[Effects of dose of erythropoiesis stimulating agents on cardiovascular outcomes, quality of life and costs of haemodialysis. the clinical evaluation of the DOSe of erythropoietins (C.E. DOSE) Trial]. / Effetti della dose degli agenti stimolanti l'eritropoiesi su esiti cardio-cerebrovascolari, qualità di vita e costi in emodialisi.

BACKGROUND: Anaemia is a risk factor for death, adverse cardiovascular outcomes and poor quality of life in patients with chronic kidney disease (CKD). Erythropoietin Stimulating Agents (ESA) are the most used treatment option. In observational studies, higher haemoglobin (Hb) levels (around 11-13 g/dL) are associated with improved survival and quality of life compared to Hb levels around 9-10 g/dL. Randomized studies found that targeting higher Hb levels with ESA causes an increased risk of death, mainly due to adverse cardiovascular outcomes. It is possible that this is mediated by ESA dose rather than haemoglobin concentration, although this hypothesis has never been formally tested. METHODS: We present the protocol of the Clinical Evaluation of the Dose of Erythropoietins (C.E. DOSE) trial, which will assess the benefits and harms of a high versus a low ESA dose therapeutic strategy for the management of anaemia of end stage kidney disease (ESKD). This is a randomized, prospective open label blinded end-point (PROBE) design trial due to enroll 900 haemodialysis patients. Patients will be randomized 1:1 to 4000 UI/week i. v. versus 18000 UI/week i. v. of epoetin alfa, beta or any other epoetin in equivalent doses. The primary outcome of the trial is a composite of cardiovascular events. In addition, quality of life and costs of these two strategies will be assessed. The study has been approved and funded by the Italian Agency of Drugs (Agenzia Italiana del Farmaco (AIFA)) within the 2006 funding plan for independent research on drugs (registered at www.clinicaltrials.gov (NCT00827021)).

[Long-term clinical experience in post-dilution HFR]. / Diciotto mesi di esperienza clinica su HFR on-line in post-diluizione.

PURPOSE: Hemodiafiltration reinfusion (HFR) is characterized by the use of regenerated ultrafiltrate as replacement fluid. We devised a new technique, post-dilution HFR, aimed at increasing the purification efficiency, treatment tolerability and at reducing inflammatory state. METHODS: We performed post-dilution HFR in six uremic patients during 18 months. Dialytic efficacy, filter blood rest and cytokine behavior were evaluated. RESULTS: Neither pyrogenic reactions nor other adverse phenomena were recorded. The tolerance to the treatment was excellent. We observed a high rate of urea extraction and optimal Kt/V values, a high extraction of beta2 microglobulin (beta2-m) and a reduction in blood rest; in addition, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) significantly decreased. CONCLUSIONS. The inversion of the standard HFR configuration allowed us to improve the removal of both urea and beta2-m, and the blood rest, with an optimal tolerability. Moreover, the reduction in cytokine levels could attenuate the uremic microinflammatory state.

Co-stimulatory signal delivered by CD73 molecule to human CD45RAhiCD45ROlo (naive) CD8+ T lymphocytes.

CD73 is a molecule expressed by a subset of CD8+ human T lymphocytes and is involved in T cell activation. CD73 expression and function were analyzed in peripheral blood CD45RAhiCD45ROlo (naive) and CD45RAloCD45ROhi (memory) CD8+ cells. We found that CD73 was expressed by a majority of naive cells (74 +/- 12%), whereas fewer memory cells were CD73+ (29 +/- 10%). Moreover, CD73 was selectively expressed by the CD11b- subset of naive CD8+ cells, which were almost all CD73+. The same result was found on CD8+ cord blood lymphocytes, which prevalently display the naive phenotype. Naive CD8+ CD11b- cells were almost unresponsive to CD3 engagement, but this apparent anergy was completely overcome when CD3 and CD73 were simultaneously cross-linked by plastic-immobilized CD73 and CD3 mAb, showing that CD73 delivers an accessory signal that allows their activation via the CD3/TCR. This costimulatory signal was tenfold more potent than that induced by CD28 ligation. A phosphotyrosine analysis by Western blotting showed that cross-linking of CD73 induced the phosphorylation of two proteins with a molecular mass of approximately 28 and 100 kDa respectively, whereas ligation of CD3 induced phosphorylation of many substrates. When CD3 and CD73 were simultaneously triggered these substrates were hypophosphorylated. Because CD73 is linked to the cell surface by a GPI anchor, the transduction of this signal is probably mediated by a lateral interaction with transmembrane molecules. This hypothesis was assessed by cocapping, which showed that CD73 associates strongly with CD45RC, moderately with CD8, and weakly with CD3. These data suggest that CD73 signaling is coupled to both tyrosine kinase and phosphatase activities.