Beyond cancer treatment - a review of total lymphoid irradiation for heart and lung transplant recipients

Lymphocyte Depleting and Modulating Therapies for Chronic Lung Allograft Dysfunction

Chronic lung rejection, also called chronic lung allograft dysfunction (CLAD), remains the major hurdle limiting long-term survival after lung transplantation, and limited therapeutic options are available to slow the progressive decline in lung function. Most interventions are only temporarily effective in stabilizing the loss of or modestly improving lung function, with disease progression resuming over time in the majority of patients. Therefore, identification of effective treatments that prevent the onset or halt progression of CLAD is urgently needed. As a key effector cell in its pathophysiology, lymphocytes have been considered a therapeutic target in CLAD. The aim of this review is to evaluate the use and efficacy of lymphocyte depleting and immunomodulating therapies in progressive CLAD beyond usual maintenance immunosuppressive strategies. Modalities used include anti-thymocyte globulin, alemtuzumab, methotrexate, cyclophosphamide, total lymphoid irradiation, and extracorporeal photopheresis, and to explore possible future strategies. When considering both efficacy and risk of side effects, extracorporeal photopheresis, anti-thymocyte globulin and total lymphoid irradiation appear to offer the best treatment options currently available for progressive CLAD patients. SIGNIFICANCE STATEMENT: Effective treatments to prevent the onset and progression of chronic lung rejection after lung transplantation are still a major shortcoming. Based on existing data to date, considering both efficacy and risk of side effects, extracorporeal photopheresis, anti-thymocyte globulin, and total lymphoid irradiation are currently the most viable second-line treatment options. However, it is important to note that interpretation of most results is hampered by the lack of randomized controlled trials.

Development of Total Lymphoid Irradiation (TLI)-Dedicated Shielding and Image-Guided System and Dose Evaluation Using 3D-Printed Rat Phantom

Purpose

The purpose of this study is to propose a technique for delivering accurate doses in an image-guided system by developing an experimental setup optimized for total lymphoid irradiation (TLI) in rat lung transplantation.

Materials and Methods

In this study, a position-controlled shielding system was developed, and the dose was quantitatively evaluated using a 3D rat phantom and Gafchromic EBT3 film. In addition, we made our own image-guided system that allows the position of the rat and the shielding system to be confirmed during TLI.

Results

As a result of using the position-controlled shielding system, it was found that the doses to the head and lungs were reduced by 93.1 and 87.4%, respectively, of the prescribed doses. In addition, it was shown that the position of the shielding system can be easily confirmed by using the image guidance system.

Conclusion

A shielding apparatus that can control dose delivery according to the size of the rat can optimize the dose for TLI in rat lung transplantation.

Safety and efficacy of a nonmyeloablative pretransplant conditioning regimen using total lymphoid irradiation with volumetric modulated arc therapy in healthy dogs: A pilot study

Allogeneic hematopoietic cell transplantation (HCT) has been an effective treatment for human patients with haematological malignancies (Baron & Storb, 2006; Bair et al., 2020; Copelan et al., 2019). However, the optimal pretransplant conditioning treatment is unclear in canine allogeneic HCT. This pilot study aimed to evaluate the safety and efficacy of total lymphoid irradiation (TLI) with volumetric modulated arc therapy (VMAT) for a nonmyeloablative HCT conditioning. Six healthy dogs were treated with 8 or 12 Gy TLI using VMAT. Haematological and physical changes were recorded over 8 weeks. To assess the effect of peripheral lymphocyte condition, lymphocyte subset and proliferative ability were examined. At the end of the experiment, necropsy was performed. All dogs showed mild‐to‐moderate neutropenia and thrombocytopenia, and these haematological changes resolved spontaneously. One dog treated with 8 Gy TLI developed transient cutaneous infection. No major complication was seen in the other seven dogs. Myelocytes and erythroblast cytopenia of bone marrow were detected in two dogs treated with 12 Gy TLI. This study is the first report of TLI using VMAT in dogs, and results suggest that this regimen is a feasible nonmyeloablative treatment.

TLI in pediatric patients

PURPOSE

Hematopoietic progenitor cell transplantation (HSCT) is a procedure used in different hematological diseases as part of the curative treatment, so the investigators propose a system of conditioning of reduced intensity based on total lymphoid irradiation (TLI) as an alternative to the classic total body irradiation (TBI) followed by haploidentical transplantation in patients compatible with a single HLA haplotype, as an alternative to patients who do not have an HLA compatible donor.

MATERIALS AND METHODS

A cohort of 25 patients with hematological disease underwent haploidentical HSCT from February 2015 to May 2018, conditioned with TLI from day - 10 (2-4 days of treatment) followed by thiotepa (5 mg/kg/12 h) and melphalan (70 mg/m²/day) prior to HSCT and prophylaxis with ciclosporin (1.5 mg/kg/12 h). 2 Gy/fraction was administered to complete 8 Gy with IMRT and VMAT technique.

RESULTS

12% rejection of the transplant was obtained with acute GVHD < II (48%) and chronic GVHD 12%. No acute toxicity was recorded in irradiated patients and 56% survival of patients at the end of follow-up.

CONCLUSION

Conditioning the haploidentical transplant with TLI, IMRT, and VMAT techniques compared with TBI and RT3D-C techniques is a feasible technique that helps inducing the necessary immunosuppression in patients with a high risk of graft rejection, minimal adverse effects, low incidence of GVHD, and high survival rate.

Tumor necrosis factor-related apoptosis-inducing ligand additive with Iodine-131 of inhibits non-small cell lung cancer cells through promoting apoptosis

Non-small-cell lung cancer (NSCLC) accounts for ~80% of human lung cancer cases and is the most common cause of cancer-associated mortality worldwide. Reports have indicated that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and Iodine-131 (I-131) can induce tumor cell apoptosis. The purpose of the present study was to investigate the additive efficacy of TRAIL and I-131 on NSCLC cells. The present study demonstrated that additive treatment of TRAIL and I-131 (TRAIL-I-131) significantly inhibited the growth and aggressiveness of NSCLC cells compared with single TRAIL or I-131 treatment. Results demonstrated that TRAIL-I-131 treatment induced apoptosis of NSCLC cells, with western blot analysis confirming that TRAIL-I-131 treatment increased proapoptotic Bad and Bax expression levels, while antiapoptotic Bcl-2 and Bcl-w protein levels were decreased in NSCLC cells. The present study demonstrated that TRAIL-I-131 treatment inhibited vascular endothelial growth factor (VEGF) and activator protein-1 (AP-1) in NSCLC cells. Potential mechanism analyses identified that TRAIL-I-131 treatment induced apoptosis of NSCLC cells through caspase-9 activation. In vivo assays revealed that TRAIL-I-131 treatment significantly inhibited NSCLC tumor growth and increased apoptotic bodies in tumor tissues. Immunohistology demonstrated that caspase-9 was upregulated and VEGF was downregulated in tumor tissues in TRAIL-I-131-treated tumors. In conclusion, these results indicate that TRAIL combined with I-131 promoted apoptosis of NSCLC through caspase-9 activation, which may be a promising anticancer therapeutic schedule for the treatment of NSCLC.