bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression Screening of a Yeast Artificial Chromosome Contig Refines the Location of the MouseH3aMinor Histocompatibility Antigen Gene
Authors: Zuberi Aamir R. , Christianson Gregory J. , Dave Sonal B. , Bradley Julie A. , Roopenian Derry C. 
Published: December 2022

AbstractThe H3 complex, on mouse Chromosome 2, is an important model locus for understanding mechanisms underlying non-self Ag recognition during tissue transplantation rejection between MHC-matched mouse strains. H3a is a minor histocompatibility Ag gene, located within H3, that encodes a polymorphic peptide alloantigen recognized by cytolytic T cells. Other genes within the complex include β2-microglobulin and H3b. A yeast artificial chromosome (YAC) contig is described that spans the interval between D2Mit444 and D2Mit17, a region known to contain H3a. This contig refines the position of many genes and anonymous loci. In addition, 23 new sequence-tagged sites are described that further increase the genetic resolution surrounding H3a. A novel assay was developed to determine the location of H3a within the contig. Representative YACs were modified by retrofitting with a mammalian selectable marker, and then introduced by spheroplast fusion into mouse L cells. YAC-containing L cells were screened for the expression of the YAC-encoded H3aa Ag by using them as targets in a cell-mediated lympholysis assay with H3aa-specific CTLs. A single YAC carrying H3a was identified. Based on the location of this YAC within the contig, many candidate genes can be eliminated. The data position H3a between Tyro3 and Epb4.2, in close proximity to Capn3. These studies illustrate how genetic and genomic information can be exploited toward identifying genes encoding not only histocompatibility Ags, but also any autoantigen recognized by T cells.
Stringent Allele/Epitope Requirements for MART-1/Melan A Immunodominance: Implications for Peptide-Based Immunotherapy
Authors: Bettinotti Maria P. , Kim Christina J. , Lee Kang-Hun , Roden Matthew , Cormier Janice N. , Panelli Monica , Parker Kenneth K. , Marincola Francesco M. 
Published: December 2022

AbstractThe exclusiveness of the relationship between peptide and HLA alleles, combined with their extensive polymorphism, emphasizes the need for immunization strategies based on endogenous processing of full length proteins (containing multiple epitopic determinants) for presentation to T cells. This could allow vaccination regardless of the patient’s HLA phenotype, assuming that individual molecules can be efficient T cell Ags in association with various HLA alleles. An endogenous system of Ag presentation was developed using dendritic cells infected with recombinant viral vectors expressing the melanoma-associated Ag MART-1/Melan A. CD8+ T cells from melanoma patients were activated in vitro by coincubation with infected dendritic cells and tested for recognition of HLA-A-matched melanoma targets. This allowed the analysis of T cell induction in association with any HLA-A allele of a given patient’s phenotype. In this system, MART-1/Melan A could not efficiently immunize in association with HLA-A alleles other than A*0201, including the one residue variant from A*0201: HLA-A*0226. Clonal analysis of MART-1/Melan A-specific CTL confirmed that MART-1/Melan A immunodominance is strongly restricted to the AAGIGILTV/HLA-A*0201 combination. The stringent epitope/allele requirements for MART-1/Melan A/TCR interactions were not associated with limitations in the TCR repertoire. In conclusion, autologous induction of MART-1/Melan A CTL by whole Ag processing and presentation is restricted to a unique allele/ligand combination and is excluded by minimal changes in HLA structure. Thus, whole protein vaccination for small m.w. Ags may provide no further advantage over a peptide-based approach.
T Cells Specific for a Polymorphic Segment of CD45 Induce Graft-Versus-Host Disease with Predominant Pulmonary Vasculitis
Authors: Chen Wei , Chatta Gurkamal S. , Rubin William D. , Clark Joan G. , Hackman Robert C. , Madtes David K. , Ligitt Denny H. , Kusunoki Yoichiro , Martin Paul J. , Cheever Martin A. 
Published: December 2022

AbstractTo study the character of graft-vs-host disease (GVHD) induced by T cells specific for hemopoietic cells, T cells specific for a polymorphic segment of CD45 were transferred into CD45 congenic mice. C57BL/6 mice that express the CD45b allele were immunized with a 13 mer peptide representing the polymorphic segment (p257–268) of CD45a protein. Conversely, C57BL/6 mice congenic for CD45a were immunized with the CD45b peptide. CD4+ T cells specific for allelic CD45 peptides were elicited. Importantly, T cells specific for CD45 peptides proliferated specifically and vigorously in response to spleen cells expressing the appropriate polymorphic CD45 protein. T cells specific for CD45 induced a substantial graft-vs-host response (GVHR) with predominant early pulmonary vasculitis and later more widespread interstitial mononuclear cell infiltration and alveolitis. No GVHR was induced in bone marrow chimeras expressing only donor hemopoietic cells. Thus, donor T cell recognition of host hemopoietic cells is sufficient to elicit GVHR, but the classical skin, liver, and gut manifestations of GVHD were not observed. The CD45-specific T cells used secreted Th1 cytokines, but without detectable soluble IL-2. Studies using CD45-specific T cells with different effector functions might allow further dissection of donor cell requirements for GVHD syndromes.
Phosphorylation of the Cytoplasmic Domain of E-Selectin Is Regulated During Leukocyte-Endothelial Adhesion
Authors: Yoshida Masayuki , Szente Brian E. , Kiely Jeanne-Marie , Rosenzweig Anthony , Gimbrone Michael A. 
Published: December 2022

AbstractE-selectin, a selectin expressed on activated vascular endothelium, supports rolling and stable adhesion of leukocytes at sites of inflammation. Previously, we have reported that leukocyte adhesion to cultured endothelial cells induces association of the cytoplasmic domain of E-selectin with cytoskeletal elements, suggesting that outside-in signaling may occur during E-selectin-mediated adhesion. To investigate this potential signaling function of E-selectin, HUVEC activated with recombinant human IL-1β (10 U/ml, 4 h) were labeled with [32P]orthophosphate, and E-selectin was immunoprecipitated using mAb H18/7. Autoradiography revealed constitutive phosphorylation of E-selectin in these cells and time-dependent dephosphorylation following adhesion of HL-60 cells. Cross-linking of cell surface E-selectin using H18/7 and a polyclonal secondary Ab induced E-selectin dephosphorylation, as did adhesion of beads coated with recombinant P-selectin glycoprotein ligand-1 (PSGL-1), an E-selectin ligand. Using adenoviral vector-mediated transfection in HUVEC of a tail-less E-selectin and phosphoamino acid analysis, we documented phosphorylation occurring exclusively within the cytoplasmic domain and involving serine residues. Additional experiments using a series of cytoplasmic domain mutants of E-selectin expressed in COS-7 cells localized the regions that were constitutively phosphorylated. Preincubation with okadaic acid and sodium vanadate abrogated adhesion-induced dephosphorylation of E-selectin. Thus, E-selectin, which is constitutively phosphorylated in cytokine-activated human endothelial cells, undergoes an enzymatically regulated dephosphorylation following leukocyte adhesion. This process appears to be triggered by multivalent ligand binding and/or cross-linking of cell surface E-selectin. Ligand-dependent regulation of the phosphorylation of E-selectin’s cytoplasmic domain provides additional evidence for a transmembrane signaling function of this molecule during leukocyte-endothelial interactions.
CD4+ T Cells Migrate into Inflamed Skin Only If They Express Ligands for E- and P-Selectin
Authors: Tietz Wolfgang , Allemand Yvonne , Borges Eric , von Laer Dorothea , Hallmann Ruppert , Vestweber Dietmar , Hamann Alf 
Published: December 2022

Abstract
Previous data suggested a role of endothelial selectins in skin homing of lymphocytes. In the current study, we have analyzed the expression and functional role of E-and P-selectin ligands on CD4+ T cells induced in vivo upon skin sensitization, using soluble selectin-Ig chimera and blocking Abs. Only low numbers of CD4+ cells expressing significant levels of E- or P-selectin ligands were present in s.c. lymph nodes of untreated mice (0.5–1.5% and 2–4%, respectively). Induction of a delayed-type hypersensitivity reaction increased the percentage of E-selectin-binding CD4+ cells in the draining lymph nodes up to 6 to 9% and that of P-selectin-binding cells up to 14%. The majority of E- and P-selectin-binding cells displayed an activated phenotype as judged by the increase in IL-2R, CD71, or cell size. The populations of E- and P-selectin-binding cells were largely overlapping; all E-selectin-binding cells also bound to P-selectin, whereas only a subfraction of P-selectin-binding cells reacted with E-selectin. Both E- and P-selectin-binding CD4+ cells, isolated by FACS, efficiently migrated into inflamed, but not normal skin, whereas P- or E-selectin ligand-negative CD4+ T cells did not. Abs against one of the two endothelial selectins partially inhibited the entry of isolated, ligand-positive cells, whereas a combination of Abs against both selectins almost completely abrogated skin homing. These data indicate that the expression of functional ligands for E- and for P-selectin is essential for homing of CD4+ T cells into the inflamed skin.
Differential Regulation of Eosinophil Adhesion and Transmigration by Pulmonary Microvascular Endothelial Cells
Authors: Yamamoto Hideaki , Sedgwick Julie B. , Busse William W. 
Published: December 2022

AbstractIn bronchial asthma, eosinophils (EOS) adhere to, and migrate across, the lung microvasculature to exert their effector functions in the airways. This study was conducted to determine the effect of cytokines on adhesion molecule expression on human pulmonary microvascular endothelial cells (HPMEC) and the influence of these molecules on EOS adhesion and transmigration in vitro. Unlike ICAM-1 expression (&gt;80% positive cytokine-treated HPMEC by flow cytometry), VCAM-1 expression varied with the cytokine(s) pretreatment; the order of potency was: TNF-α + IL-4 (82.2 ± 4.2% positive cells) &gt; TNF-α (41.8 ± 5.1%) &gt; IL-1β (20.8 ± 4.7%). IL-4 alone had no effect on either ICAM-1 or VCAM-1 expression. EOS adhesion to cytokine-treated HPMEC followed the same order as that observed for VCAM-1 expression. Interestingly, EOS migration across cytokine-treated HPMEC varied inversely with VCAM-1 expression on, and EOS adhesion to, HPMEC; IL-1β (21.2 ± 1.4% migration) &gt; TNF-α (12.6 ± 2.6%) &gt; TNF-α + IL-4 (9.1 ± 2.0%). EOS adhesion was greatest with TNF-α + IL-4-treated HPMEC, was dependent on VCAM-1, and inhibited with anti-α4 integrin mAb (67.7 ± 7.5% inhibition, p &lt; 0.0005). In contrast, the highest EOS migration occurred across IL-1β-treated HPMEC and was inhibited by anti-β2 integrin mAb (40.4 ± 2.5% inhibition, p &lt; 0.005). Viable HPMEC were required for EOS migration but not adhesion. Our results suggest that EOS adhesion and transmigration are differentially regulated by VCAM-1 and ICAM-1 expression and the interaction of these adhesion proteins with their respective counterligands, i.e., α4 and β2 integrins on EOS.
Inhibition of Inducible Nitric Oxide Synthase by Peroxisome Proliferator-Activated Receptor Agonists: Correlation with Induction of Heme Oxygenase 1
Authors: Colville-Nash Paul R. , Qureshi Saima S. , Willis Dean , Willoughby Derek A. 
Published: December 2022

Abstract
Genetic knock-out in mice of peroxisome proliferator-activated receptor-α (PPARα) can prolong inflammation in response to leukotriene B4. Although cyclooxygenase 2 has been shown to be induced by PPAR activation, the effect of PPAR agonists on the key inflammatory enzyme systems of nitric oxide synthase (NOS) and stress proteins has not been investigated. The effect on these of naturally occurring eicosanoid PPAR agonists (leukotriene B4 and 8(S)-hydroxyeicosatetraenoic acid, which are PPARα selective; PGA2, PGD2, PGJ2, and Δ12PGJ2, which are PPARγ selective) and the synthetic PPARα agonist Wy14,643 was examined in activated RAW264.7 murine macrophages. Leukotriene B4 and 8(S)-hydroxyeicosatetraenoic acid stimulated nitrite accumulation, indicative of enhanced NOS activity. PGA2, PGD2, PGJ2, Δ12PGJ2, and Wy14,643 reduced nitrite accumulation, with Δ12PGJ2 being the most effective. The mechanism behind this reduction was examined using Western blotting. Inhibition of nitrite accumulation was associated with a fall in inducible NOS protein and an induction of heme oxygenase 1, correlating both dose dependently and temporally. Other proteins examined (cyclooxygenase 2, heme oxygenase 2, heat shock protein 70, and glucose-regulated protein 78) were unaffected. The data suggest that naturally occurring PPAR agonists can inhibit the inducible NOS enzyme pathway. This inhibition may be mediated by modulation of the stress protein, heme oxygenase 1. Thus, the generation of eicosanoid breakdown products during inflammation may contribute to its eventual resolution by activation of the PPAR system. This system may thus represent a novel target for therapeutic intervention in inflammatory disease.
Tolerance Induction by Anti-CD2 Plus Anti-CD3 Monoclonal Antibodies: Evidence for an IL-4 Requirement
Authors: Punch Jeffrey D. , Tono Takeshi , Qin Lihui , Bishop D. Keith , Bromberg Jonathan S. 
Published: December 2022

AbstractAnti-CD2 mAb plus anti-CD3 mAb induce alloantigen specific tolerance. We sought to determine whether Th2 cytokines are involved in the induction of tolerance in this model. Addition of anti-IL-4 mAb or anti-IL-10 mAb to anti-CD2 plus anti-CD3 treatment abrogated tolerance and resulted in graft survivals of 26 ± 4 and 25 ± 5 days, respectively. Splenocytes from the anti-IL-4 mAb and anti-IL-10 groups had greater proliferation in response to alloantigen than either tolerant or naive groups. Cytokine analysis of MLR supernatants showed increased IL-10 in the tolerant group and increased IFN-γ in the anti-IL-4 mAb treated group. Donor-specific alloantibody responses in untreated immune animals had a predominantly Th1 (IgG2a) alloantibody response, while the tolerogenic regimen reduced the ratio of IgG2a:IgG1 titers. The addition of anti-IL-4 mAb to the tolerogenic regimen partly restored the Th1-related IgG2a response. Tolerance did not develop in IL-4 knockout animals treated with anti-CD2 plus anti-CD3 (mean graft survival, 27 ± 5 days). Restoration of IL-4 to IL-4 knockout animals by gene transfer with plasmid DNA resulted in prolongation of survival to 46 ± 7 days, while adoptive transfer of wild-type splenocytes into IL-4 knockout recipients resulted in indefinite graft survival (&gt;60 days) and indefinite survival of second donor-type grafts. IL-10 gene transfer to IL-4 knockout recipients did not prolong graft survival (28 ± 4). These results demonstrate that tolerance in this model is mediated at least in part by Th2-type cells that secrete IL-4, promote IL-10 and IgG1 production, and inhibit alloantigen reactivity.
Characterization of a Novel Bax-Associated Protein Expressed in Hemopoietic Tissues and Regulated During Thymocyte Apoptosis
Authors: He Huiling , Hershberger Pamela A. , McCarthy Susan A. 
Published: December 2022

AbstractMembers of the Bcl-2 protein family have been implicated as critical intracellular regulators of apoptosis. Most studies of this protein family have utilized transformed and/or transfected cell lines expressing high levels of these proteins. In the current study, we have analyzed normal murine lymphoid cells and tissues and have detected a previously unreported protein of approximately 16 kDa recognized by an anti-Bax Ab. This 16-kDa protein is abundant in hemopoietic tissues of both wild-type and Bax knock-out mice, it can heterodimerize with Bax in normal lymphocytes, and it is dramatically down-modulated in thymocytes in response to apoptotic stimuli. These results suggest that this protein may have antiapoptotic activity and may participate in the regulation of apoptosis in normal lymphocytes.
Human and Nonhuman Primate Lymphocytes Engrafted into SCID Mice Reside in Unique Mesenteric Lymphoid Structures
Authors: Donze Hollie Hale , Cummins James E. , Schwiebert Rebecca S. , Fultz Patricia N. , Jackson Susan , Mestecky Jiri 
Published: December 2022

AbstractThe present study compares the location and phenotype of B lineage lymphocytes in tissues from SCID mice engrafted with PBMC of human, chimpanzee, and pig-tailed macaque origin. In mice repopulated with both human and nonhuman primate lymphocytes, plasma cells were found in the peritoneal cavity in vascularized structures located in the mesentery near the pancreas, intestines, and spleen. The predominant isotype of the plasma cells was IgG; IgM and IgA cells were also present. κ and λ light chains were expressed by 62% and 38% of the Ig-containing cells, respectively. J chain expression occurred in most cells irrespective of the Ig isotype. In the SCID mice engrafted with human lymphocytes, a few IgM-containing cells were found in the spleen; plasma cells were not found in other tissues, including the intestine. The aggregation of plasma cells did not appear to be a result of infection with EBV. T cells were rarely found in the lymphoid aggregates but were recovered from the spleen and peritoneal lavage. Human Ig levels in the serum of engrafted mice reflected the isotype distribution of the cells with IgG &gt; IgM ≥ IgA.
Generation of Switch Hybrid DNA Between Ig Heavy Chain-μ and Downstream Switch Regions in B Lymphocytes
Authors: Müller Jürgen R. , Giese Thomas , Henry Diane L. , Mushinski J. Frederic , Marcu Kenneth B. 
Published: December 2022

AbstractIg heavy chain isotype switching in B lymphocytes is known to be preceded by transcription of a portion of the particular heavy chain gene segment that is targeted for recombination. Here, we describe an active role for these transcripts in the switch recombination process. Using an in vitro assay that exposes an artificial switch-μ (Sμ) minisubstrate to switch region transcripts in the presence of nuclear extracts from switching cells, we demonstrate that free 3′ ends of the Sμ sequence are extended onto switch region transcripts by reverse transcription. The activity was induced in splenic B lymphocytes upon activation with LPS or CD40 ligand. This in vitro process is thought to be relevant to in vivo class switching for two reasons: 1) although only one-third of the Sμ minisubstrate actually contains Sμ sequence, all crossovers between switch regions occurred in the Sμ portion; and 2) treatment of B lymphocytes with IL-4, which enriches for switching to Sγ1, increases the ratio of Sμ-Sγ1 to Sμ-Sγ3 hybrids by 16% after LPS treatment and by 37% after CD40 ligand activation, implicating this Sμ-primed reverse transcription of switch region transcripts as a novel mechanism of regulating the specificity of isotype switching. Further evidence for an active role of switch region transcripts was obtained by expressing Sα RNA in trans in the Bcl1B1 B lymphoma line. Endogenous Sμ-Sα switch circles were detected in Bcl1B1 cells expressing exogenous Sα RNA but not in mock-transfected cells.
A Developmental Stage-Specific Promoter Directs Germline Transcription of DβJβ Gene Segments in Precursor T Lymphocytes
Authors: Sikes Michael L. , Gomez Rey J. , Song Jing , Oltz Eugene M. 
Published: December 2022

AbstractThe tissue- and stage-specific assembly of Ag receptor genes is regulated by transcriptional control elements positioned within Ig and TCR loci. To further understand the role of cis-acting elements in these regulatory mechanisms, we have characterized a transcriptional promoter that drives germline expression of TCRβ gene segments in vivo. The activity of this promoter, termed PDβ, is restricted to a highly conserved 400-bp region located directly upstream from Dβ1-coding sequences. Maximal PDβ activity requires a TATA element situated within the Dβ1 recombination signal sequences and consensus binding sites for the ubiquitous SP1 and the T cell-specific GATA-3 transcription factors. When linked to active enhancer elements, PDβ directs transcription in most cell types; however, the TCRβ enhancer (Eβ) stimulates PDβ function specifically in precursor T lymphocytes. These findings suggest that PDβ/Eβ interactions may contribute to differential regulation of regions within the TCRβ locus during thymocyte development.
Host NK Cells Are Required for the Growth of the Human Filarial ParasiteBrugia malayiin Mice
Authors: Babu Subash , Porte Patricia , Klei Thomas R. , Shultz Leonard D. , Rajan T. V. 
Published: December 2022

AbstractHuman lymphatic filariasis, which afflicts an estimated 120 million people worldwide, is caused by the large nematode parasites Wuchereria bancrofti and Brugia malayi. Filarial nematodes require both an arthropod vector and a mammalian host to complete their life cycle. Within the definitive (mammalian) host, the lymphatic filarial parasites reside in the lymph nodes and lymphatics, a seemingly hostile environment for infectious agents, since the location exposes them to the immune defenses of the host. We present data here that suggest that the growth of B. malayi in the mammalian host is dependent on host NK cell function. Comparisons of worm survival and development in different strains of mice with varying levels of NK cell activity reveal that NOD/LtSz-scid/scid and NOD/LtSz-scid/scid B2mnull mice (with diminished to absent NK cell activity respectively), are nonpermissive to worm growth, while C.B-17-scid/scid mice with normal NK cell activity are highly permissive. Depletion of NK cells in the permissive C57BL/6J-scid/scid mice renders them nonpermissive to B. malayi growth, whereas stimulation of NK cells in NOD/LtSz-scid/scid mice makes them permissive. Tgε26 mice, which lack NK and T cells, are nonpermissive, but, when reconstituted with NK cells by adoptive transfer of bone marrow cells from C57BL/6J-scid/scid mice, are rendered permissive. This requirement for NK cell activity may explain the site specificity of these parasites. Furthermore, these data suggest that the interaction of the host immune system with the filarial parasite is double edged, with both host protective and parasite growth-promoting activities emanating from the former.