Human iPSC-derived CD4+ Treg-like cells engineered with chimeric antigen receptors control GvHD in a xenograft model.

CD4+ T cells induced from human iPSCs (iCD4+ T cells) offer a therapeutic opportunity for overcoming immune pathologies arising from hematopoietic stem cell transplantation. However, most iCD4+ T cells are conventional helper T cells, which secrete inflammatory cytokines. We induced high-level expression of FOXP3, a master transcription factor of regulatory T cells, in iCD4+ T cells. Human iPSC-derived, FOXP3-induced CD4+ T (iCD4+ Treg-like) cells did not secrete inflammatory cytokines upon activation. Moreover, they showed demethylation of the Treg-specific demethylation region, suggesting successful conversion to immunosuppressive iCD4+ Treg-like cells. We further assessed these iCD4+ Treg-like cells for CAR-mediated immunosuppressive ability. HLA-A2 CAR-transduced iCD4+ Treg-like cells inhibited CD8+ cytotoxic T cell (CTL) division in a mixed lymphocyte reaction assay with A2+ allogeneic CTLs and suppressed xenogeneic graft-versus-host disease (GVHD) in NSG mice treated with A2+ human PBMCs. In most cases, these cells suppressed the xenogeneic GvHD progression as much as natural CD25+CD127- Tregs did.

Intraoperative bladder visualization by indocyanine green filling and subsequent washout in endoscopic hysterectomy: ICG-Washout method.

INTRODUCTION: Despite a potential risk of bladder injury in laparoscopic hysterectomy (LH) and robot-assisted LH (RaLH), an intraoperative method for delineating the entire bladder with indocyanine green (ICG) has not been established. METHODS: We conducted a preliminary experiment using porcine bladders to verify the appropriate amount of ICG for intraoperative bladder visualization. Afterward, intraoperative bladder visualization was tried in LH and RaLH in two patients suspected of having adhesions around the bladder after previous abdominal surgery. RESULTS: Although near-infrared (NIR) fluorescence was well observed through the wall of the porcine bladder filled with ICG solution at a concentration of 0.024 mg/mL, the subsequent replacement of the ICG solution with saline made the NIR fluorescence brighter. In both patients, the bladder was successfully delineated by NIR fluorescence after filling the bladder with ICG solution and the subsequent washout with saline. CONCLUSION: The ICG-Washout method for locating the bladder by NIR fluorescence could be useful in LH and RaLH.

Outcomes of Cessation of Nucleos(t)ide Analog Administration on Hepatitis B Virus Reactivation after Allogeneic Hematopoietic Stem Cell Transplantation: A Nationwide Retrospective Study.

Monitoring of hepatitis B virus (HBV)-DNA and HBV-DNA-guided preemptive therapy using nucleos(t)ide analogs (NAs) are recommended to prevent the development of hepatitis due to HBV reactivation after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in recipients with resolved HBV infection. However, little is known about the appropriate duration of NA treatment and the effect of NA cessation on the recurrence of HBV reactivation. This study aimed to clarify the consequences of NA cessation in allo-HSCT recipients with resolved HBV infection who experienced HBV reactivation following transplantation. We retrospectively reviewed the clinical records of recipients with resolved HBV infection (hepatitis B surface antigen [HBsAg]-negative, anti-HBc-positive) before allo-HSCT who had been diagnosed with HBV reactivation (HBsAg-positive and/or HBV-DNA detectable) after allo-HSCT between January 2010 and December 2020. A total of 72 patients from 16 institutions were registered (median age, 60 years; age range, 27 to 73 years; 42 males and 30 females). The day of initial HBV reactivation ranged from day 10 to day 3034 after allo-HSCT (median, 513 days). Anti-HBs were lost in >80% of the patients at the time of HBV reactivation. All 72 patients received preemptive NAs, and no fatal HBV reactivation-related hepatitis was observed. HBV-DNA without hepatitis was continuously detected in 5 patients during the follow-up period. Administration of NAs was discontinued in 24 of 72 patients (33%) by physician decision. Second HBV reactivation occurred in 11 of the 24 patients (46%) in whom administration of NAs was discontinued. The duration of NA treatment did not differ significantly between patients with or without second HBV reactivation. The frequency of further HBV reactivation tended to be lower in patients with an anti-HBs titer of >10 mIU/mL at the time of NA cessation. Multiple reactivations of HBV after NA cessation was common in patients with HBV reactivation who underwent allo-HSCT despite the long duration of NAs. Careful monitoring of HBV-DNA is important even after the discontinuation of NAs in the case with HBV reactivation after allo-HSCT, because multiple reactivations could occur. Active immunization by HB vaccine might be effective for suppressing further HBV reactivation after cessation of NAs.

A novel Foley catheter made of high-intensity near-infrared fluorescent silicone rubber for image-guided surgery of lower rectal cancer.

BACKGROUND: Urethral injury occurs in 1-6 % of male cases during minimally invasive surgery of lower rectal cancer. A Foley catheter emitting near-infrared (NIR) fluorescence of sufficient intensity has been expected to locate the urethra during image-guided surgery. Although it has been difficult to impart NIR fluorescent properties to biocompatible thermosetting polymers, we have recently succeeded in developing a NIR fluorescent compound for silicone rubber and a NIR fluorescent Foley catheter (HICARL). Here, we evaluated its NIR fluorescence properties and visibility performance using porcine anorectal isolation specimens. METHODS: The HICARL catheter was made of a mixture of solid silicone rubber and a NIR fluorescent compound that emits fluorescence with a wavelength of 820-880 nm, while a conventional transparent Foley catheter was made of solid silicone rubber only. As a standard for comparison of the intensity of NIR fluorescence, a transparent Foley catheter the lumen of which was filled with a mixture of indocyanine green (ICG) and human plasma was used. As a comparison to assess the visibility performance of the HICARL catheter, a transparent Foley catheter into which a commercially available NIR fluorescent polyurethane ureteral catheter (NIRC) was placed was used. RESULTS: A NIR fluorescence quantitative imaging analysis revealed that the Foley-NIRC catheter and the HICARL catheter emitted 3.42 ± 0.42 and 6.43 ± 0.07 times more fluorescence than the Foley-ICG catheter, respectively. The location of the HICARL catheter placed in the anorectum with a wall thickness of 3.8 ± 0.1 mm was clearly delineated in its entirety by NIR fluorescence, while that of the Foley-NIRC catheter was faintly or only partially visible. CONCLUSIONS: The HICARL catheter emitting NIR fluorescence of sufficient intensity is a promising and easy-to-use tool for urethral visualization during image-guided surgery of lower rectal cancer.