A. L. Pasqui

Extracorporeal photochemotherapy restores Th1/Th2 imbalance in patients with early stage cutaneous T‐cell lymphoma

Extracorporeal photochemotherapy (ECP) has been shown to be a potent activator of peripheral blood macrophages because it causes a marked release of macrophage‐dependent proinflammatory cytokines, and it is therefore currently considered to be a safe and non‐toxic immunomodulatory treatment. On this basis we studied the function of peripheral blood mononuclear cells (PBMC) in eight patients with early stage (Ib) cutaneous T‐cell lymphoma (CTCL), before and 1 year after ECP, together with their clinical and histological responses. In particular we evaluated in vitro phytohaemagglutinin (PHA)‐stimulated proliferation and production of interleukin‐4 (IL‐4) and interferon‐&ggr; (IFN‐&ggr;) as well as lipopolysaccharide (LPS)‐induced production of IL‐12. Before treatment we observed that PBMC of patients produced significantly higher levels of IL‐4 and lower levels of IFN‐&ggr; and IL‐12 than those of healthy control subjects. After 1 year of ECP, IL‐4, IFN‐&ggr; and IL‐12 production no longer differed from that of control subjects. Moreover, we observed a good clinical result matched by histological response. Our data confirm that early‐ stage CTCL patients show a predominantly type‐2 immune response that might be responsible for several immunological abnormalities found in this disease. We have demonstrated that ECP reverses the T‐helper type 1/T‐helper type 2 (Th1/Th2) imbalance and may therefore be considered an efficient biological response modifier.

Time‐dependent effect of statins on platelet function in hypercholesterolaemia

Background Reduction of platelet activity induced by statins has been described as a positive effect exerted by such molecules on vascular thrombotic events. However, the relations among cholesterol (LDL‐C) reduction, the timing of the antiplatelet effect, the involved mechanisms and the doses of each statin able to reduce platelet function are not actually well known. The aim of our study was to evaluate the impact of simvastatin (20 mg day−1), atorvastatin (10 mg day−1), fluvastatin (40 mg day−1) and pravastatin (40 mg day−1) on platelet function in hypercholesterolaemic subjects with relation to (LDL‐C), oxidized‐LDL (ox‐LDL) and antiport mechanism modifications.

Common variable immunodeficiency: a review.

Abstract.Common variable immunodeficiency (CVID) is the commonestnsymptomatic primary antibody deficiency syndrome. Thenpredominant manifestation is hypogammaglobulinemia. CVID isncharacterized by recurrent bacterial infections, especially ofnthe upper and lower respiratory airways, and is also associatednwith an increased incidence of autoimmune and neoplasticndisorders. Most patients are diagnosed as adults and delay innthe recognition of the disease is common. Several T and B cellndefects have been described, although the underlying cause isnstill unknown.

Atorvastatin reduces platelet-oxidized-LDL receptor expression in hypercholesterolaemic patients

Backgroundu2002 Oxidized‐LDL (ox‐LDL) are proatherogenic and platelet‐activating molecules. Atorvastatin reduces platelet activity before cholesterol‐lowering action. CD36 and lectin‐like oxidized‐LDL receptor‐1 (LOX‐1) are specific ox‐LDL receptors expressed also in platelets. This study was planned to address whether the possible rapid effect of atorvastatin on platelets could be related to modulation of ox‐LDL receptors.

Effects of carvedilol on left ventricular remodeling and systolic function in elderly patients with heart failure

Recent studies have shown that carvedilol therapy in patients with heart failure improves clinical outcome and survival, however, the effects of such treatment on left cardiac morphology and function in elderly patients with severe heart failure has not been widely studied.

Extracorporeal photopheresis affects co‐stimulatory molecule expression and interleukin‐10 production by dendritic cells in graft‐versus‐host disease patients

Graft‐versus‐host disease (GVHD) is a major complication of allogeneic bone marrow transplantation. Extracorporeal photochemotherapy (ECP) has been introduced as an alternative treatment for GVHD refractory to conventional immunosuppressive treatment, although its mechanism of action is not yet clear. We investigated, in seven GVHD patients, the effects of ECP on dendritic cell maturation and cytokine production in an in vitro model that could mimic the potential in vivo effect of reinfusion of ECP‐treated peripheral blood mononuclear cells. The model was based on co‐culture of ECP‐treated lymphocytes with monocyte‐derived dendritic cells (DCs) of the same patient. We found that the co‐culture of ECP‐treated lymphocytes with immature DCs reduced CD54, CD40 and CD86 mean fluorescence intensity (MFI) significantly after lipopolysaccharide (LPS) stimulation, without affecting human leucocyte antigen D‐related and CD80 MFI. In the same co‐culture model, DCs produced increased amounts of interleukin (IL)‐10 when co‐cultured with ECP‐treated lymphocytes and stimulated with LPS, while IL‐12 and tumour necrosis factor‐α production were not affected. These results suggest that reinfusion of large numbers of autologous apoptotic lymphocytes is significant for the therapeutic outcome of ECP through down‐regulation of co‐stimulatory molecules on DCs, inducing non‐fully mature DCs with a low signal 2 and up‐regulation of IL‐10, which is an immunosuppressive cytokine.

Extracorporeal photopheresis affects interleukin (IL)-10 and IL-12 production by monocytes in patients with chronic graft-versus-host disease.

Backgroundu2002 Chronic graft‐versus‐host disease (cGVHD) is a major complication of allogeneic bone marrow transplantation. Extracorporeal photopheresis (ECP) has recently been introduced as an alternative treatment for cases of cGVHD refractory to conventional immunosuppressive treatment, but its mechanism of action is not yet clear.

ECP-treated lymphocytes of chronic graft-versus-host disease patients undergo apoptosis which involves both the Fas/FasL system and the Bcl-2 protein family

Chronic graft-versus-host disease (cGVHD) is a severe and frequent complication of allogenic bone marrow transplantation which is often treated with extracorporeal photochemotherapy (ECP) with a positive clinical outcome in patients resistant to conventional protocols. The mechanism of action of ECP has not been fully elucidated, although several authors have reported that it is able to induce apoptosis. Using samples obtained from ten cGVHD patients, we sought to determine whether lymphocytes treated with ECP underwent apoptosis and, above all, the mechanisms involved. Lymphocytes at four stages were isolated: immediately before ECP, from the last buffy coat collected, after UV irradiation prior to reinfusion, and the day after ECP. When cultured for 48xa0h, lymphocytes treated with ECP underwent accelerated apoptosis (tested as annexin V binding cells and as intracellular histone-associated DNA fragments) in comparison with lymphocytes from the other samples. This enhanced programmed cell death could not be prevented by IL-2. Immediately after isolation, there was no difference in Bcl-2 or bax expression among the four different samples, or in Fas and FasL mRNA. However, when cultured, lymphocytes treated with ECP showed a rapid downregulation of Bcl-2, an upregulation of bax with an increased bax/Bcl-2 ratio, a decrease in bcl-2 mRNA and an increase in Fas. No changes were detectable in lymphocytes from the other samples. IL-2 and TNF-α production was not significantly different among lymphocytes from the four samples. In conclusion, in patients affected by cGVHD, ECP induced apoptosis of lymphocytes with the involvement of both the Fas/FasL system and the Bcl-2 protein family.

Different effect induced by treatment with several statins on monocyte tissue factor expression in hypercholesterolemic subjects

Abstract. Platelets and monocytes are involved in atherothrombosis via tissue factor expression. Moreover, they are activated in hypercholesterolemia, a classic risk factor for atherothrombosis. Cholesterol-lowering drugs (statins) reduce cardiovascular risk either by decreasing cholesterol or non-lipidic actions, such as platelet and monocyte activity. The aim of our study was to evaluate the effect of several statins on platelet and monocyte activity in hypercholesterolemic subjects. Platelet activity (P-selectin, cytofluorimetric detection), tissue factor levels (ELISA) and activity (detected in whole blood and cellular preparations by a specific clotting assay) were measured in hypercholesterolemic subjects (41 males, 23 females, aged 34–65 years, total cholesterol 6.86±0.60 mmol/l) treated with atorvastatin 10 mg, simvastatin 20 mg, fluvastatin 40 mg, or pravastatin 40 mg for 6 weeks. P-selectin and tissue factor expression in whole blood and isolated cells were increased in hypercholesterolemic subjects with respect to controls (all P<0.001). Simvastatin, atorvastatin, and fluvastatin reduced monocyte procoagulant activity in whole blood and P-selectin (P<0.01). Tissue factor antigen and activity in isolated cells were further reduced (all P<0.05) independently of cholesterol lowering. Pravastatin decreased tissue factor expression in whole blood in direct relationship to reduction of P-sel and cholesterol (P<0.05). Our data show a different impact of several statins on monocyte tissue factor expression in whole blood, suggesting a possible role of decreased platelet activity and a direct action on monocytes. In contrast, pravastatin decreased monocyte procoagulant activity with relation to cholesteroldependent modifications of platelet function.

T cell activation and enhanced apoptosis in non-ST elevation myocardial infarction

Abstract. Recent studies have shown that inflammation plays a major role in coronary plaque destabilization and in the induction of thrombosis in acute coronary syndromes. The aim of this study was to evaluate circulating lymphocyte activation and apoptosis in patients with non-ST elevation myocardial infarction (NSTEMI) in comparison with subjects with stable angina and with age-matched healthy controls. We considered T cell subpopulations, T cell surface HLA-DR and CD69 expression (evaluated by flow cytometry), lymphomonocyte spontaneous apoptosis (evaluated by ELISA), and IL2 production (evaluated by ELISA) in peripheral blood within 6 hours of onset of NSTEMI. We also investigated Fas expression on T cells (evaluated by flow cytometry) and FasL mRNA (evaluated by RT-PCR), as well as Fas functionality. In NSTEMI patients we found a significant increase of HLADR+ CD3+ and CD69+CD4+ cells. Spontaneous apoptosis was significantly increased in NSTEMI patients in comparison with the two control groups and was associated with an increased expression of Fas, an increased susceptibility to Fas agonist (CH11), and a normal production of IL2 in cell cultures. These data suggest that the enhanced apoptosis is due to a mechanism of “active” antigen-driven death, induced by the expression of death cytokines and not by the failure of cell growth factors. We conclude that peripheral lymphocytes are activated in NSTEMI and undergo an enhanced programmed cell death due to activation mechanisms. It is likely that lymphocyte activation occurs before the onset of acute ischemia and contributes to the plaque rupture and to the myocardial ischemic insult.