bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanisms of the in vitro fungicidal effects of human neutrophils against Penicillium marneffei induced by granulocyte-macrophage colony-stimulating factor (GM-CSF)
Authors: Kudeken N , Kawakami K , Saito A 
Published: March 2003

SUMMARY
We examined the in vitro fungicidal activity of human neutrophils against conidia and yeast cells of Penicillium marneffei. Neutrophils showed a small but significant anti-fungal effect against the yeast form of P. marneffei. Treatment of neutrophils with GM-CSF significantly augmented their anti-fungal activity. In contrast, the conidia form resisted killing even by stimulated neutrophils. Neutrophil fungicidal effect was not inhibited by superoxide dismutase (SOD), while the same treatment significantly suppressed the killing of Candida albicans by GM-CSF-stimulated neutrophils. For effective killing of P. marneffei yeast cells by GM-CSF-stimulated neutrophils, direct contact between the two was essential; interference in such interaction by separation using a 0·45-μm-pored membrane prevented such an effect. Addition of colchicine attenuated GM-CSF-stimulated neutrophil fungicidal activity in a dose-dependent manner. This effect did not appear to be mediated by interference with neutrophil mobility toward yeast cells, because similar results were obtained when the cultures were set in round-bottomed wells which facilitate their direct contact. Finally, granular extracts derived from unstimulated neutrophils significantly suppressed the growth of microorganisms. Pretreatment of neutrophils with GM-CSF markedly enhanced this effect. The fungicidal activity of granular lysates was strongly, but not completely, reduced by heat treatment. Considered together, our results indicate that GM-CSF-stimulated neutrophils killed the yeast form of P. marneffei present in close proximity, probably in a superoxide anion-independent mechanism, but through exocytosis of granular enzymes which were largely heat-labile.
The development of post-kala-azar dermal leishmaniasis (PKDL) is associated with acquisition ofLeishmaniareactivity by peripheral blood mononuclear cells (PBMC)
Authors: Gasim S , Elhassan A M , Kharazmi A , Khalil E A G , Ismail A , Theander T G 
Published: March 2003

SUMMARYPKDL develops in about 50% of Sudanese patients treated for visceral leishmaniasis (kala-azar). Patients with kala-azar were entered into this study and followed for a period of up to 2 years. During follow up 12 patients developed PKDL and eight did not. Proliferative responses and cytokine production to Leishmania donovani and control antigens were measured in vitro using PBMC isolated at the time of diagnosis of kala-azar, after treatment of visceral leishmaniasis, during follow up, and at the time of diagnosis of PKDL. Proliferative responses and interferon-gamma (IFN-γ) production were low at diagnosis and increased after treatment of kala-azar in both patients who developed (group 1) and those who did not develop PKDL later (group 2). In group 1, development of PKDL was always associated by an increased PBMC response to Leishmania antigen in proliferation and IFN-γ production assays. There were no differences in Leishmania antigen-induced production of IL-4, IL-5 and IL-10 between or within the two groups. We have previously shown that Leishmania parasites spread to the skin during visceral leishmaniasis and proposed that PKDL was the result of an immunological attack on parasites, which have survived in the skin despite the drug treatment. The finding that PKDL develops after treatment of kala-azar as Leishmania-reactive T cells start to circulate in peripheral blood in sufficient numbers to be detected in in vitro assays supports this hypothesis.
Expression of HLA-DR, costimulatory molecules B7-1, B7-2, intercellular adhesion molecule-1 (ICAM-1) and Fas ligand (FasL) on gastric epithelial cells inHelicobacter pylorigastritis; influence ofH. pylorieradication
Authors: Archimandritis A , Sougioultzis S , Foukas P G , Tzivras M , Davaris P , Moutsopoulos H M 
Published: March 2003

SUMMARYThere is evidence that Helicobacter pylori infection up-regulates the expression of HLA class II molecules by gastric epithelial cells (GEC). In this study we evaluated whether GEC are capable of expression of costimulatory molecules in H. pylori gastritis. The expression of FasL by GEC, before and after eradication of H. pylori, was also studied. Thirty patients (23 men) aged 27–81 years (53·67 ± 13·99 years (mean ± s.d.)) with dyspepsia were studied. Upper gastrointestinal endoscopy was performed and six biopsies were obtained (antrum, n= 3; corpus, n= 3) for Campylobacter-Like Organisms (CLO) test and histology; 23 (16 men) were H. pylori+ and seven (all men) were H. pylori− by both methods and served as controls. Helicobacter pylori eradication therapy was given to H. pylori+ patients and all patients were re-endoscoped after 116 ± 9 days. Formalin-fixed paraffin-embedded tissue sections were stained by the ABC immunoalkaline phosphatase method. In H. pylori gastritis HLA-DR was expressed and correlated with disease activity (P &lt; 0·01). No HLA-DR was observed in controls. In H. pylori-eradicated patients significant decrease of HLA-DR was found (antrum, P &lt; 0·001). ICAM-1 was expressed by GEC in 80% of H. pylori+ patients; ICAM-1 expression did not correlate with gastritis parameters and decreased significantly after eradication (antrum, P &lt; 0·01). B7-1 and B7-2 were expressed on H. pylori+ samples and their expression decreased after eradication, albeit not significantly. Weak epithelial expression of both B7 molecules was observed in all the controls. FasL was steadily expressed by GEC in both H. pylori+ and H. pylori− patients and remained almost unchanged after eradication. These findings suggest that GEC may acquire antigen-presenting cell properties in H. pylori infection through de novo expression of HLA-DR and costimulatory molecules. This seems to be attenuated after eradication and resolution of mucosal inflammation. The same cells exhibit the capacity to control the inflammatory process, probably by inducing apoptotic cell death to Fas-bearing infiltrating lymphocytes.
Prednisolone inhibits cytokine-induced adhesive and cytotoxic interactions between endothelial cells and neutrophilsin vitro
Authors: Heimbürger M , Lärfars G , Bratt J 
Published: March 2003

SUMMARYWe assessed whether prednisolone influenced the ability of human polymorphonuclear neutrophils (PMN) to adhere to and cause lysis of human umbilical vein endothelial cells (HUVEC) in vitro (as measured by the release of 51Cr). Pretreatment of the endothelium with IL-1β or tumour necrosis factor-alpha (TNF-α) caused prominent endothelial E-selectin expression and endothelial hyperadhesiveness for neutrophils, as well as PMN-mediated cytotoxicity. All these processes were dose-dependently reduced when prednisolone was added to the assay system. This protective effect remained when HUVEC alone were pretreated with the drug prior to washing and cytokine activation. Likewise, when HUVEC cytotoxicity was induced by the nitric oxide (NO) donor S-nitroso-acetyl-penicillamine (SNAP), prednisolone reduced cell injury significantly. In contrast, prednisolone did not interfere with signalling systems between TNF-α-stimulated HUVEC and quiescent PMN such as IL-8 generation and release of cytosolic Ca2 + in the PMN. Thus, in this in vitro model of vasculitis, prednisolone dose-dependently reduced cytokine-induced E-selectin expression and HUVEC hyperadhesiveness for neutrophils, as well as reducing neutrophil-dependent cytotoxicity against HUVEC via NO-dependent steps.
Change in perforin-positive peripheral blood lymphocyte (PBL) subpopulations following exercise
Authors: Staats R , Balkow S , Sorichter S , Northoff H , Matthys H , Luttmann W , Berg A , Virchow J C 
Published: March 2003

SUMMARYPerforin, one of the cytotoxic proteins of the immune system, plays a prominent role in protection against viral and bacterial infections. We investigated its expression in PBL and their CD3+, CD4+, CD8+ and CD16+ and/or CD56+ subpopulations in endurance athletes before and after a triathlon. Lymphocyte subpopulations were analysed by flow cytometry following separation of peripheral blood mononuclear cells and staining with antibodies against specific membrane antigens and intracellular perforin. The number of total lymphocytes decreased from 2.1 × 103/μl before the triathlon to 1.0 × 103/μl 1 h after the triathlon (P &lt; 0.01). Interestingly, there was already a significant spontaneous decline in the percentage of CD3+/perforin+, and in CD8+/perforin+ cells, in the week proceeding the triathlon, when subjects were instructed to refrain from strenuous exercise training. The percentage of CD3+/perforin+, CD8+/perforin+ and CD16+ and/or CD56+/perforin+ cells in each lymphocyte subpopulation decreased 1 h after exercise even further from 14.3% to 5.8% (P &lt; 0.05), 18.5% to 6.5% (P &lt; 0.05) and 77.3% to 67.3%, respectively. However, at 18 h and 48 h after exercise the percentage of perforin-expressing CD3+, CD8+ and CD16+/56+ cells increased again towards baseline levels. Compared with normal controls, baseline perforin co-expression in CD3+ and CD8+ lymphocytes was significantly higher in trained athletes. From our data we conclude that trained athletes have an increased percentage of perforin+ PBL and that following exercise the percentage of perforin+ and therefore potentially cytotoxic lymphocytes transiently decreases in peripheral blood.
T cell lines specific for a synthetic Heymann nephritis peptide derived from the receptor-associated protein
Authors: Wu H , Zhang G Y , Knight J F 
Published: March 2003

SUMMARYPathogenic antigens involved in the induction of Heymann nephritis (HN), an experimental rat model of human membranous nephritis, have been identified in megalin (gp330) and the receptor-associated protein (RAP) [1,2]. A pathogenic epitope has been identified in RAP (amino acid 1–86) that plays a significant role in the formation of immune deposits in glomeruli in HN. A synthetic peptide (P31−53) derived from RAP1−86 contains a pathogenic epitope recognized by antibodies eluted from glomerular immune deposits and includes two putative RT-1B1 MHC class II-binding motifs. We have investigated whether RAP P31−53 can be recognized by T cells. Five peptide-specific T cell lines were generated from regional lymph node (LN) T cells from Lewis rats immunized with P31−53. The T cell lines were characterized by using a T cell proliferation assay for their specificity, FACS and MHC restriction assay for the phenotype, reverse transcription-polymerase chain reaction for TCR Vβ repertoire and cytokine expression, and cloning and sequencing for the analysis of the CDR3 sequence of TCR. The helper function of the T cell line was confirmed by autoantibody production in vitro. In this study, we clearly identify that the synthetic pathogenic peptide P31−53 contains a T cell epitope recognized by CD4+ Th2 cells in Lewis rats. This recognition was restricted by MHC class II RT1.B1. These CD4+ Th2 cells were able to promote B cells to produce specific antibodies and used a restricted set of TCR Vβ genes with preferential usage of Vβ18. A charged amino acid motif at the CDR3 region of predominant TCR Vβ subfamilies may contribute to the specific ability of these cells to recognize the immunogenic T cell epitope within RAP peptide P31−53.
Predominant type-2 response in infants with respiratory syncytial virus (RSV) infection demonstrated by cytokine flow cytometry
Authors: Bendelja K , Gagro A , Baće A , Lokar-Kolbas R , Kršulović-Hrešić V , Drazenović V , Mlinaric-Galinović G , Rabatić S 
Published: March 2003

SUMMARYAcute RSV infection in infancy may produce some asthma-like symptoms and may be followed by a recurrent wheeze later in childhood. It has been proposed that RSV infection stimulates type-2 cytokine responses, resembling those found in atopy and asthma. Peripheral blood cells were obtained from RSV-infected infants (n = 30) and healthy controls (n = 10). After in vitro restimulation of the cells, intracellular IL-4 and interferon-gamma (IFN-γ) were measured by flow cytometry. The cells from RSV-infected infants produced more IL-4 and less IFN-γ than those from healthy controls. IL-4 production was more frequent in CD8 than in CD4 cells, and the bias toward IL-4 production was greatest in infants with mild infections, whereas IFN-γ production increased with disease severity. Our conclusions are that RSV infection is associated with IL-4 production in peripheral T cells, and that peripheral blood in infants with severe disease may be depleted of cytokine-producing cells.
Deficiency in circulating natural killer (NK) cell subsets in common variable immunodeficiency and X-linked agammaglobulinaemia
Authors: Aspalter R M , Sewell W A C , Dolman K , Farrant J , Webster A D B 
Published: March 2003

SUMMARYAbsolute and relative NK cell numbers were determined in peripheral whole blood by flow cytometry in patients with common variable immunodeficiency (CVID) (n = 55) and X-linked agammaglobulinaemia (XLA) (n = 19) on regular immunoglobulin (IVIG) therapy. Absolute CD3−CD16+ NK cell numbers were significantly reduced in CVID patients (median 108/μl, range 23–815), compared with normal subjects (n = 60) (289/μl, range 56–640, P &lt; 0·001). Total lymphocyte concentrations were significantly lower in CVID (median 1587/μl, range 523–7519) compared with normal subjects (median 2019/μl, range 1124–3149, P = 0·004), with the percentage of NK cells also being significantly decreased (median 7·5%, range 3·0–33·0%, compared with 14·2%, range 2·6–30·8%, P &lt; 0·001). In XLA, absolute NK cell numbers (median 140/μl, range 32–551, P &lt; 0·001) but not relative numbers were significantly reduced compared with normal controls. We excluded the possibility that IVIG interferes with in vitro binding of CD16 MoAbs. Further analysis of NK cell subsets showed a deficiency of both CD16+ and CD56+ cells in CVID, most marked in the CD3−CD8dim subpopulation, which may be due to increased homing of these cells to the gut. Serial studies on a small number of patients suggest that IVIG therapy has no short-term effect on NK cells, although we cannot exclude an effect with prolonged use. Although there are no obvious clinical effects of the NK depletion in CVID and XLA, this may be a factor in their predisposition to cancer.
Kinetic studies of the production of nitric oxide (NO) and tumour necrosis factor-alpha (TNF-α) in macrophages stimulated withBurkholderia pseudomalleiendotoxin
Authors: Utaisincharoen P , Tangthawornchaikul N , Kespichayawattana W , Anuntagool N , Chaisuriya P , Sirisinha S 
Published: March 2003

SUMMARYThe mechanism by which Burkholderia pseudomallei survives in macrophages is not clearly understood. In this study, we demonstrated that the mouse macrophage cell line (RAW 264.7) treated with lipopolysaccharide (LPS) from B. pseudomallei (BP-LPS) produced significantly less NO and TNF-α compared with those stimulated with the LPS from Escherichia coli and Salmonella typhi. The time required for the BP-LPS to trigger substantial NO and TNF-α release was at least 30 min, compared with &lt; 5 min for the E. coli-LPS. A time course study of inducible nitric oxide synthase (iNOS) protein expression also indicated that the time required for macrophages stimulated with the BP-LPS to up-regulate iNOS was longer. The longer time lag for the BP-LPS to activate macrophages was probably due to the delay in up-regulation of iNOS and TNF-α mRNA transcription. These results indirectly suggest that the delay of the mediators' production may be due to a reduced rate of signal transduction initiated by the interaction of BP-LPS with the macrophage cell surface. The use of MoAb to phosphorylated p38 in a Western blot analysis provided data compatible with the notion that the maximum level of phosphorylated p38 from the cells activated with BP-LPS was attained at a slower rate. These results suggest that the unique structure of BP-LPS exhibits a property which may interfere with macrophage cell activation.
Effect of adhesion on inducible nitric oxide synthase (iNOS) production in purified human neutrophils
Authors: Webb J L , Polak J M , Evans T J 
Published: March 2003

SUMMARYThe production of nitric oxide (NO) within neutrophils is an important element of the innate immune response. We have previously shown that cytokines (IL-1α, tumour necrosis factor-alpha and interferon-gamma) induce human neutrophils in buffy coat preparations to produce iNOS. In order to define better the exact requirements for iNOS production within human neutrophils, we have studied the conditions needed for the production of iNOS in purified neutrophils. In contrast to buffy coat preparations, purified neutrophils in suspension did not produce an increase in iNOS following addition of cytokines. However, when purified neutrophils were allowed to adhere to glass surfaces either uncoated or coated with fetal calf serum (FCS), plasma, fibronectin or laminin, there was an increase in the percentage of iNOS-positive cells. The addition of cytokines during adhesion of these cells increased this proportion further. This was most marked for glass alone and FCS-coated glass on which the proportion of iNOS-positive cells increased to 22·7% and 35·5%, respectively, a significant increase compared with cytokine-treated neutrophils in suspension. Neither transmigration through activated endothelial monolayers nor the addition of soluble intercellular adhesion molecule-1 to purified neutrophil suspensions increased the percentage of iNOS-positive cells following cytokine stimulation. Adhesion of neutrophils to surfaces coated with IgG or complement also failed to increase cytokine-induced iNOS production. We conclude that iNOS production in human neutrophils requires not only cytokine stimulation, but also additional stimuli from adhesion to a surface.
Thiols decrease cytokine levels and down-regulate the expression of CD30 on human allergen-specific T helper (Th) 0 and Th2 cells
Authors: Bengtsson Å , Lundberg M , Avila-Cariño J , Jacobsson G , Holmgren A , Scheynius A 
Published: March 2003

SummaryThe thiol antioxidant N-acetyl- l-cysteine (NAC), known as a precursor of glutathione (GSH), is used in AIDS treatment trials, as a chemoprotectant in cancer chemotherapy and in treatment of chronic bronchitis. In vitro, GSH and NAC are known to enhance T cell proliferation, production of IL-2 and up-regulation of the IL-2 receptor. The 120-kD CD30 surface antigen belongs to the tumour necrosis factor (TNF) receptor superfamily. It is expressed by activated T helper (Th) cells and its expression is sustained in Th2 cells. We have analysed the effect of GSH and NAC on the cytokine profile and CD30 expression on human allergen-specific T cell clones (TCC). TCC were stimulated with anti-CD3 antibodies in the presence of different concentrations of GSH and NAC. Both thiols caused a dose dependent down-regulation of IL-4, IL-5 and IFN-γ levels in Th0 and Th2 clones, with the most pronounced decrease of IL-4. Furthermore, they down-regulated the surface expression of CD30, and the levels of soluble CD30 (sCD30) in the culture supernatants were decreased. In contrast, the surface expression of CD28 or CD40 ligand (CD40L) was not significantly changed after treatment with 20 m m NAC. These results indicate that GSH and NAC favour a Th1 response by a preferential down-regulation of IL-4. In addition, the expression of CD30 was down regulated by GSH and NAC, suggesting that CD30 expression is dependent on IL-4, or modified by NAC. In the likely event that CD30 and its soluble counterpart prove to contribute to the pathogenesis in Th2 related diseases such as allergy, NAC may be considered as a future therapeutic agent in the treatment of these diseases.
Intradermal skin test with diabetes specific antigens in patients with type 1 diabetes
Authors: Crinò A , Cavallo M G , Corbi S , Mesturino C A , Ferrazzoli F , Coppolino G , Bizzarri C , Cervoni M , Monetini L , Pozzilli P ,   THE IMDIAB GROUP
Published: March 2003

SummaryCell mediated immune response in vitro to a number of antigens has been reported in patients with Type 1 diabetes. The aim of the present study was to develop an in vivo intradermal (delayed type hypersensitivity) skin test using antigens known to be recognized by lymphocytes of patients with Type 1 diabetes and to compare, where possible, the in vivo response to the in vitro T cell proliferation to the same antigens.The skin test was performed in the following group of patients: 55 with recent onset Type 1 diabetes; 16 patients with Type 1 diabetes of longer duration; 10 patients with autoimmune thyroid disease and 20 patients with Latent Autoimmune Diabetes in Adults (LADA). Type 1 diabetes specific antigens for the skin test included glutamic acid decarboxilase (GAD65), insulin and beta casein, whereas diabetes non specific antigens included tetanus toxoid, diphteria, proteus, tubercolin, streptococcus, and glycerol as control. A multitest device consisting of heads delivering intradermally 10 µl of solution containing the antigens was applied to the forearms; the specific antigens were injected in one forearm whereas the non specific antigens were injected in the other forearm. Reading of the reaction, which was considered positive in the presence of a nodule of 2 mm diameter was performed 48 h after the multitest application. The in vitro T cell response to diabetes specific antigens used in the multitest was studied using conventional proliferation assays in patients with recent onset Type 1 diabetes and in age matched normal subjects.Only recent onset Type 1 diabetes patients showed an in vivo positive response to GAD65, such response being detectable in 10 patients (18%). Two patients reacted also to beta casein and insulin, all other patient groups resulted negative but 2 patients with longer duration of Type 1 diabetes. There was no apparent link between the in vivo skin test and in vitro T cell proliferation to GAD65.We conclude that in vivo cell mediated immune reaction to GAD65, insulin and beta casein can be visualized in a minority of patients with recent onset Type 1 diabetes. Further studies are required to determine specificity and whether altering the dose can improve the sensitivity of the test.
Prophylactic and therapeutic effects of a humanized monoclonal antibody against the IL-2 receptor (DACLIZUMAB) on collagen-induced arthritis (CIA) in rhesus monkeys
Authors: Brok H P M , Tekoppele J M , Hakimi J , Kerwin J A , Nijenhuis E M , De Groot C W , Bontrop R E , ‘t Hart B A 
Published: March 2003

SUMMARYCIA in the rhesus monkey is an autoimmune-based polyarthritis with inflammation and erosion of synovial joints that shares various features with human rheumatoid arthritis (RA). The close phylogenetic relationship between man and rhesus monkey makes the model very suitable for preclinical safety and efficacy testing of new therapeutics with exclusive reactivity in primates. In this study we have investigated the prophylactic and therapeutic effects of a humanized monoclonal antibody (Daclizumab) against the α-chain of the IL-2 receptor (CD25). When Daclizumab treatment was started well after immunization but before the expected onset of CIA a significant reduction of joint-inflammation and joint-erosion was observed. A therapeutic treatment, initiated as soon as the first clinical signs of CIA were observed, proved also effective since joint-degradation was abrogated. The results of this study indicate that Daclizumab has clinical potential for the treatment of RA during periods of active inflammation and suppression of the destruction of the joint tissues.