bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure-function study of the p55 subunit of murine IL-2 receptor by epitope mapping.
Authors: Lorenzo F , Jaulin C , Vita N , Froussard P , Ferrara P , Jankovic D L , Theze J 
Published: December 2022

Abstract
Using a cell-free translation system we have expressed the Mr 55,000 subunit of the murine IL-2R (p55 IL-2R), which binds IL-2 with low affinity (Kd = 10 nM). Mutants and truncated forms of p55 IL-2R have been used to map the epitopes recognized by three anti-p55 IL-2R mAb: 135D5, 7D4, and 2E4. The mAb 135D5 inhibits IL-2 binding to p55 IL-2R and recognizes an epitope located between amino acids 64 to 125. This epitope can be mimicked by a synthetic peptide corresponding to the region defined by residues 72 to 88. However, the mAb 7D4 and 2E4 do not affect the IL-2 binding to p55 IL-2R. These mAb recognize an epitope of p55 IL-2R lying between residues 125 to 212 that can be mimicked with a peptide corresponding to amino acids 188 to 208. A strong correlation emerged between the experimental results on epitope mapping and predictions of potential antigenicity of murine p55 IL-2R. In addition, we described two internal initiation sites of p55 IL-2R mRNA under the in vitro conditions used leading to the production of significant amounts of N-terminal truncated p55 IL-2R proteins.
Effect of 1,25-dihydroxyvitamin D3, lipopolysaccharide, or lipoteichoic acid on the expression of NADPH oxidase components in cultured human monocytes.
Authors: Levy R , Malech H L 
Published: December 2022

Abstract
Human blood monocytes in culture gradually lose their capability to produce superoxide when stimulated. Addition of 10(-8) M 1,25-dihydroxyvitamin D3 [1, 25(OH)2D3], 2.5 ng/ml LPS, or 25 ng/ml lipotechoic acid (LTA) prevented this decrease in monocyte respiratory burst when added at initiation of culture. Monocytes cultured for 4 days in the presence of 1,25 (OH)2D3, LPS, or LTA retained the ability to produce superoxide and 1,25 (OH)2D3 actually increased the oxidative capacity compared with fresh monocytes. Furthermore, addition of 1,25(OH)2D3, LPS, or LTA to monocytes at day 4 of culture restored the oxidase activity by day 7 to the levels seen with fresh monocytes. Cytosol or membrane fractions from monocytes cultured with or without the agents indicated above were tested in a cell-free assay of superoxide production by mixing with fresh monocyte membrane or cytosol fractions, respectively. Membrane oxidase activity from these cultured monocytes showed only minimal changes regardless of the agent present or absent from the culture. However, the activity of cytosol fractions from these same cultured monocytes showed substantial differences depending upon the culture conditions and these changes correlated closely with changes in activity of the intact monocytes from which the cytosols were derived. Immunoblot analysis of monocyte membranes and cytosol was used to assess the amount of the 91-kDa and 22-kDa subunits of membrane oxidase cytochrome 558 (gp91 and p22), and the 47-kDa and 67-kDa cytosol oxidase factors (p47 and p67) in the different culture conditions. The gp91 and p22 decreased during culture of monocytes, although the decrease was only apparent by 7 days in culture. When 1,25 (OH)2D3, LPS, or LTA were present at the initiation of culture, then an increase in gp91 and p22 was seen as compared with fresh monocytes at day 4. When these agents were added at day 4 of culture, the levels of gp91 and p22 at day 7 were similar to fresh monocytes. The p67 cytosol oxidase component showed little change in amount by immunoblot regardless of the time in culture or whether 1,25(OH)2D3, LPS, or LTA were present. In contrast, the p47 cytosol oxidase factor decreased by day 4 of culture and was markedly depressed by day 7. Monocytes cultured in the presence of either 1,25(OH)2D3, LPS, or LTA preserved the expression of p47, whereas addition of these agents to monocytes at day 4 of culture restored the expression of p47 by day 7 to the level of fresh monocytes.(ABSTRACT TRUNCATED AT 400 WORDS)
Functional properties of guinea pig eosinophil leukotriene B4 receptor.
Authors: Ng C F , Sun F F , Taylor B M , Wolin M S , Wong P Y 
Published: December 2022

Abstract
It is currently thought that pulmonary eosinophils play a proinflammatory role in bronchial asthma. Leukotriene B4 (LTB4) is being considered as an important mediator in regulating eosinophil function because of its potent activities in inducing leukocyte chemotaxis, chemokinesis, degranulation, and aggregation. Because the LTB4 receptor has not been characterized in eosinophils, we report in this study the presence of a functional high affinity receptor for LTB4 on guinea pig (GP) eosinophils. Scatchard analysis of saturation binding studies yielded a Kd of 1.4 +/- 0.2 nM (mean +/- SEM, n = 3) and a Bmax of 1.6 +/- 0.4 pmol/mg of protein for LTB4 in GP eosinophil membranes. A linear Scatchard plot was obtained, suggesting that GP eosinophil membranes expressed only a single high affinity LTB4 receptor population. Saturation binding studies in whole cells also yielded a linear Scatchard plot, with a Kd of 2.8 +/- 0.96 nM (mean +/- SEM, n = 4) and a Bmax of 4 x 10(4) +/- 6 x 10(3) receptors/cell. Competitive binding studies using several compounds with structures similar to that of LTB4 showed that these agents bound to the receptor in the following descending order of affinity (Ki, nM): LTB4 (0.96) less than TB3 (1.0) greater than 20-hydroxy-LTB4 (3.5) greater than 12(R)-hydroxy-5,8,14-cis,10-trans-eicosatetraenoic acid (20) greater than 12(S)-hydroxy-5,8,14-cis,10-trans-eicosatetraenoic acid (231) greater than 20-carboxy-LTB4 (350) greater than 5(S),12(S)-dihydroxy-6,10-trans,8,14-cis-eicosatetraenoic acid (541). This rank order of potency in binding affinity correlates closely with the ability of these compounds to induce both chemotaxis and superoxide anion generation. Analysis of the structure-activity relationship suggests that the 12R-hydroxyl group and a cis double bond at the C-6 position are important for optimal agonist binding to the LTB4 receptor present in GP eosinophil membranes. The results suggest that LTB4 may be an important chemoattractant for eosinophils in GP and may induce the release of reactive oxygen species from this cell.
Phorbol ester-mediated inhibition of IFN-alpha/beta gene transcription in blood mononuclear leukocytes.
Authors: Sandberg K , Eloranta M L , Gobl A E , Alm G V 
Published: December 2022

Abstract
The phorbol ester PMA efficiently inhibits the in vitro IFN-alpha and -beta responses in human blood monocytes induced by Sendai virus and in natural IFN-producing cells induced by glutaraldehyde-fixed herpes simplex virus-infected human amnion (WISH) cells. This PMA-mediated inhibition of IFN-alpha/beta secretion is correlated with considerably reduced levels of IFN-alpha/beta mRNA, as determined by Northern blot analysis. Nuclear run-on assays further show that, at least in monocytes, PMA inhibits transcription of the IFN-alpha and -beta genes. The synthetic diacylglycerol 1-oleoyl-2-acetylglycerol has the same effects as PMA, and the protein kinase inhibitor staurosporine prevents the PMA-mediated inhibition of IFN-alpha/beta expression. These results suggest a role for protein kinase C in the inhibition of IFN-alpha/beta responses. The PMA does not inhibit the accumulation of IFN-beta mRNA in monocytes stimulated by Sendai virus in the presence of cycloheximide, indicating that the inhibitory action of the phorbol ester requires de novo protein synthesis.
Mutational analysis of the cross-reactive idiotype of the A strain mouse.
Authors: Hasemann C A , Capra J D 
Published: December 2022

Abstract
The elucidation of the structural basis for expression of the cross-reactive Id of the A strain mouse (CRIA) in response to the hapten p-azophenylarsonate has been the object of considerable research effort. Most conclusions regarding the amino acids involved in Id expression have been inferential, based on comparisons of amino acid sequences, chain recombination experiments, or chemical modification of particular amino acids. To more rigorously designate the amino acids critical to the phenotype of the CRIA, a system for the expression and directed mutation of antibody molecules was developed. Based on the baculovirus expression of foreign proteins in cultured insect cells, functional antibodies can be produced at very high levels in vitro. By the process of oligonucleotide-directed mutagenesis, a series of specific amino acid changes were introduced into both the H and L chains of a prototype CRIA expressing antibody molecule. Analysis of the gain or loss of polyclonal Id and each of several monoclonal idiotopes has allowed us to identify more precisely the amino acids responsible for expression of the CRIA. Thus we have shown that expression of the CRIA is equally dependent on amino acids in the second and third CDR of the H chain. Furthermore, the idiotopes studied surround the Ag-binding site and clearly involve multiple interactions in several of the L and H chain CDR.
The T cell receptor V alpha 11 gene family. Analysis of allelic sequence polymorphism and demonstration of J alpha region-dependent recognition by allele-specific antibodies.
Authors: Jameson S C , Nakajima P B , Brooks J L , Heath W , Kanagawa O , Gascoigne N R 
Published: December 2022

Abstract
Allelic polymorphism in TCR loci may play an important role in shaping the T cell repertoire and in disease susceptibility. We have used a combination of antibody and sequence analysis to investigate polymorphism in the murine V alpha 11 family. Two different antibodies have been analyzed that recognize particular V alpha 11 family members of the V alpha b and V alpha d haplotypes. One antibody shows J alpha dependency, suggesting a conformational element to the epitope. Investigation of the anti-V alpha 11 staining pattern on different mouse strains indicates that there is a marked influence of MHC haplotype on V alpha 11 selection and that V alpha 11 is preferentially expressed on CD4+ cells. Sequence analysis of V alpha 11 genes from the V alpha a, V alpha b, and V alpha d haplotypes shows two potential regions for the haplotype-specific epitopes. The relatedness of the different V alpha 11 family members from different haplotypes suggests that the V alpha 11.1/11.2 gene duplication is relatively recent, but that V alpha 11.3 separated much earlier. Differences between V alpha 11.3 and V alpha 11.1/11.2 are concentrated in the putative complementarity determining regions (CDR), whereas differences between alleles are not clearly clustered. However, the V alpha 11.1a and V alpha 11.1d alleles differ from V alpha 11.1b and V alpha 11.2b in CDR1. A V alpha 11.2-expressing anti-cytochrome c T cell has the same V-J junction as a V alpha 11.1-bearing cell with a similar fine specificity, indicating that V alpha 11.1b and V alpha 11.2b do not contribute different Ag specificities.
Cloning of the cDNA for the serine protease homolog CAP37/azurocidin, a microbicidal and chemotactic protein from human granulocytes.
Authors: Morgan J G , Sukiennicki T , Pereira H A , Spitznagel J K , Guerra M E , Larrick J W 
Published: December 2022

Abstract
Human cationic antimicrobial protein (CAP37) is a neutrophil granule protein with monocyte chemotactic and antibacterial activity. A CAP37 cDNA clone of 899 bp was isolated from an HL-60 cDNA library using degenerate oligonucleotide probes based on partial N-terminal sequence of the CAP37 protein. The cDNA sequence predicts an open reading frame of 753 bp encoding a protein of 251 amino acids. A 26-residue eukaryotic signal peptide and a potential 7 amino acid pro-peptide are present at the N-terminus of the protein. The cDNA sequence also predicts three N-linked glycosylation attachment sites and eight intramolecular cysteines. The deduced amino acid sequence of CAP37 shows 44, 42, and 32% homology at the amino acid level to neutrophil elastase, myeloblastin, and cathepsin G, respectively, suggesting that CAP37 is a member of the serine protease gene family. CAP37 does not possess serine protease activity probably due to mutations in two of three residues in the catalytic triad of the "charge relay system." Whereas CAP37 is expressed in undifferentiated HL-60 cells no message is detected in mature neutrophils.
Tumor rejection antigens on BALB3T3 cells transformed by activated oncogenes.
Authors: Torigoe T , Sato N , Takashima T , Cho J M , Tsuboi N , Qi W M , Hara I , Wada Y , Takahashi N , Kikuchi K 
Published: December 2022

Abstract
The clonal expression of tumor rejection Ag (TRA) was analyzed on nine different clones derived from parental BALB3T3 cells that were transfected with activated H-ras, polyoma middle T (PyMT), c-myc, and v-src oncogenes. It was shown that Bras-h clone, which is an activated H-ras oncogene-induced transformant, expressed TRA as assessed in the transplantation study using syngeneic BALB/c mice. This TRA was not detected on parental BALB3T3 nontransformed cells, suggesting that TRA could be expressed in the BALB3T3 cell transformation. Furthermore, the cross-protection experiments indicated that this TRA was also conferred on other BALB3T3 transformants with high anchorage-independent growth potential such as an activated H-ras transformant Bras-d, and PyMT transformants BMT-f, BnMT-11, BnMT-20, except in the case of one H-ras transformant Bnr-12. In contrast, this TRA was not expressed on the transfectants with little or no anchorage independent growth potential such as a PyMT transfectant BnMT-4, a c-myc transfectant Bmyc-7, and a v-src transfectant Bsrc-7. We developed the mAb BRH19 that could react with TRA+ clones but not with TRA- clones. This mAb makes an immunoprecipitate, which is composed of a 50-kDa single polypeptide chain from Bras-h cell lysate. An injection to mice with this antigen could confer the protection against Bras-h challenge. These data indicate that the 50-kDa putative TRA molecule could be expressed in close association with the cell transformation, irrespective of the introduced oncogenes, and there may exist some regulatory mechanisms rather than individually distinct manners for the expression of TRA.
A comparative study of the neutrophil stimulatory activity in vitro and pro-inflammatory properties in vivo of 72 amino acid and 77 amino acid IL-8.
Authors: Nourshargh S , Perkins J A , Showell H J , Matsushima K , Williams T J , Collins P D 
Published: December 2022

Abstract
IL-8, a potent neutrophil-activating protein, can be produced by many cell types including monocytes, lymphocytes, fibroblasts, neutrophils, and endothelial cells. Depending on the cell source, the N-terminal amino acid sequence of IL-8 displays heterogeneity that has been shown to confer differences in its neutrophil stimulatory activity in vitro. Despite these observations the relative potency of different IL-8 molecules in vivo is unknown. To address this question we have investigated the biologic activity of the two predominant forms of IL-8, the 72 and the 77 amino acid proteins, in vitro and in vivo. In vitro, human rIL-8(72) and human rIL-8(77) dose dependently induced adherence of rabbit peritoneal neutrophils and human neutrophils to laminin-coated plates and elevated cytoplasmic levels of Ca2+ ([Ca2+]i) in fura-2 loaded neutrophils. In these in vitro assays human rIL-8(72) was more potent than human rIL-8(77) while inducing comparable responses to human rC5a. With respect to enhancing [Ca2+]i, neutrophils desensitized to human rIL-8(72) failed to respond to human rIL-8(77). However, neutrophils fully desensitized to human rIL-8(77) could exhibit a partial response to human rIL-8(72). Further, human rIL-8(72) was approximately 10-fold more effective than human rIL-8(77) in displacing human [125I]rIL-8(72) from rabbit peritoneal neutrophils in a receptor-binding assay. In vivo, intradermally administered human rIL-8(72) and human rIL-8(77) induced 111In-neutrophil accumulation and edema formation in rabbit skin. In contrast to the in vitro studies, the two forms of IL-8 gave identical responses in vivo although they were less potent than human rC5a. Our results demonstrate that, in vitro, human rIL-8(72) is more potent than human rIL-8(77) in stimulating neutrophils. It may be that IL-8)72) has a greater affinity and/or efficacy for the neutrophil IL-8 cell-surface receptors. One possibility for the observation that both forms of IL-8 are equipotent in inducing inflammatory responses in vivo is that the extended form is proteolytically cleaved to the more biologically active IL-8(72).
Isolation and characterization of a protein from hagfish serum that is homologous to the third component of the mammalian complement system.
Authors: Fujii T , Nakamura T , Sekizawa A , Tomonaga S 
Published: December 2022

Abstract
The 192-kDa protein HX, a major component of serum that specifically binds to zymosan particles, was prepared from the plasma of the hagfish (Eptatretus burgeri) by ion-exchange chromatography and gel filtration. HX, present at a concentration of 0.8 mg/ml in the original plasma, was composed of two distinct subunits of 115 kDa and 77 kDa, respectively, which were linked by disulfide bonds. The protein had the same electrophoretic mobility as beta-globulin. Digestion by trypsin resulted in a specific cleavage of the 115-kDa subunit and a change in its immunoelectrophoretic mobility in the anodal direction, leaving the 77-kDa subunit intact. Treatment with SDS and urea resulted in the splitting of the 115-kDa subunits into 68-kDa and 45-kDa components, but this splitting was inhibited by pretreatment with methylamine, suggesting the presence of a thiol ester bond in the 115-kDa subunit. The amino acid composition of HX revealed a striking resemblance to that of human C3. We conclude, therefore, that the 192-kDa protein isolated in this study is analogous to C3, which plays a key role in the mammalian C system.
Autoantibody to the alternative pathway C3/C5 convertase and its anti-idiotypic response. A study in affinity.
Authors: Spitzer R E , Stitzel A E , Tsokos G C 
Published: December 2022

Abstract
In an effort to understand the development and control of autoantibody production, we studied the affinity of autoantibody to the alternative pathway C3/C5 convertase (C3 nephritic factor (C3NeF)) and its autoanti-idiotypic antibodies, Ab2 alpha and Ab2 beta. These were isolated and purified from newborns, normal adults, and patients with membranoproliferative glomerulonephritis. In all cases, both IgG and IgM C3NeF were available for study. The affinity of IgG and IgM C3NeF for their natural Ag (10(8) liters/mol) as well as for the internal image of that Ag displayed on Ab2 beta was high (10(10) liters/mol). Furthermore, the affinity of IgG C3NeF was nearly 100-fold higher in patients than in newborns, whereas there were no significant changes with IgM C3NeF. By contrast, there were not differences in the affinity of IgG Ab2 alpha (which does not display any likeness to the native Ag) from normal adults and patients to any C3NeF isolate. There was, however, a progressive increase in affinity between both Ab2 alpha preparations and IgG C3NeF from newborns, adult normal subjects, and patients, implying an alteration in C3NeF to account for the changes in affinity. These data suggest that Ag-driven affinity maturation occurs with autoantibody but may not occur within the idiotypic network. These data also indicate that as autoantibody affinity matures, it appears to modify its idiotype, perhaps in an effort towards autoregulation.
Stimulation of human T lymphocytes by Leishmania lipophosphoglycan-associated proteins.
Authors: Russo D M , Turco S J , Burns J M , Reed S G 
Published: December 2022

Abstract
Lipophosphoglycan (LPG) is a glycoconjugate present on the surface of Leishmania promastigotes that has been reported to promote intracellular survival of these parasites, to protect mice against leishmaniasis, and to elicit T cell responses in infected mice and humans. We investigated whether LPG and its components could elicit proliferative responses and cytokine secretion from leishmaniasis patient PBMC. LPG prepared by standard methods (LPG-1) stimulated patients T cells to proliferate and secrete IFN-gamma. LPG was fractionated into several components. An LPG-1-specific T cell line was shown to respond to the core region but not to the repeating saccharide units. LPG-1 was fractionated to yield an LPG-free- associated protein complex and an LPG-2 fraction that was more than 95% depleted of associated protein. The ability of LPG-2 to stimulate T cells was significantly decreased over that of LPG-1. In contrast, LPG-AP stimulated T cell proliferation and IFN-gamma production. Therefore, proteins associated with LPG were effective in eliciting patient T cell responses, whereas the glycolipid enriched moiety was weakly effective or ineffective at stimulating these responses.
Mice can recover from pulmonary influenza virus infection in the absence of class I-restricted cytotoxic T cells.
Authors: Scherle P A , Palladino G , Gerhard W 
Published: December 2022

Abstract
Intranasal exposure of athymic (nu/nu) BALB/c mice to influenza virus leads to a persistent infection of the respiratory tract from which the mice die, usually within 3 to 4 wk with symptoms of general cachexia. However, if these nude mice were injected 1 day after infection, with approximately 10(6) cells from individual virus-specific MHC class II-restricted Th cell clones, they showed greatly reduced mortality and the titers of infectious virus in their lungs were reduced, often to undetectable levels. By coinfecting mice with pairs of antigenically distinct viruses and subsequently determining the extent of clearance of each type of virus, it could be shown first that the clearance mechanism was immunologically specific but did not display the typical crossreaction of class I-restricted cytotoxic T (Tc) cells. In addition, neither primary nor memory Tc responses could be detected in these mice. Second, Th cell clones promoted clearance solely of those viruses that contained the specific Th cell determinant, i.e., Th cell-nonreactive bystander viruses were not cleared. These findings were compatible with virus clearance being effected either directly after recognition of infected class II-positive cells by the transferred Th cells or indirectly via promotion of a glycoprotein-specific antibody response. The latter seems to be the case because transfer of Th cells into infected T and B cell-deficient SCID mice did not result in virus clearance, although transfer of an anti-hemagglutinin antibody cocktail did. Thus, a virus-specific Tc cell response is not a requirement for recovery from a pulmonary influenza virus infection.