bluuebunny/crossref_metadata_2025_split huggingface dataset:
DNA vaccines against lymphoma: promotion of anti-idiotypic antibody responses induced by single chain Fv genes by fusion to tetanus toxin fragment C.
Authors: Spellerberg M B , Zhu D , Thompsett A , King C A , Hamblin T J , Stevenson F K 
Published: January 2023

Abstract
Idiotypic determinants can act as tumor-associated Ags for B cell lymphoma. Vaccination with idiotypic protein and adjuvant is known to induce specific protection against lymphoma challenge in mice, largely mediated by anti-idiotypic Ab. For facilitating the approach for patients, the V(H) and V(L) genes used to encode the individual idiotypic determinants of each tumor can be obtained by PCR and assembled as single chain Fv (scFv). DNA vaccines containing scFv sequences alone induce low and poorly reproducible levels of anti-idiotypic Ab, likely to be insufficient to suppress tumor in patients. In addition, it may be necessary to break tolerance to Id in tumor bearers. By fusing the gene for fragment C of tetanus toxin to the C terminus of human scFv, we have promoted the anti-scFv Ab response in mice by &gt;50-fold in three of three cases. The induced Abs are mainly against idiotypic determinants, and react specifically with patients' tumor cells, indicating optimal folding of the scFv molecule in the fusion protein. For both antigenic components of the DNA vaccine, the IgG subclass distribution showed a relative increase in IgG2a as compared with vaccination with IgM protein in adjuvant. In patients, the fusion gene should both promote anti-idiotypic Ab and induce Abs against fragment C of tetanus toxin. The latter response would provide a potentially useful comparative measure of the ability of patients to respond to conventional Ag delivered via DNA.
Cutting Edge: The B Cell Surface Protein CD72 Recruits the Tyrosine Phosphatase SHP-1 upon Tyrosine Phosphorylation
Authors: Adachi Takahiro , Flaswinkel Heinrich , Yakura Hidetaka , Reth Michael , Tsubata Takeshi 
Published: January 2023

Abstract
Activation signals of lymphocytes are negatively regulated by the membrane molecules carrying the immunoreceptor tyrosine-based inhibition motif (ITIM). Upon tyrosine phosphorylation, ITIMs recruit SH2-containing phosphatases such as SHP-1, resulting in down-modulation of cell activation. We showed that the cytoplasmic domain of the CD72 molecule carries an ITIM and is associated in vitro with SHP-1 upon tyrosine phosphorylation. Moreover, cross-linking of B cell Ag receptor (BCR) enhances both tyrosine phosphorylation of CD72 and association of CD72 with SHP-1 in B cell line WEHI-231. These results indicate that CD72 recruits SHP-1 upon tyrosine phosphorylation induced by BCR signaling, suggesting that CD72 is a negative regulator of BCR signaling.
A Critical Role for IL-18 in the Proliferation and Activation of NK1.1+CD3− Cells
Authors: Tomura Michio , Zhou Xu-Yu , Maruo Seiji , Ahn Hyun-Jong , Hamaoka Toshiyuki , Okamura Haruki , Nakanishi Kenji , Tanimoto Tadao , Kurimoto Masashi , Fujiwara Hiromi 
Published: January 2023

Abstract
Like IL-12, IFN-γ-inducing factor/IL-18 has been shown to stimulate T cells for IFN-γ production and growth promotion. Considering the NK-stimulatory capacity of IL-12, we investigated the effect of IL-18 on NK lineage cells. A CD4−CD8−surface Ig−Ia− fraction of freshly prepared C57BL/6 spleen cells proliferated strikingly in response to combinations of IL-12 + IL-18 or IL-2 + IL-18, but not to the individual cytokines or IL-2 + IL-12. Cells proliferating in response to IL-2 + IL-18 were NK1.1+CD3−, whereas IL-12 + IL-18-responsive cells were NK1.1−CD3−. Restimulation of the former cells with IL-12 + IL-18 or the latter cells with IL-2 + IL-18 resulted in the generation of NK1.1−CD3− or NK1.1+CD3− cells, respectively. Moreover, a NK1.1+CD3−CD4−CD8−surface Ig−Ia− population isolated from spleen cells was found to form NK1.1+CD3− or NK1.1−CD3− blasts by stimulation with IL-2 + IL-18 or IL-12 + IL-18, respectively, and the NK1.1 positivity on these blasts was again reversed after restimulation with an alternative combined stimulus. Both types of blasts produced enormously large amounts of IFN-γ in response to IL-12 + IL-18 and exhibited strikingly high levels of NK activity. These results indicate that IL-18 plays an obligatory role in inducing proliferation and activation of NK1.1+CD3−CD4−CD8− cells and that the expression of the NK1.1 marker is reversible, depending on the cytokine used for stimulation in combination with IL-18.
Pairing of Variable Heavy and Variable κ Chains in Individual Naive and Memory B Cells
Authors: Brezinschek Hans-Peter , Foster Sandra J. , Dörner Thomas , Brezinschek Ruth I. , Lipsky Peter E. 
Published: January 2023

Abstract
A functional Ig consists of two heterodimers each of which is composed of a heavy and a light chain. Although there is increasing knowledge about the events that govern the rearrangement of the genes encoding each individual chain, only very limited information is available about the mechanisms governing the pairing of variable heavy (VH) and variable light (VL) chains. Using a single cell PCR, we were able to obtain VH and Vκ chains from 144 individual human CD19+/IgM+ B cells. Pairing of specific VH or Vκ families was not observed, nor was the length or the amino acid composition of the CDR3s of VH and Vκ chains in individual B cells similar. Comparison of VH and Vκ genes in B cells in which one or both contained evidence of somatic hypermutation with those with no mutations revealed a significant decrease in the mean length of the VH CDR3. Moreover, there was a significant correlation between the frequencies of mutations in VH and Vκ gene pairs in individual B cells. These results indicate that Ag-mediated selection as opposed to VHDJH recombination or subsequent Ig chain pairing tended to approximate the CDR3 lengths and the frequency of mutations of VH and Vκ in individual B cells.
Phosphorylation Regulates the Delivery of MHC Class II Invariant Chain Complexes to Antigen Processing Compartments
Authors: Anderson Howard A. , Roche Paul A. 
Published: January 2023

Abstract
Transport of newly synthesized MHC class II glycoproteins to endosomal Ag processing compartments is mediated by their association with the invariant chain (Ii). Targeting to these compartments is dependent upon recognition of leucine-based endosomal/lysosomal targeting motifs in the Ii cytosolic domain. Ii, like many molecules that contain leucine-based endosomal targeting motifs, is phosphorylated in vivo. In this report we demonstrate that the cytosolic domain of the p35 Ii isoform is phosphorylated in class II Ii complexes isolated from human B lymphoblastoid cell lines or freshly obtained PBMC. Mutation of serine residue 6 or 8 prevents phosphorylation of Ii-p35 expressed in HeLa cells. Treatment of B lymphoblastoid cell lines with the serine/threonine kinase inhibitor staurosporine prevented Ii phosphorylation and significantly delayed trafficking of newly synthesized class II Ii complexes to endosomal Ag processing compartments. By contrast, staurosporine had no effect on the rate of transport of class I or class II glycoproteins through the Golgi apparatus and did not inhibit the delivery of the chimeric molecule Tac-DMβ to endocytic compartments, suggesting that staurosporine does not nonspecifically inhibit protein transport to the endocytic pathway. These results demonstrate that phosphorylation regulates the efficient targeting of MHC class II Ii complexes to Ag processing compartments and strongly suggest that this effect is mediated by phosphorylation of the MHC class II-associated Ii chain.
Phosphorylation of FADD/MORT1 and Fas by Kinases That Associate with the Membrane-Proximal Cytoplasmic Domain of Fas
Authors: Kennedy Norman J. , Budd Ralph C. 
Published: January 2023

Abstract
Fas (Apo-1, CD95), a member of the TNFR family, is expressed on a variety of cell types and transduces an apoptotic signal. Since Fas does not possess known enzymatic activities, proteins that interact with the cytoplasmic domain of Fas regulate the death signal. Several proteins have been identified, primarily using the yeast two-hybrid system, that associate with the death domain of Fas. One of these proteins, FADD/MORT1, can be phosphorylated, although the kinase that is responsible has not been identified. Furthermore, direct signaling connections between Fas and its known activation of sphingomyelinase or NF-κB have not been made, suggesting that other proteins may associate with Fas. In this study, a series of glutathione S-transferase fusion proteins was constructed that contained the cytoplasmic domain of murine Fas. These proteins were used to search for additional proteins that associate with Fas. Novel proteins, including kinases, were identified that associated specifically with the membrane-proximal, cytoplasmic tail of Fas but not with the death domain. One of these kinases phosphorylates FADD/MORT1. Moreover, the membrane-proximal region of Fas itself was phosphorylated by one of the associating kinases. These findings suggest that, similar to the Fas-related p55 TNFR, the membrane-proximal region of Fas likely participates in signaling.
Polymorphism in the Iα1 Germ-Line Transcript Regulatory Region and IgA Productivity in Patients with IgA Nephropathy
Authors: Yano Naohiro , Asakura Kumiko , Endoh Masayuki , Abe Yoshifumi , Nomoto Yasuo , Sakai Hideto , Kurokawa Kiyoshi , Tsukamoto Hideo 
Published: January 2023

Abstract
Enhanced in vivo and in vitro production of IgA has been reported in patients with IgA nephropathy (IgAN) and their family members. It is generally considered that IgA1 is a prominent subclass of IgA in IgAN. Although genetic mechanisms of IgA class switch recombination in IgAN have been studied enthusiastically, the critical factors that induce IgA1-specific class switching in IgAN have yet to be elucidated. A large body of data indicates that the germ-line transcript of Ig constant region (CH) genes that precedes actual class switching has regulatory effects on class switch recombination. To analyze structural abnormalities in the Iα1 germ-line transcript regulatory gene, a region about 1000 bp long located upstream of Iα1 exons was surveyed by the PCR-single strand conformation polymorphism method, and the polymorphism detected was confirmed by subsequent DNA sequencing. Three hot spots for point mutation were detected upstream of the promoter region of the Iα1 germ-line transcript, and the mutations were observed more frequently in patients than in controls. Patients with the mutations showed higher levels of serum IgA and higher in vitro IgA synthesis. In the luciferase assay, the regulatory gene with the mutations showed a potent effect for induction of the Iα1 germ-line transcript. The polymorphism in the Iα1 regulatory region possibly causes enhanced IgA production in some patients with IgAN.
HLA-E Surface Expression Depends on Binding of TAP-Dependent Peptides Derived from Certain HLA Class I Signal Sequences
Authors: Lee Ni , Goodlett David R. , Ishitani Akiko , Marquardt Hans , Geraghty Daniel E. 
Published: January 2023

Abstract
Previous studies showed that HLA-E was expressed in lymphoblastoid cell line (LCL) 721.221 cells, but surface expression was lacking. To determine the signals controlling surface expression, we constructed a series of hybrid genes using complementary portions derived from the HLA-E and HLA-A2 genes. In this manner, a hybrid of HLA-E was identified, designated AEH, which differed from HLA-E by having the HLA-A2 signal sequence substituting for the HLA-E leader peptide. Transfection of LCL 721.221 cells with AEH induced HLA-E surface expression. Analysis of peptides bound to HLA-E revealed that a nonamer peptide derived from the A2 signal sequence was the predominant peptide bound. LCL 721.221 cells transfected with certain class I genes, including HLA-G, were also sufficient to promote peptide binding and HLA-E surface expression without increasing the level of HLA-E heavy chain synthesis. Peptides bound to HLA-E consisted of nine amino acids, with methionine at position 2 and leucine in the carboxyl-terminal position, and were nearly identical to the leader sequence-derived peptide previously shown to be a predominant peptide bound to the murine Qa-1 Ag. Signal peptides derived from certain HLA-B proteins with threonine in position 2 only marginally up-regulated HLA-E surface expression in .221 cells. An examination of HLA-E peptide binding in the TAP negative cell line .134 indicated that peptide binding to HLA-E was dependent on a functional TAP heterodimer regardless of whether peptide was available in cis, as in the AEH construct, or in trans, as in the class I transfectants of .221 cells.
TGF-β1 as an Endogenous Defender Against Macrophage-Triggered Stromelysin Gene Expression in the Glomerulus
Authors: Kitamura Masanori 
Published: January 2023

Abstract
Recent investigation has indicated that TGF-β1, the macrophage (Mφ) deactivator, may attenuate Mφ-mediated acute glomerular injury. Using stromelysin as an indicator, this study investigated whether and how endogenous TGF-β1 modulates the glomerular cell activation triggered by Mφ. Rat mesangial cells were stably transfected with a cDNA encoding the active form of TGF-β1 and a cDNA coding for a dominant-negative mutant of the TGF-βR type II. Compared with mock-transfected cells, TGF-β1 transfectants exhibited blunted expression of stromelysin in response to the Mφ-derived, inflammatory cytokine IL-1β. In contrast, mesangial cells expressing the dominant-interfering TGF-βR showed enhanced expression of stromelysin in response to IL-1β, suggesting that endogenous TGF-β functions as an autocrine inhibitor of the IL-1 response. In isolated, normal rat glomeruli, externally added TGF-β1 suppressed the induction of stromelysin by mediators that were elaborated by activated Mφ. Similarly, when isolated, nephritic glomeruli producing the active form of TGF-β1 were stimulated by IL-1β or Mφ-conditioned medium, the induction of stromelysin was dramatically suppressed as compared with normal glomeruli. To investigate whether endogenous TGF-β1 affects the glomerular cell activation triggered by Mφ, a technique for adoptive Mφ transfer was used. LPS-stimulated reporter Mφ were transferred into either normal rat glomeruli or nephritic glomeruli expressing active TGF-β1. In the normal glomeruli, stromelysin expression was markedly induced in resident cells after the transfer of activated Mφ. This induction was substantially repressed in those glomeruli producing active TGF-β1. These results reinforce the idea that TGF-β1 is an endogenous defender that attenuates certain actions of infiltrating Mφ in the glomerulus.
In Vivo Effects of a Bacterial Superantigen on Macaque TCR Repertoires
Authors: Kou Zhong-Chen , Halloran Matilda , Lee-Parritz David , Shen Ling , Simon Meredith , Sehgal Prabhat K. , Shen Yun , Chen Zheng W. 
Published: January 2023

Abstract
A macaque model was employed to explore staphylococcal enterotoxin B (SEB) superantigen-driven T lymphocyte responses. The SEB-reactive Vβ+ cell subpopulations demonstrated a striking tri-phase response in rhesus monkeys following an SEB challenge in vivo. The hyperacute down-regulation, seen as early as 2 h through 2 days after SEB injection, was characterized by a disappearance of the reactive Vβ-restricted PBL subpopulations from the circulation and decreased expression of these cell subpopulations in lymphoid tissues. Following this, a dominant expansion of reactive Vβ-expressing CD4+ cell subpopulations occurred in lymph nodes and spleens, whereas in the peripheral blood a preferential expansion of reactive Vβ-expressing CD8+ cell subpopulations was seen. An exhaustion of this response was then seen, with a prolonged decrease in the number of the reactive Vβ+ CD4+ lymphocyte subpopulations. Interestingly, monoclonal or oligoclonal dominance was seen in the reactive Vβ+ cell subpopulations in the period of the transition from the polyclonal cellular expansion to the exhaustion of the response, suggesting that some Vβ+ cell clones may be more resistant than others to superantigen-mediated depletion. These results indicate that in vivo SEB superantigen-mediated effect on lymphocyte subpopulations in macaques is complex, suggesting that profound dynamics in the TCR repertoires may in part account for the susceptibility of higher primates to SEB-induced diseases.
Cytokine Gene Therapy in Experimental Allergic Encephalomyelitis by Injection of Plasmid DNA-Cationic Liposome Complex into the Central Nervous System
Authors: Croxford J. Ludovic , Triantaphyllopoulos Kostas , Podhajcer Osvaldo L. , Feldmann Marc , Baker David , Chernajovsky Yuti 
Published: January 2023

Abstract
Experimental allergic encephalomyelitis (EAE) is an autoimmune disease of the central nervous system with many similarities to multiple sclerosis. The main effector cells involved are CD4+ T cells, recognizing encephalitogenic epitopes within the central nervous system, and macrophages, both of which secrete proinflammatory cytokines, such as IFN-γ and TNF. Studies have shown that immunomodulation of this inflammatory response by anti-inflammatory cytokines (IL-4, IL-10, IFN-β, and TGF-β) can reduce clinical severity in EAE. The importance of TNF in EAE has been demonstrated by using soluble TNF-receptor molecules to inhibit EAE. However, the limitation of this type of therapy is the necessity for frequent administration of cytokine proteins due to their short biologic half-life. This study demonstrates that EAE can be inhibited by a single injection of therapeutic cytokine (IL-4, IFN-β, and TGF-β) DNA-cationic liposome complex directly into the central nervous system. DNA coding for a novel, dimeric form of human p75 TNF receptor also ameliorated clinical EAE. Local administration of DNA-cationic liposome complex has identified gene targets that may be more efficiently exploited using vectors producing more stable expression for effective treatment of neuroimmunologic disease.
Short Peptide-Based Tolerogens Without Self-Antigenic or Pathogenic Activity Reverse Autoimmune Disease
Authors: Karin Nathan , Binah Ofer , Grabie Nir , Mitchell Dennis J. , Felzen Bella , Solomon Matthew D. , Conlon Paul , Gaur Amitabh , Ling Nicholas , Steinman Lawrence 
Published: January 2023

Abstract
An immunodominant epitope of myelin basic protein (MBP), VHFFKNIVTPRTP (p87–99), is a major target of T cells in brain lesions of multiple sclerosis (MS), and this peptide can trigger experimental autoimmune encephalomyelitis (EAE). We designed truncated peptides based on this pathogenic 13-mer that are not antigenic. These short peptides reduced production of IFN-γ and TNF-α in vivo. Moreover, paraplegic rats given the 7-mer FKNIVTP in soluble form showed total reversal of paralysis in 24 h. Truncated peptides that are too small to stimulate antigenic responses to pathogenic regions of myelin basic protein are nevertheless effective tolerogens and are able to anergize autoreactive T cells. Short peptide-based tolerogens, devoid of immunogenic and pathogenic potential, may be attractive for therapy of autoimmune diseases.
Treponema pallidumandBorrelia burgdorferiLipoproteins and Synthetic Lipopeptides Activate Monocytic Cells via a CD14-Dependent Pathway Distinct from That Used by Lipopolysaccharide
Authors: Sellati Timothy J. , Bouis Deborah A. , Kitchens Richard L. , Darveau Richard P. , Pugin Jerome , Ulevitch Richard J. , Gangloff Sophie C. , Goyert Sanna M. , Norgard Michael V. , Radolf Justin D. 
Published: January 2023

AbstractLipoproteins of Treponema pallidum and Borrelia burgdorferi possess potent proinflammatory properties and, thus, have been implicated as major proinflammatory agonists in syphilis and Lyme disease. Here we used purified B. burgdorferi outer surface protein A (OspA) and synthetic lipopeptides corresponding to the N-termini of OspA and the 47-kDa major lipoprotein immunogen of T. pallidum to clarify the contribution of CD14 to monocytic cell activation by spirochetal lipoproteins and lipopeptides. As with LPS, mouse anti-human CD14 Abs blocked the activation of 1,25-dihydroxyvitamin D3-matured human myelomonocytic THP-1 cells by OspA and the two lipopeptides. The existence of a CD14-dependent pathway was corroborated by using undifferentiated THP-1 cells transfected with CD14 and peritoneal macrophages from CD14-deficient BALB/c mice. Unlike LPS, cell activation by lipoproteins and lipopeptides was serum independent and was not augmented by exogenous LPS-binding protein. Two observations constituted evidence that LPS and lipoprotein/lipopeptide signaling proceed via distinct transducing elements downstream of CD14: 1) CHO cells transfected with CD14 were exquisitely sensitive to LPS but were lipoprotein/lipopeptide nonresponsive; and 2) substoichiometric amounts of deacylated LPS that block LPS signaling at a site distal to CD14 failed to antagonize activation by lipoproteins and lipopeptides. The combined results demonstrate that spirochetal lipoproteins and lipopeptides use a CD14-dependent pathway that differs in at least two fundamental respects from the well-characterized LPS recognition pathway.
Control ofLeishmania majorInfection in Mice Lacking TNF Receptors
Authors: Nashleanas Michelle , Kanaly Suzanne , Scott Phillip 
Published: January 2023

AbstractTNF participates in the induction of nitric oxide (NO) production and macrophage activation, leading to the elimination of intracellular pathogens. We previously found that TNF receptor p55-deficient mice (TNFRp55−/−) control replication of Leishmania major in vivo but fail to resolve their lesions. Here we report that mice lacking the p75 receptor (TNFRp75−/−) or both receptors (TNFRp55p75−/−), also control parasite replication, albeit mice lacking the p55 receptor (either TNFRp55−/− or TNFRp55p75−/−) are delayed in their elimination of L. major compared with controls. All TNF receptor-deficient mice developed a Th1-type immune response and up-regulated inducible NO synthase (iNOS) mRNA gene expression in lesions during infection. Thus, neither TNF receptor appears to be absolutely required for NO production or elimination of L. major in vivo. In vitro, however, while macrophages from naive TNFRp75−/− mice could be activated to produce NO and kill L. major, we observed a defect in NO production and parasite killing by resident peritoneal macrophages from naive TNFRp55−/− or TNFRp55p75−/− mice. However, when macrophages were elicited with leishmanial Ag from 4-wk-infected TNFRp55−/−or TNFRp55p75−/− mice, they produced NO and were leishmanicidal. These data suggest that the TNFRp75 plays no essential role in L. major infection in mice and that the p55 receptor may be required for optimal macrophage activation. However, the results also show that a mechanism exists by which macrophages can be primed in vivo during L. major infection to produce NO and kill L. major in the absence of signaling through either of the TNF receptors.