Harnessing T cell exhaustion and trogocytosis to isolate patient-derived tumor-specific TCR.

To study and then harness the tumor-specific T cell dynamics after allogeneic hematopoietic stem cell transplant, we typed the frequency, phenotype, and function of lymphocytes directed against tumor-associated antigens (TAAs) in 39 consecutive transplanted patients, for 1 year after transplant. We showed that TAA-specific T cells circulated in 90% of patients but display a limited effector function associated to an exhaustion phenotype, particularly in the subgroup of patients deemed to relapse, where exhausted stem cell memory T cells accumulated. Accordingly, cancer-specific cytolytic functions were relevant only when the TAA-specific T cell receptors (TCRs) were transferred into healthy, genome-edited T cells. We then exploited trogocytosis and ligandome-on-chip technology to unveil the specificities of tumor-specific TCRs retrieved from the exhausted T cell pool. Overall, we showed that harnessing circulating TAA-specific and exhausted T cells allow to isolate TCRs against TAAs and previously not described acute myeloid leukemia antigens, potentially relevant for T cell-based cancer immunotherapy.

A "cui prodest" evaluation on the development of a minimally invasive liver surgery program: a differential benefit analysis of open and laparoscopic approach for left and right hemihepatectomies.

BACKGROUND: The correlation between technical feasibility and short-term clinical advantage provided by laparoscopic over open technique for major hepatectomies is unclear. This monocentric retrospective study investigates the possible differences in the benefit provided by minimally invasive approach between left and right hepatectomy, deepening the concept of differential benefit in the setting of anatomical major resections. METHODS: All hemihepatectomies performed from January 2004 to December 2021 were identified in the institutional database. A propensity score method was used to match minimal invasive (MILS) and open pairs in the left hemihepatectomies (LH) and right hemihepatectomies (RH) groups with a 1:1 ratio to adjust any potential selection bias. The differential benefit for left and right hepatectomy provided by laparoscopic over open technique was evaluated in a pure analysis (i.e., including cases converted to open) and a risk-adjusted analysis (i.e., after excluding open conversion from the laparoscopic series). RESULTS: The analysis of the risk-adjusted differential benefit demonstrated better result of the MILS in the RH group than in the LH group, in terms of blood loss (∆ blood loss - 150 and - 350, respectively; differential benefit: 200 mL, p < 0.05), morbidity (∆ rate of morbidity - 11.3% and - 18.1%, respectively; differential benefit: 6.8%, p < 0.05) and length of stay, LOS (∆ LOS - 1 day and - 3 days, respectively; differential benefit: 2 days, p < 0.05). CONCLUSION: While MILS is associated with improved clinical outcomes both in left and right hepatectomy procedures, the greater advantage provided by laparoscopy was documented in patients undergoing right hepatectomy, i.e. for more technically demanding procedures. A MILS program should include the broadest range of liver resections to ensure the full benefits of the laparoscopic technique.

The failure to rescue factor: aftermath analyses on 224 cases of perihilar cholangiocarcinoma.

The term "failure to rescue" (FTR) has been recently introduced in the field of hepato-biliary surgery to label cases in which major postoperative complications lead to postoperative fatality. Perihilar cholangiocarcinoma (PHC) surgery has consistently high postoperative morbidity and mortality rates in which factors associated with FTR are yet to be discovered. The primary endpoint of this study is to compare the Rescue with the FTR cohort referencing patients' characteristics and management protocols applied. A cohort of 224 consecutive patients undergoing surgery for PHC, between 2010 and 2021, was enrolled. Perioperative variables were analyzed according to the severity of major postoperative complications (Clavien ≥ 3a). Kaplan-Meier survival analyses were performed to determine complications' impact on survival. Major complications were reported in 86 cases (38%). Among the major complications' cohort, 72 cases (84%) were graded Clavien 3a-4 (Rescue group), while 14 (16%) cases were graded Clavien 5 (FTR group). Number of lymph-node metastases (OR = 1.33 (1.08-1.63) p = 0.006), poorly differentiated (G3) adenocarcinoma (OR = 7.55 (1.24-45.8) p = 0.028, reintervention (OR = 16.47 (2.76-98.08) p = 0.002), and prognostic nutritional index < 40 (OR = 3.01 (2.265-3.654) p < 0.001) rates were independent predictors of FTR. Right resection side (OR 2.4 (1.33-4.34) p = 0.004) increased the odds of major complications but not of FTR. No difference in overall survival was identified. A distinction of perioperative factors associated with postoperative complications' severity is crucial. Patients developing severe outcomes seem to have different biological and nutritional profiles, showing that efficient preoperative protocols are strategic to identify and avert the risk of FTR.

Flow cytometry data mining by cytoChain identifies determinants of exhaustion and stemness in TCR-engineered T cells.

The phenotype of infused cells is a major determinant of Adoptive T-cell therapy (ACT) efficacy. Yet, the difficulty in deciphering multiparametric cytometry data limited the fine characterization of cellular products. To allow the analysis of dynamic and complex flow cytometry samples, we developed cytoChain, a novel dataset mining tool and a new analytical workflow. CytoChain was challenged to compare state-of-the-art and innovative culture conditions to generate stem-like memory cells (TSCM ) suitable for ACT. Noticeably, the combination of IL-7/15 and superoxides scavenging sustained the emergence of a previously unidentified nonexhausted Fit-TSCM signature, overlooked by manual gating and endowed with superior expansion potential. CytoChain proficiently traced back this population in independent datasets, and in T-cell receptor engineered lymphocytes. CytoChain flexibility and function were then further validated on a published dataset from circulating T cells in COVID-19 patients. Collectively, our results support the use of cytoChain to identify novel, functionally critical immunophenotypes for ACT and patients immunomonitoring.