bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of C-reactive protein by alveolar macrophages.
Authors: Dong Q , Wright J R 
Published: December 2022

Abstract
C-reactive protein (CRP) is well characterized as one of the serum acute phase proteins, the levels of which increase dramatically after infection. CRP has been shown to be involved in multiple immunoregulatory functions. For example, it activates the classical complement cascade, opsonizes bacteria for phagocytosis, and stimulates phagocytic cells. Although CRP is predominantly produced and secreted by hepatocytes, other cells including subsets of lymphocytes, Kupffer cells, and blood monocytes have been shown to synthesize this protein as well. We hypothesized that CRP may be produced in the lung, and therefore it could function directly in pulmonary host defense. Western blot analysis showed that CRP was present in the lung tissue, lung lavage, and alveolar macrophages. This result was further confirmed by immunohistochemical staining of lung sections that showed the localization of CRP in alveolar macrophages. The CRP mRNA was detected subsequently by reverse-transcriptase PCR (RT-PCR), and a single amplified product was obtained from alveolar macrophages as well as from whole lung tissue. Both were the same size as the amplified product obtained from liver mRNA. Furthermore, in situ hybridization with CRP riboprobe demonstrated specific staining of alveolar macrophages both in lung sections and isolated cells. In addition, in situ hybridization showed that CRP mRNA levels in isolated alveolar macrophages were up-regulated by in vitro LPS stimulation. In summary, these results indicate that CRP is produced by alveolar macrophages, and suggest that CRP may be involved in the pulmonary immune response.
IL-13 released by and localized in human basophils.
Authors: Li H , Sim T C , Alam R 
Published: December 2022

Abstract
We and others have shown that human basophils can synthesize and release IL-4. However, IL-13, a cytokine that closely resembles IL-4, has not hitherto been described as a basophil product. The production of IL-13 by basophils was demonstrated by immunocytochemistry. Approximately 70% of basophils stimulated with anti-FcepsilonRIalpha (antibody to the alpha subunit of IgE receptor type I) stained for IL-13. Under similar experimental conditions, mononuclear cells failed to stain for IL-13. The cytokine was localized to basophilic granules by electron microscopic examination of immunogold staining. The secretion of IL-13 into the culture supernatant was assayed by ELISA. Kinetic studies showed detectable IL-13 release at 3 h, which steadily increased up to 24 h. This is significantly different from the kinetics of basophil histamine and IL-4 release. IL-13 production was also observed upon stimulation with anti-IgE, anti-FcepsilonRIalpha, IL-3, and A23187 in a dose-dependent manner. PBMC, neutrophils, and eosinophils isolated from the same donors did not release IL-13 after anti-IgE stimulation. The anti-IgE-induced basophil IL-13 synthesis could be enhanced by IL-3 preincubation (with and without IL-3 preincubation, anti-IgE-induced IL-13 production was 227 +/- 99 and 42 +/- 13 pg/10(6) basophils, respectively). PBMC produced a significant amount of IL-1 3 upon stimulation with PHA, but a low level of IL-13 in response to A23187 and/or PMA. Eosinophils and neutrophils did not produce IL-13 when cultured with A23187, IL-5, and anti-FcepsilonRIalpha. This is the first demonstration of IL-1 3 production by basophils. Our data suggest that basophils, in addition to secreting mediators, can represent an important source of proallergic cytokines.
Functional contributions of the FcepsilonRIalpha and FepsilonRIgamma subunit domains in FcepsilonRI-mediated signaling in mast cells.
Authors: Repetto B , Bandara G , Kado-Fong H , Larigan J D , Wiggan G A , Pocius D , Basu M , Gilfillan A M , Kochan J P 
Published: December 2022

Abstract
The functional contributions of the alpha and gamma subunit domains of the high affinity receptor for IgE (Fcepsilon-RI) were determined following chimeric receptor aggregation. Chimeric receptors of the extracellular (EC) and cytoplasmic tail (CT) domains of FcepsilonRI and the IL-2R p55 subunit (I) were constructed and stably expressed in RBL-2H3 cells. Signaling (inositol phosphate production, tyrosine phosphorylation, Ca2+ mobilization, and secretion of histamine and arachidonic acid metabolites) via alpha/gamma/gamma or I/gamma/gamma was similar to the native rat receptor, and both were shown to associate with endogenous FcepsilonRIbeta and FcepsilonRIgamma subunits. Therefore, the contributions of the EC domains could not be evaluated. The chimeras alpha/I/gamma and I/I/gamma were found to be single polypeptide chains, as they did not associate with beta and gamma. Signaling via alpha/I/gamma resulted in the appearance of biochemical events common to the native receptor. Cross-linking I/I/gamma elicited histamine release, [14C]arachidonic acid metabolites, tyrosine phosphorylation, Ca2+ mobilization, and only inositol trisphosphate production, which were not of a similar magnitude to the native FcepsilonRI. No biochemical events were elicited by cross-linking alpha/I/I or I/I/I. These results demonstrate that both the FcepsilonRIalpha EC domain and the FcepsilonRIgamma CT domain are essential for the FcepsilonRI signaling process, and that while FcepsilonRIIgamma CT plays a critical role in FepsilonRI signaling, the EC domain of FcepsilonRIalpha has a major contribution in signaling, as well as a role in modulating the magnitude of the biochemical events.
Pathogenic role of anti-endothelial cell antibodies in vasculitis. An idiotypic experimental model.
Authors: Damianovich M , Gilburd B , George J , Del Papa N , Afek A , Goldberg I , Kopolovic Y , Roth D , Barkai G , Meroni P L , Shoenfeld Y 
Published: December 2022

Abstract
Idiotypic manipulation of naive mice has previously been used for induction of systemic autoimmune diseases (e.g., antiphospholipid syndrome, systemic lupus erythematosus, and Wegener's granulomatosis). The aim of this study focused on the utilization of this technique to induce the production of anti-endothelial cells Abs (AECA) and autoimmune vasculitis in a murine model. AECA were derived from a Wegener's granulomatosis patient's plasma. IgG was purified by absorption on a proteinase-3 affinity column resulting in the depletion of anti-neutrophil cytoplasmic Ab activity. The absorbed IgG fraction displayed a high titer of AECA as evidenced by a cyto-ELISA against unfixed human umbilical vein endothelial cells. BALB/c mice were actively immunized with the purified AECA. Three months after a boost injection with the human AECA, mice developed endogenous AECA (AB), but not Abs to proteinase-3, cardiolipin, or DNA. Histologic examination of lungs and kidneys revealed both lymphoid cell infiltration surrounding arterioles and venules; as well as deposition of Igs at the outer part of blood vessel walls. This experimental animal model of vasculitis, a product of our method of idiotypic manipulation, provides the first direct proof for the pathogenicity of AECA.
Delineation of IL-5 domains predicted to engage the IL-5 receptor complex.
Authors: Dickason R R , Huston M M , Huston D P 
Published: December 2022

Abstract
IL-5 is an interdigitating homodimeric glycoprotein and a member of the helical bundle family of cytokines. IL-5 is a potent activator of eosinophils and a specific promoter of their differentiation. This activity has implicated IL-5 in the pathogenesis of asthma and allergic disease. A detailed understanding of IL-5 structure and function is required to develop immunomodulators of IL-5-mediated inflammatory responses. We generated a panel of neutralizing anti-IL-5 mAbs which were used to map functional domains on IL-5. In addition, the nucleotide sequences for human IL-5, murine IL-5, rat IL-5, and eight human/murine IL-5 chimeras were engineered and expressed in COS-7 cells. These recombinant cytokines and mAbs were used in TF-1 bioassays to identify five functional epitopes on the tertiary structure of IL-5. Residues responsible for the species-specific activity of human IL-5 were identified with the murine BCL1 bioassay. One set of epitopes cluster around the helix A-loop 2 region, which is predicted to engage the IL-5 receptor beta-chain. The second set of epitopes as well as the species specificity domain cluster around the loop 3-helix D region, which is predicted to engage the IL-5 receptor alpha-chain. Together, these analyses target the A/D helical face of IL-5 as the region involved in receptor engagement.
Inhibition of IFN-stimulated gene expression and IFN induction of cytolytic resistance to natural killer cell lysis correlate with E1A-p300 binding.
Authors: Routes J M , Li H , Bayley S T , Ryan S , Klemm D J 
Published: December 2022

Abstract
Treatment of target cells with IFN induces resistance to NK cell lysis. This process is blocked by expression of E1A gene products in adenovirus (Ad)-infected and Ad-transformed cells. We compared the ability of adenovirus serotype 5 (Ad5) E1A exon 1 mutants to inhibit the induction of cytolytic resistance by IFN and block IFN-stimulated gene expression with their capacity to bind the cellular proteins p105 (retinoblastoma gene product), p107, and p300. E1A mutants that did not express conserved region 3 (CR3; residues 138-184) or contained deletions in the nonconserved regions between residues 26-35 or 86-120, bound p105, p107, and p300 and were not impaired in their capacity to block IFN-stimulated gene expression or IFN's induction of cytolytic resistance. E1A mutants with deletions in CR2 (residues 121-138) could not bind p105 or p107, but blocked IFN-stimulated gene expression and IFN's induction of cytolytic resistance. In contrast, mutants in CR1 or the N-terminal nonconserved region (residues 2, 4-25, and 48-60), which define E1A's binding site for p300, were unable to block either IFN-stimulated gene expression or IFN's induction of cytolytic resistance. We conclude that E1A's capacity to block both IFN-stimulated gene expression and IFN's induction of cytolytic resistance appears to be transduced through a pathway that involves E1A-p300 binding. The capacity of E1A to block IFN's induction of cytolytic resistance is probably secondary to E1A's more general ability to inhibit IFN-stimulated gene expression.
Analysis of antigen binding and idiotypic expression by antibodies with polyglycine-replaced complementarity-determining regions.
Authors: Sompuram S R , Den W , Sharon J 
Published: December 2022

Abstract
We investigated the feasibility and usefulness, for structure-function studies, of removing the side chains of entire complementarity-determining regions (CDRs) of Abs by replacement with polyglycine. The CDRs of a murine Ab specific for p-azophenylarsonate (Ars) were replaced with polyglycine, one CDR at a time and in combinations, by oligonucleotide-directed mutagenesis of the V region genes. Mutant Abs were expressed in transfected hybridoma cells and analyzed for Ars binding and for idiotypic expression. The results suggest that, except for the longest CDRs, polyglycine replacement does not alter the general structure of the Ab molecule. However, for analysis of functional contributions of a CDR, the polyglycine replacement method appears to be most useful for CDRs with extended structures whose replacement by polyglycine does not affect the structure of other parts of the variable regions. In the current studies, such CDRs were CDR1 of the heavy chain (H1) and CDR2 of the light chain (L2). The polyglycine replacement of L2, which does not contain an Ag-contacting residue, allowed the formation of an Ars binding Ab. Furthermore, this mutant Ab revealed previously uncharacterized contributions of L2 to idiotypic expression. Polyglycine replacement of H1 abolished Ars binding as expected, because H1 contains an Ag-contacting residue. However, introduction of the contacting residue (Asn) on the polyglycine-replaced H1 background restored the ability of the Ab to bind Ars. The results suggest that polyglycine replacement of CDRs can provide structural information that complements and extends the information obtained by other methods.
Generation of primary tumor-specific CTL in vitro to immunogenic and poorly immunogenic mouse tumors.
Authors: Liu B , Podack E R , Allison J P , Malek T R 
Published: December 2022

Abstract
This study investigated the generation of primary tumor-specific CTL activity in vitro to several mouse tumors. We report that the development of optimal primary tumor-specific CTL to the P815 mastocytoma, the EL4 thymoma, and the Lewis lung carcinoma is dependent on tumor Ags, on enhancement of T cell costimulation by B7.1, and on exogenous T helper activity in the form of IL-2 and IL-4. A relatively low concentration of IL-2 and IL-4 was required to limit the induction of lymphokine-activated killer cells. In the case of P815, the CTL were directed toward molecularly defined tumor rejection Ags. These primary cultures yielded long term T cell lines that were heterogeneous in fine tumor Ag specificity and in cytokine production.
A20 zinc finger protein inhibits TNF and IL-1 signaling.
Authors: Jäättelä M , Mouritzen H , Elling F , Bastholm L 
Published: December 2022

Abstract
A20 zinc finger protein is a product of a cytokine-induced primary response gene. In this report, we demonstrate that A20 specifically inhibits signal transduction pathways induced by TNF and IL-1, suggesting that it functions as a negative regulator of the cytokine response. Overexpression of A20 in MCF7 breast carcinoma cells or in WEHI-S fibrosarcoma cells inhibits apoptosis induced by TNF, whereas cytotoxicity induced by anti-Fas (anti-CD95); lymphokine-activated killer (LAK) cells, serum starvation, oxidative stress, or okadaic acid is not inhibited. Overexpression of A20 also inhibits TNF-induced activation of phospholipase A2 in a similar dose-dependent manner as it inhibits TNF-mediated apoptosis, whereas it does not affect the activation of phospholipase A2 by anti-Fas. Interestingly, A20 also blocks TNF-induced signal transduction pathways not directly related to the cytotoxicity, namely activation of NF-kappa B and AP-1 transcription factors. Activation of these transcription factors by a functionally related cytokine, IL-1, is also inhibited by A20, whereas activation induced by hydrogen peroxide or phorbol ester is unaffected. Overexpression of A20 does not affect the binding of TNF to its cell surface receptors. These data suggest that A20 functions as a negative regulator of TNF and IL-1, interfering with signal transduction pathways at an early point following receptor binding but before the activation of various second messengers, leading to the wide variety of effects induced by these cytokines.
Extracellular matrix proteins attenuate activation and degranulation of stimulated eosinophils.
Authors: Kita H , Horie S , Gleich G J 
Published: December 2022

Abstract
Cellular adhesion plays an important role in the recruitment and activation of eosinophils. Here, we investigated whether extracellular matrix (ECM) proteins modify effector functions of activated human eosinophils. We coated 96-well plates with laminin or fibronectin and blocked nonspecific protein-binding sites with human serum albumin (HSA). When eosinophils were stimulated with platelet-activating factor (PAF) and incubated in these ECM-coated wells, the eosinophils adhered using both beta 1- and beta 2-integrins. Degranulation of eosinophils adherent to laminin- and fibronectin-coated wells was reduced about 50% compared with cells adherent to uncoated, HSA-blocked wells. Furthermore, these inhibitory effects of laminin and fibronectin were concentration-dependent and secretagogue-specific, that is, degranulation induced by C5a and IL-5 was inhibited while degranulation induced by secretory IgA and PMA was not inhibited. Plasma fibronectin, type I collagen and type IV collagen also inhibited PAF- and C5a-induced eosinophil degranulation, whereas fibrinogen did not. By microscopy, PAF-stimulated eosinophils, adhering to uncoated HSA-blocked wells, appeared elongated with many pseudopods. In contrast, eosinophils adhering to laminin-coated wells appeared oval with few pseudopods. Furthermore, when cells were incubated in laminin-coated wells, PAF-stimulated production of a second messenger, inositol phosphate, was markedly reduced. These findings suggest that ECM protein, such as laminin and fibronectin, attenuate both activation and degranulation of eosinophils and also influence their morphology after stimulation by physiologic secretagogues. Thus, ECM proteins may regulate activation of eosinophils, as they traverse between the peripheral blood and their targets.
The role of nitric oxide in proteoglycan turnover by bovine articular cartilage organ cultures.
Authors: Stefanovic-Racic M , Morales T I , Taskiran D , McIntyre L A , Evans C H 
Published: December 2022

Abstract
Monolayer cultures of articular chondrocytes synthesize large amounts of nitric oxide (NO) following exposure to IL-1. The latter has antianabolic and procatabolic activities on these cells, but little is known about the role, if any, of NO in the integrated metabolic pathways of the chondrocyte. In the present study, the role of endogenously produced NO in both the synthesis and degradation of proteoglycans was investigated for the first time. Bovine articular cartilage slices exposed to 20 U/ml human rIL-1 beta (hrIL-1 beta) synthesized large amounts of NO for 1 to 2 days, after which production fell to a steady state level approximately 20% of the peak value for the remainder of the 14-day incubation. The NO synthase inhibitor, N-monomethyl L-arginine (L-NMA, 1 mM), blocked NO production and enhanced the acute catabolic effects of hrIL-1 beta in cartilage derived from both cartilage derived from both calves and adult animals. However, in late cultures, release of proteoglycans was reduced in the presence of L-NMA. The proteolytic activity in conditioned medium of these cultures (measured as caseinolytic activity) was enhanced by L-NMA; however, this inhibitor did not affect the rates of synthesis of proteoglycans. Although NO is widely assumed to be a mediator of cartilage catabolism, our data suggest that it may instead have an acute protective effect. Whether this effect is maintained chronically is less clear.
Immune or normal gamma delta T cells that assist alpha beta T cells in elicitation of contact sensitivity preferentially use V gamma 5 and V delta 4 variable region gene segments.
Authors: Ptak W , Szczepanik M , Ramabhadran R , Askenase P W 
Published: December 2022

Abstract
In the current study, we confirmed previous findings suggesting that gamma delta T cells were involved in the successful adoptive cell transfer of contact sensitivity (CS) by alpha beta CS-effector T cells. In this study, we used hamster anti-mouse gamma delta-TCR mAb treatment of CS-effector T cells, followed by enrichment and removal of the gamma delta T cells with goat anti-hamster Ig-linked magnetic beads, or by addition of hemolytic rabbit C. This removal of gamma delta T cells abrogated adoptive cell transfers of CS, despite the presence of alpha beta T cells that are known to mediate CS. FACS analysis documented enrichment of gamma delta T cells rising from 1 to 2% of the starting cells, to 60 to 95% of the magnetic bead adherent cells. Adoptive cell transfer of CS was reconstituted by adding back to the alpha beta cells, highly enriched gamma delta cells attached to anti-gamma delta-TCR magnetic beads. Not only were gamma delta-enriched T cells from sensitized mice able to assist immune CS-effector alpha beta T cells, but gamma delta T cells from normal nonimmune mice also had CS-assisting activity, and furthermore, neither were MHC-restricted in this function. Thus, CS-assisting gamma delta T cells were present endogenously in normal mice without prior immunization, and acted without Ag specificity and without MHC restriction, to assist CS-effector alpha beta T cells. Similar studies, with hamster mAbs specific for V gamma and V delta portions of gamma delta-TCR, demonstrated that the gamma delta T cells that assisted the CS-effector alpha beta T cells preferentially expressed V gamma 5 and V delta 4 in their TCR. PCR analysis on extracted mRNA showed that V gamma 5 and V delta 4 gene segments indeed were rearranged and expressed in the sensitized and normal lymph nodes; and one-and two-color FACS analysis of magnetic bead-fractionated cells suggested that V gamma 5 and V delta 4 were expressed on the same T cells. In summary, these results demonstrated that V gamma 5+, V delta 4+, gamma delta T cells were needed to assist alpha beta effector T cells in the adoptive cell transfer of CS.
Physical and functional interactions of protein tyrosine kinases, p59fyn and ZAP-70, in T cell signaling.
Authors: Fusaki N , Matsuda S , Nishizumi H , Umemori H , Yamamoto T 
Published: December 2022

Abstract
The src family protein tyrosine kinases participate in signaling through cell surface receptors that lack intrinsic tyrosine kinase domains. One of the src family kinases, p59fyn (Fyn), plays an important role in the TCR-mediated signaling. Here we report that Fyn becomes associated with the zeta-associated tyrosine kinase, ZAP-70, in a T cell hybridoma upon stimulation. The association was transient; it occurred as early as 10 s after stimulation and disappeared after 10 min. The two proteins were also associated with each other when coexpressed in COS cells. Coexpression of the zeta-chain was not required for their interaction. Mutational analysis of Fyn and ZAP-70 revealed that their kinase activities were relevant to the association. Deletion of both the SH2 and SH3 domains of Fyn resulted in the decrease of the association with ZAP-70. Consistently, Fyn-SH2 and Fyn-SH3 fused to glutathione S-transferase were able to bind to ZAP-70. These data suggest that multiple sites of Fyn and ZAP-70 are involved in the association. Furthermore, coexpression of the wild-type of both kinases in COS cells enhanced tyrosine phosphorylation of the helix-turn-helix-containing protein, HS1. HS1 was also tyrosine phosphorylated upon TCR stimulation. Thus, we propose that Fyn phosphorylates and activates ZAP-70 and that both kinases cooperate in TCR signaling.
Roles of platelet/endothelial cell adhesion molecule-1 (PECAM-1, CD31) in natural killer cell transendothelial migration and beta 2 integrin activation.
Authors: Berman M E , Xie Y , Muller W A 
Published: December 2022

Abstract
Platelet/endothelial cell adhesion molecule-1 (PECAM-1, CD31) is a glycoprotein expressed on the surfaces of monocytes, neutrophils, platelets, a subpopulation of T cells, and, as described in this work, on NK cells. It is also concentrated at the junctions between endothelial cells (EC) in culture, and is expressed on continuous endothelia in all tissues. PECAM has been shown to be involved in monocyte and neutrophil transendothelial migration in vitro and in vivo. The function of PECAM in NK cell interaction with EC has never been studied. In this work, we demonstrate that ligation of PECAM on the surface of NK cells activates their beta 2 integrins. Anti-PECAM Abs added to NK cells caused a 2.5- to 4-fold increase in the binding of these cells to monolayers of EC or 3T3 cells transfected with ICAM-1, and this was inhibited by a mAb against CD18. PECAM also plays a role in NK cell transendothelial migration. Anti-PECAM Abs inhibited 50% of NK cell transmigration through resting EC in an in vitro system. The transmigration of CD56dim and CD56bright cells was inhibited equally. IFN-gamma increased NK cell transmigration; the transmigration of CD56bright cells was increased to a much greater extent than CD56dim transmigration (4-fold vs 1.5-fold). Anti-PECAM inhibited the transmigration of CD56dim cells by 30%, while that of CD56bright cells was not blocked. These studies demonstrate that PECAM-1 could play an important role in the extravasation of NK cells into tissues for constitutive surveillance and into sites of inflammation.