bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship between disease severity and responses by blood mononuclear cells from patients with rheumatoid arthritis to human heat‐shock protein 60
Authors: Macht L. M. , Elson C. J. , Kirwan J. R. , Gaston J. S. H. , Lamont A. G. , Thompson J. M. , Thompson S. J. 
Published: March 2003

SummaryThe hypothesis that T‐cell responses to the 60 000 MW family of heat‐shock proteins (hsp) may be related to the severity of rheumatoid arthritis (RA) was examined. Peripheral blood mononuclear cells (PBMC) from most normal individuals and both early and established RA patients proliferated in vitro in response to human hsp 60 and mycobacterial hsp 65 as well as tetanus toxoid (TT) and mycobacterial purified protein derivative (PPD). PBMC from some patients with established RA gave responses to hsp 60 that were above the normal range and/or peaked earlier than PBMC from normal individuals. The responses of PBMC from established RA to hsp 65, but not PPD or TT, were also higher than those from normal individuals, but the peak responses to all three antigens appeared delayed. Thus a selective increase in responsiveness to hsp 60 develops with disease duration in many RA patients. Six assessments of disease activity and severity were made but apart from rheumatoid factor titre, they were unrelated to the proliferative response. Similarly, disease activity and severity did not differ between those RA patients whose hsp 60 stimulated cells produced interferon‐γ and those who did not, although patients whose hsp 60‐stimulated T cells produced interleukin‐4 (IL‐4) and/or IL‐10, appeared to have less disease activity and severity than those who did not. Significant negative correlations were found between IL‐10 production by hsp 60‐stimulated cells and disease assessments. It is considered that RA is less severe in those patients whose hsp 60‐stimulated cells produce T‐helper 2 type cytokines.
Immunization onto bare skin with heat‐labile enterotoxin of Escherichia coli enhances immune responses to coadministered protein and peptide antigens and protects mice against lethal toxin challenge
Authors: Beignon A.‐S. , Briand J.‐P. , Muller S. , Partidos C. D. 
Published: March 2003

SummaryIn this study, the potential of the bare skin as a non‐invasive route for vaccination was examined. Following application of heat‐labile enterotoxin (LT) of Escherichia coli onto bare skin of BALB/c mice, strong serum anti‐LT antibody responses were observed, and mucosal immunoglobulin A (IgA) and IgG antibodies were measured in vagina washes. In addition, LT enhanced the serum and mucosal antibody and proliferative T‐cell responses to the model protein antigen β‐galactosidase (β‐gal) when coadministered onto bare skin, highlighting its potential to exert an adjuvant effect. When a peptide representing a T‐helper epitope (aa 307–319) from the haemagglutinin of influenza virus was applied onto bare skin with LT or cholera toxin (CT), it primed effectively peptide‐ and virus‐specific T cells, as measured in vitro by the interleukin‐2 (IL‐2) secretion assay. LT was shown to be as immunogenic as CT. Binding activity to GM1 gangliosides was essential for effective induction of anti‐CT serum and mucosal antibody responses. Finally, mice immunized onto bare skin with LT were protected against intraperitoneal challenge with a lethal dose of the homologous toxin. These findings give further support to a growing body of evidence on the potential of skin as a non‐invasive route for vaccine delivery. This immunization strategy might be advantageous for vaccination programmes in Third World countries, because administration by this route is simple, painless and economical.
Mechanism and therapeutic potential of DNA‐based immunization against the envelope proteins of hepatitis B virus in normal and transgenic mice
Authors: Oka Yuichiro , Fazle Akbar S. M. , Horiike Norio , Joko Kouji , Onji Morikazu 
Published: March 2003

SummaryTwo plasmid DNA vectors, pCAGGS(S) encoding the genes of the major envelope protein of hepatitis B virus (HBV), and pCAGGS(S + preS2) encoding the genes of the middle envelope protein were used to study the mechanism and therapeutic potential of DNA‐based immunization. Injection of these plasmids into the regenerating bilateral tibialis anterior muscle (TA) of normal C57BL/6 mice induced hepatitis B surface antigen (HBsAg)‐specific humoral and cellular immune responses. Seventy‐two hours after injection of pCAGGS(S), infiltrating cells including antigen‐presenting dendritic cells (DC) were localized around the injection site and HBsAg was expressed by both muscle cells and infiltrating cells. Spleen DC from the mice were exposed to HBsAg for up to 32 weeks after a single injection of pCAGGS(S), because these DC induced the proliferation of HBsAg‐specific memory lymphocytes in culture without exogenous HBsAg. A single injection of pCAGGS(S) or pCAGGS(S + preS2) resulted in the clearance of HBsAg in 28 out of 30 HBV‐transgenic (Tg) mice. In contrast, more than 7 monthly injections of an HBsAg‐based vaccine were required for the clearance of HBsAg in 6 out of 29 HBV‐Tg mice. Infiltrating DC at the DNA vaccine injection site may have a role in initiating HBsAg‐specific immune response, whereas the persistence of HBsAg exposed spleen DC may contribute to long‐lasting immunity. This study also suggested that DNA‐based vaccines may be a potent tool for treating chronic HBV carriers.
Extinction of expression of the genes encoding haematopoietic cell‐restricted transcription factors in T‐lymphoma × fibroblast cell hybrids
Authors: Oikawa Tsuneyuki , Yamada Toshiyuki , Kondoh Nobuo , Negishi‐Kihara Fumiko , Hitomi Yoshiaki , Suzuki Mitsuhiro , Teramoto Sayaka 
Published: March 2003

SummaryWe previously reported that expression of the T‐cell receptor (TCR) α and lck genes is extinguished in hybrids between mouse T‐lymphoma EL4 cells and mouse fibroblast B82 cells. In the present study, we found that the activities of the TCRα minimum enhancer and the lck promoter monitored by the luciferase or chloramphenicol acetyltransferase (CAT) assays were markedly inhibited in the hybrids. Expression of the TCF‐1, LEF‐1, GATA‐3, Ikaros, c‐myb and Fli‐1 genes, which encode the haematopoietic cell‐restricted transcription factors that appear to be responsible for the activities of the enhancer and the promoter, was fully extinguished or markedly suppressed in the hybrids. On the other hand, expression of the transcription factor genes observed in both parental cells, such as the AML1 and c‐ets‐1 genes, and that of the genes encoding ubiquitously expressed transcription factors, such as the E2A, CREB and c‐ets‐2 genes, was not significantly suppressed in the hybrids. These results suggest that the genes encoding haematopoietic cell‐restricted transcription factors are targets for negative regulation in fibroblastic background and that the repression of these genes may consequently lead to suppression of the promoter and/or enhancer activities of several T‐cell‐specific structural genes in T‐lymphoma × fibroblast cell hybrids.
Blockage of complement regulators in the conjunctiva and within the eye leads to massive inflammation and iritis
Authors: Bardenstein David S , Cheyer Christopher J , Lee Chieh , Cocuzzi Enzo , Mizuno Masashi , Okada Noriko , Medof M. Edward 
Published: March 2003

SummaryThe open environment of the eye is continuously subject to an influx of foreign agents that can activate complement. Decay‐accelerating factor (DAF), membrane cofactor protein (MCP) and CD59 are regulators that protect self‐cells from autologous complement activation on their surfaces. They are expressed in the eye at unusually high levels but their physiological importance in this site is unstudied. In the rat, a structural analogue termed 5I2 antigen (5I2 Ag) has actions overlapping DAF and MCP. In this investigation, we injected F(ab′)2 fragments of 5I2 mAb into the conjunctiva and aqueous humor, in the latter case with and without concomitant blockage of CD59. Massive neutrophilic infiltration of the stroma and iris resulted upon blocking 5I2 Ag activity. Frank necrosis of the iris occurred upon concomitant intraocular blockage of CD59. C3b was identified immunohistochemically, and minimal effects were seen in complement‐depleted animals and in those treated with non‐relevant antibody. The finding that blockage of 5I2 Ag function in periocular tissues and within the eye causes intense conjunctival inflammation and iritis demonstrates the importance of intrinsic complement regulators in protecting ocular tissues from spontaneous or bystander attack by autologous complement.
All‐trans‐retinoic acid and polyriboinosinic : polyribocytidylic acid in combination potentiate specific antibody production and cell‐mediated immunity
Authors: DeCicco Kathleen L. , Youngdahl John D. , Ross A. Catharine 
Published: March 2003

SummaryRetinoic acid (RA), an active metabolite of vitamin A, may synergize with interferons (IFN) to evoke a heightened immune response, suggesting combination therapy as a promising treatment for various cancers. Recently, we demonstrated a strong synergism between RA and polyriboinosinic : polyribocytidylic acid (PIC), an inducer of IFN, on antibody production in immunocompromised vitamin A‐deficient animals. In the present study, we examined whether this combination could potentiate T‐cell‐dependent antibody production in non‐immunocompromised rats. Forty male Lewis rats were treated with 100 µg all‐trans‐RA, 20 µg PIC, or the combination in either an 11‐d study to evaluate antibody production, changes in lymphocyte populations, and cell proliferation, or a 21‐hr study to evaluate early changes in lymphocyte populations and gene expression. The combination of RA + PIC significantly potentiated anti‐tetanus IgG levels (P < 0·002). Similarly, this combination also increased the numbers of B cells and major histocompatibility complex (MHC) class II+ cells in spleen and lymph nodes, and natural killer (NK) cells in spleen and blood (P < 0·05). RA + PIC‐treated rats had significantly higher levels of interleukin (IL)‐10, IL‐12, and signal transducer and activator of transcription‐1 (STAT‐1) mRNA (P < 0·05), and STAT‐1 protein (P < 0·02). Treatments administered in vivo significantly modulated T‐cell proliferation to anti‐CD3/phorbol myristyl acetate + IFN‐αex vivo. These changes in antibody production, cell distribution, cytokine gene expression, and T‐cell proliferation suggest that the combination of RA + PIC stimulates humoral and cell‐mediated immunity, and deserves further testing in models of cancer chemoprevention in vivo.
CR2‐mediated activation of the complement alternative pathway results in formation of membrane attack complexes on human B lymphocytes
Authors: Nielsen Claus H. , Marquart Hanne V. , Prodinger Wolfgang M. , Leslie Robert G. Q. 
Published: March 2003

SummaryNormal human B lymphocytes activate the alternative pathway of complement via complement receptor type 2 (CR2, CD21), that binds hydrolysed C3 (iC3) and thereby promotes the formation of a membrane‐bound C3 convertase. We have investigated whether this might lead to the generation of a C5 convertase and consequent formation of membrane attack complexes (MAC). Deposition of C3 fragments and MAC was assessed on human peripheral B lymphocytes in the presence of 30% autologous serum containing 4·4 mm MgCl2/20 mm EGTA, which abrogates the classical pathway of complement without affecting the alternative pathway. Blockade of the CR2 ligand‐binding site with the monoclonal antibody FE8 resulted in 56 ± 13% and 71 ± 9% inhibition of the C3‐fragment and MAC deposition, respectively, whereas the monoclonal antibody HB135, directed against an irrelevant CR2 epitope, had no effect. Blockade of the CR1 binding site with the monoclonal antibody 3D9 also resulted in a minor reduction in MAC deposition, while FE8 and 3D9, in combination, markedly reduced deposition of both C3 fragments (91 ± 5%) and C9 (95 ± 3%). The kinetics of C3‐fragment and MAC deposition, as well as the dependence of both processes on CR2, indicate that MAC formation is a consequence of alternative pathway activation.
Age‐dependent increase of peritoneal B‐1b B cells in SCID mice
Authors: Hinkley Kirk S. , Chiasson Rod J. , Prior Tracey K. , Riggs James E. 
Published: March 2003

SummaryThe impact of increasing age upon immunoglobulin production and B‐lymphocyte generation in ‘leaky’ severe combined immune‐defective (SCID) mice was examined by enzyme‐linked immunosorbent assay and flow cytometry. By 1 year of age, the mice had normal numbers of B cells in their peritoneal cavity, while their spleen had very few immunoglobulin M‐positive (IgM+) cells. The majority of B cells expressed the CD11b marker characteristic of the B‐1b subset. B‐1a (CD5+) cells were present at a lower frequency and B‐2 cells were absent. The frequency of mice producing detectable immunoglobulin increased with age, and isotype diversity within individual mice was variable. IgM production was most frequently observed followed by IgG3 and IgG2a, then IgG1, and finally IgA. The selective persistence of the B‐1 B‐cell subset in the peritoneal cavity of aging SCID mice is a natural model for the study of those genetic and environmental influences that determine lymphocyte longevity.
Purified protein derivative of tuberculin upregulates the expression of vascular endothelial growth factor in T lymphocytes in vitro
Authors: Matsuyama Wataru , Kubota Ryuji , Hashiguchi Teruto , Momi Hiroaki , Kawabata Masaharu , Nakagawa Masanori , Arimura Kimiyoshi , Osame Mitsuhiro 
Published: March 2003

SummaryThe purpose of this study was to investigate the cellular source and significance of vascular endothelial growth factor (VEGF) which, as reported previously, is elevated in the sera of pulmonary tuberculous patients. We obtained peripheral blood mononuclear cells (PBMCs) from 28 patients with active pulmonary tuberculosis, from 11 healthy controls who were positive for purified protein derivative of tuberculin (PPD), and from eight healthy individuals who were negative for PPD. We incubated the PBMCs with PPD in the presence or absence of major histocompatibility (MHC) class I or class II antibody in vitro, and measured the VEGF levels of culture supernatants. We also analysed the source of cells that secrete VEGF by using flow cytometry with intracellular staining. The T lymphocytes of active tuberculous patients secreted a higher level of VEGF than those of healthy controls. This production of VEGF was inhibited by adding MHC class II antibody. The addition of MHC class I antibody, however, did not inhibit. We propose that CD4+ T lymphocytes are almost certainly the cells that produce VEGF in response to PPD. VEGF production might be associated with an antigen‐specific immune reaction via CD4+ T lymphocytes in tuberculosis.
Staphylococcal enterotoxin H contrasts closely related enterotoxins in species reactivity
Authors: Pettersson Helen , Forsberg Göran 
Published: March 2003

Summary Staphylococcus aureus enterotoxin H (SEH) belongs to the staphylococcal enterotoxin (SE) family of superantigens (SAgs). SEH has structural similarities to other SE; however, its biological properties are less well characterized. SEH binds with high affinity to human major histocompatibility complex (MHC) class II and exhibits strong mitogenic activity in human T cells, although it was found to be less potent than the related SEA. Surprisingly and in sharp contrast to related SEs, SEH did not possess superantigen activity in murine T cells and T cells from three investigated rat strains. However, SEH bound to a high extent to murine MHC class II expressing cells and when presented by these cells SEH stimulated human T cells to proliferate. Thus, SEH interacts with the murine MHC class II molecule in a functional manner. Notably, SEH had an inhibitory effect on murine SEA response, demonstrating that SEH interferes with the SEA interactions with murine cells. Despite this, murine T cells did not proliferate regardless of whether SEH was presented on human or murine MHC class II expressing cells. Consequently, SEH differs in species reactivity as compared to related SEs and lacks critical properties for T‐cell activation in mice. We propose that unlike other SEs, SEH does not interact with murine T cells since it is not recognized by murine T‐cell receptors.
Involvement of tumour necrosis factor‐α‐related apoptosis‐inducing ligand in enhanced cytotoxicity of lipopolysaccharide‐stimulated dendritic cells to activated T cells
Authors: Yu Yizhi , Liu Shuxun , Wang Wenya , Song Wengang , Zhang Minghui , Zhang Weiping , Qin Zhihai , Cao Xuetao 
Published: March 2003

SummaryDendritic cells (DC) are potent antigen‐presenting cells (APC) specialized in T‐cell mediated immune responses, and also play critical roles in the homeostasis of T cells for controlling immune responses. In the present study, we demonstrated that during mouse bone‐marrow‐derived DC activation of ovalbumin (OVA)‐specific Ia‐kb‐restricted T hybridoma cells, MF2.2D9 and OVA257–264‐specific H‐2kb‐restricted RF33.70 T cells, respectively, both hybridomas undergo cell death, partially mediated via apoptotic ligand–tumour necrosis factor‐α (TNF‐α)‐related apoptosis‐inducing ligand (TRAIL). Lipopolysaccharide enhanced the cytotoxic effect on the two activated T hybridoma cells, which was correlated with up‐regulation of TRAIL‐expression on DC to some extent. The activation of caspase‐3 in activated T hybridoma cells cocultured with DC contributed to the programmed cell death pathway T cells underwent. Therefore, our results show that activation‐induced cell death of T hybridoma cells can be influenced by DC, suggesting that DC may be involved in elimination of activated T cells at the end of primary immune responses.
Circulating immunoglobulin A‐ and immunoglobulin G‐secreting hybridoma cells in peripheral blood preferably migrate to female genital tracts. The role of sex hormones
Authors: Wang Xiaolei , Zhao Xudong , Ben Kunlong , Cao Xiaomei , Wang Yuqi , Zhou Hongming 
Published: March 2003

SummaryAntigen‐specific circulating immunoglobulin‐secreting cells (ISC) migrate to various secondary and tertiary lymphoid tissues. To understand the migration of the cells into the genital tract and its regulation by sex hormones, spleen‐derived SG2 hybridoma cells secreting immunoglobulin G2b (IgG2b) and Peyer's patch‐derived PA4 hybridoma cells secreting polymer IgA were labelled with 3H‐TdR, and intravenously injected into syngeneic mice of both sexes. Using flow cytometry, surface molecular markers of plasma cells, CD38 and CD138, and adhesion molecules, CD49d, CD162, and CD11a were found to be positive in SG2 and PA4 cells, but CD62L, α4β7 and CD44 were not expressed on these cells. The relative distribution indexes (RDIs) of the cells in genital tract and other tissues were measured. The means of RDIs of SG2 and PA4 cells in female genital tissues were 6·5 and 4·5 times as many as the means in male genital tissues, respectively. The treatment of ovariectomized mice with β‐oestradiol significantly increased the RDIs of PA4 cells in cervix and vagina, but decreased the RDIs of SG2 cells in vagina, horn of uterus, uterus and rectum (P<0·05). Progesterone treatment increased the RDIs of PA4 cells in vagina and rectum (P<0·05). The treatment with testosterone significantly increased the RDIs of SG2 and PA4 cells in epididymis and accessory sex glands (P<0·05). These results demonstrate that the female genital tract is the preferable site for the migration of circulating hybridoma cells to the male genital tract, and sex hormones play an important role in regulation of the migration of circulating ISC to genital tracts.
Irradiation up‐regulates CD80 expression through induction of tumour necrosis factor‐α and CD40 ligand expression on B lymphoma cells
Authors: Ishikawa Fumio , Nakano Hideki , Seo Akira , Okada Yayoi , Torihata Hideko , Tanaka Yuriko , Uchida Tetsuya , Miyake Hidekazu , Kakiuchi Terutaka 
Published: March 2003

SummaryPreviously, we reported that 100 Gy X‐ray irradiation followed by 24 hr incubation up‐regulates CD80 expression in murine B lymphoma cells, A20‐2J. In the present study, we analysed the underlying mechanisms of such up‐regulation using A20‐HL cells derived from A20‐2J cells. Irradiation of A20‐HL cells with 100 Gy enhanced CD80 expression. Incubation of untreated A20‐HL cells with those 100 Gy irradiated induced up‐regulation of CD80 expression. Irradiation of A20‐HL cells also up‐regulated the expression of tumour necrosis factor‐α (TNF‐α) and CD40 ligand (CD40L), and the amount of immunoprecipitable TNF‐α and CD40L in cell lysates. The addition of anti‐TNF‐α or anti‐CD40L monoclonal antibody (mAb) to the incubation of irradiated A20‐HL cells partially inhibited up‐regulation of CD80 expression, and the addition of both antibodies together almost completely inhibited the up‐regulation, suggesting that irradiation up‐regulated the CD80 expression through the induction of TNF‐α and CD40L expression. Irradiation also increased the accumulation of CD80, TNF‐α and CD40L mRNA. n‐tosyl‐l‐phenylalanine chloromethyl ketone (TPCK), a nuclear factor (NF)‐κB inhibitor, markedly decreased irradiation‐induced accumulation of CD80 mRNA and CD80 expression. FK506, a calcineurin inhibitor, and nifedipine, a calcium channel inhibitor, inhibited not only the expression of TNF‐α and CD40L, but also the up‐regulation of CD80 on irradiated A20‐HL cells. These results strongly suggested that irradiation induced TNF‐α and CD40L expression, which then up‐regulated CD80 mRNA and CD80 expression through activation of NF‐κB transcription factor in A20‐HL cells.
Molecular cloning and functional characterization of the pig homologue of integrin‐associated protein (IAP/CD47)
Authors: Shahein Yasser E. A. , De Andrés Damián F. , De La Lastra José M. Pérez 
Published: March 2003

SummaryWe report the cloning of cDNA encoding the pig homologue of human integrin‐associated protein (IAP or CD47). A pig CD47‐specific probe was generated by polymerase chain reaction (PCR) amplification of pig leucocyte cDNA, using primers based on consensus regions among the known sequences of CD47 from different species. Screening of a pig aorta smooth muscle cDNA library identified seven clones, all containing identical sequences. The clones contained an open reading frame (ORF) that encoded an 18 amino acid putative signal peptide, a 122 amino acid sequence consisting of a single extracellular immunoglobulin variable (IgV)‐like domain followed by a 147 amino acid region containing five membrane‐spanning domains and a 16 amino acid cytoplasmic tail. The amino acid sequence of the clones was 73% homologous to human IAP and therefore it was termed pig IAP or CD47. Reverse transcription–polymerase chain reaction (RT–PCR) showed that pig CD47 was expressed in a wide range of tissues and detected different alternatively spliced forms. The monoclonal antibody (mAb) BRIC 126, anti‐human CD47, was shown, by flow cytometry, to stain pig platelets as well as Chinese hamster ovary (CHO) cells transfected with the cDNA encoding pig CD47. Western blot analysis of pig erythocytes and platelets showed a molecular weight (MW) of 43 000–50 000 and of 55 000–65 000, respectively, under non‐reducing conditions. Pig CD47 was stably expressed on CHO cells and shown to bind human thrombospondin (TSP). BRIC126 antibody inhibited the binding of platelets and of CD47‐transfected cells to human TSP and to pig fibrinogen, whereas no effect was observed on control CHO cells.