Double-negative T cells: a promising avenue of adoptive cell therapy in transplant oncology / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Tumor recurrence is one of the major life-threatening complications after liver transplantation for liver cancer. In addition to the common mechanisms underlying tumor recurrence, another unavoidable problem is that the immunosuppressive therapeutic regimen after transplantation could promote tumor recurrence and metastasis. Transplant oncology is an emerging field that addresses oncological challenges in transplantation. In this context, a comprehensive therapeutic management approach is required to balance the anti-tumor treatment and immunosuppressive status of recipients. Double-negative T cells (DNTs) are a cluster of heterogeneous cells mainly consisting of two subsets stratified by T cell receptor (TCR) type. Among them, TCRαβ+ DNTs are considered to induce immune suppression in immune-mediated diseases, while TCRγδ+ DNTs are widely recognized as tumor killers. As a composite cell therapy, healthy donor-derived DNTs can be propagated to therapeutic numbers in vitro and applied for the treatment of several malignancies without impairing normal tissues or being rejected by the host. In this work, we summarized the biological characteristics and functions of DNTs in oncology, immunology, and transplantation. Based on the multiple roles of DNTs, we propose that a new balance could be achieved in liver transplant oncology using them as an off-the-shelf adoptive cell therapy (ACT).

Simultaneous quantification of ginsenoside Rg1 and its metabolites by HPLC-MS/MS: Rg1 excretion in rat bile, urine and feces

Ginsenoside Rg1 (Rg1), the major effective component of ginseng, has been shown to have multiple bioactivities, but low oral bioavailability. The aim of this study was to develop a simple, sensitive and rapid high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, which could be used to validate and quantify the concentrations of Rg1 and its metabolites in Sprague-Dawley rat bile, urine, and feces after oral administration (25 mg/kg). Calibration curves offered satisfactory linearity (>0.995) within the determined ranges. Both intra-day and inter-day variances were less than 15%, and the accuracy was within 80-120%. The excretion recoveries of Rg1, ginsenoside Rh1 (Rh1), and protopanaxatriol (Ppt) in bile, urine, and feces combined were all greater than 70%. The fecal excretion recoveries of Rg1, Rh1, and Ppt were 40.11%, 22.19%, and 22.88%, respectively, whereas 6.88% of Rg1 and 0.09% of Rh1 were excreted in bile. Urinary excretion accounted for only 0.04% of Rg1. In conclusion, the observed excretion profiles for Rg1 and its metabolites after oral administration are helpful for understanding the poor oral bioavailability of Rg1 and will aid further investigations of Rg1 as a pharmacologically active component.