RESUMEN
BACKGROUND: There is no treatment of choice for the management of acute antibody-mediated rejection (ABMR) in kidney transplant recipients. Plasmapheresis ± intravenous immunoglobulin (IVIg) ± rituximab has been used in different regimens with contradictory results. OBJECTIVE: To compare three regimens of acute ABMR management including plasmapheresis + IVIg ± rituximab in two different rituximab regimens. METHODS: In this prospective, observational study kidney transplant recipients with suspicious ABMR were categorized into three groups. Group 1 patients were treated with plasmapheresis + IVIg. Groups 2 and 3 received weekly rituximab at a dosage of 375 mg/m2 for either 4 doses (group 2 or high dose) or 2 doses (group 3 or low dose) in addition to plasmapheresis + IVIg. RESULTS: 8, 15, and 9 patients were categorized in groups 1, 2, and 3, respectively. There was no difference among the groups in terms of demographic and clinical characteristics of recipients and donors. Although, 1-year graft (37.5%, 60.0%, and 66.7% for groups 1, 2, and 3, respectively; p=0.308) and patients survival (75.0%, 86.7%, and 77.8% for groups 1, 2, and 3, respectively; p=0.730) were not significantly different among studied groups, graft survival was 22%-30% higher in rituximab-treated groups. Estimated glomerular filtration rate at 12th month of follow-up did not differ among groups (56.3±19.6, 57.3±20.6, 48.7±16.1 mL/min/1.73 m2 for groups 1, 2, and 3, respectively; p=0.683). However, kidney function steadily improved over time in rituximab-treated patients. CONCLUSION: Adding high or low doses of rituximab to plasmapheresis + IVIg comparably increased graft survival in suspicious acute ABMR kidney recipients and steadily improved kidney function among survived allografts over time.
RESUMEN
In skin tissue engineering, surface feature of the scaffolds plays an important role in cell adhesion and proliferation. In this study, non-woven fibrous substrate based on poly (lactic-co-glycolic acid) (PLGA) (75/25) were hydrolyzed in various concentrations of NaOH (0.05N, 0.1N, 0.3N) to increase carboxyl and hydroxyl groups on the fiber surfaces. These functional groups were activated by EDC/NHS to create chemical bonding with collagen. To improve bioactivity, the activated substrates were coated with a collagen solution (2mg/ml) and cross-linking was carried out using the EDC/NHS in MES buffer. The effectiveness of the method was evaluated by contact angle measurements, porosimetry, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), tensile and degradation tests as well as in vitro cell attachment and cytotoxicity assays. Cell culture results of human dermal fibroblasts (HDF) and keratinocytes cell line (HaCat) revealed that the cells could attach to the scaffold. Further investigation with MTT assay showed that the cell proliferation of HaCat significantly increases with collagen coating. It seems that sufficient stability of collagen on the surface due to proper chemical bonding and cross-linking has increased the bioactivity of surface remarkably which can be promising for bioengineered skin applications.