The development of hematopoietic stem cell (HSCs) gene therapy for DNA repair disorders, such as Fanconi anemia and Bloom syndrome, is challenging because of the induction of HSCs apoptosis by cytokine stimulation. Although the Baboon envelope pseudotyped lentiviral vector (BaEV-Rless-LV) has been reported as a non -stimulatory gene transfer tool, the virus titer of BaEV-Rless-LV is too low for use in clinical applications. Transfected 293 T cells with helper plasmids, including the BaEV-Rless plasmid, showed morphological changes, such as syncytium formation and detachment. To establish a novel protocol for producing a high titer of BaEV-Rless-LV, we optimized three aspects of a basic virus production protocol by focusing on modifying culture conditions and the use of reagents: the virus titer increased 3-fold when the amount of BaEV-Rless plasmid was increased 1.2-fold; the highest titer was obtained when the viral supernatant was harvested at 48-h post-transfection, despite complete syncytium formation and detachment of the 293 T cells; and the use of poly-L -lysine-coated culture plates to enhance the adhesion and proliferation of 293 T cells and prevent detachment doubled the titer. Collectively, our novel protocol resulted in a 10-fold titer increase compared to the basic protocol and may be useful in clinical applications for treating DNA repair disorders.

Background: Corticosteroid-induced psychiatric disorders (CIPDs) represent an adverse effect that can cause severe emotional and behavioral problems. The aim of the present study was to assess the incidence and risk factors of CIPDs. Methods: A retrospective analysis of 92 pediatric and young adult patients with hematologic malignancies was conducted. Results: The incidence of CIPDs in patients receiving a treatment regimen with prednisolone or dexamethasone was 64.9% and 77.5%, respectively, both of which were significantly higher than that in patients not receiving corticosteroids. Independent risk factors and adjusted odds ratios (95% confidence intervals) related to severe CIPD were 2.15 (1.11–4.18) for dexamethasone (using prednisolone as the reference) and 0.81 (0.75–0.87) for age, suggesting that the odds increase with decreasing age. Frequently observed symptoms, respectively in terms of behavioral and emotional problems were defiance, crying, psychomotor excitement, dysphoria, irritability, and depression. To our knowledge, this is the first report to mention the risk factors and characteristics for clinical symptoms of CIPDs during the developmental process. Conclusions: Healthcare professionals should predict and prepare for psychiatric adverse events prior to chemotherapy in the clinical settings, especially in patients in younger age and receiving a treatment regimen with dexamethasone.