Endothelial progenitor cells in sudden sensorineural hearing loss.

CONCLUSIONS: Endothelial progenitor cells (EPCs) are a unique subtype of circulating cells with properties similar to those of embryonal angioblasts. They have the potential to proliferate and to differentiate into mature endothelial cells. EPCs are reduced in patients with vascular risk factors due to a decreased mobilization, an increased consumption at the site of damage or a reduced half-life. The results of this study confirm the existence of an endothelial dysfunction in patients with sudden sensorineural hearing loss (SSHL) and support the vascular involvement in the pathogenesis of the disease. OBJECTIVE: The aim of this study was to evaluate the concentration of EPCs in patients affected by SSHL. METHODS: Twenty-one patients affected by SSHL were evaluated. The number of EPCs was analyzed by flow cytometry analysis of peripheral blood CD34+KDR+CD133+ cells. RESULTS: Circulating levels of EPCs were significantly lower in SSHL patients compared with controls. In particular, CD34+KDR+ cells and CD34+CD133+KDR+ cells were significantly reduced (p < 0.05).

Effect of low-density lipoprotein apheresis on circulating endothelial progenitor cells in familial hypercholesterolemia.

BACKGROUND: Long-term treatment with low-density lipoprotein (LDL) apheresis (LA) has been shown to reduce the incidence of cardiovascular events in patients affected by familial hypercholesterolemia (FH). Data from experimental studies suggest that circulating endothelial progenitor cells (EPCs) can repair the vascular lesions caused by atherosclerosis. Since a reduction of these cells has been demonstrated to predict atherosclerosis progression, the aim of this study was to verify whether LA can increase the percentage of EPCs. METHODS: In 15 patients affected by FH periodically treated with LA, the percentage of EPCs was determined before and after performing LA, and compared with the values of 15 control subjects and 15 hypercholesterolemic patients treated with statins. RESULTS: Significant differences were found in FH patients between the pre-apheresis percentages of CD34+/KDR+, defined as EPCs by a wide consensus of opinion, and the values found 24 h after the procedures (0.00868 +/- 0.003 vs. 0.01009 +/- 0.002%, p < 0.005). Instead, the percentages of CD34+/KDR+/CD133+, considered as an immature subset of EPCs, remained substantially unchanged. However, a significant reduction in the percentage of EPCs was observed in both patient groups as compared to the controls, at all the assessment times. CONCLUSION: In the short-term LA seems to stimulate mobilization of CD34+/KDR+ cells. Hypercholesterolemic patients show a lower percentage of EPCs than controls. There were no differences in the EPCs percentages between the 2 patients groups, despite the fact that LDL cholesterol levels were higher in the group undergoing LA.

Patients with Hereditary Hemorrhagic Telangectasia (HHT) exhibit a deficit of polymorphonuclear cell and monocyte oxidative burst and phagocytosis: a possible correlation with altered adaptive immune responsiveness in HHT.

Hereditary Hemorrhagic Telangiectasia (HHT) is a rare genetic disease characterized by mutations occurring in the endoglin and ALK-1, two receptors of transforming growth factor-beta1. From a pathogenic point of view, a possible involvement of the immune system in HHT has been suggested since a mononuclear cell infiltrate was found around the area of telangiectases. Up until now, no information has been available about the role played by leukocytes in HHT and the mechanisms elicited by secretion of their mediators. However, the fact that a deficit of adaptive immunity in HHT has been reported in a companion paper in this issue will represent a great contribution to the understanding of HHT pathogenesis. The purpose of this study was to evaluate whether patients with HHT manifest also alterations in the innate immune response. Therefore, the phenotype of T, B and natural killer lymphocytes, serum immunoglobulin levels, phagocytosis and oxidative burst activity exerted by polymorphonuclear cells (PMN) and monocytes (MO) were analyzed in 22 patients. Twenty individuals demonstrated single or multiple deficits of PMN and MO functions, while the immunophenotype of lymphocytes and serum concentrations of immunoglobulins were normal. To the best of our knowledge, this is the first demonstration of a reduction in PMN and MO functions in HHT, thus suggesting a higher susceptibility to infectious complications in these patients. The relationship between innate immune deficits and T helper 1 and monocyte-derived cytokine dysfunction in HHT, as previously reported, is discussed.

Cytokine/Chemokine HLDA8 Workshop panel report: analysis of receptors on lymphocytes from cord blood, normal and asthmatic subjects, and HIV positive patients.

Chemokines and cytokines are involved in many processes, both physiological and pathological, particularly the recruitment, differentiation, activation, and proliferation of immune cells taking part in ontogenesis, inflammation, and cancer. It was assumed that chemokines and cytokines receptors are expressed in a regulated manner by human lymphocytes during ontogeny and later on, under the environmental stimulation of antigens they contribute to organogenesis, angiogenesis, and tissue remodeling, as well as modulating leukocyte effector functions. Using monoclonal antibodies classified by the Cytokine/Chemokine section of the 8th International Workshop on Human Leukocyte Differentiation Antigens, we analyzed human lymphocytes in blood samples drawn from the umbilical cord, normal adults, allergic and non-allergic asthma patients, HIV infected, and AIDS positive subjects. The main differences noted between adult and cord blood lymphocytes were related to CCR7 and CXCR4 receptors, which were more strongly expressed on cord blood lymphocytes, confirming the important role of these chemokines during development of the immune system. As with the HIV, CXCR4, and CCR5 co-receptors, we found no differences in CXCR4 expression between HIV and AIDS patients. However CCR5 was more strongly expressed in AIDS patients, which is likely to be associated with the evolution of disease. Further studies are needed to gain a better understanding of the functions of these molecules in the underlying pathogenesis of many diseases and to probe the use of the chemokine receptors as targets for therapeutic intervention.

Effects of oral bacterial immunotherapy in children with atopic eczema/dermatitis syndrome : a pilot study.

BACKGROUND: Atopic eczema/dermatitis syndrome (AEDS) is a chronic inflammatory skin disease, affecting 10-20% of children and 1-3% of adults. The purpose of this pilot study was to assess the clinical and anti-inflammatory effect of bacterial and ribosomal immunotherapy with Immucytal (Pierre Fabre Médicament, France) in children with AEDS. METHODS: Seventeen children with allergic and non-allergic forms of AEDS (AAEDS and NAAEDS, respectively), graded moderate to severe (Severity Scoring of Atopic Dermatitis [SCORAD] index of >25), received ribosomal immunotherapy (Immucytal) once daily according to the standard treatment regimen (4 consecutive days a week for 3 weeks, and then 4 consecutive days a month for 4 months). We assessed the clinical status of AEDS using the SCORAD index at baseline, and after 8 and 20 weeks of treatment. Furthermore, peripheral blood from patients was examined for the frequencies of CD4+ cells expressing interferon (IFN)-gamma and interleukin (IL)-4 using flow cytometry. RESULTS: There was a progressive and significant clinical improvement of AEDS, confirmed by a reduction of the SCORAD index over time in both AEDS forms (p < 0.01). Pooled data from the two groups showed that the mean baseline index of 43 was reduced to 17 after treatment. Overall, these data indicate a marked improvement in total clinical severity of AEDS (-62%). Flow cytometry analysis showed that frequencies of the two CD4+ T cell subsets did not differ significantly from the beginning to the end of the study in both forms of AEDS. However, the percentage of CD4+ cells expressing IL-4 in children with AAEDS tended to decrease by the end of treatment with ribosomal immunotherapy. Clinical and laboratory data confirmed that immunotherapy was well tolerated. CONCLUSIONS: The results of this pilot investigation suggest that ribosomal immunotherapy may be beneficial in the management of AEDS in children, and that this could be at least partially explained by a role in restoring the type 2 helper-T cell imbalance seen in allergic patients. Placebo-controlled, randomized clinical trials are recommended in order to confirm these findings.

Role of cytokines in gonarthrosis and knee prosthesis aseptic loosening.

Cytokines, which have been demonstrated in synovial fluids during various joint diseases, play an important role in mediating synovial inflammation and in regulating the immune response of many inflammatory processes. We studied synovial fluid, serum, and synovial fragments obtained from 33 patients--10 affected by serious gonarthrosis re-quiring a prosthetic implant, 8 with knee prosthesis aseptic loosening, and (as controls) 15 affected by degenerative meniscopathies--to evaluate the degree of inflammation and level of interleukins (IL-2, IL-4, IL-6, IL-10) and interferon gamma secretion. Histological analysis revealed slightly more infiltration by inflammatory cells in the synovial tissue of patients with gonarthrosis and knee prosthesis aseptic loosening than in that of the control group, with a high prevalence of macrophages. Moreover, we observed enhanced production of the studied cytokines, especially in synovial fluid as compared to serum, indicating that in the pathological conditions examined the inflammatory events are mainly localized. Because the role of these cytokines is to modulate inflammation, better knowledge of the involvement of cells and their soluble mediators in articular damage could guide immunomodulating treatment.