bluuebunny/crossref_metadata_2025_split huggingface dataset:
E-box activator of the C4 promoter is related to but distinct from the transcription factor upstream stimulating factor.
Authors: Galibert M D , Miyagoe Y , Meo T 
Published: January 2023

Abstract
The murine C4 promoter contains a motif (E-C4) active in transcriptional activation whose structure complies with the E-box consensus sequence recognized by the helix-loop-helix transcription factors. This site is found also in human and rat C4 promoters and has the structure (-75) CACGTG (-70) characteristic of the class B subset of b-helix-loop-helix-zipper proteins. We have challenged the hypothesis that the protein factor responsible for the E-C4-mediated transcriptional activation is identical to one of the previously characterized nuclear factors. The molecular mass of the E-C4 factor is slightly bigger than that of Hela upstream stimulating factor (USF) (43/44 kDa). Moreover, the nucleotides immediately adjoining the E-C4 core sequence contribute to the distinctive fine specificity of the E-C4 factor. Optimized USF and MYC DNA-binding sites, which differ in the nucleotides bordering the hexanucleotide box displace the E-C4 factor in competition assays but with lesser efficiency than the E-C4 site itself. Finally, the E-C4 factor fails to exhibit the heat resistance characteristic of USF proteins. The results show that the E-C4 transcription factor has DNA binding properties overlapping those of other helix-loop-helix proteins but is structurally distinct from the factors so far described. Although C4 is not the first liver gene endowed with an E-box-mediated activation, it affords the first example where such activation takes place in the context of a TATA-less promoter, and is functionally linked to an initiator element-dependent transcription.
Few V gene segments dominate the T cell receptor beta-chain repertoire of the human thymus.
Authors: Jores R , Meo T 
Published: January 2023

Abstract
We undertook a large sample census of the TCR-beta repertoire from a single human thymus (300 clones from an unamplified cDNA library), to establish the statistics of the rearranged V, D, J, and C gene segments. The assortments of all germ-line segments are subject to significant biases and thus critically reduce the effective germ-line contribution to beta-chain diversity. Thirty-two V genes characterize the whole sample, but surprisingly as few as seven genes from different families encompass half of the beta-chain repertoire. Furthermore, a Spearman rank order correlation test of the thymic V beta frequencies with those inferred in other studies using RNase protection assays shows a statistically significant similarity. Thus, in the establishment of thymic V beta frequencies in man, rearrangement preferences intrinsic to the progenitors of TCR-beta expressing cells override HLA- and Ag-dependent biasing factors. By implication, a large enough pool of direct progenitor cells (maybe as high as thousands) must exist to secure V beta frequencies against large random fluctuations. Uncorrelated with the V gene bias, the representation of D beta and J beta segments is also far from even. Notably, D beta 1 and J beta 2.1 and 1.2 predominate. Using the above mentioned rank order statistic, we also find that unlike V genes, the bias in the J segment usage carries over into the frequencies of peripheral T lymphocyte populations.
Characterization of the gene for the human high affinity IgE receptor (Fc epsilon RI) alpha-chain.
Authors: Pang J , Taylor G R , Munroe D G , Ishaque A , Fung-Leung W P , Lau C Y , Liu F T , Zhou L 
Published: January 2023

Abstract
The Fc epsilon RI couples the mast cell-surface binding of IgE and Ag to a complex series of intracellular events culminating in cell activation and degranulation. The alpha-chain of Fc epsilon RI constitutes the Ig-binding subunit of this heterotetrameric receptor, and is itself a member of the Ig gene superfamily. We have isolated a human genomic DNA clone containing the entire Fc epsilon RI alpha gene, and completely sequenced a region from 1257 bp 5' of the transcription start site, to 513 bp 3' of the last exon of the gene. As with the previously characterized rat and mouse genes, human Fc epsilon RI alpha consists of five exons and four introns, and spans 5889 bp of genomic DNA. The splice donor and acceptor sites deduced by comparison with the cDNA sequence corresponded exactly to the locations found in analogous rodent genes. By mapping the 5' end of Fc epsilon RI alpha transcripts we found three major transcription initiation sites 24, 27, and 29 bp upstream of the ATG translation initiation codon. As well, several longer minor transcripts were seen, with a maximum of 60 nt of 5'-untranslated sequence. About 650 bp of DNA upstream of the ATG translation initiation codon were compared among human, rat, and mouse Fc epsilon RI alpha sequences in search of common motifs that might mediate conserved regulatory interactions with DNA binding proteins. A 172-bp region of the human Fc epsilon RI alpha 5'-flanking sequence was highly conserved in both rodent species. Further studies will be required to determine whether these or other sequences are involved in Fc epsilon RI alpha gene regulation.
Structure of the gene for the F allele of complement receptor type 1 and sequence of the coding region unique to the S allele.
Authors: Vik D P , Wong W W 
Published: January 2023

Abstract
The genes for human complement receptor type 1 (CR1) F and S alleles have been cloned and span a region of 133-160 kb on chromosome 1. The F allele was found to comprise 39 exons and the S allele contains an additional 8 exons. The leader sequence and 5'-untranslated region are contained in one exon. Each of the long homologous repeats (LHR), which contain seven short consensus repeats (SCR), is composed of 8 exons. Within a LHR, SCR 1, 5, and 7 are each encoded by a single exon, SCR 2 and 6 are each encoded by 2 exons, and a single exon codes for SCR 3 and 4. The transmembrane region is encoded by 2 exons and the cytoplasmic domain and the 3'-untranslated regions are coded for by separate exons. The sequences of the eight S allele-specific exons were very similar to those from LHR-A and -B, as was predicted by comparison of the genomic restriction maps. It had previously been suggested that the alleles of CR1 have arisen by a mechanism of unequal crossover. A comparison of intron sequences from LHR-A, -B, -C, and -S revealed data that support this hypothesis. The homologies of intron sequences from LHR-A, -B, and -C indicated that the crossover event between LHR-A and -C that gave rise to LHR-B probably occurred within the fourth exon of these LHR. Likewise, the crossover event between LHR-A and -B that produced LHR-S probably occurred within a 383 bp region around the sixth exon. Analysis of RNA from peripheral blood cells by the S1 nuclease assay indicated that the transcription start site is 111 bp upstream of the translation initiation codon ATG. The 5' rapid amplification of cDNA ends confirmed this position as a transcription start site and revealed another possible start site 29 bp further upstream.
cDNA cloning and expression of guinea pig neutrophil attractant protein-1 (NAP-1). NAP-1 is highly conserved in guinea pig.
Authors: Yoshimura T , Johnson D G 
Published: January 2023

Abstract
cDNA for neutrophil attractant protein-1 (NAP-1, also known as IL-8) was cloned from Con A-stimulated guinea pig spleen cells with human NAP-1 cDNA as a probe. Guinea pig NAP-1 cDNA is composed of 1433 bp with an open reading frame which encodes for a 101-amino-acid protein. Guinea pig NAP-1 had 70% amino acid sequence similarity to human NAP-1, which was much higher than a similarity between human and guinea pig monocyte chemoattractant protein-1 (MCP-1) (56%). Nucleotide sequence similarity within the coding region was 75%. To confirm its biological activity in guinea pig, recombinant guinea pig NAP-1 was expressed in COS-7 cells then purified. N-terminal sequence analysis gave two different N-termini at position 23 (Met) or 24 (Val). The two proteins showed their peak activity for guinea pig neutrophils at the concentration of 1 microgram/ml (10-7 M). Despite its high similarity to human NAP-1, the responsiveness of human neutrophils to guinea pig NAP-1 was minimum. Recombinant guinea pig NAP-1 caused strong neutrophil infiltration after intradermal injection into guinea pig skin. Since guinea pig is classified as a rodent, it was of interest to know whether human NAP-1 cDNA hybridizes to genomic DNA of other rodents such as mouse or rat, in which a NAP-1 homologue has not been found. Under low stringency conditions, human NAP-1 cDNA hybridized to human, rabbit, and guinea pig DNA, but not to mouse or rat DNA. Unlike NAP-1, human MCP-1 cDNA hybridized to genomic DNA of rabbit, guinea pig, mouse, and rat; MCP-1 cDNA have been cloned from these species. The apparent absence of a NAP-1 gene in mouse or rat makes this chemoattractant unique among the members of the protein family to which NAP-1 and MCP-1 belong.
In vitro candidastatic properties of the human neutrophil calprotectin complex.
Authors: Murthy A R , Lehrer R I , Harwig S S , Miyasaki K T 
Published: January 2023

Abstract
Microbiostatic mechanisms may contribute substantially to host defense against infection by certain microbes. We studied the candidastatic activity of human neutrophils, neutrophil cytosol, and neutrophil-derived "calprotectin," a cytosolic protein complex comprised of two subunits, MRP8 and MRP14. Intact neutrophils, neutrophil lysates (prepared by ultrasonic disruption, freezing and thawing, or nonionic detergent extraction), and granule-depleted neutrophil cytosol were effective in restricting the growth of Candida albicans in a nutrient-rich tissue culture medium, RPMI 1640. Neither a subcellular fraction enriched in neutrophil granules nor selected purified granule components (lactoferrin, myeloperoxidase, cathepsin G, leukocyte elastase, lysozyme, and defensins) exerted candidastatic activity in this medium. Gel filtration liquid chromatography, anion exchange FPLC, and SDS-PAGE showed that the fungistatic factor in neutrophil cytosol was associated with the calprotectin complex. Its antifungal effects included restriction of yeast phase and mycelial growth and inhibition of glucose incorporation by yeast phase cultures. The antifungal effects of calprotectin were sustained for over 120 h and were inhibited by zinc. However, studies with 65Zn-enriched RPMI suggested that the candidastatic effects of calprotectin were not mediated by sequestration or binding of zinc. After reversed phase HPLC, calprotectin fractions containing MRP14 exhibited fungistatic activity, whereas fractions depleted of MRP14 but enriched for MRP8 lacked fungistatic activity. The results support a potentially significant role for the calprotectin complex of neutrophil cytosol in antifungal defense and suggest that MRP14 is of key importance in that activity.
Shared T cell-defined antigens on independently derived tumors.
Authors: Sahasrabudhe D M , Burstyn D , Dusel J C , Hibner B L , Collins J L , Zauderer M 
Published: January 2023

Abstract
We report that a subset of tumors independently derived from a cloned line of contact-inhibited, non-tumorigenic murine fetal fibroblasts confer cross-protective immunity against each other in vivo. Concordant with the in vivo cross-protection, cytolytic T cell clones from mice immunized with one of these tumor lines specifically lyse the three other lines in the same set but do not cross-react with either the nontumorigenic parental line or another similarly derived tumor line representing a different antigenic profile. This and other recent evidence for shared expression of tumor rejection Ag contrasts with the antigenic diversity previously described for chemical- and radiation-induced tumors. In the interpretation of such data it is essential to distinguish between Ag expressed in association with the transformation process and Ag induced by random mutation of already transformed cells.
Neutrophils roll on E-selectin.
Authors: Lawrence M B , Springer T A 
Published: January 2023

Abstract
Using flow conditions that simulate those in post capillary venules, we have found that neutrophils attach and roll on a substrate bearing purified E-selectin. E-selectin resembles P-selectin (CD62) with regard to the dependence of attachment efficiency on wall shear stress and selectin density. In contrast, once attached, neutrophils form rolling adhesions on E-selectin that are much stronger than those on P-selectin. Rolling velocities on E-selectin are slower and have less variance than on P-selectin. With increasing shear stress, rolling velocities reach a plateau level that is dependent on E-selectin density, suggesting that the number of receptor-ligand bonds and the bond dissociation rate limit rolling velocity, and that the bonds are not broken by the applied force.
Induction by chemokines of lipid mediator synthesis in granulocyte-macrophage colony-stimulating factor-treated human neutrophils.
Authors: McDonald P P , Pouliot M , Borgeat P , McColl S R 
Published: January 2023

Abstract
In recent years, there has been a growing body of evidence suggesting that IL-8 and granulocyte-macrophage CSF (GM-CSF) play an important role in inflammatory processes. We show that after GM-CSF treatment, the exposure of human neutrophils to IL-8 results in the synthesis of leukotriene (LT)B4 and platelet-activating factor. In GM-CSF-treated cells, IL-8 induced a concentration-dependent synthesis of both lipid mediators, with a threshold at 10 to 30 nM, suggesting that IL-8 could stimulate phospholipase A2 activity, an enzyme essential for both syntheses. Accordingly, IL-8 induced a substantial release of 3H-arachidonic acid in GM-CSF-treated PMN. It was also found that IL-8 activates the neutrophil 5-lipoxygenase (5-LO), the other key enzyme in LT biosynthesis. IL-8 induced 5-LO activation in a time- and concentration-dependent manner, with a threshold at 1 nM, and prior treatment of neutrophils with GM-CSF enhanced this effect of IL-8 over the 1 to 300 nM range. Neutrophil-activating peptide-2 and the melanoma growth-stimulatory activity, two peptides that are closely related to IL-8, also had the ability to activate the 5-LO and stimulate LT synthesis, albeit less potently than IL-8. Finally, pertussis toxin and the 5-LO translocation inhibitor, MK-886, both blocked the IL-8-elicited 5-LO activation. Taken together, our results raise the possibility that the combined presence of IL-8 and of GM-CSF at inflammatory foci could result in the synthesis of platelet-activating factor and LTB4 by neutrophils, thereby contributing to the amplification of the inflammatory response.
Expression of alpha-3, alpha-5, and beta-4 neuronal acetylcholine receptor subunit transcripts in normal and myasthenia gravis thymus. Identification of thymocytes expressing the alpha-3 transcripts.
Authors: Mihovilovic M , Roses A D 
Published: January 2023

Abstract
We used amplification of reverse transcribed RNA to investigate the thymic transcription of genes encoding for subunits of neuronal acetylcholine receptors (AcChR). All thymic tissues investigated, which include normal thymi, myasthenic hypertrophic thymi, and both myasthenic and nonmyasthenic thymomas, express transcripts encoding for the alpha-3, the alpha-5, and the beta-4 subunits of AcChR. The thymic transcription of at least three different genes encoding for neuronal AcChR subunits suggests there is expression of neuronal AcChR in thymus. Amplification of reverse transcribed RNA and Northern blotting of thymic and peripheral immunocytes showed that thymocytes but not peripheral lymphocytes express alpha-3 AcChR subunit transcripts. This finding suggests that within the T cell lineage there is transcriptional regulation of the alpha-3 AcChR gene.
Characterization of dermal dendritic cells obtained from normal human skin reveals phenotypic and functionally distinctive subsets.
Authors: Nestle F O , Zheng X G , Thompson C B , Turka L A , Nickoloff B J 
Published: January 2023

Abstract
The relative contribution of dermal-derived immunocompetent cells to the overall immunologic response in skin has been hampered by the lack of appropriate isolation techniques. In this report, we provide a purification schema that reliably yields highly purified populations of dermal dendritic cells (DDC). These cells are motile, express high levels of class II MHC antigens that decorate their cytoplasmic dendritic processes, and lack numerous B cell, T cell, and natural killer cell antigens. Using a broad panel of 45 different antibodies, an extensive phenotypic analysis was completed, revealing distinctive profiles for subsets of DDC. Despite homogeneous light scatter profile and cytologic appearance, three subsets of DDC could be distinguished by phenotypic and functional criteria. All DDC, but not epidermal Langerhans cells, express factor XIIIa. By triple color cell staining the relative distribution of factor XIIIa positive DDC is as follows: subset 1, 65% to 70% of total DDC express neither CD1a nor CD14; subset 2, 15% to 20% of total DDC express CD1a but not CD14; and subset 3, 10% to 15% of total DDC express CD14 but not CD1a. The CD14-negative subset of DDC were shown to be as potent stimulators of allogeneic mixed lymphocyte reactions as Langerhans cells or blood-derived dendritic cells. However, DDC subsets differed in their ability to support autologous T cell proliferation in response to the mitogenic lectin PHA or bacterial-derived superantigen. In these assays, subsets 1 and 2 were significantly more potent as antigen-presenting cells compared with subset 3. Thus, normal skin contains at least three separate populations of DDC, which have distinctive phenotypic markers and immunologic capabilities.
Targeting of T lymphocytes to Neu/HER2-expressing cells using chimeric single chain Fv receptors.
Authors: Stancovski I , Schindler D G , Waks T , Yarden Y , Sela M , Eshhar Z 
Published: January 2023

Abstract
Cell surface molecules essential for the transformed phenotype or growth of malignant cells are attractive targets for anticancer immunotherapy. Antibodies specific to Neu/HER2, a human adenocarcinoma-associated growth factor receptor, were demonstrated to have tumor-inhibitory capacity. Yet, the inefficient accessibility of antibodies to solid tumors limits their clinical use. To redirect effector lymphocytes to adenocarcinomas, we constructed and functionally expressed in T cells chimeric single chain receptor genes incorporating both the Ag-binding domain of anti-Neu/HER2 antibodies and the zeta-signal-transducing subunit of the TCR/CD3 complex or the gamma-signal-transducing subunit of the Ig Fc receptor complex. Surface expression of the anti-Neu/HER2 chimeric genes in cytotoxic T cell hybridomas endowed them with specific Neu/HER2 recognition enabling their activation for IL-2 production and lysis of transformed cells overexpressing Neu/HER2. These chimeric genes hold promise for the immunotherapy of cancer.
Multiple neutralizing B-cell epitopes of human T-cell leukemia virus type 1 (HTLV-1) identified by human monoclonal antibodies. A basis for the design of an HTLV-1 peptide vaccine.
Authors: Baba E , Nakamura M , Tanaka Y , Kuroki M , Itoyama Y , Nakano S , Niho Y 
Published: January 2023

Abstract
We have generated 153 human mAb reacting with natural envelope glycoprotein-gp46 of human T-cell leukemia virus type-1 (HTLV-1) by the EBV-transformation of B lymphocytes obtained from patients with HTLV-1-associated myelopathy (HAM)/Tropical spastic paraparesis (TSP). Twenty-four of these mAb had neutralizing activity of HTLV-1 as determined by an HTLV-1-induced syncytium formation inhibition assay in vitro. The reactivity of these neutralizing mAb was studied by using 9 different synthetic peptides covering immunodominant regions of the gp46. Thirteen out of these 24 neutralizing mAb reacted with gp46 peptide 175-199, whereas one mAb reacted with gp46 213-236 and another one with gp46 288-317. The other 9 neutralizing mAb did not react with any of these peptides. Fine epitope mapping of the mAb reacting with gp46 peptide 175-199 revealed the presence of 4 distinct neutralizing B-cell epitopes on this region; (1)187-193, (2)191-196, (3)193-199, and (4) continuous conformational B-cell epitope. The competitive antibody-binding inhibition experiments by soluble phase synthetic peptides showed that the binding activity of these neutralizing mAb to the corresponding synthetic peptides is equal to or a little lower than that to native gp46 protein, suggesting that synthetic peptides can form structure very similar to the neutralizing epitopes on native gp46 protein. The present study is the first systematic demonstration of multiple neutralizing B-cell epitopes of HTLV-1 in human HTLV-1 infection. It would be possible to prepare a synthetic peptide vaccine against HTLV-1 based on these newly identified multiple linear neutralizing B-cell epitopes of HTLV-1.
Studies on the mechanisms by which transforming growth factor-beta (TGF-beta) protects against allergic encephalomyelitis. Antagonism between TGF-beta and tumor necrosis factor.
Authors: Santambrogio L , Hochwald G M , Saxena B , Leu C H , Martz J E , Carlino J A , Ruddle N H , Palladino M A , Gold L I , Thorbecke G J 
Published: January 2023

Abstract
Experimental allergic encephalomyelitis (EAE) is an autoimmune disease in which peripheral lymphoid cells are activated by immunization with myelin proteins and become effector cells that traverse the central nervous system (CNS) capillaries and initiate inflammatory demyelinating lesions. The administration of transforming growth factor-beta (TGF-beta) has been shown previously to decrease the incidence and severity of EAE. In our studies we have determined: 1) the effects of TGF-beta injected at different intervals after the EAE-inducing immunization; 2) the effect of TGF-beta on the development of sensitized T cells, as assayed by the proliferative responses of T cells from lymph nodes and peripheral blood; 3) the extent of lymphoid cell infiltration in CNS of TGF-beta-treated and control mice; and 4) the role of endogenous TGF-beta and TNF in determining the severity of both acute and relapsing EAE. The onset of acute-EAE in SJL mice, induced by immunization with spinal cord homogenate in CFA and pertussigen, is on days 10 to 15. Although daily i.p. injections of 0.2 to 2 micrograms TGF-beta 1 or TGF-beta 2 on days 5 to 9 after immunization are highly protective, injections on days 1 to 5 or 9 to 13 are not. Moreover, anti-TGF-beta accelerates and aggrevates EAE when given on days 5 and 9, but not on day 12. Anti-TNF, injected on days 5 and 9, provides a comparable degree of protection as does TGF-beta. Similarly, in relapsing EAE, anti-TGF-beta increases, whereas anti-TNF decreases the incidence and severity of relapses. TGF-beta treatment on days 5 to 9 does not influence the appearance of sensitized cells in peripheral blood and lymph nodes, but does prevent the accumulation of T cells in brain and spinal cord, as assayed on days 15 to 20. It is concluded that the protective effect of TGF-beta is exerted at the level of the target organ, CNS and/or its vascular endothelium, rather than through a direct effect on lymphoid cells, and that there is a small window of 4 days in which TGF-beta exerts its protective effect.