bluuebunny/crossref_metadata_2025_split huggingface dataset:
Appearance of TCR-alpha beta+ CD4-CD8- skin intraepithelial lymphocytes in radiation bone marrow chimeras.
Authors: Ogimoto M , Matsuzaki G , Yoshikai Y , Tauchi Y , Nomoto K 
Published: December 2022

Abstract
Thymocytes expressing homogeneous TCR V gamma 5/V delta 1 gene without N nucleotide addition (canonical sequence) have been reported to be positively selected in fetal thymus. Because skin intraepithelial lymphocytes (s-IEL) also express canonical sequence, it is proposed that s-IEL are generated by an epidermis-specific homing of these positive selected fetal V gamma 5/V delta 1-bearing thymocytes. We have reported that positive selection of V gamma 5+ thymocytes is not seen in AKR/J--&gt;C3H/He bone marrow chimeras. In this report, we analyzed the phenotype of donor-derived s-IEL from AKR/J--&gt;C3H/He bone marrow chimeras that appeared in the absence of positive selection of V gamma 5-bearing thymocytes. We found interestingly that almost all donor-derived s-IEL in the bone marrow chimeras expressed TCR-alpha beta lack expression of both CD4 and CD8. Furthermore, TCR-alpha beta+ s-IEL were detected in adult-thymectomized bone marrow chimeras, indicating that the TCR-alpha beta+ s-IEL are extrathymically derived. All these results suggest that the s-IEL expressing TCR-alpha beta appear extrathymically in the absence of positive selection of V gamma 5/V delta 1-bearing thymocytes. Our results may also explain the contradicting result between human s-IEL, which are TCR-alpha beta+ CD4- CD8- and murine s-IEL, and suggest the importance of extrathymic T cell differentiation pathway of the TCR-alpha beta lineage in immune surveillance.
Monoclonal c-myc transformed macrophage cell lines. I. Heterogeneity in ability to process and present antigen.
Authors: Trannoy E , Manser T , Cole M D , Daley M J 
Published: December 2022

Abstract
Processing of proteins into immunogenic forms and their subsequent presentation to T cells are mediated by APC. Monocytes and macrophages have long been recognized as one of the APC types. However, little is known about whether functional heterogeneity in processing and presentation exist within the monocyte/macrophage population. Past difficulties in obtaining clonal representatives of these populations have limited investigations in this regard. The c-myc-containing retrovirus MRV, previously shown to immortalize murine macrophages, was used to generate a large panel of macrophage cell clones. Differences observed in cell surface antigen expression and morphology demonstrated phenotypic heterogeneity among these clones. Functional heterogeneity was also observed both before and after IFN-gamma and IL-4 stimulation. The clones differ in their capacity to present several nominal antigens to T cell hybridomas. When parallel variation in ability to present both a nominal antigen and a peptide representing the epitope for which a T cell hybridoma was specific was observed among the clones, this variation correlated with the levels of surface MHC class II antigen the clones expressed. In contrast, diversity in the ability to process and present certain nominal antigens among clones that all presented the corresponding antigenic peptide with similar efficiency did not appear to be due to differences in levels of surface MHC class II molecules. Our results suggest that the macrophage clones are heterogeneous in their ability to both process and present several antigens. The ability to obtain macrophage tissue culture cell lines displaying phenotypic and functional heterogeneity should allow insight into the impact of normal macrophage heterogeneity on the outcome of immune responses in vivo.
Characterization and expression of recombination activating genes (RAG-1 and RAG-2) in Xenopus laevis.
Authors: Greenhalgh P , Olesen C E , Steiner L A 
Published: December 2022

Abstract
The primary repertoire of B and T cells is established by V(D)J recombination. Two closely linked genes, RAG-1 and RAG-2, are essential for this process, and have been identified in mice, humans, and chickens. To study lymphocyte development in Xenopus laevis, we have characterized RAG-1 and RAG-2 in this species and examined their patterns of expression. Degenerate oligonucleotides, based on the known highly conserved RAG-1 sequences, were used to amplify, by the polymerase chain reaction, a segment of Xenopus RAG-1 from genomic DNA. A product of expected size was obtained and used to identify a genomic clone that contained the complete coding region of RAG-1 (1045 codons), and approximately the 3'-half of the coding region of RAG-2. The coding regions of RAG-1 and RAG-2 each lie on a single exon, are in opposite transcriptional orientation, and are separated by approximately 6 kb. The sequence of the remainder of RAG-2 was determined by PCR amplification of genomic DNA, with primers based on sequence analysis of RAG-2 cDNA clones. The predicted Xenopus RAG-1 protein is 71% identical in amino acid sequence to the sequences of each of the mouse, human, and chicken proteins; from position 392 to 1012 the identity is 88%. The coding region of Xenopus RAG-2 (520 codons) is somewhat less conserved among the different species. Tissue-specific expression of Xenopus RAG-1 and RAG-2 was examined both by Northern blotting and by a reverse transcription-polymerase chain reaction assay. In juvenile frogs, the highest levels of RAG-1 and RAG-2 expression were observed in the thymus, with lower levels in liver and spleen, and even lower levels in the kidneys. In adults, the thymus and bone marrow were found to be the principal sites of expression of both genes. RAG-2, but not RAG-1, was expressed in oocytes.
Resolution of blood-stage malarial infections in CD8+ cell-deficient beta 2-m0/0 mice.
Authors: van der Heyde H C , Manning D D , Roopenian D C , Weidanz W P 
Published: December 2022

Abstract
We utilized a definitive model of CD8+ T cell deficiency, the beta 2-microglobulin-deficient (beta 2-m0/0) mouse, to determine whether CD8+ T cells are required in the resolution of blood-stage malaria. In a parallel experiment, C57Bl/6 mice treated with anti-CD8 mAb showed significantly higher levels of parasitemia than untreated C57Bl/6 control mice at several points during the infection. This finding suggests some role for CD8+ cells in containing malaria. However, the beta 2-m0/0 mice, which are genetically blocked from expressing MHC class I or class Ib glycoproteins and therefore have &lt; 2.5% of the normal number of CD8+ T cells, nevertheless resolved infections with three virulence variants of murine Plasmodium. The resolution of Plasmodium chabaudi adami, Plasmodium yoelii yoelii 17X, and Plasmodium chabaudi chabaudi AS infections by beta 2-m0/0 mice in the virtual absence of CD8+ cells demonstrates that these cells are not required to suppress murine malaria and that the suppression mechanism is not MHC class I restricted. The similarity of the time-course for resolution of infection in beta 2-m0/0 and intact control mice with all three subspecies of Plasmodium further supports the lack of a requirement for CD8+ T cells in the suppression of malarial parasitemia.
Role of IL-10 on antigen-presenting cell function for schistosomal egg-specific monoclonal T helper cell responses in vitro and in vivo.
Authors: Flores Villanueva P O , Chikunguwo S M , Harris T S , Stadecker M J 
Published: December 2022

Abstract
Egg Ag-stimulated lymphoid cell culture supernatants from schistosome-infected mice significantly inhibited Ag-specific, MHC-restricted proliferative responses of cloned schistosomal egg Ag-specific CD4+, Th-1-type lymphocytes. The inhibitory molecule in the supernatants was found to be the cytokine IL-10. Maximal IL-10 was produced by cells from mice carrying 8-wk schistosome infections, and none by cells from normal mice. IL-10 exerted its biologic activity on APC, and not directly on the cloned lymphocytes, resulting in the inhibition of Th-1 lymphocyte proliferation, whereas Th-2 responses were not affected. Most significantly, IL-10 also affected Th-1 clone activity in vivo, as measured by the inhibition of schistosomal egg Ag-specific local delayed-type hypersensitivity reactions. IL-10 produced in schistosome-infected individuals may play a role in the generation of APC, such as macrophages in schistosomal egg granulomas, unable to efficiently stimulate, but capable of inducing a state of anergy/unresponsiveness in Th-1 lymphocytes. We believe that this state of Th-1 cell anergy translates into the down-regulation of granulomatous hypersensitivity (immunomodulation) characteristically observed in the evolving schistosomal disease.
Antibodies chaperone circulating IL-6. Paradoxical effects of anti-IL-6 "neutralizing" antibodies in vivo.
Authors: May L T , Neta R , Moldawer L L , Kenney J S , Patel K , Sehgal P B 
Published: December 2022

Abstract
In the baboon or the mouse, a stimulus such as LPS, TNF, or IL-1 typically led to a rapid induction of circulating IL-6, the levels peaked by 2 to 3 h and then declined to near-baseline values by 6 to 8 h. Administration to baboons or mice of "neutralizing" anti-IL-6 mAb followed by an IL-6 inducer led to a marked and sustained increase in circulating IL-6 levels. IL-6 Ag, IL-6 biologic activity, neutralizing anti-IL-6 mAb, and IL-6/anti-IL-6-mAb complexes could all be observed for an extended period of time (beyond 8 h) in the circulation of such animals. Nevertheless, in mice, if the anti-IL-6 mAb had been administered before the IL-6 inducer, there was a reduction in the in vivo IL-6-induced stimulation of fibrinogen levels, indicating that most of the intravascular IL-6 was not readily available for eliciting hepatocyte effects under these experimental conditions. Intraperitoneal administration into mice of mixtures of murine rIL-6 or human rIL-6 together with their respective anti-IL-6 mAb led to a marked increase in the appearance and longevity in the peripheral circulation of the exogenously administered murine or human rIL-6 species in a biologically active form. Varying the ratio of human rIL-6 to anti-human IL-6 mAb indicated that a molar ratio of 1:1 was sufficient for the ability of mAb to chaperone IL-6 in the murine circulation. Human rIL-6 mixed with "neutralizing" mAb in the approximate ratio 1:1 elicited an enhanced fibrinogen response in vivo in the mouse; an IL-6:mAb ratio of 1:125 led to a reduction in the fibrinogen response even though the levels of circulating B9 bioactivity and of human rIL-6-Ag were maximal under these conditions. Gel-filtration chromatographic and Western blotting analyses of IL-6 present in vivo in the mAb-free baboon revealed that although the IL-6 Ag was largely present in high molecular mass complexes of size 400 kDa in association with soluble IL-6 receptor, the B9 bioactivity was largely of low molecular mass (20 kDa). In contrast, in the anti-IL-6 mAb-treated baboon or mouse, the IL-6 Ag and bioactivity were both largely in complexes of 200 kDa. Thus, the binding of IL-6 in the intravascular compartment to other proteins, anti-IL-6 mAb in the present studies, gives IL-6 unexpected biochemical and pharmacologic properties in vivo.
Immobilization of Fc epsilon receptors by wheat germ agglutinin. Receptor dynamics in IgE-mediated signal transduction.
Authors: McCloskey M A 
Published: December 2022

Abstract
Transmembrane signaling initiated by the receptor with high affinity for Fc stem of IgE(Fc epsilon RI) requires the diffusion-dependent cross-linkage and persistent aggregation of the Fc epsilon RI. Disruption or prevention of receptor cross-links at any time during the secretory response quickly terminates secretion. We found that in the rat basophilic leukemia mast cell line, addition of wheat germ agglutinin, a lectin that binds to the Fc epsilon RI alpha subunit, caused a precipitous decline in the lateral diffusional and electrokinetic mobilities of the Fc epsilon RI. Both the unoccupied Fc epsilon RI and IgE-Fc epsilon RI complexes became immobilized, as determined from in situ electromigration and postelectric field relaxation. Immobilization of the Fc epsilon RI by wheat germ agglutinin was accompanied by a ligand-reversible association of 125I-IgE-Fc epsilon RI complexes with the Triton X-100-insoluble cytoskeletal fraction. Wheat germ agglutinin rapidly inhibited Fc epsilon RI-mediated signal transduction and secretion, whether cross-linkage was initiated by multivalent antigen, covalent IgE oligomers, anti-IgE, or anti-Fc epsilon RI antibody. Inhibition of signaling and secretion occurred on simultaneous addition of wheat germ agglutinin and antigen, and also when wheat germ agglutinin was added at increasing times after induction of Fc epsilon RI cross-linkage. Wheat germ agglutinin neither reduced the affinity of anti-DNP IgE for haptenic DNP-lysine nor reversed the binding of IgE to the Fc epsilon RI. Although wheat germ agglutinin caused internalization of the Fc epsilon RI, the onset of inhibition preceded and its extent exceeded that of internalization. Wheat germ agglutinin did not interfere with the secretory apparatus, as indicated by its lack of inhibition of secretion elicited by calcium ionophores. These findings suggest that inhibition of signal transduction is secondary to an initial event linked to immobilization of the Fc epsilon RI. Implications of these results are discussed with respect to the dynamics of Fc epsilon RI aggregation on rat basophilic leukemia cells.
L- and E-selectin can recognize the same naturally occurring ligands on high endothelial venules.
Authors: Mebius R E , Watson S R 
Published: December 2022

Abstract
The selectin family of cell adhesion molecules consists of three members, E-selectin (ELAM-1), L-selectin (LECAM-1), and P-selectin (CD62, GMP140, or PADGEM), which are all involved in binding of leukocytes to endothelial cells. All members have structural similarities and they can all bind to a common carbohydrate epitope, sialyl Lewis X in in vitro assays. To study cross-reactivity of the selectins in more detail we used Ig chimeras of murine and human L- and human E-selectin. All three chimeras bound to the natural ligands of L-selectin on specialized high endothelial venules in both human and murine lymphoid organs as determined by immunohistochemistry and were able to precipitate 50- and 90-kDa sulfated ligands from organ cultures of murine peripheral and mesenteric lymph nodes. This recognition was calcium dependent and inhibitable by mAb specific for the lectin domain of the respective selectin. L- and E-selectin binding to high endothelial venules and to the sulfated ligands was inhibitable by the carbohydrates, fucoidan and sialyl Lewis X, respectively. Although immunoprecipitations showed that both murine and human L-selectin could recognize the sulfated ligands from high endothelial venules more efficiently than human E-selectin at the concentrations used, both L- and E-selectin chimeras could inhibit in vivo lymphocyte trafficking into peripheral lymph nodes equally well.
Induction of a macrophage-like nitric oxide synthase in cultured rat aortic endothelial cells. IL-1 beta-mediated induction regulated by tumor necrosis factor-alpha and IFN-gamma.
Authors: Suschek C , Rothe H , Fehsel K , Enczmann J , Kolb-Bachofen V 
Published: December 2022

Abstract
We investigated the effects of murine rTNF-alpha, human rIL-1 beta, and rat rIFN-gamma in various concentrations and/or combinations on inducible nitric oxide (NO) production in primary cultures of rat aortic endothelial cells. Northern blot analysis of total RNA from induced and control cultures using the cloned mouse macrophage gene of inducible NO synthase as probe as well as polymerase chain reaction using a specific primer sequence gave a positive signal for activated cells only. A RNA approximately 4.4 kb of length similar to the inducible form of NO synthase in macrophages was labeled. The concentration of nitrite as a stable reaction product of NO in culture supernatants was determined 24 h after incubation with the various cytokines. IL-1 beta alone (40 to 1000 U/ml) induced formation of increasing amounts of nitrite with increasing concentrations of IL-1 beta present. Neither TNF-alpha alone (10 to 2000 U/ml) nor IFN-gamma alone 25 to 500 U/ml) showed significant effects on nitrite production. Simultaneous incubation with low concentrations of TNF-alpha (&lt; or = 100 U/ml) and IL-1 beta abrogated the induction effect of IL-1 beta. Conversely, addition of high concentrations of TNF-alpha (&gt; or = 500 U/ml) led to near maximal levels of nitrite formation even at lowest IL-1 beta concentrations (40 U/ml). In addition, simultaneous incubation of endothelial cells with IFN-gamma plus IL-1 beta and/or TNF-alpha led to near maximal NO production of endothelial cells, even at lowest IFN-gamma concentrations (25 U/ml). We hypothesize that the regulating effect of TNF-alpha may in vivo help to prevent local inflammatory responses from spreading to intact sites.
Altered prostaglandin E2 regulation of cytokine production in atopic dermatitis.
Authors: Chan S C , Kim J W , Henderson W R , Hanifin J M 
Published: December 2022

Abstract
The monocyte-derived inflammatory mediator, prostaglandin E2 (PGE2), can reduce IFN-gamma production, and this in turn may relate to IL-4 up-regulation of IgE synthesis and impaired delayed hypersensitivity in atopy. These abnormalities may relate to the cyclic nucleotide dysregulation in atopic dermatitis (AD), where monocyte cyclic AMP-phosphodiesterase (PDE) activity is increased and the consequent reduction in cAMP levels allows increased inflammatory responsiveness. In this study, we assessed the relationship between PGE2 and IFN-gamma production along with abnormal PDE activity in AD monocytes. Blood mononuclear leukocytes (MNL) from normal and AD donors were cultured for 24 hours, and supernatants were assayed for PGE2 and IFN-gamma by RIA. Spontaneous PGE2, but not leukotriene C4 release, was significantly increased in AD MNL (p &lt; 0.05), although IFN-gamma levels were reduced (p &lt; 0.05). In contrast, purified AD T cells, after removal of PGE2-producing monocytes, produced levels of IFN-gamma significantly higher than in normal T cell cultures. Inhibition of PGE2 synthesis by indomethacin caused increased IFN-gamma production by MNL cultures. We noted a strong negative correlation (r = 0.77) between PDE activity and IFN-gamma production in MNL cultures. We speculate that abnormal cyclic nucleotide metabolism caused by increased PDE activity may allow elevated levels of PGE2 production by AD monocytes. This study demonstrates a regulatory interaction between monocytes and T cells in AD and suggests that PGE2 may be an extracellular messenger between these cells to modulate IFN-gamma production.
Increased sensitivity to TNF-mediated cytotoxicity of BL6 melanoma cells after H-2Kb gene transfection.
Authors: Kim M , Herberman R , Gorelik E 
Published: December 2022

Abstract
Transfection of the H-2Kb and neor genes into BL6-8 (H-2Kb-, H-2Db+) melanoma clone resulted in various phenotypic changes with appearance of soybean agglutinin (SBA) and Grifonia Simplicifolia 1-B4 (GS1B4) lectin binding carbohydrates and loss of melanoma-associated antigen (MAA). In parallel H-2Kb gene-transfected melanoma cells showed increased sensitivity to TNF lysis. To further delineate the ability of H-2Kb gene to induce the phenotypic changes and TNF sensitivity, BL6-8 melanoma clone was transfected with the H-2Kb gene alone without cotransfection with neor gene and transfected cells were selected for adherence to SBA lectin-conjugated agarose beads. Analysis of isolated clones revealed that 38 of 47 tested clones have been found to be expressing the H-2Kb Ag, SBA, and GS1B4 lectin binding carbohydrates but lost MAA, e.g., H-2Kb+, lectin+, MAA-, and in parallel these cells became sensitive to TNF lysis. Although all clones with high expression of H-2Kb Ag were sensitive to TNF lysis, it seems unlikely that H-2K molecules are directly required for or involved in TNF-induced melanoma cell lysis. This conclusion is based on findings that four H-2Kb-transfected clones selected on SBA-agarose beads did not expressed H-2Kb Ag but manifested increase in SBA and GS1B4 lectin binding and loss of MAA and also became sensitive to TNF lysis. It seems that increase in TNF sensitivity is a part of the broad phenotypic changes induced by the H-2K gene that remained stable even in the clones in which the transfected H-2Kb gene was lost or down-regulated. We believe that the effects of the H-2Kb gene on melanoma cell phenotype and TNF sensitivity are indirect and are probably mediated via its inhibition of the melanoma-associated ecotropic retrovirus production and activation of some repressed cellular genes. Study of the mechanisms responsible for TNF sensitivity of BL6 melanoma cells revealed that the H-2Kb gene transfection resulted in an increase in p55 TNF receptor expression. TNF-induced activation of phospholipase A2 and release of arachidonic acid metabolites was observed only in the H-2Kb transfected, but not in BL6-8 melanoma cells transfected with neor or class II H-21Ak genes. TNF resistance of BL6 melanoma cells appeared to be due to a block in transduction of the lytic signal that was reversed after transfection with H-2Kb gene.
Pathway of signal delivery to murine thymocytes triggered by co-crosslinking CD3 and Thy-1 for cellular DNA fragmentation and growth inhibition.
Authors: Nakashima I , Pu M Y , Hamaguchi M , Iwamoto T , Rahman S M , Zhang Y H , Kato M , Ohkusu K , Katano Y , Yoshida T 
Published: December 2022

Abstract
The signal delivery pathway triggered by crosslinking CD3 and Thy-1 together (CD3/Thy-1 crosslinkage) on murine thymocytes for cellular DNA fragmentation/growth inhibition was analyzed. The treatment of thymocytes with herbimycin A as a specific tyrosine kinase inhibitor under suboptimum conditions before the CD3/Thy-1 crosslinkage partially but preferentially inhibited the otherwise promoted tyrosine phosphorylation of p40 and p56. Evidence was then provided that acceleration of the kinase activity of p56lck was involved in the CD3/Thy-1 crosslinkage-triggered signal. Partial characterization of p40 distinguished it from the p43 and p41 MAP kinases, the tyrosine phosphorylation of which was only marginally accelerated. Promotion of DNA fragmentation by the CD3/Thy-1 crosslinkage-triggered signal was actually ablated by the treatment with herbimycin, suggesting the obligatory involvement of the herbimycin highly sensitive kinase activity in the signal pathway. The signal induced by co-crosslinkage of CD3 and Thy-1 was also shown to be negatively biased against mature T lymphocytes, suppressing their CD3-mediated growth response. The negative signal was then found to partially attack the process of c-fos transcription as an earlier nuclear event. Interestingly, this c-fos suppression was prevented by the treatment of thymocytes with herbimycin before stimulation, for accelerated expression of c-fos. It is suggested from these results that the CD3/Thy-1 crosslinkage delivers protein tyrosine kinase-dependent negative signaling for inhibition of early and late nuclear events of both immature thymocytes and mature T lymphocytes.