Characterization of in vivo tumorigenicity tests using severe immunodeficient NOD/Shi-scid IL2Rγnull mice for detection of tumorigenic cellular impurities in human cell-processed therapeutic products

The contamination of human cell-processed therapeutic products (hCTPs) with tumorigenic cells is one of the major concerns in the manufacturing and quality control of hCTPs. However, no quantitative method for detecting the tumorigenic cellular impurities is currently standardized. NOD/Shi-scid IL2Rγnull (NOG) mice have shown high xeno-engraftment potential compared with other well-known immunodeficient strains, e.g. nude mice. Hypothesizing that tumorigenicity test using NOG mice could be a sensitive and quantitative method to detect a small amount of tumorigenic cells in hCTPs, we examined tumor formation after subcutaneous transplantation of HeLa cells, as a model of tumorigenic cells, in NOG mice and nude mice. Sixteen weeks after inoculation, the 50% tumor-producing dose (TPD50) values of HeLa cells were stable at 1.3 × 104 and 4.0 × 105 cells in NOG and nude mice, respectively, indicating a 30-fold higher sensitivity of NOG mice compared to that of nude mice. Transplanting HeLa cells embedded with Matrigel in NOG mice further decreased the TPD50 value to 7.9 × 10 cells, leading to a 5000-fold higher sensitivity, compared with that of nude mice. Additionally, when HeLa cells were mixed with 106 or 107 human mesenchymal stem cells as well as Matrigel, the TPD50 values in NOG mice were comparable to those of HeLa cells alone with Matrigel. These results suggest that the in vivo tumorigenicity test using NOG mice with Matrigel is a highly sensitive and quantitative method to detect a trace amount of tumorigenic cellular impurities in human somatic cells, which can be useful in the quality assessment of hCTPs

Rehabilitation in the long-term care insurance domain: a scoping review

Abstract Purpose Since the enactment of the long-term care insurance (LTCI) act in 2000, the number of LTCI users has increased annually. However, evidence regarding what is being carried out as rehabilitation treatment under LTCI is lacking. In this study, a scoping review was performed to bridge this knowledge gap. Methods Articles related to rehabilitation in connection with LTCI published between April 2000 and November 2020 were searched for in PubMed, CINAHL, CENTRAL (Cochrane Central Register of Controlled Trials), Ichushi Web Ver.5, and CiNii and randomized controlled trials (RCTs) of rehabilitation provided under LTCI were examined. Results Of the 15,572 publications identified, 15 RCTs, including rehabilitation treatment by physiatrists and therapists, met the eligibility criteria of our review and were included. The rehabilitation trials in the 15 RCTs varied and included balance training, exercise therapy, cognitive tasks, and activities such as singing and dancing. The results allowed us to focus on three categories: fall prevention, dementia, and theory and tools interventions related to occupational therapy practice. Conclusion The focal points of attention in the rehabilitation treatment of LTCI were identified. However, the physical function, quality of life, and activities of daily living (ADL) of those who “need support” vary from person to person. Therefore, the consolidation of evidence on rehabilitation treatment of LTCI must be continued