H chain fragments expressed as inclusion bodies in the Escherichia coli cytoplasm. Using this system, we were able to show: 1) the t1/2 of beta 2m dissociation from HLA complexes at 37 degrees C varied from approximately 40 h to less than 1 h, depending on the peptide employed for reconstitution. Peptide length and composition were found to be critical factors in determining the beta 2m dissociation rate. Endogenous peptides form complexes that are about as stable as those formed with typical antigenic peptides. 2) Peptide exchange reactions, in which an exogenous peptide replaces the peptide that is already bound by the class I molecule, proceed readily for complexes that have rapid beta 2m dissociation rates. Thus, difficulties in demonstrating peptide binding to complexes that contain endogenous peptides can be attributed to the stability of the endogenous peptide/class I molecule complex. 3) The peptide exchange reaction does not require concomitant beta 2m dissociation. 4) Distal parts of the class I molecule, which are not directly involved in peptide binding or beta 2m binding, have a major impact on the stability of class I molecules. Thus, these studies show that the dissociation rate of beta 2m is an excellent measure of how tightly a given peptide binds to class I MHC molecules, that the ability to bind peptide is tightly coupled to the binding of beta 2m and vice versa, and that regions of the molecule distal from the binding site influence the stability of peptide binding.
Peptide binding to soluble HLA-DR4 molecules produced by insect cells.
Authors: Scheirle A , Takacs B , Kremer L , Marin F , Sinigaglia F 
Published: January 2023

Abstract
HLA-DR4Dw4 molecules were expressed in insect Sf9 cells. The transmembrane and cytoplasmic domains of the DR4 alpha- and beta-chains were replaced by the carboxy terminal sequence of decay accelerating factor, leading to a phosphatidyl inositol glycan membrane anchor. This structure contains a cleavage site for phosphatidyl inositol-specific phospholipase C, allowing efficient solubilization of the rDR4 molecules. We present evidence that infected insect cells express properly associated surface heterodimers and are able to present antigenic peptides to DR4Dw4-restricted T cell clones. Phosphatidyl inositol-specific phospholipase-cleaved recombinant molecules exhibited in vitro binding characteristics similar to DR4 molecules purified from lymphoblastoid cells. In terms of peptide specificity, pH optimum, kinetics, and affinity they were indistinguishable within the limits of our assay system. However, the peptide binding capacity of the recombinant molecules was higher than that of native DR4 molecules.
Analysis of HIV-induced autoantibodies to cryptic epitopes on human CD4.
Authors: Callahan L N , Roderiquez G , Mallinson M , Norcross M A 
Published: January 2023

Abstract
Antilymphocyte antibodies, including autoantibodies to CD4, have been reported in AIDS patients and are postulated to contribute to T cell depletion and immunologic dysfunction. In this paper, we characterize and localize binding sites of human anti-CD4 autoantibodies from a number of HIV+ patients. Epitope mapping by ELISA and Western blotting, together with cross-competition experiments, showed that common autoepitopes were localized to at least two topographically separate sites on the fourth domain of sCD4. These sites were partially dependent on the carboxyl terminus of the soluble molecule and were not exposed on full length membrane CD4, even under denaturing Western blotting conditions. Peptide screening identified peptides from the fourth and third domains that were recognized by several, but not all, anti-CD4 serum samples. Soluble CD4 affinity-purified antibodies were predominantly IgG1 and were not induced to bind mCD4 after gp120 binding to T cells. Analysis of HIV seroconversion panels showed that the appearance of anti-CD4 antibodies followed HIV seroconversion by 6 to 12 months and paralleled anti-gp120 reactivity. This suggested a correlation between immune reactivity to envelope and anti-CD4 antibody production. Together, the data indicate that human anti-CD4 antibodies recognize cryptic conformational and linear epitopes on a cleaved form of CD4. These findings suggest that HIV may induce abnormal cleavage of full length CD4, thereby exposing immunogenic self epitopes normally hidden from humoral and cellular immune interactions. This model of abnormal processing of self Ag has general implications for autoantigen exposure in other autoimmune disorders.
The Use of Trypan Blue to Demonstrate the Immediate Skin Reaction in Rabbits and Guinea Pigs
Authors: Ramsdell Susan Griffith 
Published: January 2023

Summary and Conclusions
By the intravenous administration of trypan blue, the immediate skin reaction to a homologous antigen may be demonstrated in serum treated rabbits and guinea pigs in the usual testing for direct, passive and reversed passive sensitization in both animals.
The same type of reaction may be shown to an injection of sera of sensitized animals, of sera showing so-called primary toxicity for the guinea pig, and to very high dilutions of histamine.
It is believed that the infiltration of the dye into these reaction sites is, at present, to be looked upon as no more than a sort of indicator of the presence of an edematous change which is an expression of a toxic action upon the capillary endothelium.
Ultra Microscopic Findings in the Serum of the Anaphylactic Guinea Pig
Authors: Ramsdell Susan Griffith , Kast Clara C. 
Published: January 2023

Summary
Using the ultra-microscope in a study of the serum of the sensitized guinea pig, we have found the flocculation phenomenon, as postulated by Kopaczewski, to occur irregularly, to appear to be simply a very weak precipitin reaction, and to have no constant relation to the capacity of the animal to show shock.
Certain changes in the appearance of the sera were often noted following shock, but the nature of these were not resolvable by the use of the technic as outlined.
Influence of membrane Ig receptor density and affinity on B cell signaling by antigen. Implications for affinity maturation.
Authors: George J , Penner S J , Weber J , Berry J , Claflin J L 
Published: January 2023

Abstract
We have initiated a series of experiments to explore the effect of changes in density of the surface Ig receptor (mIg) on Ag:mIg interactions. We transfected into the surface Ig-negative B cell line M12.4 H and L chain constructs known to effect a 10-fold change in antibody binding affinity for the naturally occurring hapten phosphocholine (PC). Two sets of stable transfectants were generated and those expressing levels of mIg comparable to the range normally seen on splenic B cells were studied. One set expressed an unmutated VH and an unmutated VL. The second set expressed the same pair of V regions except for a single somatic change in CDR3 of VH; this substitution increases the affinity of antibody for PC from 3 x 10(4) M-1 to 3 x 10(5) M-1. Ag:mIg interactions were assessed in the transfected cell lines by measuring calcium mobilization induced by stimulation with soluble PC Ag. As expected, the mutation that increased affinity for PC increased the sensitivity of transfectants to PC Ag. Relatively small changes in receptor number had a dramatic effect in the quantity and quality of a calcium response. Significantly, we found that Ag-specific signaling could occur with only a few thousand receptors per cell. Signaling differences were most noticeable with PC protein Ag (T-dependent form) compared with PC polysaccharide Ag (T-independent form). These results suggest that the down-regulation of mIg that follows B cell activation may have evolved to assist in the selection of B cell clones with higher affinity for Ag. Furthermore, the results also provide an explanation for why selection of higher affinity clones can occur with protein Ag but only poorly so with polymeric Ag.