Search

Assuring viral safety of bioreactors in upstream bioprocessing is an important issue in manufacturing biologicals. Nanofiltration of cell culture media components is a robust yet expensive method of assuring biosafety. The present article investigates the performance of mAb-producing Chinese hamster ovary (CHO) cells using 20 nm-filtered chemically defined medium in WAVE Cellbag™ bioreactor in a 10L pilot scale. For 20-nm virus retentive filtration nanocellulose-based non-woven filter paper developed at Uppsala University was used. The cell performance in WAVE Cellbag™ bioreactor was quantified with respect to cell viability, metabolic activity, and protein yield and compared to internal reference data from stirred tank-type bioreactor. The results revealed that 20-nm filtered supplemented chemically-defined media supported the growth of mAb-producing CHO cells, with desirable cell metabolic activity and mAb yield. The observed differences between the reference data from unfiltered media in the stirred tank bioreactor and nanofiltered media in WAVE Cellbag™ bioreactor were mainly due to the configuration of the equipment rather than due to nanofiltraion. The results represent an important step forward for scaling up bioprocesses using cost-efficient nanocellulose-based nanofilters in upstream bioprocessing.

Ο σκληροατροφικός λειχήνας του αιδοίου είναι μία χρόνια φλεγμονώδη δερματοπάθεια, αγνώστου αιτιολογίας. Ένα ποσοστό περίπου 5 % είναι δυνατόν να εξελιχθεί σε ακανθοκυτταρικό καρκίνο.Η συγκεκριμένη μελέτη αποσκοπεί στη αριθμητική αξιολόγηση των κυττάρων Langerhans στο σκληροατροφικό λειχήνα του αιδοίου και στη συσχέτιση των πιθανών μεταβολών με την εμφάνιση ακανθοκυταρικού καρκίνου.Η συσχέτιση μίας αυτοάνοσης και μίας νεοπλασματικής διαταραχής αξιολογώντας τις μεταβολές των κυττάρων Langerhans αποτελεί μία περίπλοκη διαδικασία, λόγω της πολυπλοκότητας των παθογενετικών και παθοφυσιολογικών μηχανισμών που αναπτύσσονται. Εξετάστηκαν 42 ιστολογικά δείγματα βιοψιών γυναικών με σκληροατροφικό λειχήνα αιδοίου, 27 ιστολογικά δείγματα με ακανθοκυτταρικό καρκίνο του αιδοίου και 11 δείγματα από υγιείς γυναίκες. Η συλλογή των δειγμάτων έγινε από το 2009 έως το 2013. Ο μέσος όρος ηλικίας των γυναικών ήταν 60 ± 10 έτη. Επρόκειτο για μια αναδρομική μελέτη ασθενών μαρτύρων (case control study), δεδομένης χρονικής στιγμής (cross sectional). Σε όλες τις ομάδες έγινε κλινική και ιστολογική τεκμηρίωση των νοσημάτων ενώ στη ομάδα ελέγχου διαπιστώθηκε η φυσιολογική αρχιτεκτονική δομής της επιδερμίδας και του χορίου. Στα παραπάνω δείγματα έγινε καταμέτρηση των κυττάρων Langerhans με απλό μικροσκόπιο παρατήρησης και σε μεγέθυνση x400 αφού προηγουμένως έγινε ανοσοϊστοχημική σήμανση των κυττάρων με CD207 (Langerin) και CD1a μονοκλωνικά αντισώματα. Για τη στατιστική ανάλυση των αποτελεσμάτων χρησιμοποιήθηκε η μέθοδος Kruskal-Wallis, Mann-Whitney και ο συντελεστής συσχέτισης Spearman. Παρατηρήθηκε στατιστικά σημαντική (p

Bacterial nanocellulose (BNC) is a 3D network of nanofibrils exhibiting excellent biocompatibility. Here, we present the aqueous counter collision (ACC) method of BNC disassembly to create bioink with suitable properties for cartilage-specific 3D-bioprinting. BNC was disentangled by ACC, and fibril characteristics were analyzed. Bioink printing fidelity and shear-thinning properties were evaluated. Cell-laden bioprinted grid constructs (5 × 5 × 1 mm3) containing human nasal chondrocytes (10 M mL-1) were implanted in nude mice and explanted after 30 and 60 days. Both ACC and hydrolysis resulted in significantly reduced fiber lengths, with ACC resulting in longer fibrils and fewer negative charges relative to hydrolysis. Moreover, ACC-BNC bioink showed outstanding printability, postprinting mechanical stability, and structural integrity. In vivo, cell-laden structures were rapidly integrated, maintained structural integrity, and showed chondrocyte proliferation, with 32.8 ± 13.8 cells per mm2 observed after 30 days and 85.6 ± 30.0 cells per mm2 at day 60 (p = 0.002). Furthermore, a full-thickness skin graft was attached and integrated completely on top of the 3D-bioprinted construct. The novel ACC disentanglement technique makes BNC biomaterial highly suitable for 3D-bioprinting and clinical translation, suggesting cell-laden 3D-bioprinted ACC-BNC as a promising solution for cartilage repair.

The introduction of 3D bioprinting is expected to revolutionize the field of tissue engineering and regenerative medicine. The 3D bioprinter is able to dispense materials while moving in X, Y, and Z directions, which enables the engineering of complex structures from the bottom up. In this study, a bioink that combines the outstanding shear thinning properties of nanofibrillated cellulose (NFC) with the fast cross-linking ability of alginate was formulated for the 3D bioprinting of living soft tissue with cells. Printability was evaluated with concern to printer parameters and shape fidelity. The shear thinning behavior of the tested bioinks enabled printing of both 2D gridlike structures as well as 3D constructs. Furthermore, anatomically shaped cartilage structures, such as a human ear and sheep meniscus, were 3D printed using MRI and CT images as blueprints. Human chondrocytes bioprinted in the noncytotoxic, nanocellulose-based bioink exhibited a cell viability of 73% and 86% after 1 and 7 days of 3D culture, respectively. On the basis of these results, we can conclude that the nanocellulose-based bioink is a suitable hydrogel for 3D bioprinting with living cells. This study demonstrates the potential use of nanocellulose for 3D bioprinting of living tissues and organs.

Bacterial nanocellulose (BNC), synthesized by the bacterium Gluconacetobacter xylinus, is composed of highly hydrated fibrils (99 % water) with high mechanical strength. These exceptional material properties make BNC a novel biomaterial for many potential medical and tissue engineering applications. Recently, BNC with cellulose content of 15 % has been proposed as an implant material for auricular cartilage replacement, since it matches the mechanical requirements of human auricular cartilage. This study investigates the biocompatibility of BNC with increased cellulose content (17 %) to evaluate its response in vitro and in vivo. Cylindrical BNC structures (Ø48 × 20 mm) were produced, purified in a built-in house perfusion system, and compressed to increase the cellulose content in BNC hydrogels. The reduction of endotoxicity of the material was quantified by bacterial endotoxin analysis throughout the purification process. Afterward, the biocompatibility of the purified BNC hydrogels with cellulose content of 17 % was assessed in vitro and in vivo, according to standards set forth in ISO 10993. The endotoxin content in non-purified BNC (2,390 endotoxin units (EU)/ml) was reduced to 0.10 EU/ml after the purification process, level well below the endotoxin threshold set for medical devices. Furthermore, the biocompatibility tests demonstrated that densified BNC hydrogels are non-cytotoxic and cause a minimal foreign body response. In support with our previous findings, this study concludes that BNC with increased cellulose content of 17 % is a promising non-resorbable biomaterial for auricular cartilage tissue engineering, due to its similarity with auricular cartilage in terms of mechanical strength and host tissue response.

To assess the efficacy of methylprednisolone aceponate 0.1% (MPA 0.1%) in female genital lichen sclerosus (GLS) and efficacy of MPA, tacrolimus or emollient for prevention of flares.A single-center, retrospective study was conducted. At baseline, female patients with relapsing GLS (n = 46) were treated with MPA 0.1% applied once daily for 8 weeks. Visual Analog Scale (VAS) score for vulvar pruritus and Investigator's Global Assessment (IGA) score were recorded at baseline, weeks 8 and 20. At week 8, patients responsive to treatment (n = 38) were further treated with MPA 0.1% twice weekly (n = 15), tacrolimus once daily (n = 13) or topical emollient once daily (n = 10), as maintenance therapy until week 20.Both VAS and IGA median score was significantly decreased from baseline to week 8 (p = 0.000). At week 20, both median VAS and IGA scores differed significantly between patients treated with emollient and patients treated with MPA 0.1% (p = 0.000) and patients treated with emollient and patients treated with tacrolimus (p = 0.000); patients treated with MPA 0.1% presented no significant difference in either median VAS score (p = 0.032) or median IGA score (p = 0.636) at week 20 compared to patients treated with tacrolimus.MPA 0.1% is effective in relapsing female GLS. MPA 0.1% and tacrolimus have equal efficacy in preventing relapses.