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Spontaneous Production (spontaneous + production)
Selected AbstractsCytokine production from sputum cells and blood leukocytes in asthmatics according to disease severityALLERGY, Issue 7 2010M. Manise To cite this article: Manise M, Schleich F, Gusbin N, Godinas L, Henket M, Antoine N, Corhay JL, Louis R. Cytokine production from sputum cells and blood leukocytes in asthmatics according to disease severity. Allergy 2010; 65: 889,896. Abstract Background:, Although mild to moderate asthma is known to be Th2 driven, cytokines produced in refractory asthma might not fit the classical Th2 pattern. Methods:, The aim of our study was to assess the cytokine production by sputum and blood cells from 15 refractory asthmatics (American Thoracic Society Criteria) compared to 15 mild untreated and 17 moderate treated asthmatics and 22 healthy subjects. Spontaneous production of interleukin (IL)-4, IL-6, IL-10, interferon-,, and tumor necrosis factor , was measured by immunotrapping after 24 h sputum or blood cell culture. Results:, Moderate and refractory asthmatics were both characterized by a lower production of IL-6 from their airway cells compared to healthy subjects. However, the difference was no longer significant when expressing the results per gram of sputum. No significant difference between the three groups was found regarding other cytokines. As for cytokine production from blood, the three groups of asthmatics exhibited raised production of IL-4 when compared to healthy subjects, and this was true when results were expressed per blood volume or after normalization for total leukocyte cell count. Moderate asthmatics exhibited greater production of IL-10 when compared to refractory asthmatics and healthy subjects when results were normalized for total leukocyte cell count. Conclusions:, Sputum cells from moderate and refractory asthmatics release less IL-6. While the systemic overproduction of IL-4 was observed through the all spectrum of asthma severity, moderate asthmatics exhibited greater systemic IL-10 production compared to refractory asthmatics. [source] Development of antibody to hepatitis B surface antigen after liver transplantation for chronic hepatitis BHEPATOLOGY, Issue 1 2003Chung-Mau Lo Patients with chronic hepatitis B virus (HBV) infection have a defective HBV-specific immune response, and the spontaneous development of antibody against hepatitis B surface antigen (anti-HBs) after liver transplantation has not been observed. We report the spontaneous production of anti-HBs in 21 of 50 (42%) patients receiving lamivudine monoprophylaxis after liver transplantation. Seroconversion to anti-HBs status (>10 mIU/mL) was found at a median of 8 days (range, 1 to 43 days) after transplantation. In each case, serial serum samples showed a >100% increase in antibody titer as compared with that of day 7 after transplantation in the absence of any blood product transfusion. The anti-HBs titer increased to a maximum within 3 months, and the peak titer was <100 mIU/mL in 10 patients, 100 to 1000 mIU/mL in 5 patients, and >1,000 mIU/mL in 6 patients. In 12 patients, anti-HBs disappeared from serum at a median of 201 days (range, 24 to 414 days), whereas the other 9 patients remained positive for anti-HBs at a median of 221 days (range, 94 to 1,025 days) after transplantation. Patients in whom anti-HBs in serum developed had a more rapid clearance of serum hepatitis B surface antigen (HBsAg) (log rank test, P = .011). Using logistic regression analysis, the only predictor of anti-HBs production was an HBV-immune donor (odds ratio, 18.9; 95% confidence interval, 3.2 to 112.4; P = .001). In conclusion, patients who undergo liver transplantation for chronic hepatitis B using lamivudine prophylaxis may develop anti-HBs spontaneously. The antibody is likely to be of donor origin, suggesting the possibility of adoptive immunity transfer through a liver graft. [source] Intracellular and cell-free (infectious) HIV-1 in rectal mucosaJOURNAL OF MEDICAL VIROLOGY, Issue 4 2001Mariantonietta Di Stefano Abstract The intestinal mucosa contains most of the total lymphocyte pool and plays an important role in viral transmission, but only slight attention has been given to the immunological and virological aspects of human immunodeficiency virus-1 (HIV-1) infection at this site. In this study, before initiating or changing antiretroviral therapy, paired blood samples and rectal biopsies (RB) were obtained from 26 consecutive HIV-infected subjects. HIV-1 isolation and biological characterization, DNA, and HIV-1 RNA titration were assessed, as were in vitro tumor necrosis factor-alpha (TNF-,) and interleukin-, (IL-1,) spontaneous production. The rate of HIV-1 isolation from peripheral blood mononuclear cells (PBMCs) and RBs was 75% and 58%, respectively. All RB-derived isolates were nonsyncytium inducing (NSI), independent of the phenotype of blood-derived isolates. Proviral DNA and detectable HIV-1 RNA levels were measured in 100% and 77% of RBs, respectively. A statistical correlation was observed between HIV-1 DNA and HIV-1 RNA levels in rectal mucosa (P,=,0.0075), whereas no correlation was found between these levels in blood samples (P,>,0.05). Antiretroviral treatment did not seem to influence HIV-1 detection in RBs. Higher levels of in vitro proinflammmatory cytokine production were found in the RBs of most infected patients when compared with healthy controls. Therefore, the rectal mucosa is an important HIV-1 reservoir that demonstrates a discordant viral evolution with respect to blood. Both the virus type and the mucosa pathway of immunoactive substances might have important implications for therapeutic decision-making and monitoring and could influence the bidirectional transmission of HIV-1 in mucosal surfaces. J. Med. Virol. 65:637,643, 2001. © 2001 Wiley-Liss, Inc. [source] Cytokine profile in women with preeclampsiaAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2002Yvonne Jonsson Preeclampsia is a severe complication engaging 5,10% of all pregnancies. Immune mechanisms have been suggested in the etiology of this disease. AIM:, To study the systemic spontaneous and fetus-specific cytokine production by peripheral blood mononuclear cells (PBMCs) in women with preeclampsia and normal pregnancies. METHODS:, PBMCs from nine women with preeclampsia and five women with normal pregnancies were stimulated in mixed leukocyte cultures with paternal cells (representing the fetus) and autologous blood lymphocytes. The stimulated and spontaneous production of IL-4, IL-10 and IFN-, were analysed by ELISPOT and IL-12 and IL-13 in cell-culture supernatants by ELISA. Cell-culture supernatants were collected for 2,7 days of incubation. RESULT:, The results are preliminary since analysis of data is going on. We found a trend of decreased IL-10 production in response to paternal cells in preeclamptic women. Data for the other cytokines did not show any differences between groups. CONCLUSION:, The material studied so far is limited and further studies are needed to draw any safe conclusions. [source] Life-cycle toxicity of dibutyltin to the sheepshead minnow (Cyprinodon variegatus) and implications of the ubiquitous tributyltin impurity in test materialAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 9 2003Thomas F. Lytle Abstract Dibutyltin (DBT) is used in the plastics polymerization process as a catalyst in polyvinyl chloride (PVC) products and is the primary degradation product of tributyltin (TBT), an antifoulant in marine paint. DBT and other organotin compounds make their way into the environment through antifoulants, PVC processing plants, and PVC products maintained in water and water-handling systems. A flow-through saltwater life-cycle toxicity test was conducted to determine the chronic effect of DBT to the sheepshead minnow (Cyprinodon variegatus Lacepede), an estuarine species. Embryos were monitored through hatch, maturation, growth, and reproduction in DBT concentrations of 158, 286, 453, 887, and 1510 µg l,1. Progeny were monitored for survival as embryos and fry/juveniles, and growth for 30 days post-isolation. Mean length of parental generation fish was significantly reduced on day 30 at DBT concentrations ,887 µg l,1, setting the lowest observable effect concentration (LOEC) at 887 µg l,1 and the no observable effect concentration (NOEC) at 453 µg l,1. Fecundity, as egg viability, was significantly reduced at the LOEC. Survival of parental and progeny generation embryos and mean length, wet weight and dry weight of progeny generation juveniles were not significantly affected at concentrations ,LOEC. TBT, a toxic impurity in DBT reversibly produced in DBT by the process of comproportionation, was also monitored throughout this study. Comparing measured levels of TBT in this study with levels exerting toxic effects in an earlier TBT life-cycle study with C. variegatus suggests biological responses in this study were likely due to the TBT impurity and not to DBT alone. Results indicate that TBT impurity as low as 0.1% may have a significant influence on the perceived toxicity of DBT and that spontaneous production of TBT in DBT may be the major source of biological toxicity of DBT. Copyright © 2003 John Wiley & Sons, Ltd. [source] Fluoxetine and citalopram exhibit potent antiinflammatory activity in human and murine models of rheumatoid arthritis and inhibit toll-like receptorsARTHRITIS & RHEUMATISM, Issue 3 2010Sandra Sacre Objective Selective serotonin reuptake inhibitors (SSRIs), in addition to their antidepressant effects, have been reported to have antiinflammatory effects. The aim of this study was to assess the antiarthritic potential of 2 SSRIs, fluoxetine and citalopram, in murine collagen-induced arthritis (CIA) and in a human ex vivo disease model of rheumatoid arthritis (RA). Methods Following therapeutic administration of SSRIs, paw swelling was assessed and clinical scores were determined daily in DBA/1 mice with CIA. Joint architecture was examined histologically at the end of the treatment period. Cultures of human RA synovial membranes were treated with SSRIs, and cytokine production was measured. Toll-like receptor (TLR) function was examined in murine and human macrophages, human B cells, and human fibroblast-like synovial cells treated with SSRIs. Results Both SSRIs significantly inhibited disease progression in mice with CIA, with fluoxetine showing the greatest degree of efficacy at the clinical and histologic levels. In addition, both drugs significantly inhibited the spontaneous production of tumor necrosis factor, interleukin-6, and interferon-,,inducible protein 10 in human RA synovial membrane cultures. Fluoxetine and citalopram treatment also inhibited the signaling of TLRs 3, 7, 8, and 9, providing a potential mechanism for their antiinflammatory action. Conclusion Fluoxetine and citalopram treatment selectively inhibit endosomal TLR signaling, ameliorate disease in CIA, and suppress inflammatory cytokine production in human RA tissue. These data highlight the antiarthritic potential of the SSRI drug family and provide further evidence of the involvement of TLRs in the pathogenesis of RA. The SSRIs may provide a template for potential antiarthritic drug development. [source] Modulation of peripheral B cell tolerance by CD72 in a murine modelARTHRITIS & RHEUMATISM, Issue 10 2008Daniel Hsieh-Hsin Li Objective B cells play a dominant role in the pathogenesis of several autoimmune diseases, including systemic lupus erythematosus. It is not well understood how B cell signaling contributes to autoantibody production. The goal of this study was to elucidate the role of CD72 in modulating B cell receptor (BCR),mediated tolerogenic signaling and peripheral B cell tolerance. Methods A mouse model utilizing hen egg lysozyme (HEL) "anergic" B cells was studied. CD72-deficient mice carrying the BCR-specific IgHEL and/or soluble HEL (sHEL) transgenes were generated by breeding IgHEL -transgenic MD4 mice and/or sHEL -transgenic ML5 mice with congenic, CD72-deficient C57BL/6J mice. Normal and anergic B cells were isolated for analyses of B cell signaling. Aged wild-type and CD72-deficient mice were also examined for autoimmune phenomena. Results In the absence of CD72, anergic B cells inappropriately proliferated and survived in response to stimulation with self antigen. Biochemical analyses indicated that in anergic B cells, CD72 dominantly down-regulated BCR signaling to limit the antigen-induced elevation in [Ca2+]i and the activation of NFATc1, NF-,B, MAPK, and Akt. Mechanistically, CD72 was associated with, and regulated, the molecular adaptor Cbl-b in anergic B cells, suggesting that Cbl-b may play a role in mediating the negative effects of CD72 on BCR signaling. Moreover, in aged CD72-deficient mice, spontaneous production of antinuclear and anti,double-stranded DNA autoantibodies and features of lupus-like autoimmune disease were observed. Conclusion CD72 is required to maintain B cell anergy and functions as a regulator of peripheral B cell tolerance. Thus, altered CD72 expression may play a role during the development of systemic lupus erythematosus. [source] Cytokine Induction in Patients Undergoing Regular Online Hemodiafiltration TreatmentARTIFICIAL ORGANS, Issue 7 2000Lajos Vaslaki Abstract: End-stage renal disease (ESRD) patients are known to suffer from chronic inflammation as the result of an ongoing subacute cytokine induction, which may contribute considerably to dialysis-related, long-term morbidity and mortality. Preparation of infusate from cytokine-inducing dialysis fluid and its administration in large quantities as well as the use of high-flux membranes bear the risk of aggravating the chronic inflammatory response among online hemodiafiltration (online HDF) patients. In order to assess the inflammatory risk associated with online HDF, we compared the cytokine induction profile of ESRD patients receiving either online HDF or low-flux hemodialysis (low-flux HD). Specifically, we measured spontaneous and lipopolysaccharide (LPS)-stimulated tumor necrosis factor , (TNF,) and interleukin-1 receptor antagonist (IL-1Ra) release during ex vivo incubation of whole blood. Ultrapure dialysis fluid and polysulfone membranes were used for both treatment modalities. LPS-stimulated release of TNF, and IL-1Ra was elevated for both online HDF and low-flux HD patients compared to healthy individuals (TNF,: 2,336 ± 346 and 2,192 ± 398 versus 1,218 ± 224 pg/106 white blood cells [WBC]; IL-1Ra: 2,410 ± 284 and 2,326 ± 186 versus 1,678 ± 219 pg/106 WBC). Likewise, spontaneous production of TNF,, but not IL-1Ra, was higher in online HDF and low-flux HD patients than in normal controls (37 ± 32 and 22 ± 19 versus 0.8 ± 0.3 pg TNF,/106 WBC). There was no difference in spontaneous and LPS-stimulated cytokine release between both dialysis groups. In addition, intradialytic cytokine induction was not significant for either treatment modality as spontaneous and LPS-stimulated cytokine release were not increased postdialysis. These findings indicate that online HDF does not contribute to chronic leukocyte activation and, consequently, does not place ESRD patients at greater risk with respect to inflammatory morbidity and mortality. [source] In vivo IL-10 and TGF-, production by PBMC from long-term kidney transplant recipients with excellent graft function: a possible feedback mechanism participating in immunological stabilityCLINICAL TRANSPLANTATION, Issue 2 2004Josefina Alberú Abstract:, Background:, Interleukin-10 (IL-10) and transforming growth factor-, (TGF-,) are Th2-derived multifunctional cytokines that exhibit potent immunoregulatory and anti-inflammatory properties which might prolong graft survival. The aim of this study was to explore whether spontaneous production of IL-10 and TGF-, by blood mononuclear cells correlates with excellent long-term graft function. Methods:, A cross-sectional study was carried out in 32 kidney transplant recipients, without albuminuria, treated with azathioprine and prednisone. Spontaneous IL-10 and TGF-, were measured by enzyme-linked immunosorbent assay in supernatants from 24 h cultured unstimulated peripheral blood mononuclear cells. Both cytokines were also determined in 10 healthy kidney donors. Results:, There was no correlation between IL-10 or TGF-, with any variable tested, namely age, SCr, histocompatibility, and post-transplant follow-up. In vivo IL-10 production displayed a statistical trend to be higher in transplant recipients than in controls (362.3 ± 465, range 12.5,1929.3 pg/ml, and 189 ± 170, range 4.17,485.7 pg/ml, respectively; p = 0.08), whereas no difference was observed in TGF-, among the same groups (134.7 ± 79.2, range 68,421 pg/ml, and 121.4 ± 25.8, range 75,151 pg/ml, respectively). Interestingly, a statistically significant inverse correlation was observed between IL-10 and TGF-, in kidney transplant recipients (p = 0.03). Conclusions:, The higher IL-10 production observed in long-term kidney transplant recipients supports the notion that this cytokine contributes in decreasing allogenic immune responses and allows prolongation of allograft survival. The balance between TGF-, and IL-10 may be of paramount importance in graft acceptance. [source] Early Child Grammars: Qualitative and Quantitative Analysis of Morphosyntactic ProductionCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 5 2006Géraldine Legendre Abstract This article reports on a series of 5 analyses of spontaneous production of verbal inflection (tense and person,number agreement) by 2-year-olds acquiring French as a native language. A formal analysis of the qualitative and quantitative results is developed using the unique resources of Optimality Theory (OT; Prince & Smolensky, 2004). It is argued that acquisition of morphosyntax proceeds via overlapping grammars (rather than through abrupt changes), which OT formalizes in terms of partial rather than total constraint rankings. Initially, economy of structure constraints take priority over faithfulness constraints that demand faithful expression of a speaker's intent, resulting in child production of tense that is comparable in level to that of child-directed speech. Using the independent Predominant Length of Utterance measure of syntactic development proposed in Vainikka, Legendre, and Todorova (1999), production of agreement is shown first to lag behind tense then to compete with tense at an intermediate stage of development. As the child's development progresses, faithfulness constraints become more dominant, and the overall production of tense and agreement becomes adult-like. [source] | ||||||||||