Clinical Hemorheology and Microcirculation - Volume 61, issue 2

Authors: Roch, Toralf | Kratz, Karl | Ma, Nan | Lendlein, Andreas

Article Type: Research Article

Abstract: Dendritic cells (DC) contribute to immunity by presenting antigens to T cells and shape the immune response by the secretion of cytokines. Due to their immune stimulatory potential DC-based therapies are promising approaches to overcome tolerance e.g. against tumors. In order to enforce the immunogenicity of DCs, they have to be matured and activated in vitro , which requires an appropriate cell culture substrate, supporting their survival expansion and activation. Since most cell culture devices are not optimized for DC growth, it is hypothesized that polymers with certain physicochemical properties can positively influence the DC cultures. With the aim …to evaluate the effects that polymers with different chemical compositions have on the survival, the activation status, and the cytokine/chemokine secretion profile of DC, their interaction with polystyrene (PS), polycarbonate (PC), poly(ether imide) (PEI), and poly(styrene-co -acrylonitrile) (PSAN)-based cell culture inserts was investigated. By using this insert system, which fits exactly into 24 well cell culture plates, effects induced from the culture dish material can be excluded. The viability of untreated DC after incubation with the different inserts was not influenced by the different inserts, whereas LPS-activated DC showed an increased survival after cultivation on PC, PS, and PSAN compared to tissue culture polystyrene (TCP). The activation status of DC estimated by the expression of CD40, CD80, CD83, CD86 and HLA-DR expression was not altered by the different inserts in untreated DC but slightly reduced when LPS-activated DC were cultivated on PC, PS, PSAN, and PEI compared to TCP. For each polymeric cell culture insert a distinct cytokine profile could be observed. Since inserts with different chemical compositions of the inserts did not substantially alter the behavior of DC all insert systems could be considered as alternative substrate. The observed increased survival on some polymers, which showed in contrast to TCP a hydrophobic surface, could be beneficial for certain applications such as T cell expansion and activation. Show more

Keywords: Biomaterials, dendritic cells, cell culture device, amorphous polymers

DOI: 10.3233/CH-152004

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 2, pp. 347-357, 2015

Authors: Prantl, Lukas | Geis, Sebastian | Lamby, Philipp | Jung, Ernst Michael

Article Type: Research Article

Abstract: Complications rates after free flap transplantation still amount up to 5% . Consequently a reliable monitoring system is of high importance in plastic and reconstructive surgery. The following guidelines provide an overview of the current opportunities for free flap planning and monitoring with ultrasound and in particular with contrast enhanced ultrasound.

Keywords: Flap monitoring, ultrasound, CEUS, contrast enhanced ultrasound, microvascularization, microperfusion

DOI: 10.3233/CH-152005

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 2, pp. 359-365, 2015

Authors: Sievers, Henrieke | Hirschberg, Ruth M. | Hiebl, Bernhard | Hünigen, Hana | Plendl, Johanna

Article Type: Research Article

Abstract: Human microvascular ECs from the neonatal foreskin of two donors purchased from one distributor were used in an angiogenesis assay under the same culture conditions. Different angiogenic potency was apparent in these two batches (ECang and ECnon-ang ). During the cultivation period of three weeks, ECang ran through all stages of angiogenesis starting from proliferation to migration up to the formation of three-dimensional capillary-like structures. Despite of expression of endothelial markers, ECnon-ang showed excessive intracellular storage of lipids in form of multilamellar bodies and decreased angiogenic potency in contrast to its counterpart, ECang . Results indicate that …lipid metabolism differs in ECang versus ECnon-ang . This study points up that these differences are based on the different donors and presents a novel and valuable model for the study of mechanisms of atherosclerosis in endothelial cells in vitro . Show more

Keywords: Foreskin, fetal bovine serum, multilamellar bodies, atherosclerosis

DOI: 10.3233/CH-152002

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 2, pp. 367-383, 2015

Authors: George, S. | Noack, M. | Vanek, M. | Rentzsch, J. | Röber, N. | Conrad, K. | Roggenbuck, D. | Küpper, J.-H.

Article Type: Research Article

Abstract: Myasthenia gravis (MG) is an autoimmune disease characterized by the formation of pathogenic autoantibodies mostly targeting the nicotinic acetylcholine receptor (AChR). The AChR is composed of two alpha subunits and one subunit of each beta, delta and gamma (fetal AChR), or epsilon (adult AChR), respectively. Serological diagnostics is commonly done by radioimmunoassay (RIA). Here we used an indirect immunofluorescence assay with MG patient sera on transiently transfected HEp-2 cells expressing selected components of the AChR. Our data show that already 12 out of 13 MG patient sera showed autoantibody binding to HEp-2 cells transfected to express the alpha subunit solely. …Interestingly, 11 out of 13 patient sera reacted positive with cells transfected to reconstitute the complete fetal AChR, but only 6 out of 13 sera showed positive signals with cells expressing the components of adult AChR. Moreover, there was no strict correlation of the serum concentration required to obtain clear-cut fluorescence signals to the antibody titer as measured by RIA. It will be an interesting topic to further investigate if the optimal serum dilution for indirect immunofluorescence as well as the autoantibody binding preferences to defined AChR subunits and to the adult versus the fetal receptor variant could provide additional predictive value in MG diagnostics. Show more

Keywords: Acetylcholine receptor, autoantibodies, cell-based assay, HEp-2 cells, indirect immunofluorescence, multiplex diagnostics, Myasthenia gravis, radioimmunoassay, serological diagnostics

DOI: 10.3233/CH-151999

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 2, pp. 385-396, 2015

Authors: Kuss, N. | Bauknecht, E. | Felbinger, C. | Gehm, J. | Gehm, L. | Pöschl, J. | Ruef, P.

Article Type: Research Article

Abstract: Determination of shear stresses at given shear rates with the LS 300 allows approximation of flow curves by mathematical models and to calculate viscosities of non-Newtonian fluids across the entire physiological shear range. Particular in preterm neonates, which in comparison to term neonates and adults have a substantially lower mean arterial blood pressure (MAP), rheological blood properties play a decisive role to maintain the perfusion. Whole blood viscosity was measured in umbilical cord blood taken from 34 preterm neonates using the LS 300 viscometer. In addition aggregation index, plasma viscosity, hematocrit and red blood cell (RBC) deformability was determined. The …highest quality of approximation of the flow curve of whole blood was achieved by the method of Ostwald. Shear stresses of whole blood of preterm neonates were significantly lower compared to term neonates at similar shear rates (velocity range 6.16 s–1 –50 s–1 ). With hematocrit calculated to 0.40 the related exponent (n) of the viscosity of preterm neonates (by Ostwald) showed a significant lower exponent (n) (0.71 ± 0.07) than term neonates (0.76 ± 0.06). The highest quality of approximation of the flow curve of plasma was achieved with the model of Ostwald in preterm neonates as well as in term neonates. The viscosity of plasma determined by Newton was lower for preterm neonates (0.89 ± 0.19) than for term neonates (1.04 ± 0.16). Concurrent to term neonates the whole blood of preterm neonates showed a very low aggregation index (term neonates 2.97 ± 2.10; preterm neonates 2.37 ± 1.32) and preterm neonates showed higher RBC deformability than term neonates. Because of the physiologically lower MAP and the particular viscous properties of neonatal blood special attention should be given when treating neonates with conventional blood products derived from adult donors. Show more

Keywords: Ostwald, Casson, preterm, viscosity, flow curve, yield shear stress

DOI: 10.3233/CH-152007

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 2, pp. 397-405, 2015