bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular mapping of a pathogenically relevant BP180 epitope associated with experimentally induced murine bullous pemphigoid.
Authors: Liu Z , Diaz L A , Swartz S J , Troy J L , Fairley J A , Giudice G J 
Published: December 2022

Abstract
Bullous pemphigoid (BP) and herpes gestationis (HG) are subepidermal blistering diseases associated with an autoimmune response directed against BP180, an epidermal hemidesmosomal glycoprotein. The pathogenic relevance of this Ag/Ab system was established by the recent demonstration that IgG Abs reactive with the murine form of BP180 (mBP180) are capable of triggering a subepidermal blistering disease after passive transfer into neonatal BALB/c mice. The aim of the present study was to determine the fine specificity of the pathogenically relevant Abs in this experimental model of BP. Four high titer rabbit-anti-mBP180 antisera were included in this analysis--only two of which exhibited pathogenic activity in the passive transfer model. Immunoblot analysis using a panel of mBP180 deletion mutants revealed that each of the four rabbit sera reacted with at least three distinct sites on the mBP180 ectodomain; however, this technique failed to distinguish between the reactivity patterns of the pathogenic and nonpathogenic sera. An alternative technique, liquid phase immunoadsorption analysis, was used to identify one mBP180 antigenic site, comprising 9 to 12 amino acids and designated mBP1, that was specifically recognized by the two pathogenic sera. Pre-adsorption of pathogenically active IgG preparations with fusion proteins containing the mBP1 antigenic site resulted in complete blocking of immunofluorescence reactivity with the murine basement membrane zone (BMZ) and in complete neutralization of pathogenic activity. Anti-BMZ reactivity displayed by nonpathogenic Abs was not altered or diminished by pre-adsorption with this same mBP180 recombinant protein. These findings should help to elucidate the immunopathologic mechanisms responsible for human BP and HG and may have significant implications in the diagnosis and treatment of these autoimmune diseases.
Activated adhesion of CTL to MHC class I but not to fibronectin is inhibited by cis unsaturated fatty acids and phenylarsine oxide.
Authors: Anel A , Mescher M F , Kleinfeld A M 
Published: December 2022

Abstract
Binding of CTL to MHC class I or fibronectin is activated through TCR signaling. Once activated, CTL adhesion to MHC class I results in tyrosine phosphorylation of CTL substrates, phosphatidylinositol (PI) turnover, and degranulation. Although activated adhesion to fibronectin does not itself initiate PI hydrolysis or degranulation, these responses are amplified once they become activated. In the present study we have examined the effect of cis unsaturated fatty acids (FA) and phenylarsine oxide (PAO) on CD8-mediated adhesion of CTL to immobilized class I protein and on biochemical and functional events that are triggered by this adhesion. Previous studies have shown that FA and low concentrations of PAO inhibit specific tyrosine phosphorylation events and degranulation but have no effect on PI turnover or CTL-target cell conjugates. The present results show that pretreating CTL with cis unsaturated, but not saturated, FA and low concentrations of PAO (&lt; 0.5 microM) inhibit soluble anti-TCR-triggered binding of CD8 to immobilized MHC class I, tyrosine phosphorylation of CTL substrates, PI turnover, and degranulation. Addition of cis unsaturated FA or PAO after CTL have been allowed to bind to immobilized class I protein did not affect the level of adhesion. In contrast, neither cis unsaturated FA nor PAO affected the TCR-activated binding of CTL to fibronectin. These results suggest that activation of adhesion to the class I and fibronectin ligands involves divergent different pathways that can be distinguished by the FA and PAO agents.
Selection for S107-V11 gene expression by peritoneal B cells in adult mice.
Authors: Pennell C A 
Published: December 2022

Abstract
Peritoneal B-1 cells in adult mice express a restricted repertoire of V genes. To determine the basis for the nonrandom expression of one VH gene (the V11 gene in the S107 family), and to determine if this gene is nonrandomly expressed early in development, we amplified rearranged S107 genes in adult and neonatal tissues taken from B10.H-2aH-4bp/Wts (2a4b) mice. In adult peritoneal B cells, the S107-V11 gene was found to be productively rearranged up to five times more frequently than V1, another member of the S107 VH gene family. This did not occur in adult spleen, or in neonatal spleen or liver. In these three tissues the productive S107-V11/V1 rearrangement ratios ranged from 0.5 to 0.9. This difference suggests that S107-V11-expressing peritoneal B cells in adult mice have been selected and clonally expanded. Clonal expansion is further suggested by the differing ratios of productive to nonproductive rearrangements. In adult peritoneal B cells, the S107-V11 productive/non-productive ratio is higher than that of V1, consistent with the clonal expansion of S107-V11-expressing cells but not of V1-expressing cells. Analysis of the VHDJH junctional sequences in the productive S107-V11 rearrangements reveals that there are no predominant restrictions in the lengths or sequences of the third complementarity determining regions (CDR3). Selection is therefore independent of CDR3 and so must be based on germline-encoded portions of the S107-V11 region.
Identification of recombinant filarial proteins capable of inducing polyclonal and antigen-specific IgE and IgG4 antibodies.
Authors: Garraud O , Nkenfou C , Bradley J E , Perler F B , Nutman T B 
Published: December 2022

Abstract
Filarial infection is characterized by an immune response associated with the production of Ag-specific IgG4 and IgE and IL-4 and IL-5. To identify filarial Ags capable of inducing such responses and to analyze the role Ags themselves play in sustaining it, 24 recombinant filarial parasite proteins were screened for their ability to be recognized by sera from 67 individuals with tissue-invasive filarial infections. Among the recombinant proteins that were recognized by IgG4 or IgE Abs in 25% of the sera or more, two were selected on the basis of their ability to elicit polyclonal and Ag-specific IgE/IgG4 Abs in vitro. Ov27 (analogous to Ov7/cystatin, a cysteine protease inhibitor) and OvD5B (analogous to Ov33, an aspartyl protease inhibitor) induced both a polyclonal and Ag-specific IgE/IgG4 response that was blocked by neutralizing Abs to IL-4 and to IL-13 or by soluble IL-4 receptors. Recombinant human IFN-gamma and IL-12 also led to a decrease in the production of polyclonal and Ag-specific IgE/IgG4 Abs. In addition, these two recombinant proteins preferentially stimulated the secretion of IL-4, IL-5, and IL-10 (in contrast to IFN-gamma). The data suggest that certain epitopes on filarial Ags preferentially elicit a Th2-type response and provide an in vitro model for dissecting the mechanisms underlying this preferential response.
Characterization of the gene encoding the polymorphic immunodominant molecule, a neutralizing antigen of Theileria parva.
Authors: Toye P G , Metzelaar M J , Wijngaard P L , Nene V , Iams K , Roose J , Nyanjui J K , Gobright E , Musoke A J , Clevers H C 
Published: December 2022

Abstract
Theileria parva, a tick-transmitted protozoan parasite related to Plasmodium spp., causes the disease East Coast fever, an acute and usually fatal lymphoproliferative disorder of cattle in Africa. Previous studies using sera from cattle that have survived infection identified a polymorphic immunodominant molecule (PIM) that is expressed by both the infective sporozoite stage of the parasite and the intracellular schizont. Here we show that mAb specific for the PIM Ag can inhibit sporozoite invasion of lymphocytes in vitro. A cDNA clone encoding the PIM Ag of the T. parva (Muguga) stock was obtained by using these mAb in a novel eukaryotic expression cloning system that allows isolation of cDNA encoding cytoplasmic or surface Ags. To establish the molecular basis of the polymorphism of PIM, the cDNA of the PIM Ag from a buffalo-derived T. parva stock was isolated and its sequence was compared with that of the cattle-derived Muguga PIM. The two cDNAs showed considerable identity in both the 5' and 3' regions, but there was substantial sequence divergence in the central regions. Several types of repeated sequences were identified in the variant regions. In the Muguga form of the molecule, there were five tandem repeats of the tetrapeptide, QPEP, that were shown, by transfection of a deleted version of the PIM gene, not to react with several anti-PIM mAbs. By isolating and sequencing the genomic version of the gene, we identified two small introns in the 3' region of the gene. Finally, we showed that polyclonal rat Abs against recombinant PIM neutralize sporozoite infectivity in vitro, suggesting that the PIM Ag should be evaluated for its capacity to immunize cattle against East Coast Fever.
The serine/threonine phosphatase inhibitor, calyculin A, inhibits and dissociates macrophage responses to lipopolysaccharide.
Authors: Barber S A , Perera P Y , McNally R , Vogel S N 
Published: December 2022

Abstract
LPS-stimulated macrophages (M phi) produce inflammatory mediators that are largely responsible for the pathophysiology associated with septic shock. M phi respond to LPS with rapid protein phosphorylation and dephosphorylation on serine, threonine, and tyrosine residues. If these events are critical for the cellular response to LPS, the kinases and/or phosphatases involved may be vulnerable targets for pharmacologic intervention. Recent studies demonstrated that tyrosine kinase inhibitors block LPS-induced tyrosine phosphorylation of MAP kinases as well as TNF-alpha and IL-1 beta production. To investigate a role for serine/threonine phosphatases, we evaluated the effect of calyculin A, a potent serine/threonine phosphatase inhibitor, on LPS stimulation of murine M phi. Pretreatment of M phi with calyculin A inhibited LPS-induced expression of six immediate-early genes: TNF-alpha, IL-1 beta, IFN-beta, IP-10, IRF-1, and TNFR-2. Calyculin A added 1.5 h after LPS treatment greatly reduced accumulation of IP-10, IRF-1, and TNFR-2 mRNA, but not TNF-alpha, IL-1 beta, and IFN-beta mRNA. Calyculin A, in the absence or presence of LPS, resulted in sustained tyrosine phosphorylation of the MAP kinases. These findings suggest that an "early" serine/threonine phosphatase activity is essential for LPS stimulation of M phi and that the activation of MAP kinases is not sufficient for the induction of these immediate-early genes. The requirement for a "late" phosphatase activity for expression of a subset of LPS-inducible genes dissociates at least two regulatory pathways in LPS signal transduction.
Enhancement by the complement membrane attack complex of tumor necrosis factor-alpha-induced endothelial cell expression of E-selectin and ICAM-1.
Authors: Kilgore K S , Shen J P , Miller B F , Ward P A , Warren J S 
Published: December 2022

Abstract
Although TNF-alpha and several products of the activated complement system (e.g., C3b, iC3b, and C5a) are known to modulate endothelial cell function in vitro, relatively little is known about the potential modulatory role of the membrane attack complex (MAC) in endothelial cell activation. Using an in vitro neutrophil-endothelial adhesion assay and a quantitative whole cell ELISA to measure endothelial E-selectin and intracellular adhesion molecule-1 (ICAM-1) expression, we examined the modulatory role of the MAC in TNF-alpha-induced neutrophil-endothelial cell adhesive interactions. Activation of quiescent human umbilical vein endothelial cells (HUVECs) with TNF-alpha results in a concentration-dependent increase in neutrophil adhesion measured at 4 h. Assembly of sublytic concentrations of the MAC on endothelial cells did not result in changes in neutrophil-HUVEC adhesion measured at 4 h. Activation of HUVECs with TNF-alpha followed by assembly of the MAC resulted in a marked increase in neutrophil binding as compared with that observed in cells treated with TNF-alpha alone. Blocking studies of mAb revealed that in either TNF-alpha-stimulated or TNF-alpha and MAC-activated endothelial cells enhanced neutrophil binding was nearly entirely attributable to E-selectin and ICAM-1. This conclusion was further supported by a whole-cell ELISA, which provided evidence that the MAC augments TNF-alpha-induced up-regulation of both E-selectin and ICAM-1. This study provides data that support the conclusion that the distal complement system (MAC) can enhance TNF-alpha-induced proinflammatory endothelial cell functions.
Expression, purification, and characterization of the recombinant proform of eosinophil granule major basic protein.
Authors: Popken-Harris P , McGrogan M , Loegering D A , Checkel J L , Kubo H , Thomas L L , Moy J N , Sottrup-Jensen L , Snable J L , Kikuchi M T 
Published: December 2022

Abstract
The cDNA for the highly toxic eosinophil granule major basic protein (MBP) encodes a 25-kDa acidic precursor (proMBP) that is processed to form the 14-kDa mature MBP. To characterize the biochemical and biological properties of proMBP, and compare these to the known properties of MBP, we expressed recombinant proMBP in Chinese hamster ovary cells and purified the secreted form from supernatants. We developed a mAb specific for proMBP, J163-15E10, and by using a proMBP-specific RIA we found that recombinant proMBP was expressed quite efficiently at levels between 10 and 100 mg/l. By SDS-PAGE and immunoblotting analyses of bulk Chinese hamster ovary supernatants, recombinant proMBP was electrophoretically heterogeneous with an apparent molecular mass ranging from 3 x 10(4) to 1 x 10(5) daltons. Despite difficulties encountered because of the extreme molecular heterogeneity of the proform, two methods for purification of a predominant 33-kDa form of recombinant proMBP are presented. Glycosylation analysis of purified 33-kDa proMBP indicated that approximately 5 kDa is likely accounted for by the addition of one glycosaminoglycan group, three O-linked, and one N-linked complex type carbohydrate groups. Functional studies of purified recombinant proMBP were also conducted. Using amounts of proMBP determined to be optimal for MBP activity, it was shown that proMBP not only lacked the ability to inhibit protein synthesis in K562 cells, but it also lacked the ability to stimulate basophil histamine release or generate neutrophil superoxide anion release. Furthermore, proMBP inhibited in a dose-responsive manner the basophil histamine release and superoxide anion generation stimulated by MBP. The development of a mAb and RIA specific for proMBP will now make it possible to analyze biologic fluids for the presence of this protein, especially in pregnancy, when proMBP is increased.
Analysis of V beta 8.2 CDR3 sequences from spinal cord T cells of Lewis rats vaccinated or treated with TCR V beta 8.2-39-59 peptide.
Authors: Buenafe A C , Vainiene M , Celnik B , Vandenbark A A , Offner H 
Published: December 2022

Abstract
Experimental autoimmune encephalomyelitis (EAE) in the Lewis rat can be induced with the administration of Gp-BP. This disease appears to be mediated at least in part by V beta 8.2+CD4+T cells, which specifically recognize the BP72-89 encephalitogenic peptide. Treatment or protection with V beta 8.2 CDR2 39-59 peptide can suppress or prevent clinical signs of EAE, presumably through the activation of regulatory T cells. Interestingly, V beta 8.2+ T cells continue to persist in the spinal cord of protected animals, although their appearance in the central nervous system (CNS) is delayed when compared with control animals with EAE. As part of our effort to elucidate the mechanism(s) of peptide protection and therapy, we sought to determine whether the V beta 8.2+ T cells in the spinal cord of protected or treated rats were truly representative of those found in rats with clinical EAE. Therefore, we examined the following CNS samples for the Asp96Ser97 motif, which has been identified previously in V beta 8.2+ BP-specific, encephalitogenic T cell clones: 1) rats protected with V beta 8.2-39-59 peptide, 2) rats treated with V beta 8.2-39-59 peptide, and 3) control rats with EAE. Our findings indicate that EAE-associated V beta 8.2+ sequences can still be found in both peptide-treated and peptide-protected rats. It appears that administration of V beta 8.2 CDR2 peptide does not prevent EAE-associated V beta 8.2+ T cells from infiltrating the CNS and that other mechanisms are at work to prevent the development of EAE.
Acute graft-versus-host reaction can be aborted by blockade of costimulatory molecules.
Authors: Hakim F T , Cepeda R , Gray G S , June C H , Abe R 
Published: December 2022

Abstract
Injection of parental lymphocytes into an unirradiated adult F1 host results in an acute GVH reaction characterized by immune deficiency, attack on host lymphohematopoietic tissues, and repopulation with donor-derived cells. All of these events result from the initial activation of donor lymphocytes by host alloantigens. Interaction of pairs of host and donor costimulatory molecules, in particular CD28/CTLA4 and B7-1/B7-2, play a crucial role in this initial activation of donor T cells. We demonstrate here that in vivo treatment of the host with high doses of CTLA4-Ig solely during the initial period of donor alloactivation can completely abort the subsequent development of GVH reaction. Although donor T cells are retained, CTLA4-Ig treatment reduces the initial endogenous cytokine production and arrests the subsequent expansion of donor T cells, the differentiation of anti-host effectors, and the development of severe immune deficiency. This result is consistent with the establishment of host-specific tolerance in the donor population, while maintaining host immune competence.
Ly-6C is a marker of memory CD8+ T cells.
Authors: Walunas T L , Bruce D S , Dustin L , Loh D Y , Bluestone J A 
Published: December 2022

Abstract
This study examined long-term phenotypic and functional effects of TCR ligation in vivo. Flow cytometric analysis of T cells from mice treated with anti-CD3 revealed an increase in CD44 expression in both the CD4+ and CD8+ populations. The phenotypic changes were a result of TCR engagement, because treatment with staphylococcal enterotoxin B (SEB) resulted in a preferential increase in CD44 expression on the SEB-reactive V beta 8 T cells. In addition, the percentage of cells expressing Ly-6C increased among the CD8+ subset after anti-CD3 treatment and in the V beta 8+ CD8+ subset after treatment with SEB. Finally, the TCR transgenic (Tg) mouse strain 2C was used to confirm that the phenotypic changes can be induced by exposure to a physiologic ligand (H-2Ld). Before treatment, nearly all of the Tg+CD8+ cells were CD44low/Ly-6C-. Tg+ peritoneal exudate T cells isolated from mice challenged with P815 cells (H-2Ld) up-regulated Ly-6C and secreted higher levels of IFN-gamma on a per Tg+ CD8+ T cell basis after treatment. Taken together, these data indicate that in vivo TCR/CD3 engagement results in phenotypic and functional changes in T cells. Furthermore, Ly-6C expression correlates with an increase in IFN-gamma production after antigenic stimulation of CD8+ T cells, suggesting that it is a "memory" marker that correlates with Ag-specific functional changes in CD8+ T cells.
Identification of heavy chain residues in a humanized anti-CD3 antibody important for efficient antigen binding and T cell activation.
Authors: Zhu Z , Carter P 
Published: December 2022

Abstract
A previously identified humanized anti-CD3 Ab variant, v9, binds T cells with &gt; 100-fold higher efficiency than the original variant, v1, and almost as efficiently as a chimeric molecule containing corresponding murine variable domains. Variants v1 and v9 differ at six positions in the H chain second CDR. Here a mutational analysis was used to identify which of these six replacements are primarily responsible for the difference in binding efficiency. These anti-CD3 variants were used to probe the relationship between Ag binding efficiency and potency in stimulating T cell proliferation. The human to mouse mutations T57S and V63F increase the binding efficiency of variant v1 for T cells by 8- and 12-fold, respectively, and together in variant M18 enhance binding by 26-fold to within 4-fold of variant v9. A framework mutation, 169L, was identified that enhances the binding of variants v1 and M18 by 14- and 3-fold, respectively. The Ag binding efficiencies of anti-CD3 variants correlate directly with their potencies in stimulating the proliferative activity of both resting human PBMC and IL-2-activated human T lymphocytes. Humanized variant v9 is equipotent to the murine parent Ab in stimulating ATL activity. PBMC activated by variants v1 and v9 IgG in a short term culture are equally cytotoxic against human breast carcinoma cells. Thus, high efficiency Ag binding by anti-CD3 variants is important for stimulating efficient T cell proliferation, but not cytotoxicity, in vitro.
The Ig heavy chain switch region is a hotspot for insertion of transfected DNA.
Authors: Baar J , Shulman M J 
Published: December 2022

Abstract
The Ig heavy chain class switch usually occurs by breaking and rejoining DNA in the switch (S) regions, which consist of tandemly repeated sequences 5' of the constant region exons. Various studies have suggested that S DNA can also recombine with non-S sequences. To measure the frequency of such recombination events, the hybridoma cell line igm692, a deletion mutant that lacks the C mu 1 and C mu 2 exons and the 3' end of the S mu region, was transfected with a fragment bearing the C mu 1-2 exons, but no S mu DNA. Insertion of this fragment into the residual VDJ-C mu intron of igm692 can restore a functional mu gene, yielding a transformant that is detected as a plaque-forming cell (PFC). PFC comprise approximately 8 x 10(-7) of the surviving transfected cells. In 10 of 12 PFCs, the C mu 1-2 fragment inserted into the 2.5-kb residual S mu region, whereas insertion in two cases occurred in the 3.5-kb segment 5' of S mu. Using a PCR assay to measure the frequency of insertion of the transferred fragment elsewhere in the hybridoma genome, we found that approximately 9% of the surviving transfected cells had stably acquired the C mu 1-2 fragment. These results indicate that the S mu region is approximately 100-fold more recombinogenic than the average genomic site, and approximately 7-fold more recombinogenic than the non-S mu segment of the residual VDJ-C mu, i.e., the S mu region is a hotspot for insertion of transfected DNA.
Bacterial infection of the testis leading to autoaggressive immunity triggers apparently opposed responses of alpha beta and gamma delta T cells.
Authors: Mukasa A , Hiromatsu K , Matsuzaki G , O'Brien R , Born W , Nomoto K 
Published: December 2022

Abstract
The mechanisms that lead to the breakdown of self-tolerance and testis-specific immune reactivity in the murine orchitis model are understood only in part. We investigated the histopathologic and immunologic consequences of a unilateral bacterial (Listeria monocytogenes) infection of the testis. Both infected and contralateral sides of this bilateral organ suffered severe inflammatory responses despite a conspicuous absence of bacteria in the contralateral tissue. Also, in both testicles, T cell populations increased, involving both alpha beta and gamma delta T cell subsets. Concomitant with the bilateral orchitis, testis-specific delayed type hypersensitivity and Ab responses developed. Ab depletion experiments indicated that in this orchitis model, as in others, alpha beta T cells are initiators of the autoaggressive reactivity. In contrast, Ab depletion of gamma delta T cells accelerated the inflammatory response in both testicles, suggesting a regulatory role for this type of T cells in both infection-induced and autoimmune orchitis.