Endothelial Function in Children with Acute Lymphoblastic Leukemia (ALL) May Reflect the Clinical Outcome.

Endothelial dysfunction is a common feature of early complications of hemato-oncologic therapy. The aim of our study was to assess the profile of endothelial function at diagnosis time, then during initial treatment phase of acute lymphoblastic leukemia (ALL), and to verify the presence of its correlation with early clinical outcome (ECO). 28 ALL children and 18 healthy age-matched control ones were recruited. Study group was examined at baseline and at 33rd and 78th day of treatment. At each protocol step the endothelial function was assessed by measurement of sP-selectin (CD62-P), PAI-1(serpinE1), sE-selectin (CD62E), sICAM-1(sCD54), sVCAM-1(sCD106), and VEGF concentrations. Higher baseline sICAM-1 and sVCAM-1 levels and lower sP-selectin and VEGF were observed in children with ALL. sICAM-1, sVCAM-1, and sE-selectin levels were decreasing following the treatment with protocol I. Higher sE-selectin and lower baseline sICAM-1 levels were observed in children treated unsuccessfully. Lower PAI-1 levels were observed in children who survived. Higher baseline sE-selectin levels and lower sICAM-1 and VEGF were observed in children treated unsuccessfully. A decrease in sE-selectin and lower PAI-1 at the 78th day of therapy were associated with better ECO. High baseline VEGF and sE-selectin levels, significant increase in PAI-1, and low initial sICAM-1 levels are prognostics for poorer prognosis in the ALL children.

Characterisation of the R3/1 cell line as an alveolar epithelial cell model for drug disposition studies.

The rat cell line R3/1 displays several phenotypical features of alveolar epithelial type I cells. In order to evaluate this cell line as potential in vitro model for drug disposition studies, R3/1 cells were cultured on Transwell filters and the transepithelial electrical resistance (TEER) was measured to test the integrity of cell layers. The mRNA expression of cell junctional components including E-cadherin, occludin, ZO-1 and ZO-2 was studied using reverse transcriptase-polymerase chain reaction (RT-PCR) and the corresponding proteins by immunofluorescence microscopy (IFM). Moreover, the expression pattern of catabolic peptidases, carboxypeptidase M, aminopeptidases (AP): A, B, N and P, gamma-glutamyltransferase (GGT), dipeptidylpeptidase IV, angiotensin-converting enzyme (ACE), and endopeptidases (EP) 24.11 and 24.15 was analysed in R3/1 cells and compared to rat alveolar epithelial I-like cells in primary culture. TEER peaked at 99+/-17Omegacm(2) after 5 days in culture. Addition of 0.1muM dexamethasone (DEX) with 20% foetal bovine serum further increased TEER by 65%. However, none of the culture conditions used in our study yielded monolayers with TEER values comparable to those of primary cultures of rat pneumocytes. No transcripts encoding for E-cadherin and occludin were detected by RT-PCR. However, ZO-1 and -2 mRNA transcripts were found. IFM using a monoclonal antibody against occludin confirmed the absence of the protein in R3/1 cells. Of the investigated proteolytic enzymes, mRNA transcripts encoding APA and APB as well as EP 24.11 and EP 24.15 were detected; a pattern similar to that of rat alveolar epithelial I-like cells in primary culture. Thus, although R3/1 cells express certain markers typical for type I pneumocytes (e.g., T1alpha, ICAM-1, connexin-43, caveolins-1 and -2) they do not form electrically tight monolayers. This excludes R3/1 cells from being used as an in vitro model for alveolar absorption. However, the cell line may be suitable to study stability of inhaled and endogenous proteins.