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At least 811 records · Page 45Linked to original sources
PubMed2006

Inhibitors of kinesin Eg5: antiproliferative activity of monastrol analogues against human glioblastoma cells.

The inhibition of kinesin Eg5 by small molecules such as monastrol is currently evaluated as an approach to develop a novel class of antiproliferative drugs for the treatment of malignant tumours. Therefore, we studied the effects of the new monastrol analogues enastron, dimethylenastron and vasastrol VS-83 on the proliferation of human glioblastoma cells in the kinetic crystal violet assay. Compared to monastrol, the new cell cycle specific compounds showed an at least one order of magnitude higher anti proliferative activity against U-87 MG, U-118 MG, and U-373 MG glioblastoma cells. The compounds were neither inactivated by hydrolysis nor by binding to serum proteins. Moreover, we demonstrated the characteristic monoaster formation after incubation of cells with the new compounds by confocal laser scanning microscopy. We also showed that the arrangement of beta-actin and tubulin, vital components of the cyto-skeleton of mitotic and quiescent cells, were not affected by the new compounds. Due to the necessity of overcoming the blood-brain barrier in the treatment of brain tumours, we investigated if the new monastrol analogues are modulators or substrates of the p-glycoprotein (p-gp) 170 by a flow cytometric calcein-AM efflux assay. The tested compounds showed no modulating effects on the p-gp function. With respect to the treatment of primary and secondary CNS tumours, the results of our experiments suggest that the new monastrol analogues represent an interesting class of potential anticancer drugs, predicted to be less neurotoxic in comparison to classical tubulin inhibitors.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1998

Induction of apoptosis in human dermal microvascular endothelial cells and infantile hemangiomas by interferon-alpha.

BACKGROUND: Hemangioma of infancy is an angiomatous disorder characterized by the proliferation of capillary endothelium. It has been shown that interferon-alpha (IFN-alpha) may induce involution of proliferating, life-threatening hemangiomas in children. This IFN-alpha-induced regression of hemangiomas is not accompanied by any T cell response nor by the occurrence of necrosis. METHODS: To determine whether IFN-alpha may induce apoptosis, we cultured human dermal microvascular endothelial cells (HDMEC) with IFN-alpha at concentrations of 100, 500, 1,000 and 2,000 U/ml for 24-72 h and detected apoptosis by terminal deoxynucleotidyl transferase mediated FITC-dUTP nick end labeling (TUNEL). Quantitative analysis was performed using the FACScan and morphological alterations were studied by confocal laser scanning microscopy. In addition to the in vitro study we also analyzed frozen skin sections from proliferating, spontaneously regressing, and IFN-alpha-treated hemangiomas by simultaneous determination of endothelial cells and apoptotic nuclei using an indirect immunofluorescence test in combination with TUNEL. RESULTS: Apoptosis was detected in up to 20% of the IFN-alpha-treated endothelial cells compared to the untreated controls. A maximum of apoptosis was observed after 48 h of stimulation with IFN-alpha in a dose-dependent manner. The analysis of hemangioma biopsies revealed apoptotic endothelial cells in IFN-alpha-treated as well as in spontaneously regressing hemangiomas, but not in proliferating ones. CONCLUSION: These data indicate that the therapeutic effect of IFN-alpha on hemangiomas is based on apoptosis induction of endothelial cells, which might also explain the clinically and histologically observed involution without any sign of inflammation or necrosis.

Antibodies↗
PubMed2007

EGF receptor clustering is induced by a 0.4 mT power frequency magnetic field and blocked by the EGF receptor tyrosine kinase inhibitor PD153035.

Atomic force microscopy (AFM), transmission electron microscopy (TEM), and confocal laser scanning microscopy were used to investigate the effects of a 50 Hz 0.4 mT magnetic field (MF) on the clustering of purified epidermal growth factor receptors (EGFRs) and EGFRs in Chinese hamster lung (CHL) cell membrane. The results demonstrate that exposing purified EGFRs to the MF for 30 min induces receptor clustering. The peak height of apparent clusters increased from 1.42 +/- 0.18 (sham-exposed) to 3.08 +/- 0.38 nm (exposed) while the mean half-width increased from 21.7 +/- 2.2 to 33.0 +/- 4.0 nm. A similar effect was also observed by TEM. Treatment of purified EGFR with PD153035 (PD), an EGFR-specific tyrosine kinase (TK) inhibitor, inhibited the MF-induced EGFR clustering of the purified proteins, an effect also observed for the receptors in cell membrane in the absence of EGF. These results strongly suggest that the 50 Hz 0.4 mT MF interferes with the EGFR signaling pathway, most likely by interacting with the cytoplasmic TK domain.

Animals↗
PubMed1997

HIV coreceptor downregulation as antiviral principle: SDF-1alpha-dependent internalization of the chemokine receptor CXCR4 contributes to inhibition of HIV replication.

Ligation of CCR5 by the CC chemokines RANTES, MIP-1alpha or MIP-1beta, and of CXCR4 by the CXC chemokine SDF-1alpha, profoundly inhibits the replication of HIV strains that use these coreceptors for entry into CD4(+) T lymphocytes. The mechanism of entry inhibition is not known. We found a rapid and extensive downregulation of CXCR4 by SDF-1alpha and of CCR5 by RANTES or the antagonist RANTES(9-68). Confocal laser scanning microscopy showed that CCR5 and CXCR4, after binding to their ligands, are internalized into vesicles that qualify as early endosomes as indicated by colocalization with transferrin receptors. Internalization was not affected by treatment with Bordetella pertussis toxin, showing that it is independent of signaling via Gi-proteins. Removal of SDF-1alpha led to rapid, but incomplete surface reexpression of CXCR4, a process that was not inhibited by cycloheximide, suggesting that the coreceptor is recycling from the internalization pool. Deletion of the COOH-terminal, cytoplasmic domain of CXCR4 did not affect HIV entry, but prevented SDF-1alpha-induced receptor downregulation and decreased the potency of SDF-1alpha as inhibitor of HIV replication. Our results indicate that the ability of the coreceptor to internalize is not required for HIV entry, but contributes to the HIV suppressive effect of CXC and CC chemokines.

Animals↗
PubMed2005

[A prompt method to quantitative assay of alpha-Gal on pig cell surface without injury].

OBJECTIVE: To develop a method for quantitative assay of alpha-Gal on pig cell surface. METHODS: After centrifugation of the anticoagulated blood samples, the white blood cell layer was collected for addition of FITC-BSIB4 and analysis using FCM as well as Laser Scan Confocal Microscope (Bio-Rad). RESULTS: With human blood group B as negative control, and mouse myeloma SP2/0 cells as positive control. the peripheral blood cells of two Chinese pigs were all positive, there were about 9.16 x 10(5) alpha-Galactosyl epitopes expressed on the cell-membrane of granulocytes 1.37 x 10(5) on the monocytes of Banna Minipig Inbred Line (BMI), and 1.16 x 10(6) on the granulocyte and 2.45 x 10(5) on the monocytes of Sichuan White Pig (SWP). The levels of alpha-Galactosyl expression on the surface of blood cells in BMI and SWP differed in various cells, the sequence from high to lower expression levels being on the platelets, granulocytes, monocytes, erthrocytes in each species of pig. CONCLUSION: The method is useful for quantitative assay of alpha-Gal on pig cell surface, and the assay may be used for alpha-Gal for on-site large-scaled screening of living pigs.

Animals↗
PubMed1995

Structural and ultrastructural aspects of isolated immature cochlear outer hair cells maintained in short-term culture.

Immature outer hair cells (OHCs), isolated from developing rat cochlea without using proteolytic enzymes, were maintained in short-term culture in a clot of coagulated plasma. Cell viability was assessed by a laser scanning image cytometer, using double-fluorescent labeling. Light and transmission electron microscopy was used to study the morphology of isolated cells. Ten to 60 healthy OHCs were obtained from one cochlea, either as single isolated cells or clusters containing 2-10 cells from the same row. Although dead cells were observed only 1 h after dissociation, there were still viable cells after 6 h. Isolated OHCs were not perfectly cylindrical, due to the immaturity of their cortical structures. One hour after dissociation the ultrastructural organization of the isolated cells was generally well preserved, but this was followed by dilatation of the Golgi apparatus and endoplasmic reticulum. Specific changes in isolated OHCs were also observed at the subsurface cisternae and cuticular plate. Although degenerating OHCs generally showed a classic pattern of necrosis, certain morphological features reminiscent of apoptosis were also observed. This study emphasises the difficulty involved in investigating isolated immature OHCs in vitro and provides a basis for future research into the physiological requirements of isolated immature OHCs.

Animals↗
PubMed1994

Slit-scanning technique using standard cell sorter instruments for analyzing and sorting nonacrocentric human chromosomes, including small ones.

We have investigated the performance of two types of standard flow cell sorter instruments, a System 50 Cytofluorograph and a FACSTar PLUS cell sorter, for the on-line centromeric index (CI) analysis of human chromosomes. To optimize the results, we improved the detection efficiency for centromeres in two ways. A higher efficiency was obtained first by elongation of the chromosomes and second by introducing a high resolution lens system for laser beam focusing. In the two-parameter flow karyotype of CI and DNA content of human chromosomes, distinct peaks are produced not only by the larger chromosomes 1-8 and X, but by the smaller nonacrocentric chromosomes 9-12 and 16-20 as well. As the chromosomes 9-12 cannot be distinguished by other flow karyotyping methods, we discriminated and sorted chromosomes 12 and 10 from 9 and 11 to investigate the capacity for the separation of chromosomes in this group. A purity of at least 90% was achieved; in the isolated population the fraction chromosomes 12 was 55%; the remaining 45% were chromosomes 10 (40%) and unidentifiable chromosomes (5%).

Cell Separation↗
PubMed2001

Automated topographical cell proliferation analysis.

BACKGROUND: Cell proliferation is often studied using the incorporation of bromodeoxyuridine (BrdU). Immunohistochemical staining is then used to detect BrdU in the nucleus. To circumvent the observer bias and labor-intensive nature of manually counting BrdU-labeled nuclei, an automated topographical cell proliferation analysis method is developed. METHODS: Sections stained with fluorescein-labeled anti-BrdU and counterstained with To-Pro-3 are scanned using confocal laser scanning microscopy (CLSM). For every point in the image, the nucleus density of BrdU-labeled nuclei and the total nucleus density of the neighborhood of that point are calculated from the BrdU and the To-Pro-3 signal, respectively. The ratio of these densities gives an indication of the amount of cell proliferation at that point. The automated measure is validated by comparing it with the ratio of BrdU-stained nuclei to the total number of nuclei obtained from a manual count. RESULTS: A positive correlation is found between the automated measure and the ratios calculated from the manual counting (r = 0.86, P < 0.001). Calculating the topographical cell proliferation using the automated method is faster and does not suffer from interobserver variability. CONCLUSIONS: Automated topographical cell proliferation analysis is a fast method to objectively find differences in cell proliferation within a tissue. This can be visualized by a topographical map that corresponds to the tissue under study.

Animals↗
PubMed1998

Measurement accuracy in confocal microscopy.

Confocal laser scanning microscopy provides optical serial sections through thick biological samples, making it possible to perform both three-dimensional visualization and three-dimensional quantitative analysis. On human lymphocytes, we measured geometrical features, cell contents in DNA and in cyclin A and CDK1 proteins, localization and colocalization of these two proteins. Cells were acquired at a vertical sampling step of 0.5 micron, which gives sufficient information about cell labelling. For the purpose of obtaining fast and reliable data at a reduced time cost, we examined various possibilities to simplify acquisition. For example, it might be possible to increase the vertical sampling step to 2.0 microns while preserving an acceptable accuracy of measurements. Further limiting the acquisition to the central sections appeared to give only rough estimations about the whole cells. Finally, we compared confocal microscopy to conventional two-dimensional epifluorescence microscopy. Confocal microscopy appeared slightly less accurate as regards content estimation, but was an invaluable tool when investigating three-dimensional structures and, more especially, localization of proteins.

Cells, Cultured↗
PubMed1996

DNA quantification in cervical intraepithelial neoplasia thick tissue sections by confocal laser scanning microscopy.

Image analysis of tissue biopsies for determination of DNA content as an early marker of neoplasia is hampered by the complexity of corrections necessary to dea with nuclear truncation and overlap in thin sections. The use of confocal laser scanning microscopy (CLSM) for measurement of cellular DNA content on whole cells within thick tissue sections offers the advantage of preservation of cellular architecture, capacity for 3-dimensional analysis, and absence of sectioning artifacts. We have applied this technique to pararosaniline-Feulgen stained human cervical tissues graded from normal to cervical intraepithelial neoplasia (CIN) III. For the purpose of comparison, 15 microns sections were stained and mapped so that the same cell population could be analyzed by both integrated optical density and fluorescence intensity. Distribution of DNA content from normal cervical epithelial cells 2-3 layers out from the basal cell layer measured by both methodologies showed a stable G0/G1 population with no observable S-phase or G2 cells. Cells measured from areas of increasing CIN grade showed progressively higher DNA content values that were not observable in normal tissue. Although these data are preliminary they suggest that CLSM can be used to identify aneuploid states within defined structural areas of pre-invasive neoplasia.

Coloring Agents↗
PubMed1993

Distribution of cAMP in secondary follicles and its expression in B cell apoptosis and CD40-mediated survival.

Apoptosis occurs at a high rate among B cells in germinal centres (GCs). Isolated GC B cells undergo apoptosis spontaneously when cultured in vitro: such self-destruction can be arrested by protein kinase C-activating phorbol esters and by ligating surface CD40. This study sought to explore whether the cAMP-dependent second messenger system played a role in the regulation of GC cell apoptosis and in ligand-promoted survival. First, the distribution of cAMP in GCs was analysed by immunofluorescence staining and confocal laser scanning microscopy in situ: cytoplasmic cAMP was expressed by all cells but was most abundant in the constitutive cells of the light zones, where GC B cell apoptosis and rescue occur. Isolated GC B cells were found to express higher levels of cAMP than quiescent B lymphocytes as assessed both by a competitive binding assay and a newly developed flow cytometric method. Culturing GC B cells alone increased cAMP level, while those cells rescued with the phorbol ester phorbol myristate acetate (PMA) and anti-CD40 exhibited decreased cAMP levels. Resting B lymphocytes showed no change in cAMP level following culture alone, but a significant increase in cAMP levels when co-cultured with PMA and anti-CD40. These data suggest that given identical signals, resting B cells and GC B cells exhibit differential regulation of the cAMP-dependent second messenger system; moreover, this second messenger system appears to be involved in the regulation of apoptosis in GC B cells.

Antigens, CD↗
PubMed2005

Use of confocal microscopy to analyze the rate of vancomycin penetration through Staphylococcus aureus biofilms.

When bacteria assume the biofilm mode of growth, they can tolerate levels of antimicrobial agents 10 to 1,000 times higher than the MICs of genetically equivalent planktonic bacteria. The properties of biofilms that give rise to antibiotic resistance are only partially understood. Inhibition of antibiotic penetration into the biofilm may play a role, but this has not been proven directly. In this report, penetration of the glycopeptide antibiotic vancomycin into viable Staphylococcus aureus biofilms was analyzed by confocal scanning laser microscopy using a fluorescently labeled derivative of the drug. We found that while vancomycin bound to free-floating bacteria in water within 5 min, it took more than 1 h to bind to cells within the deepest layers of a biofilm. These results indicate that the antibiotic is transported through the depth of the biofilm but that the rate is significantly reduced with respect to its transport through flowing water. This suggests that, whereas planktonic bacteria were rapidly exposed to a full bolus of vancomycin, the bacteria in the deeper layers of the biofilm were exposed to a gradually increasing dose of the drug due to its reduced rate of penetration. This gradual exposure may allow the biofilm bacteria to undergo stress-induced metabolic or transcriptional changes that increase resistance to the antibiotic. We also investigated the role of poly-N-acetylglucosamine, an important component of the S. aureus biofilm matrix, and found that its production was not involved in the observed decrease in the rate of vancomycin penetration.

Anti-Bacterial Agents↗
PubMed1991

High-resolution three-dimensional images from confocal scanning laser microscopy. Quantitative study and mathematical correction of the effects from bleaching and fluorescence attenuation in depth.

Three-dimensional images can be assembled by piling up consecutive confocal fluorescent images obtained by confocal scanning laser microscopy. The present work was based on three-dimensional (50-microns-deep) images at high (x, y) resolution obtained with an MRC-500 after en bloc staining of thick slices of rat liver by chromomycin A3 for nuclear DNA. The results of studies on bleaching, fluorescence excitation and emission intensities at various depths of histologic preparations are described. These effects could be evaluated separately by acquiring piled-up ("brick-stepping") and non-piled-up ("side-stepping") (x, y) images at consecutive depths and also (x, z) images. Empirical equations allowed the fitting of experimental plots of bleaching versus time, at different laser intensities and at different depths, and of fluorescence emission intensity versus depth. The main conclusions were that under our experimental conditions: (1) there was no attenuation by depth of the fluorochrome penetration, (2) there was no attenuation of the exciting beam intensity up to at least 50 microns deep, (3) there was an attenuation of the fluorescence emission intensity by depth, (4) bleaching happened equally on all planes above and below any confocal plane being studied, and (5) the fluorescence bleaching half-life was independent of depth. A mathematical correction scheme designed to compensate for bleaching and for attenuation of fluorescence emission in depth is presented. This correction is required for obtaining three-dimensional images of better quality, for optimal three-dimensional image segmentation and for any quantitative analysis based upon voxel-discretized emission intensities (gray levels)--e.g., estimating, by confocal image cytometry, textural chromatin parameters and nuclear DNA amounts.

Animals↗
PubMed2001

Regulatory volume decrease (RVD) by isolated and in situ bovine articular chondrocytes.

Articular chondrocytes in vivo are exposed to a changing osmotic environment under both physiological (static load) and pathological (osteoarthritis) conditions. Such changes to matrix hydration could alter cell volume in situ and influence matrix metabolism. However the ability of chondrocytes to regulate their volume in the face of osmotic perturbations have not been studied in detail. We have investigated the regulatory volume decrease (RVD) capacity of bovine articular chondrocytes within, and isolated from the matrix, before and following acute hypotonic challenge. Cell volumes were determined by visualising fluorescently-labelled chondrocytes using confocal laser scanning microscopy (CLSM) at 21 degrees C. Chondrocytes in situ were grouped into superficial (SZ), mid (MZ), and deep zones (DZ). When exposed to 180mOsm or 250mOsm hypotonic challenge, cells in situ swelled rapidly (within approximately 90 sec). Chondrocytes then exhibited rapid RVD (t(1/2) approximately 8 min), with cells from all zones returning to approximately 3% of their initial volume after 20 min. There was no significant difference in the rates of RVD between chondrocytes in the three zones. Similarly, no difference in the rate of RVD was observed for an osmotic shock from 280 to 250 or 180mOsm. Chondrocytes isolated from the matrix into medium of 380mOsm and then exposed to 280mOsm showed an identical RVD response to that of in situ cells. The RVD response of in situ cells was inhibited by REV 5901. The results suggested that the signalling pathways involved in RVD remained intact after chondrocyte isolation from cartilage and thus it was likely that there was no role for cell-matrix interactions in mediating RVD.

Animals↗
PubMed2004

MARCO expression on pediatric alveolar macrophages.

BACKGROUND: Phagocytosis of unopsonized pollutant particles by alveolar macrophages (AM) occurs via the macrophage receptor with collagenous structure (MARCO). In a previous study, we demonstrated that the laser scanning cytometer (LSC) can be used to characterize receptor expression in pediatric AM. Since we have demonstrated the presence of ultrafine carbon particles within AM obtained from young infants, we sought to determine MARCO expression by pediatric AM using the LSC, hypothesizing that MARCO expression, and hence the ability to phagocytize pollutant particles, is mature in early infancy. METHODS: AM from 17 healthy children undergoing elective surgery, between 0.1 and 14.1 years of age, were obtained by bronchoalveolar lavage. Cytocentrifuged AM were dual immunostained with monoclonal antibodies to the panmacrophage marker CD68, and either MARCO or an appropriate isotypic control. Expression of MARCO was quantified using LSC and adjusted for cell area. Intensity of immunostaining was compared to each child's own isotypic control. RESULTS: MARCO was present on 98% of pediatric AM. There was no association between age and either intensity of MARCO expression or the proportion of cells expressing MARCO. CONCLUSIONS: We conclude that there is no developmental immaturity in the major receptor responsible for unopsonized particle uptake in healthy young children.

Adolescent↗
PubMed2005

The use of absorption enhancers to enhance the dispersibility of spray-dried powders for pulmonary gene therapy.

BACKGROUND: Pulmonary gene therapy requires aerosolisation of the gene vectors to the target region of the lower respiratory tract. Pulmonary absorption enhancers have been shown to improve the penetration of pharmaceutically active ingredients in the airway. In this study, we investigate whether certain absorption enhancers may also enhance the aerosolisation properties of spray-dried powders containing non-viral gene vectors. METHODS: Spray-drying was used to prepare potentially respirable trehalose-based dry powders containing lipid-polycation-pDNA (LPD) vectors and absorption enhancers. Powder morphology and particle size were characterised using scanning electron microscopy and laser diffraction, respectively, with gel electrophoresis used to assess the structural integrity of the pDNA. The biological functionality of the powders was quantified using in vitro cell (A549) transfection. Aerosolisation from a Spinhaler dry powder inhaler into a multistage liquid impinger (MSLI) was used to assess the in vitro dispersibility and deposition of the powders. RESULTS: Spray-dried powder containing dimethyl-beta-cyclodextrin (DMC) demonstrated substantially altered particle morphology and an optimal particle size distribution for pulmonary delivery. The inclusion of DMC did not adversely affect the structural integrity of the LPD complex and the powder displayed significantly greater transfection efficiency as compared to unmodified powder. All absorption enhancers proffered enhanced powder deposition characteristics, with the DMC-modified powder facilitating high deposition in the lower stages of the MSLI. CONCLUSIONS: Incorporation of absorption enhancers into non-viral gene therapy formulations prior to spray-drying can significantly enhance the aerosolisation properties of the resultant powder and increase biological functionality at the site of deposition in an in vitro model.

Absorption↗
PubMed1997

Intracellular localization of the human receptor for the globular domains of C1q.

This study was performed to determine the localization of the recently described receptor for the globular domain of C1q, gC1qR. In contrast to previous reports, we were not able to detect significant surface expression of gC1qR on Raji cells, monocytes, neutrophils, human or rat mesangial cells, the endothelial cell line EA.hy 926, or HUVEC using FACS analysis. Only by using digoxigenin-conjugated Abs could some surface staining of gC1qR be observed on rat mesangial cells and neutrophils. However, after permeabilizing these cells with saponin, a strong positive intracellular staining for gC1qR was observed by FACS, fluorescence microscopy on coverslips, and confocal laser scanning microscopic analysis. By reflection contrast microscopy and electron microscopy on ultrathin sections of permeabilized Raji cells, it was shown that gC1qR is present in double membranous cytoplasmic vesicles located in the proximity of the plasma membrane. To determine whether certain conditions could induce surface expression of gC1qR, Raji cells were either stimulated with T cell growth factor, LPS, or driven to apoptosis by incubation with fenretinide or by serum depletion. None of the conditions resulted in significant surface expression of gC1qR. Our hypothesis that gC1qR is not a surface molecule but a soluble molecule that is secreted by cells is supported by the observation that gC1qR is found in significant concentrations in supernatants of several cultured cells and in normal human and rat sera. Our results suggest that the recently described gC1qR is not a cell surface receptor, but a soluble binding protein with affinity for the globular heads of C1q. Excreted gC1qR might act as a potential fluid phase regulator of complement activation.

Animals↗
PubMed2001

Polyamide 6 composite membranes: properties and in vitro biocompatibility evaluation.

The aim of the present study was to develop polyamide 6 membrane blended with gelatin and chondroitin sulfate using the phase precipitation method and evaluate its in vitro biocompatibility. Morphology of membranes was studied by laser scanning confocal microscopy which allowed the nondestructive visualization of internal bulk morphology of membranes. Membranes exhibited porous morphology with pores spanning across the membrane width with interconnections at various depths. Membranes showed adequate mechanical properties with tensile strengths of 20.10 +/- 0.64 MPa, % strain of 3.01+/-0.07, and modulus of 1082.50+/-23.50 MPa. In vitro biocompatibility of membranes by direct contact test did not show degenerative effects on NIH3T3 cells and also its leach-out products (LOP), as determined by tetrazolium (MTT) and neutral red uptake (NRU) assay. Mouse peritoneal macrophage cultured in contact with membranes and PTFE control showed comparable expression of activation markers such as CD11b/CD18, CD45, CD14, and CD86 suggesting the membranes' non-activating nature. Membrane LOP did not induce excessive proliferation of mouse splenocytes suggesting its non-antigenic nature. Preliminary blood compatibility of membranes was observed with no detectable hemolysis in static incubation assay. Taken collectively, the present data demonstrate that polyamide 6 composite membranes are biocompatible and prospective candidates for tissue engineering applications.

3T3 Cells↗