The effects of BAFF and BAFF-R-Fc fusion protein in immune thrombocytopenia

Blood ◽  
2009 ◽  
Vol 114 (26) ◽  
pp. 5362-5367 ◽  
Author(s):  
Xiao-juan Zhu ◽  
Yan Shi ◽  
Jun Peng ◽  
Cheng-shan Guo ◽  
Ning-ning Shan ◽  
...  
Keyword(s):  
Fusion Protein ◽  
Immune Thrombocytopenia ◽  
Interleukin 4 ◽  
In Vitro Assays ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cd8 Cells ◽  
Promising Therapeutic Approach ◽  
Fc Fusion Protein ◽  
Ifn Γ

Abstract Elevated level of B-cell activating factor (BAFF) has been implicated in the pathogenesis of some autoimmune diseases. Blockade of receptor and ligand binding by decoy receptor has demonstrated a clinical benefit in both oncologic and immunologic diseases. In this report, we have detected plasma BAFF and BAFF mRNA expression in immune thrombocytopenia (ITP) patients by enzyme-linked immunosorbent assay (ELISA) and real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR). The effects of recombinant human BAFF (rhBAFF) and BAFF-R-Fc fusion protein (BR3-Fc) on B cells, T cells, platelets, secretion of interferon γ (IFNγ), and interleukin-4 (IL-4) were measured by flow cytometry and ELISA. Patients with active disease had higher levels of plasma BAFF and BAFF mRNA than patients in remission and controls. In in vitro assays, rhBAFF promoted the survival of CD19+ and CD8+ cells, and increased the apoptosis of platelets and the secretion of IFN-γ. BR3-Fc successfully corrected the effects of rhBAFF on lymphocytes, platelets, and cytokines. These findings suggest that BAFF may play a pathogenic role in ITP by promoting the survival of CD19+ and CD8+ cells, and increasing the apoptosis of platelets and the secretion of IFN-γ. Blockade of BAFF by BR3-Fc might be a promising therapeutic approach for ITP.

scholarly journals Central Role for Interleukin-4 in Regulating Nitric Oxide-Mediated Inhibition of T-Cell Proliferation and Gamma Interferon Production in Schistosomiasis

2002 ◽  
Vol 70 (1) ◽  
pp. 177-184 ◽  
Author(s):  
Elisabeth A. Patton ◽  
Anne C. La Flamme ◽  
Joao A. Pedras-Vasoncelos ◽  
Edward J. Pearce
Keyword(s):  
Nitric Oxide ◽  
T Cell ◽  
Gamma Interferon ◽  
Interleukin 4 ◽  
T Cell Proliferation ◽  
Th2 Response ◽  
Cd8 Cells ◽  
Cell Functions ◽  
Ifn Γ

ABSTRACT Schistosoma mansoni-infected wild-type (WT) mice develop a Th2 response and chronic disease. In contrast, infected interleukin-4 double-deficient (IL-4−/−) mice develop a Th1-like response and an acute, lethal syndrome. Disease severity in these animals correlates with excessive and prolonged production of nitric oxide (NO) associated with enhanced antigen-driven gamma interferon (IFN-γ) production in the absence of IL-4. Strikingly, splenic lymphocytes from infected IL-4−/− mice failed to proliferate as well as those from infected WT mice following stimulation in vitro with antigen or anti-CD3 antibody. Contrary to antigen-driven IFN-γ responses, anti-CD3 antibody stimulation of splenocytes resulted in significantly less IFN-γ being produced by CD8 cells from infected IL-4−/− mice than by those from infected WT mice or normal mice. NO is largely responsible for the impaired T-cell functions in infected IL-4−/− mice, as inhibition of iNOS significantly enhanced proliferation and IFN-γ production.

scholarly journals Up-Regulation of CD40 Ligand and Induction of a Th2 Response in Children Immunized with Pneumococcal Polysaccharide Vaccines

2001 ◽  
Vol 8 (2) ◽  
pp. 233-240 ◽  
Author(s):  
Lily E. Leiva ◽  
Boyd Butler ◽  
James Hempe ◽  
Alejandro P. Ortigas ◽  
Ricardo U. Sorensen
Keyword(s):  
Mrna Expression ◽  
Mononuclear Cells ◽  
Cd40 Ligand ◽  
Interleukin 4 ◽  
Enzyme Linked Immunosorbent Assay ◽  
Th2 Response ◽  
Polysaccharide Antigens ◽  
Ifn Γ ◽  
Antibody Levels

ABSTRACT We wished to determine whether pneumococcal polysaccharide antigens induce mRNA expression of CD40 ligand (CD40L) and Th1 or Th2 cytokines in unimmunized individuals in vitro and whether immunization with the 23-valent pneumococcal polysaccharide vaccine induces changes in CD40L and cytokine mRNA expression. Children with recurrent respiratory infections were studied before and 4 to 6 weeks after receiving the pneumococcal vaccine. One patient who failed to respond to the polysacharide vaccine subsequently received a single dose of the experimental 7-valent pneumococcal conjugate vaccine. Unimmunized healthy adults were included as controls. Quantification of mRNA expression of CD40L, interleukin-4 (IL-4), IL-12p40, and gamma interferon (IFN-γ) was performed by reverse transcription-PCR and enzyme-linked immunosorbent assay (ELISA)-PCR with resting and stimulated peripheral blood mononuclear cells. Serum immunoglobulin G (IgG) anti pneumococcal antibody levels were measured by ELISA. The results showed a significant increase in the expression of mRNAs for CD40L and IL-4, but not IL-12p40 or IFN-γ, in stimulated cultures from unimmunized individuals. CD40L and IL-4 mRNA expression was significantly higher in postimmunization than in preimmunization samples stimulated with the individual pneumococcal serotypes. These results suggest that pneumococcal polysaccharide antigens specifically up-regulate CD40L expression and induce a Th2 response in vitro which parallels the increase in IgG antipneumococcal antibody levels in serum.

scholarly journals Production of a novel heterodimeric two-chain insulin-Fc fusion protein

2020 ◽  
Vol 33 ◽  
Author(s):  
Christine Faust ◽  
Christian Ochs ◽  
Marcus Korn ◽  
Ulrich Werner ◽  
Jennifer Jung ◽  
...  
Keyword(s):  
Fusion Protein ◽  
Fusion Proteins ◽  
Physiological Role ◽  
Peptide Hormone ◽  
In Vitro Assays ◽  
Fusion Partner ◽  
Insulin Analogs ◽  
Fc Fusion Protein ◽  
A Chain

Abstract Insulin is a peptide hormone produced by the pancreas. The physiological role of insulin is the regulation of glucose metabolism. Under certain pathological conditions the insulin levels can be reduced leading to the metabolic disorder diabetes mellitus (DM). For type 1 DM and, dependent on the disease progression for type 2 DM, insulin substitution becomes indispensable. To relieve insulin substitution therapy for patients, novel insulin analogs with pharmacokinetic and pharmacodynamic profiles aiming for long-lasting or fast-acting insulins have been developed. The next step in the evolution of novel insulins should be insulin analogs with a time action profile beyond 1–2 days, preferable up to 1 week. Nowadays, insulin is produced in a recombinant manner. This approach facilitates the design and production of further insulin-analogs or insulin-fusion proteins. The usage of the Fc-domain from immunoglobulin as a fusion partner for therapeutic proteins and peptides is widely used to extend their plasma half-life. Insulin consists of two chains, the A- and B-chain, which are connected by two disulfide-bridges. To produce a novel kind of Fc-fusion protein we have fused the A-chain as well as the B-chain to Fc-fragments containing either ‘knob’ or ‘hole’ mutations. The ‘knob-into-hole’ technique is frequently used to force heterodimerization of the Fc-domain. Using this approach, we were able to produce different variants of two-chain-insulin-Fc-protein (tcI-Fc-protein) variants. The tcI-Fc-fusion variants retained activity as shown in in vitro assays. Finally, prolonged blood glucose lowering activity was demonstrated in normoglycemic rats. Overall, we describe here the production of novel insulin-Fc-fusion proteins with prolonged times of action.

scholarly journals Dichotomy of Cytokine Profiles in Patients and High-Risk Healthy Subjects Exposed to Tuberculosis

1999 ◽  
Vol 67 (11) ◽  
pp. 5597-5603 ◽  
Author(s):  
S. Bhattacharyya ◽  
R. Singla ◽  
A. B. Dey ◽  
H. K. Prasad
Keyword(s):  
T Cells ◽  
High Risk ◽  
Healthy Subjects ◽  
Ex Vivo ◽  
Close Contact ◽  
Interleukin 4 ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mycobacterial Antigen ◽  
Ifn Γ

ABSTRACT To better understand the role of cytokines in susceptible and resistant subjects exposed to Mycobacterium tuberculosisinfection, intracellular gamma interferon (IFN-γ) and interleukin-4 (IL-4) in ex vivo peripheral blood-derived CD4+ T cells were examined by flow cytometry. Of the 37 individuals examined, 20 had clinical evidence of pulmonary tuberculosis and showed acid-fast bacilli in the sputum. Other individuals in close contact with these patients showed no evidence of disease. Patients had a higher number of CD4+ T cells expressing IFN-γ and IL-4 in unstimulated cultures compared to healthy subjects. Despite this, the ratio of IFN-γ+ to IL-4+ CD4+ T cells was similar in both groups. The Th1 response seen in CD4+ T cells in patients was also observed in the overall pattern of IFN-γ and IL-4 detected in control culture supernatants by enzyme-linked immunosorbent assay (ELISA). However, after in vitro stimulation of PBMC with heat-killed M. tuberculosis there was a significant reduction in the percentage of IFN-γ+CD4+ T cells (P < 0.001) in patients. This trend was reflected in the IFN-γ ELISA assay with supernatants derived from stimulated cultures. However, the accumulated levels of IFN-γ were higher than those for IL-4. The reduction of IFN-γ+ CD4+ T cells resulted in the dominance of IL-4+ CD4+ T cells in 13 patients (P < 0.05). The elevated levels of IL-4+CD4+ T cells seen in patients may contribute to the downregulation of IFN-γ expression and the crucial effector function of CD4 T cells, leading to the persistence of disease and the immunopathology characteristically seen in patients. Preliminary data on the indicators of apoptosis in antigen-stimulated cultures in PBMC derived from patients are presented. Of the 17 high-risk healthy individuals examined, 11 differed in that, after mycobacterial-antigen stimulation, there was an enhancement in IFN-γ+CD4+ T cells.

A Summary of the Third Global Interferon-γ Release Assay Symposium

2013 ◽  
Vol 34 (6) ◽  
pp. 619-624 ◽  
Author(s):  
Antonino Catanzaro ◽  
Charles Daley
Keyword(s):  
Immune Response ◽  
Tuberculin Skin Test ◽  
Skin Test ◽  
Interferon Γ ◽  
Enzyme Linked Immunosorbent Assay ◽  
In Vitro Tests ◽  
The Third ◽  
Specific Antigens ◽  
Ifn Γ

Studies over the past several decades have dramatically increased our understanding of the immune response to Mycobacterium tuberculosis infection, and advances in proteomics and genomics have led to a new class of immune-diagnostic tests, termed interferon-γ (IFN-γ) release assays (IGRAs), which appear to obviate many of the problems encountered with the tuberculin skin test (TST). Worldwide, 2 IGRAs are currently commercially available. QuantiFERON-TB Gold In-Tube (Cellestis) is a third-generation product that uses an enzyme-linked immunosorbent assay to measure IFN-γ generated in whole blood stimulated with M. tuberculosis–specific antigens. T-Spot-TB (Oxford Immunotec) employs enzyme-linked immunosorbent spot technology to enumerate the number of purified lymphocytes that respond to M. tuberculosis–specific antigens by producing IFN-γ. These in vitro tests measure the host immune response to M. tuberculosis–specific antigens, which virtually eliminates false-positive cross reactions caused by bacillus Calmette-Guérin vaccination and/or exposure to environmental nontuberculous mycobacteria that plague the interpretation and accuracy of the tuberculin skin test (TST). The high specificity of IGRAs, together with sensitivity commensurate with or better than that of the TST, promises an accurate diagnosis and the ability to focus tuberculosis-control activities on those who are actually infected with M. tuberculosis. The Third Global Symposium was held over a 3-day period and was presented by the University of California, San Diego, Continuing Medical Education department; slides and sound recordings of each presentation are available at http://cme.ucsd.edu/igras/syllabus.html. A moderated discussion is also available at http://cme.ucsd.edu/igrasvideo. This document provides a summary of the key findings of the meeting, specifically focusing on the use of IGRAs in screening healthcare worker populations.

scholarly journals Effect ofTityus serrulatusvenom on cytokine production and the activity of murine macrophages

2002 ◽  
Vol 11 (1) ◽  
pp. 23-31 ◽  
Author(s):  
Vera L. Petricevich
Keyword(s):  
Cytokine Production ◽  
Peritoneal Macrophages ◽  
Interferon Γ ◽  
Enzyme Linked Immunosorbent Assay ◽  
No Production ◽  
Dependent Manner ◽  
Immune Functions ◽  
Macrophage Activity ◽  
Ifn Γ

The purpose of this study was to investigate the effects ofTityus serrulatusvenom (TSV) on murine peritoneal macrophages evaluated in terms of activation. The effects of crude TSV were analysed by detection of cytokines, oxygen intermediate metabolites (H2O2) and nitric oxide (NO) in supernatants of peritoneal macrophages. Several functional bioassays were employed including anin vitromodel for envenomating: cytotoxicity of TSV was assessed using the lyses percentage. Tumor necrosis factor (TNF) activity was assayed by measuring its cytotoxic activity on L-929 cells, and interleukin-6 (IL-6) and interferon-γ (IFN-γ) were assayed by enzyme-linked immunosorbent assay, whereas NO levels were detected by Griess colorimetric reactions in culture supernatant of macrophages incubated with TSV and subsequently exposed to either lipopolysaccharide or IFN-γ. Incubation of macrophages with TSV increased production of IL-6 and IFN-γ in a dose-dependent manner. TNF production was not detected in supernatants treated with TSV at any concentration. The increase in IL-6 secretion was not associated with concentration-dependent cytoxicity of TSV on these cells. These data suggest that the cytotoxicity does not appear to be the main cause of an increased cytokine production by these cells. Although NO is an important effector molecule in macrophage microbicidal activity, the inducing potential of the test compounds for its release was found to be very moderate, ranging from 125 to 800 mM. Interestingly, NO levels of peritoneal macrophages were increased after IFN-γ. Moreover, NO production had an apparent effect on macrophage activity. The results obtained here also shown that the TSV induces an important elevation in H2O2release. These results combined with NO production suggest that TSV possesses significant immunomodulatory activities capable of stimulating immune functionsin vitro.

scholarly journals Desnutrição neonatal e produção de IFN-γ IL-12 e IL-10 por macrófagos/linfócitos: estudo da infecção celular, in vitro, por Staphylococcus aureus meticilina sensível e meticilina resistente

2012 ◽  
Vol 25 (5) ◽  
pp. 607-619 ◽  
Author(s):  
Thacianna Barreto da Costa ◽  
Natália Gomes de Morais ◽  
Thays Miranda de Almeida ◽  
Maiara Santos Severo ◽  
Célia Maria Machado Barbosa de Castro
Keyword(s):  
Staphylococcus Aureus ◽  
Immunosorbent Assay ◽  
Enzyme Linked Immunosorbent Assay ◽  
Ifn Γ

OBJETIVO: Avaliar a influência da desnutrição neonatal sobre a produção de Interferon gama, Interleucina-12 e Interleucina-10 em cultura de macrófagos alveolares e linfócitos infectados, in vitro, com Staphylococcus aureus sensível/resistente à meticilina. MÉTODOS: Ratos machos Wistar foram amamentados por mães cuja dieta, durante a lactação, continha 17% de proteína no grupo nutrido e 8% no grupo desnutrido. Após desmame, ambos os grupos receberam a dieta normoproteica. Os macrófagos foram obtidos após traqueostomia, através da coleta do lavado broncoalveolar. Para obtenção dos linfócitos, foi realizado o procedimento cirúrgico de punção cardíaca. Após o isolamento dos diferentes tipos celulares, procedeuse à realização dos estímulos com as cepas de estudo. A dosagem das citocinas foi realizada pelo método de Enzyme-Linked Immunosorbent Assay, a partir de amostras coletadas do sobrenadante das culturas após 24 horas de incubação. RESULTADOS: A desnutrição acarretou diminuição do crescimento ponderal, redução na produção de Interferon gama em cultura de macrófagos alveolares e linfócitos e diminuição na produção de Interleucina-12 em cultura de macrófagos alveolares. Apenas a produção de Interferon gama e Interleucina-10 em cultura de macrófagos alveolares apresentou diferença entre as cepas analisadas, em ambos os grupos estudados. CONCLUSÃO: O modelo de desnutrição neonatal produziu sequela no peso corporal e reduziu a produção de citocinas próinflamatórias (Interleucina-12 e Interferon gama), indicando que esse modelo de desnutrição pode comprometer a resolução de um processo infeccioso. A cepa de Staphylococcus aureus resistente à meticilina estimulou uma maior produção de Interferon gama e Interleucina-10 por macrófagos alveolares, o que sugeriu estimulação imunológica mais intensa, por essa cepa, nesse tipo celular especificamente.

scholarly journals An Ex Vivo Study of T Lymphocytes Recovered from the Lungs of I/St Mice Infected with and Susceptible toMycobacterium tuberculosis

1998 ◽  
Vol 66 (10) ◽  
pp. 4981-4988 ◽  
Author(s):  
Irina Lyadova ◽  
Vladimir Yeremeev ◽  
Konstantin Majorov ◽  
Boris Nikonenko ◽  
Sergei Khaidukov ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
Antimycobacterial Activity ◽  
Enzymatic Digestion ◽  
Interleukin 4 ◽  
T Cell Clones ◽  
Cell Clones ◽  
Ifn Γ

ABSTRACT I/St mice, previously characterized as susceptible toMycobacterium tuberculosis H37Rv, were given 103 or 105 CFU intravenously. At two time points postinoculation, the cell suspensions that resulted from enzymatic digestion of lungs were enumerated and further characterized phenotypically and functionally. Regarding the T-cell populations recovered at 2 and 5 weeks postinfection, two main results were obtained: (i) the population of CD44− CD45RB+cells disappeared within 2 weeks postinfection, while the number of CD44+ CD45RB−/low cells slowly increased between weeks 2 and 5; (ii) when cocultured with irradiated syngeneic splenocytes, these lung T cells proliferated in the presence of H37Rv sonicate. Using H37Rv sonicate and irradiated syngeneic splenocytes to reactivate lung T cells, we selected five CD3+CD4+ CD8− T-cell clones. In addition to the H37Rv sonicate, the five clones react to both a short-term culture filtrate and an affinity-purified 15- to 18-kDa mycobacterial molecule as assessed by the proliferative assay. However, there was a clear difference between T-cell clones with respect to cytokine (gamma interferon [IFN-γ] and interleukin-4 [IL-4] and IL-10) profiles: besides one Th1-like (IFN-γ+ IL-4−) clone and one Th0-like (IFN-γ+ IL-4+IL-10+) clone, three clones produced predominantly IL-10, with only marginal or no IL-4 and IFN-γ responses. Inhibition of mycobacterial growth by macrophages in the presence of T cells was studied in a coculture in vitro system. It was found that the capacity to enhance antimycobacterial activity of macrophages fully correlated with INF-γ production by individual T-cell clones following genetically restricted recognition of infected macrophages. The possible functional significance of cytokine diversity among T-cell clones is discussed.

scholarly journals Spontaneous secretion of interferon γ and interleukin 4 by human intraepithelial and lamina propria gut lymphocytes

Gut ◽  
1998 ◽  
Vol 42 (5) ◽  
pp. 643-649 ◽  
Author(s):  
M Carol ◽  
A Lambrechts ◽  
A Van Gossum ◽  
M Libin ◽  
M Goldman ◽  
...  
Keyword(s):  
Lamina Propria ◽  
Intestinal Mucosa ◽  
Mononuclear Cells ◽  
Critical Role ◽  
Gastrointestinal Diseases ◽  
Interferon Γ ◽  
Interleukin 4 ◽  
Peripheral Blood Mononuclear ◽  
Ifn Γ

Background—Cytokines secreted by intestinal T lymphocytes probably play a critical role in regulation of the gut associated immune responses.Aims—To quantify interferon γ (IFN-γ) and interleukin 4 (IL-4) secreting cells (SC) among human intraepithelial (IEL) and lamina propria (LPL) lymphocytes from the duodenum and right colon in non-pathological situations and in the absence of in vitro stimulation.Patients—Duodenal and right colonic biopsy specimens were obtained from patients with no inflammation of the intestinal mucosa.Methods—Intraepithelial and lamina propria cell suspensions were assayed for numbers of cells spontaneously secreting IFN-γ and IL-4 by a two site reverse enzyme linked immunospot technique (ELISPOT).Results—The relatively high proportion of duodenal lymphocytes spontaneously secreting IFN-γ (IEL 3.6%; LPL 1.9%) and IL-4 (IEL 1.3%; LPL 0.7%) contrasted with the very low numbers of spontaneously IFN-γ SC and the absence of spontaneously IL-4 SC among peripheral blood mononuclear cells. In the basal state, both IFN-γ and IL-4 were mainly produced by CD4+ cells. Within the colon, only 0.2% of IEL and LPL secreted IFN-γ in the basal state, and 0.1% secreted IL-4.Conclusions—Compared with peripheral lymphocytes substantial proportions of intestinal epithelial and lamina propria lymphocytes spontaneously secrete IFN-γ and/or IL-4. These cytokines are probably involved in the normal homoeostasis of the human intestinal mucosa. Disturbances in their secretion could play a role in the pathogenesis of gastrointestinal diseases.

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