A single center comparison between three different apheresis systems for autologous and allogeneic stem cell collections.

Three different apheresis systems were used in our center for the collection of peripheral blood progenitor cells (PBPCs): COM.TEC (Fresenius Healthcare), COBE Spectra, and Spectra Optia (both from Caridian BCT). We compared 131 autologous and 56 allogeneic apheresis procedures to elucidate feasibility and effectiveness of the different systems. Collection efficiacy varied significantly with lowest results obtained with COBE Spectra. COM.TEC and Spectra Optia produced lower WBC contamination than COBE Spectra, but at the expense of higher product volume and longer apheresis time. High collection efficacy and a low product volume may be favorable characteristics of the Spectra Optia.

NOS inhibition synchronizes calcium oscillations in human adipose tissue-derived mesenchymal stem cells by increasing gap-junctional coupling.

Adipose tissue-derived mesenchymal stem cells (ASCs) are a promising stem cell source for cell transplantation. We demonstrate that undifferentiated ASCs display robust oscillations of intracellular calcium [Ca(2+) ](i) which may be associated with stem cell maintenance since oscillations were absent in endothelial cell differentiation medium supplemented with FGF-2. [Ca(2+) ](i) oscillations were dependent on extracellular Ca(2+) and Ca(2+) release from intracellular stores since they were abolished in Ca(2+) -free medium and in the presence of the store-depleting agent thapsigargin. They were inhibited by the phospholipase C antagonist U73,122, the inositol 1,4,5-trisphosphate (InsP(3) ) receptor antagonist 2-aminoethoxydiphenyl borate (2-APB) as well as by the gap-junction uncouplers 1-heptanol and carbenoxolone, indicating regulation by the InsP(3) pathway and dependence on gap-junctional coupling. Cells endogenously generated nitric oxide (NO), expressed NO synthase 1 (NOS 1) and connexin 43 (Cx 43). The nitric oxide NOS inhibitors NG-monomethyl-L-arginine (L-NMMA), N(G)-nitro-L-arginine methyl ester (L-NAME), 2-ethyl-2-thiopseudourea, and diphenylene iodonium as well as si-RNA-mediated down-regulation of NOS 1 synchronized [Ca(2+) ](i) oscillations between individual cells, whereas the NO-donors S-nitroso-N-acetylpenicillamine (SNAP) and sodium nitroprusside (SNP) as well as the soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ) were without effects. The synchronization of [Ca(2+) ](i) oscillations was due to an improvement of intracellular coupling since fluorescence recovery after photobleaching (FRAP) revealed increased reflow of fluorescent calcein into the bleached area in the presence of the NOS inhibitors DPI and L-NAME. In summary our data demonstrate that intracellular NO levels regulate synchronization of [Ca(2+) ](i) oscillations in undifferentiated ASCs by controlling gap-junctional coupling.

Association of polymorphisms in the human surfactant protein-D (SFTPD) gene and postnatal pulmonary adaptation in the preterm infant.

BACKGROUND: Surfactant protein-D (SP-D) is a member of the collagenous subfamily of calcium-dependent lectins (collectins). Associations between single nucleotide polymorphisms (SNPs) of the human gene coding surfactant protein-D (SFTPD) and infectious pulmonary diseases have been established by several groups. As the outcome of very preterm infants is mainly determined by pulmonary morbidity, the aim of the present study was to investigate the potential association between sequence variations within the SFTPD gene and pulmonary morbidity in preterm infants below 32 weeks of gestational age (GA). MATERIALS AND RESULTS: Four validated SNPs were genotyped with sequence-specific probes (TaqMan 7000) in 284 newborn infants below 32 weeks of GA. An association between the SNP rs1923537 and the development of respiratory distress syndrome (RDS) in the study population was found with a lower prevalence of RDS in infants having homozygous a minor allele genotype (odds ratio = 1.733, 95% confidence interval 1.139-2.636, adjusted p = 0.0408). Consecutively, the indicated polymorphism was found to be associated with a lower number of repetitive surfactant doses, and with a lower prevalence for the requirement of oxygen supplementation on day 28, as well as the use of diuretics. CONCLUSION: The finding of an association of a variant of the SFTPD gene, that has previously been shown to be associated with increased SP-D serum levels in adult patients with acute respiratory failure, i.e. RDS in preterm infants, may provide a basis for the initial risk assessment of RDS and modification of surfactant treatment strategies. A role for SP-D in neonatal pulmonary adaptation has to be postulated.