bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel function-associated molecule related to non-MHC-restricted cytotoxicity mediated by activated natural killer cells and T cells.
Authors: Garni-Wagner B A , Purohit A , Mathew P A , Bennett M , Kumar V 
Published: December 2022

Abstract
NK cells and IL-2-propagated splenic T cells mediate non-MHC-restricted cytotoxicity. The molecules involved in this process are not well defined. We describe a novel 66-kDa cell surface molecule called 2B4 that is expressed on cells that mediate non-MHC-restricted cytotoxicity. All resting and rIL-2 cultured NK cells and a significant number of T cells cultured in high doses of rIL-2 are 2B4+. In fresh as well as cultured spleen cells, all non-MHC-restricted cytotoxicity is contained within the 2B4+ population. In addition to defining cells capable of non-MHC-restricted killing, the 2B4 molecule is also involved in modulation of their function. In the presence of anti-2B4, the lytic activity of cultured NK cells and non-MHC-restricted T cells against a wide variety of FcR- and FcR+ targets is greatly augmented. Anti-2B4 is also able to transduce other signals in IL-2-activated NK cells such as IFN-gamma secretion and granule exocytosis. In addition, 2B4+ T cells can specifically lyse the 2B4 hybridoma cells. Unlike many other activation and adhesion molecules (such as murine CD2, LFA-1, and CD16), 2B4 expression is restricted to cells that mediate NK-like killing. Conversely, highly activated T cells that do not express 2B4 do not mediate non-MHC-restricted killing. Together these data suggest that the 2B4 molecule is likely to be a part of a receptor complex or a component of signal-transducing complex on cells that mediate non-MHC-restricted killing.
Effects of purified dietary n-3 ethyl esters on murine T lymphocyte function.
Authors: Fowler K H , Chapkin R S , McMurray D N 
Published: December 2022

Abstract
To precisely determine the biologic role of fish oil-derived constituents (n-3 polyunsaturated fatty acids), it is imperative that information on highly purified n-3 polyunsaturated fatty acids be evolved. Therefore, we studied the effects of a low dose, short term dietary supplementation with highly purified (n-3) ethyl esters with regard to murine T lymphocyte function. A 10-day dietary supplementation with low dose, highly purified (n-3) fatty acid ethyl esters was examined for effects on murine splenic lymphocyte function and membrane composition. Mice were fed diets containing either 3% safflower oil (SAF) ethyl esters, 2% SAF plus 1% eicosapentaenoic acid ethyl esters (EPA) (99% pure), or 2% SAF plus 1% docosahexaenoic acid ethyl esters (DHA) (97% pure). Fatty acid analysis of the lymphocyte membranes showed that membrane compositions of the EPA- and DHA-fed mice were subsequently enriched with these (n-3) fatty acids. Con A-induced lymphoproliferative assays (Con A, 5 and 10 micrograms/ml) revealed that splenic lymphocytes from the EPA group had significantly higher mitogenic responses relative to lymphocytes from the DHA or SAF groups (p &lt; 0.05). In contrast, DHA splenocytes had the highest level of 3H-labeled diradylglycerol as a percentage of total lipid. Macrophage-lymphocyte co-cultures demonstrated that the dietary effect on proliferation in response to Con A was influenced by lymphocyte source, but apparently not by macrophage source. In addition, cells from Mycobacterium bovis vaccine-vaccinated mice were placed in culture with purified protein derivative (PPD) (10, 20, and 40 micrograms/ml), as well as Con A (5 and 10 micrograms/ml) to allow comparison between mitogenic and antigenic stimulation. No statistically significant differences (p &gt; 0.05) existed between the diet groups upon PPD stimulation. However, lymphocytes from the DHA group exhibited significantly higher proliferative responses to Con A than cells from the EPA and SAF groups (p &lt; 0.05). M. bovis vaccine-immunized EPA and DHA fed mice also exhibited significantly reduced delayed-type hypersensitive reactivity to footpad testing with PPD in comparison to that demonstrated by SAF-fed mice (p &lt; 0.05). EPA-fed mice demonstrated the most decreased response. Overall, this study demonstrates for the first time that: 1) low dose, short term dietary supplementation with highly purified EPA or DHA can modulate select functional and transmembrane signaling responses of murine splenic lymphocytes; and 2) that these dietary agents have differing effects on mitogen vs Ag receptors.
The Peyer's patch high endothelial receptor for lymphocytes, the mucosal vascular addressin, is induced on a murine endothelial cell line by tumor necrosis factor-alpha and IL-1.
Authors: Sikorski E E , Hallmann R , Berg E L , Butcher E C 
Published: December 2022

Abstract
The specificity of lymphocyte homing from the blood into a tissue is determined in part by complementary pairs of adhesion receptors on lymphocytes and endothelial cells termed homing receptors and vascular addressins, respectively. The mucosal vascular addressin involved in lymphocyte homing to Peyer's patches is a 66-kDa glycoprotein, MAdCAM-1. Investigation of the regulation and molecular genetics of MAdCAM-1 have been hampered by the lack of a murine cell line expressing this adhesion molecule. We show herein using indirect immunofluorescence studies that MAdCAM-1 can be induced on a murine endothelial cell line, bEnd.3, by cytokines and LPS. Western blot analysis of MAdCAM-1 purified by affinity column chromatography from TNF-alpha-treated bEnd.3 cells demonstrates a 66-kDa protein that comigrates in SDS-PAGE with the MAdCAM-1 constitutively found on high endothelial venules in murine mesenteric lymph nodes. Comparison of MAdCAM-1 expression on the bEnd.3 cells was made to the expression of adhesion molecules ICAM-1 and VCAM-1. MAdCAM-1 and VCAM-1 are not constitutively expressed on the bEND.3 surface but can be induced in a concentration-dependent manner by LPS, TNF-alpha, and IL-1. ICAM-1 is constitutively expressed on the endothelioma surface and expression is increased by TNF-alpha, IL-1, LPS, and IFN-gamma. Surface expression of MAdCAM-1 peaks 12 to 18 h after exposure to TNF-alpha and remains elevated at 48 h, whereas expression of VCAM-1 peaks at 4 h and inducible ICAM-1 peaks between 4 and 18 h. Interestingly, IFN-gamma has differential effects on expression of these three adhesion receptors. IFN-gamma alone induces VCAM-1 and enhances ICAM-1 expression, but does not induce MAdCAM-1. Furthermore, although, preincubation of bEND.3 cells with IFN-gamma modestly increases the induction of ICAM-1 and VCAM-1 in response to TNF-alpha and IL-1, it dramatically reduces the TNF-alpha, IL-1, and LPS-induced expression of MAdCAM-1. MAdCAM-1 on bEnd.3 cells is functional as the murine T lymphoma TK1, known to bind MAdCAM-1, also binds to TNF-alpha-stimulated endothelioma but not to unstimulated cells. This binding is blocked by the antibodies against MAdCAM-1 and against the alpha 4-chain of its integrin receptor, alpha 4 beta 7, on TK1 cells.(ABSTRACT TRUNCATED AT 400 WORDS)
Identification of tropomyosin as the major shrimp allergen and characterization of its IgE-binding epitopes.
Authors: Shanti K N , Martin B M , Nagpal S , Metcalfe D D , Rao P V 
Published: December 2022

Abstract
The major heat-stable shrimp allergen (designated as Sa-II), capable of provoking IgE-mediated immediate type hypersensitivity reactions after the ingestion of cooked shrimp, has been shown to be a 34-kDa heat-stable protein containing 300 amino acid residues. Here, we report that a comparison of amino acid sequences of different peptides generated by proteolysis of Sa-II revealed an 86% homology with tropomyosin from Drosophila melanogaster, suggesting that Sa-II could be the shrimp muscle protein tropomyosin. To establish that Sa-II is indeed tropomyosin, the latter was isolated from uncooked shrimp (Penaeus indicus) and its physicochemical and immunochemical properties were compared with those of Sa-II. Both tropomyosin and Sa-II had the same molecular mass and focused in the isoelectric pH range of 4.8 to 5.4. In the presence of 6 M urea, the mobility of both Sa-II and shrimp tropomyosin shifted to give an apparent molecular mass of 50 kDa, which is a characteristic property of tropomyosins. Shrimp tropomyosin bound to specific IgE antibodies in the sera of shrimp-sensitive patients as assessed by competitive ELISA inhibition and Western blot analysis. Tryptic maps of both Sa-II and tropomyosin as obtained by reverse phase HPLC were superimposable. Dot-blot and competitive ELISA inhibition using sera of shrimp-sensitive patients revealed that antigenic as well as allergenic activities were associated with two peptide fractions. These IgE-binding tryptic peptides were purified and sequenced. Mouse anti-anti-idiotypic antibodies raised against Sa-II specific human idiotypic antibodies recognized not only tropomyosin but also the two allergenic peptides, thus suggesting that these peptides represent the major IgE binding epitopes of tropomyosin. A comparison of the amino acid sequence of shrimp tropomyosin in the region of IgE binding epitopes (residues 50-66 and 153-161) with the corresponding regions of tropomyosins from different vertebrates confirmed lack of allergenic cross-reactivity between tropomyosins from phylogenetically distinct species.
The utilization of individual VH exons in the primary repertoire of adult BALB/c mice.
Authors: Sheehan K M , Mainville C A , Willert S , Brodeur P H 
Published: December 2022

Abstract
The utilization of VH gene families is severely biased during fetal development, such that D-region proximal VH genes are overrepresented. After birth the VH repertoire becomes more equally representative of the total inherited set of functional VH genes. To investigate the extent of this normalization process, we have determined the relative utilization of individual VH exons in the pre-immune repertoire of adult BALB/c spleen cells. Large samples of IgM heavy chain transcripts from polyclonally activated B cells were captured in a cDNA phage library and screened by hybridization using highly specific oligonucleotide probes. These studies revealed that the utilization of particular VH exons can differ by an order of magnitude. Significantly, the VH genes most under-represented in the pre-immune repertoire are located in the region of the Igh locus most distal to the DjhCh region. We suggest that the chromosomal position of a particular VH gene may influence its utilization and that the normalization of the adult repertoire is incomplete.
Kinetics of E2A basic helix-loop-helix-protein expression during myelopoiesis and primary B cell differentiation.
Authors: Xin X Q , Nelson C , Collins L , Dorshkind K 
Published: December 2022

Abstract
The DNA-binding factors encoded by the E2A gene, which include the basic helix-loop-helix proteins E12 and E47, are thought to regulate Ig gene expression. In the rat these factors are products of the Pan locus and are referred to as Pan-2 and Pan-1, respectively. To determine when during B cell differentiation Pan (E2A) DNA-binding proteins are first expressed, cells from a newly developed rat long term lymphoid bone marrow culture system were analyzed molecularly and phenotypically using a newly defined anti-Pan mAb. The data indicate that Pan-expressing cells appear in B cell progenitors before the appearance of the CD45R B lineage-associated Ag or microH chain protein. The results also indicate that Pan proteins are present in cells that had undergone D-JH rearrangements. Finally, although Pan (E2A) proteins are present in myeloid precursors, expression is extinguished as differentiation into mature myeloid cells occurs.
Regulation of eosinophil migration by adult T cell leukemia-derived factor.
Authors: Hori K , Hirashima M , Ueno M , Matsuda M , Waga S , Tsurufuji S , Yodoi J 
Published: December 2022

Abstract
Adult T cell leukemia-derived factor (ADF), originally defined as an IL-2 receptor alpha-chain (IL-2R alpha)/p55 (Tac) inducer, is a human thioredoxin homologue and has many cytokine-like activities. In this study, we examined the regulatory effect of ADF on eosinophil migration using human eosinophils and an eosinophilic subline of HL-60 human promyelocytic leukemia cells, YY-1. rADF induced migration of eosinophils from patients with hypereosinophilia, although rADF exhibited little activity on eosinophils from healthy donors. When human eosinophils were incubated with rADF (0.1-10 micrograms/ml) at 37 degrees C for 24 h, both chemotactic and chemokinetic activity of the complement anaphylatoxin peptide C5a on eosinophil migration was markedly enhanced in a dose-dependent manner. Similarly, this enhancing effect of rADF was observed in the migration assay using YY-1 cells. In contrast, rADF showed no modulation of migratory behavior of human eosinophils and YY-1 cells by IL-3, IL-5, nor granulocyte-macrophage colony-stimulating factor. Scatchard analysis of C5a receptors on YY-1 cells using 125I-C5a showed that rADF modulated neither the density nor the affinity of the cell membrane significantly. Furthermore, mutant ADF (mADF), which had no reducing activity, had no enhancing effect on C5a-induced eosinophil migration. These results indicate a possible involvement of ADF in the recruitment of eosinophils through redox regulation by a dithiol reductase activity.
Functional molecular complexes of human N-formyl chemoattractant receptors and actin.
Authors: Jesaitis A J , Erickson R W , Klotz K N , Bommakanti R K , Siemsen D W 
Published: December 2022

Abstract
When human neutrophils become desensitized to formyl peptide chemoattractants, the receptors (FPR) for these peptides are converted to a high affinity, GTP-insensitive form that is associated with the Triton X-100-insoluble membrane skeleton from surface membrane domains. These domains are actin and fodrin-rich, but G protein-depleted suggesting that FPR shuttling between G protein-enriched and depleted domains may control signal transduction. To determine the molecular basis for FPR interaction with the membrane skeleton, neutrophil subcellular fractions were screened for molecules that could bind photoaffinity-radioiodinated FPR solubilized in Triton X-100. These receptors showed a propensity to bind to a 41- to 43-kDa protein band on nitrocellulose overlays of SDS-PAGE-separated cytosol and plasma membrane fractions of neutrophils. This binding, as well as FPR binding to purified neutrophil actin, was inhibited 50% by 0.6 microM free neutrophil cytosolic actin. Addition of greater than 1 microM G-actin to crude or lectin-purified Triton X-100 extracts of FPR from neutrophil membranes increased the sedimentation rate of a significant fraction of FPR two to three fold as measured by velocity sedimentation in Triton X-100-containing linear sucrose density gradients. Addition of anti-actin antibodies to FPR extracts caused a concentration-dependent immunoprecipitation of at least 65% of the FPR. More than 40% of the immunoprecipitated FPR was specifically retained on protein A affinity matrices. Membrane actin was stabilized to alkaline washing when membranes were photoaffinity labeled. Conversely, when purified neutrophil cytosolic actin was added to membranes or their digitonin extracts, after prior depletion of actin by an alkaline membrane wash, photoaffinity labeling of FPR was increased two- to fourfold with an EC50 of approximately 0.1 microM actin. We conclude that FPR from human neutrophils may interact with actin in membranes to form Triton X-100-stable physical complexes. These complexes can accept additional G-actin monomers to form higher order molecular complexes. Formation of FPR-actin complexes in the neutrophil may play a role in the regulation of chemoattractant-induced activation or actin polymerization.
Expression of a TNF inhibitor in transgenic mice.
Authors: Peppel K , Poltorak A , Melhado I , Jirik F , Beutler B 
Published: December 2022

Abstract
We previously reported that a chimeric protein consisting of the human p55 TNF receptor covalently linked to a murine IgG1 Fc heavy chain acts as an efficient TNF inhibitor, as a result of its high binding affinity for native TNF trimers of both murine and human origin. A transgenic mouse line constitutively expressing the inhibitor from a cytomegalovirus promoter was established. All organs examined expressed the transgene. TNF inhibitory activity was easily detected in plasma of transgenic animals but not in plasma of nontransgenic littermates. This founder line was not found to have any obvious phenotype. Specifically, transgenic mice born to wild-type or transgenic females were indistinguishable from nontransgenic littermates with respect to their size at birth, at three months and at six months of age, with respect to the size and morphology of their lymphoid organs and with respect to their hematocrit, white blood cell count, and differential. Although TNF is known to be constitutively expressed by cells of the thymus and trophoblast, the lack of a clear phenotype in association with the constitutive expression of a TNF inhibitor suggests that TNF may be dispensable in early development.
Activated eosinophils evoke chloride secretion in model intestinal epithelia primarily via regulated release of 5'-AMP.
Authors: Resnick M B , Colgan S P , Patapoff T W , Mrsny R J , Awtrey C S , Delp-Archer C , Weller P F , Madara J L 
Published: December 2022

Abstract
Eosinophils may be prominent in intestinal diseases including allergic gastroenteritis, inflammatory bowel disease, enteritis associated with hypereosinophilic syndromes (HES), and parasitic diseases. Unlike normal blood eosinophils, those that circulate in HES and those that infiltrate inflamed tissue exhibit an "activated" phenotype. To model intestinal epithelial-eosinophil interactions, we used peripheral blood eosinophils and human crypt-like T84 epithelial cell-line monolayers. Eosinophils from normal, mildly atopic donors, only if activated by PMA or primed with granulocyte-macrophage-CSF for 48 h, as well as eosinophils from HES patients elicited a short circuit current when applied apically to T84 monolayers. This eosinophil-derived bioactivity, which was transferable in cell-free supernatants and in &lt; 1000 m.w. ultrafiltrates, stimulated electrogenic Cl- secretion, as indicated by inhibition with basolateral bumetanide or gluconate substitution and by enhancement of the rate constant for 125I efflux from preloaded T84 cells. This secretagogue activity was blocked in both intact activated eosinophils and in eosinophil-conditioned supernatants, by 8-phenyl-theophylline, indicating involvement of an adenosine receptor. Ion exchange and reversed-phase HPLC analyses demonstrated that eosinophil supernatant ultrafiltrates contained elevated levels of 5'-AMP that was converted to adenosine after incubation with epithelium. Inhibition of epithelial apical membrane ecto-5'-nucleotidase ablated the conversion to adenosine. These studies establish that activated eosinophils elicit Cl- secretion from intestinal epithelial and that 5'-AMP released by eosinophils followed by its conversion to adenosine at the epithelial surface is the basis for this response.
Oral tolerance in experimental autoimmune uveoretinitis. Distinct mechanisms of resistance are induced by low dose vs high dose feeding protocols.
Authors: Gregerson D S , Obritsch W F , Donoso L A 
Published: December 2022

Abstract
Studies of oral tolerance in LEW rat models of autoimmune diseases including S-antigen (S-Ag)-mediated experimental autoimmune uveoretinitis (EAU), and myelin basic protein-induced experimental autoimmune encephalomyelitis have produced conflicting evidence for the roles of clonal anergy and suppression. Using subpeptides from a region of S-Ag known to induce oral tolerance a protective site was localized to a nonamer of residues 347-355. This site was also uveitogenic, providing the basis for testable hypotheses for tolerance to be due to clonal anergy in pathogenic T cells specific for that site, or to suppression. Evidence for suppression was strongly supported by several observations. 1) Induction of oral tolerance with low dose feedings (250 micrograms/feeding) of peptide 343-362 conferred resistance to EAU induction by intact S-Ag, which should not be possible if only T cells specific for epitopes in 343-362 were rendered unresponsive, since there are several other pathogenic sites in S-Ag. 2) Low dose feeding induced resistance to EAU induction by a distinct, spatially separate peptide, residues 270-289, of S-Ag. 3) The requirement for linked recognition was shown by the inability of tolerance induced by feeding 343-362 to protect from EAU induction by a peptide, residues 521-540, derived from interphotoreceptor retinoid binding protein, a different uveitogenic retinal protein. 4) Resistance could be adoptively transferred. Conversely, induction of tolerance with high doses of peptide (5 mg/feeding) resulted in loss of resistance to EAU induced by S-Ag, although disease induction by the fed peptide was inhibited; observations that are consistent with clonal anergy. The apparent lack of suppression after high dose feeding could mean that suppressor T cells can also be rendered unresponsive or that induction of T suppressor cells is dependent on CD4+ Th cells, which were rendered anergic, leading to lack of T suppressor development. We suggest that oral tolerance operates by at least two distinct mechanisms that depend on the feeding dose; low doses induce suppression, whereas high doses induce unresponsiveness.
Identification of human pre-T/NK cell-associated genes.
Authors: Ranes-Goldberg M G , Hori T , Mohan-Peterson S , Spits H 
Published: December 2022

Abstract
We have used a combination of subtractive cloning and differential screening techniques to identify genes preferentially expressed in early stages of human T/NK cell development compared with mature T and NK cells. A fetal liver-derived cytoplasmic (c) CD3+ membrane (m) CD3- clone, FL508, which expresses markers characteristic of pre-T and pre-NK cells served as a cell source for our cloning experiments. A cDNA library enriched for genes expressed in FL508 was constructed by removal of cDNA that hybridized to mRNA from a B cell line, JY. One-tenth of the resulting library of 5000 clones was screened by differential hybridization with cDNA probes from JY and a mature CD4+ T cell clone, B21. The relative expression levels of six selected clones were analyzed in 17 different cell/tissue types by semiquantitative polymerase chain reaction. Four of these clones are expressed at higher levels in thymocytes than in mature T or NK cells, and three clones are expressed at higher levels in fetal liver cells than in either mature T or NK cells. Partial and complete DNA sequence information suggests that these six cDNA correspond to previously unidentified genes. Genes identified in this study may be useful not only as markers for early stages of T/NK cell ontogeny, but also as tools for understanding novel developmental events.