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Biomedical subjects

M Goldman

Publications and source records attributed to M Goldman.

At least 19 recordsLinked to original sources

The interleukin-12 family: new players in transplantation immunity?

Since several years ago, interleukin (IL)-12 is known to be responsible for the differentiation of naive CD4+ T cells into type 1 helper T cells producing interferon-gamma. Recently, two other cytokines of the IL-12 family, IL-23 and IL-27, were shown to play key roles in experimental autoimmune disorders mediated by Th17 cells, a novel pro-inflammatory CD4+ T-cell subset secreting IL-17. As our knowledge of IL-12 family members is rapidly growing and changing, it will be important to specify their involvement in the induction and regulation of allograft rejection in animal models as well as in clinical settings. Herein, we review key features of cytokines belonging to the IL-12 family and discuss their potential relevance to transplantation immunity.

Animals↗

Translational mini-review series on Toll-like receptors: Toll-like receptor ligands as novel pharmaceuticals for allergic disorders.

Characterization of the Toll-like receptor (TLR) family and associated signalling pathways provides a key molecular basis for our understanding of the relationship between exposure to microbial products and susceptibility to immune-mediated disorders. Indeed, ligation of TLR controls innate and adaptive immune responses by inducing synthesis of pro- as well as anti-inflammatory cytokines and activation of effector as well as regulatory lymphocytes. TLRs are therefore considered as major targets for the development of vaccine adjuvants, but also of new immunotherapies. Herein, we review the potential of TLR ligands as a novel class of pharmaceuticals for the prevention or treatment of allergic disorders.

Anti-Allergic Agents↗

N-Acetylcysteine derivative inhibits procoagulant activity of human islet cells.

AIMS/HYPOTHESIS: The early loss of beta cells after islet cell transplantation has been attributed in part to blood coagulation at the implant site. Tissue factor expressed by beta cells and contaminating duct cells is considered to activate this process. Here, we investigated the ability of N-acetyl-L-cysteine to suppress the in vitro procoagulant activity of duct cells and human islet cell preparations. MATERIALS AND METHODS: The effects of Nacystelyn, a salt derivative of N-acetyl-L-cysteine, were first assessed on procoagulant activity induced in human plasma by recombinant tissue factor, human primary duct cells or human islet cell preparations. The influence of Nacystelyn on clot formation, platelet counts and D-dimers were measured in a whole blood tubing loop model. Human beta cell viability and insulin synthesis after Nacystelyn treatment were assessed to exclude cytotoxicity of Nacystelyn. RESULTS: Nacystelyn efficiently inhibited the procoagulant activity of human recombinant tissue factor, primary duct cells and human islet cell preparations at clinically relevant concentrations without cellular toxicity. CONCLUSIONS/INTERPRETATION: Nacystelyn is a pharmaceutical candidate to reduce early beta cell loss related to tissue factor-dependent coagulation after islet transplantation.

Acetylcysteine↗

Is there an optimal time for laparoscopic cholecystectomy in acute cholecystitis?

BACKGROUND: Laparoscopic cholecystectomy (LC) is safe in acute cholecystitis, but the exact timing remains ill-defined. This study evaluated the effect of timing of LC in patients with acute cholecystitis. METHODS: Prospective data from the hospital registry were reviewed. All patients admitted with acute cholecystitis from June 1994 to January 2004 were included in the cohort. RESULTS: Laparoscopic cholecystectomy was attempted in 1,967 patients during the study period; 80% were women, mean patient age was 44 years (range, 20-73 years). Of the 1,967 LC procedures, 1,675 were successful, and 292 were converted to an open procedure (14%). Mean operating time for LC was 1 h 44 min (SD +/- 50 min), versus 3 h 5 min (SD +/- 79 min) when converted to an open procedure. Average postoperative length of stay was 1.89 days (+/- 2.47 days) for the laparoscopic group and 4.3 days (+/- 2.2 days) for the conversion group. No clinically relevant differences regarding conversion rates, operative times, or postoperative length of stay were found between patients who were operated on within 48 h compared to those patients who were operated on post-admission days 3-7. CONCLUSIONS: The timing of laparoscopic cholecystectomy in patients with acute cholecystitis has no clinically relevant effect on conversion rates, operative times, or length of stay.

Adult↗

Nephrotoxicity of uranyl acetate: effect on rat kidney brush border membrane vesicles.

Since the Gulf war exposure to depleted uranium, a known nephrotoxic agent, there is a renewed interest in the toxic effects of uranium in general and its mechanism of nephrotoxicity which is still largely unknown in particular. In order to investigate the mechanism responsible for uranium nephrotoxicity and the therapeutic effect of urine alkalization, we utilized rat renal brush border membrane vesicles (BBMV). Uranyl acetate (UA) caused a decrease in glucose transport in BBMV. The apparent K (i) of uranyl was 139+/-30 microg uranyl/mg protein of BBMV. Uranyl at 140 microg/mg protein of BBMV reduced the maximal capacity of the system to transport glucose [V (max) 2.2+/-0.2 and 0.96+/-0.16 nmol/mg protein for control and uranyl treated BBMV (P<0.001), respectively] with no effect on the apparent K (m) (1.54+/-0.33 and 1.54+/-0.51 mM for control, and uranyl treated BBMV, respectively). This reduction in V(max) is at least partially due to a decrease in the number of sodium-coupled glucose transporters as apparent from the reduction in phlorizin binding to the uranyl treated membranes, V (max) was reduced from 247+/-13 pmol/mg protein in control BBMV to 119+/-3 pmol/mg protein in treated vesicles (P<0.001). The pH of the medium has a profound effect on the toxicity of UA on sodium-coupled glucose transport in BBMV: higher toxicity at neutral pH (around pH 7.0), and practically no toxicity at alkaline pH (7.6). This is the first report showing a direct inhibitory dose and pH dependent effect of uranyl on the glucose transport system in isolated apical membrane from kidney cortex.

Alkaline Phosphatase↗

Plethysmography and impulse oscillometry assessment of tiotropium and ipratropium bromide; a randomized, double-blind, placebo-controlled, cross-over study in healthy subjects.

AIMS: Spirometry, plethysmography and impulse oscillometry (IOS) measure different aspects of lung function. These methods have not been compared for their ability to assess long- and short-acting anticholinergic agents. We therefore performed a double-blind, placebo-controlled, four-way cross-over study in 30 healthy subjects. METHODS: Single doses of tiotropium bromide (Tio) 54 and 18 mcg, ipratropium bromide (IB) 40 mcg and placebo were administered. Specific conductance (sGaw), total lung capacity (TLC), inspiratory capacity (IC) and residual volume (RV) were measured using plethysmography, while IOS measured resistance (R5-25) and reactance (RF and X5). Pulmonary function was measured for 26 h post dose. RESULTS: Tio caused significant improvements in sGaw, forced expiratory voume in 1 s (FEV(1)), maximum mid-expiratory flow (MMEF) and R5-R25 at time points up to 26 h, with no clear differences between doses. IB improved the same parameters, but only up to 8 h. The weighted mean change (0-24 h) caused by Tio 54 mcg compared with placebo for FEV(1) was 240 ml (95% confidence interval 180, 300), while for sGaw the ratio of geometric means (Tio compared with placebo) was 1.35 (1.28, 1.41). Neither drug caused consistent statistically significant changes in RF, forced vital capacity, TLC or IC over 26 h. RV was significantly improved from 8 to 24 h by Tio 54 mcg only. CONCLUSIONS: In addition to spirometry, IOS resistance measurements and sGaw can distinguish between the effects of long- and shortacting anticholinergic effects in healthy subjects.

Adult↗

Severe atherosclerosis of the aorta and development of peripheral T-cell lymphoma in an adolescent with angiolymphoid hyperplasia with eosinophilia.

We report an adolescent girl with a history of angiolymphoid hyperplasia with eosinophilia (ALHE) diagnosed at the age of 10 years. The patient also suffered from chronic persistent multiresistant herpes simplex virus infection. Atherosclerotic occlusive disease of the abdominal aorta and its major branches was observed at the age of 17 years, necessitating vascular surgical intervention 1 year later because of disease progression. Histological examination of the aorta disclosed widespread atherosclerosis and high levels of gene expression of both T-helper cell type (Th) 1- and Th2-derived cytokines. This suggests that a highly stimulated systemic immune response including increased production of both Th1- and Th2-derived cytokines such as interferon-gamma and interleukin-4 may result in severe atherosclerotic lesions at a very young age. In addition, the patient developed a peripheral T-cell lymphoma at the age of 18 years. Neither systemic atherosclerosis nor T-cell lymphoma has been reported in association with ALHE. It is suggested that a highly stimulated dysfunctional immune response may play a key role in persistent inflammatory disease and premature development of atherosclerosis as well as malignant transformation of T cells.

Adolescent↗

Mature dendritic cells differentiated in the presence of interferon-beta and interleukin-3 prime functional antigen-specific CD8 T cells.

Dendritic cell (DC)-based immunization represents a promising approach for the immunotherapy of cancer. The optimal conditions required to prepare DCs remain to be defined. Monocytes incubated in the presence of interferon (IFN)-beta and interleukin (IL)-3 give rise to a distinct type of DCs (IFN-beta/IL-3 DCs) that are particularly efficient at eliciting IFN-gamma and IL-5 production by allogeneic helper T cells. We assessed the capacity of this new type of DCs to prime antigen-specific naive CD8(+) T cells and compared them to the conventional DCs differentiated in the presence of granulocyte-macrophage colony stimulating factor (GM-CSF) and IL-4 (GM-CSF/IL-4 DCs). We demonstrate that IFN-beta/IL-3 DCs matured by TLR3 or CD40 ligation efficiently prime Melan-A(26-35)-specific CD8(+) T cells in vitro, at a similar level as GM-CSF/IL-4 DCs. Activated antigen-specific CD8(+) T cells produced IFN-gamma and displayed potent cytotoxic activity against peptide-pulsed target cells. Expansion of CD8(+) T cell numbers was generally higher following priming with CD40-L than with polyinosinic-polycytidylic acid (poly I:C) matured DCs. Cytolytic activity was induced by both maturing agents. These data indicate that IFN-beta/IL-3 DCs represent a promising cell population for the immunotherapy of cancer.

CD40 Ligand↗

T cell-mediated immune responses in human newborns: ready to learn?

Infections with intracellular pathogens are often more severe or more prolonged in young infants suggesting that T cell-mediated immune responses are different in early life. Whereas neonatal immune responses have been quite extensively studied in murine models, studies of T cell-mediated immunity in human newborns and infants are scarce. Qualitative and quantitative differences when compared with adult immune responses have been observed but on the other hand mature responses to certain vaccines and infectious pathogens were demonstrated during the postnatal period and even during foetal life. Herein, we review the evidence suggesting that under appropriate conditions of stimulation, protective T cell-mediated immune responses could be induced by vaccines in early life.

Dendritic Cells↗

Predominance of type 1 CD4+ T cells in human abdominal aortic aneurysm.

The functional repertoire of T cells in abdominal aortic aneurysm (AAA) and the exact nature of aortic wall adaptive cellular immune responses still remains a matter of debate. In this study, we sought to determine whether type 1 or type 2 responses occur predominantly in human aneurysmal aortic lesions. We first examined the phenotype and cytokine secretion profile of T lymphocytes freshly isolated from aneurysmal aortic wall for comparison with their circulating counterparts using flow cytometry. We found that both populations of infiltrating CD4(+) and CD8(+)T cells displayed a unique activated memory phenotype. In addition, we identified the presence in human aneurysmal aortic lesion of CD4(+)T cells producing high levels of interferon (IFN)-gamma but not interleukin (IL)-4, reflecting their type 1 nature. Quantitative analysis of cytokine gene expression confirmed increased IFN-gamma transcript levels in infiltrating cells compared to controls. We next analysed aortic wall responses using LightCycler-based quantitative real-time reverse transcription-polymerase chain reaction. Compared to control non-diseased aortic samples, we demonstrated that whole AAA tissues exhibited high mRNA levels of IFN-gamma but not IL-4. Overexpression of the transcription factor T-bet in the absence of significant GATA-3 expression further assessed the type 1 polarization of aortic wall immune responses. These findings indicate that type 1 CD4(+)T cells predominate in human AAA lesions. This study has important implications for the pathogenesis of aneurysm disease. Through the production of IFN-gamma, T cells may indeed contribute to orchestrate extracellular matrix remodelling.

Aged↗

CD40 expression on human pancreatic duct cells: role in nuclear factor-kappa B activation and production of pro-inflammatory cytokines.

AIMS/HYPOTHESIS: Human pancreatic duct cells are closely associated with islet beta cells, and contaminate islet suspensions transplanted in Type 1 diabetes mellitus patients. Activated duct cells produce cytotoxic mediators and possibly contribute to the pathogenesis of Type 1 diabetes mellitus or islet graft rejection. As CD40 transduces activation signals involved in inflammatory and immune disorders, we investigated CD40 expression on duct cells and their response to CD40 engagement. METHODS: CD40 expression on human pancreatic duct cells was analysed by flow cytometry and immunohistochemical analyses. To assess the function of CD40 expression on duct cells, activation of the transcription factor nuclear factor-kappa B was determined using electrophoretic mobility shift assay and ELISA. Cytokine mRNA levels were quantified by real-time RT-PCR, and protein levels by Luminex technology. RESULTS: Isolated human pancreatic duct cells and Capan-2 cell lines were found to express constitutively CD40. The expression of CD40 on duct cells was confirmed in vivo on human normal and pathological pancreatic specimens. CD40 ligation on Capan-2 cells induced rapid nuclear factor-kappa B activation, and supershift assays demonstrated that p50/p65 heterodimers and p50/p50 homodimers were present in the activated complexes in the nucleus. This activation was accompanied by tumour necrosis factor-a and interleukin-1beta mRNA accumulation. Tumour necrosis factor-alpha protein secretion was confirmed in CD40-activated Capan-2 cells and in isolated human pancreatic duct cells. CONCLUSIONS/INTERPRETATION: Interaction between activated T lymphocytes expressing CD40 ligand and duct cells expressing CD40 may contribute to the immune responses involved in Type 1 diabetes mellitus and islet graft rejection. Interfering with CD40-mediated duct cell activation could alleviate beta cell damage of immune origin.

CD40 Antigens↗

The fate of dendritic cells in a mouse model of liver ischemia/reperfusion injury.

Ischemia/reperfusion during liver transplantation triggers a complex cascade of inflammatory events that may lead to organ dysfunction. Herein, we investigated the consequences of hepatic ischemia/reperfusion on liver dendritic cells. Liver damage was documented by increased levels of serum alanine aminotransferase and by histopathology showing large areas of hepatocyte cytolysis. MHC class II+ CD45-B220 F4/80 dendritic cells were detected in necrotic areas 20 hours after reperfusion. Dendritic cells freshly isolated from reperfused livers displayed a mature phenotype characterized by upregulated expression of B7 costimulatory molecules; MHC-class II, and CD1d molecules. As shown by real-time PCR, IL-10, and TGF-beta mRNA accumulated in liver dendritic cells isolated after reperfusion, whereas IL-12p40 mRNA levels were decreased and IFN-gamma mRNA levels were unchanged. These results suggest that hepatic ischemia/reperfusion results in maturation of dendritic cells, which preferentially produce inhibitory cytokines.

Alanine Transaminase↗

Unexpected effects of viral interleukin-10-secreting dendritic cells in vivo: preferential inhibition of TH2 responses.

Viral interleukin (IL)-10 (vIL-10) has been widely described as an immunoregulatory cytokine that does not possess the T-cell costimulatory activities of cellular IL-10; it was therefore believed to be a more potent tolerogenic mediator. The immunosuppressive properties of this cytokine are partly attributed to its capacity to render dendritic cells (DCs) unable to undergo full maturation and to activate T cells. We reported here that myeloid DCs retrovirally transduced with vIL-10 had an impaired production of IL-12 and a decreased expression of MHC class II molecules but had minor defects in costimulatory molecule expression and no alteration on CCR5 and CCR7 expression. In mixed leukocyte reaction, vIL-10-transduced C57BL/6 bm12 (MHC class II mismatch) DCs had a reduced capacity to stimulate C57BL/6 wild-type CD4+ T-cell proliferation. We show that bm12 vIL-10-transduced DC administration in CD8-/- C57BL/6 mice promoted IFN-gamma production, down-regulated TH2-type cytokine production, and did not induce skin graft tolerance. These findings suggest that vIL-10-transduced DC may surprisingly facilitate Th1-type inflammatory responses in vivo.

Animals↗

Dendritic cells overexpressing Fas-ligand induce pulmonary vasculitis in mice.

Dendritic cells (DC) genetically engineered to express Fas (CD95) ligand (FasL-DC) have been proposed as immunotherapeutic tools to induce tolerance to allografts. However, we and others recently showed that FasL-DC elicit a vigorous inflammatory response involving granulocytes and can promote Th1-type CD4+ and cytotoxic CD8+ T lymphocytes. This prompted us to evaluate the pathology induced by intravenous injection of FasL-DC in mice. We observed that FasL-DC obtained after retroviral gene transfer of bone marrow precursors derived from Fas-deficient C57Bl/6 mice induce massive pulmonary inflammation and pleuritis one day after a single intravenous injection in C57Bl/6 mice. Two months later, all mice presented granulomatous vasculitis of small to medium sized vessels, alveolar haemorrhage and pleuritis. In these lesions, apoptotic bodies were found in large number. Anti-neutrophilic cytoplasmic and anti-myeloperoxidase autoantibodies were not detected. This study documents that intravenous injection of FasL-DC causes severe lung granulomatous vasculitis. This new animal model for vasculitis is inducible, highly reproducible and shares many features with human Wegener granulomatosis. This model may be an appropriate tool to further investigate the pathogenesis of vasculitis and test new therapeutic strategies. Moreover, our findings highlight the potential severe complications of FasL-DC-based immunotherapy.

Animals↗

Recent advances in pathogenesis and management of hypereosinophilic syndromes.

Idiopathic hypereosinophilic syndrome is a largely heterogeneous disorder defined until now as persistent marked hypereosinophilia of unknown origin generally complicated by end-organ damage. Recent studies clearly indicate that many patients fulfilling the diagnostic criteria of this syndrome can now be classified as presenting one of two major disease variants: the myeloproliferative or the lymphocytic variant. Research in cellular and molecular biology has provided firm evidence for the existence of discrete hematological disorders underlying these variants, questioning the pertinence of continued reference to 'idiopathic' hypereosinophilic syndrome in such patients. Furthermore, identification of these variants has a number of prognostic and therapeutic implications that must be taken into consideration for adequate management of these patients.

Humans↗

[Immunotherapy based on dendritic cells: from experimentation to clinical development].

Although the DC-based immunotherapy of cancer has been promising in animal models, several questions need to be addressed in depth in humans: the generation of various types of dendritic cells, the analysis of their potential and the immunomonitoring of cancer patients. In our laboratory, our efforts have been focused on (i) the study of the cytotoxic activity of dendritic cells; (ii) the generation of a novel population of human dendritic cells from monocytes cultured in IL-3 and IFN-beta; (iii) the optimisation of the immunostimulatory properties of DC using Fas-ligand surexpression or adjuvants promoting DC/gamma-delta T cell interaction.

Adjuvants, Immunologic↗