Infusions of Epstein–Barr virus-specific cytotoxic T lymphocytes as post-remission therapy in high-risk post-transplant lymphoproliferative disorder patients: report of two cases

Adoptive Immune Effector Cell Therapies in Cancer and Solid Organ Transplantation: A Review

Cancer is one of the most devastating complications of kidney transplantation and constitutes one of the leading causes of morbidity and mortality among solid organ transplantation (SOT) recipients. Immunosuppression, although effective in preventing allograft rejection, inherently inhibits immune surveillance against oncogenic viral infections and malignancy. Adoptive cell therapy, particularly immune effector cell therapy, has long been a modality of interest in both cancer and transplantation, though has only recently stepped into the spotlight with the development of virus-specific T-cell therapy and chimeric antigen receptor T-cell therapy. Although these modalities are best described in hematopoietic cell transplantation and hematologic malignancies, their potential application in the SOT setting may hold tremendous promise for those with limited therapeutic options. In this review, we provide a brief overview of the development of adoptive cell therapies with a focus on virus-specific T-cell therapy and chimeric antigen receptor T-cell therapy. We also describe the current experience of these therapies in the SOT setting as well as the challenges in their application and future directions in their development.

EBV-specific cytotoxic T lymphocytes for refractory EBV-associated post-transplant lymphoproliferative disorder in solid organ transplant recipients: a systematic review

The use of Epstein-Barr virus-specific cytotoxic T lymphocytes (EBV-CTLs) in adoptive immunotherapy in hematopoietic stem cell transplantation (HSCT) patients with post-transplantation lymphoproliferative disorder (PTLD) has demonstrated safety and effectiveness. EBV-CTLs might also be the effective treatment of refractory PTLD of solid organ transplantation (SOT) recipients. Two independent assessors searched Pubmed, Embase, Cochrane Library, and Web of Science from their inception to November 2020. Eleven studies with 76 patients (42, 55% male) were included. We extracted the data and completed the quality assessments. Most of the studies were from Europe and the USA. Liver and kidney transplantation accounted for most of the transplant types. Thirty-five (46.1%) patients were diagnosed with monomorphic PTLD, and B lymphocyte type was the most common. All the patients received primary treatment for PTLD while it was ineffective. CTLs included autologous EBV-CTLs (15/76, 22%) and HLA-matched third-party EBV-CTLs (61/76, 78%). The response rate for EBV-CTL treatment of refractory PTLD was 66%. Of 50 patients, 36 achieved complete remission and 14 achieved partial remission. EBV-DNA level decreased in 39 patients. Adverse reactions were rare and mild. We conclude that adoptive therapy with EBV-specific CTLs is safe, well-tolerated, and effective in PTLD.

Management of Epstein-Barr virus-related post-transplant lymphoproliferative disorder after allogeneic hematopoietic stem cell transplantation

Epstein–Barr virus-related post-transplant lymphoproliferative disorder (EBV-PTLD) is a rare but life-threatening complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). T-cell immunodeficiency after transplantation and EBV primary infection/reactivation play major roles in the pathogenesis. Unspecific clinical manifestations make the diagnosis difficult and time consuming. Moreover, this fatal disease usually progresses rapidly, and leads to multiple organ dysfunction or death if not treated promptly. Early diagnosis of EBV-DNAemia or EBV-PTLD generally increases the chances of successful treatment by focusing on regular monitoring of EBV-DNA and detection of symptomatic patients as early as possible. Rituximab ± reduction of immunosuppression (RI) is currently the first-line choice in preemptive intervention and targeted treatment. Unless patients are suffering from severe graft versus host disease (GvHD), it is better to combine rituximab with RI. Once a probable diagnosis is made, the first-line treatment should be initiated rapidly, along with, or ahead of, biopsy, although histopathologic confirmation is requisite. In addition, EBV-specific cytotoxic T lymphocytes (EBV-CTLs) or donor lymphocyte infusion (DLI) has shown promise in cases of suboptimal response. Chemotherapy ± rituximab might lend more opportunities to refractory/relapsed patients, who might also benefit from ongoing clinical trials. Herein, we discuss our clinical experience in detail based on the current literature and our five cases.

Prevention and therapy of viral infections in patients with solid organ transplantation

Solid organ transplantation (SOT) is the best treatment option for end-stage organ disease. The number of SOT procedures has been steadily increasing worldwide during the past decades. This trend has been accompanied by the continuous incorporation of new antimicrobial drugs and by the refinement of strategies aimed at minimizing the risk of opportunistic infection. Nonetheless, viral infections, which can occur at any stage of the post-transplant period, remain a clinical challenge that negatively impacts both patient and graft outcomes. This review offers an overview of the most relevant viral infections in the SOT population, with a focus on herpesviruses (cytomegalovirus, Epstein-Barr virus, varicella-zoster virus, and herpes simplex virus 1 and 2) and polyomaviruses (human BK polyomavirus). In addition, the currently recommended prophylactic and treatment approaches are summarized, as well as the new antiviral agents in different phases of clinical development.

Malignancy after lung transplantation

Lung transplantation is an established therapeutic option for selected patients with advanced lung diseases. As early outcomes after lung transplantation have improved, chronic medical illnesses have emerged as significant obstacles to long-term survival. Among them is post-transplant malignancy, currently representing the 2^nd most common cause of death 5–10 years after transplantation. Chronic immunosuppressive therapy and resulting impairment of anti-tumor immune surveillance is thought to have a central role in cancer development after solid organ transplantation (SOT). Lung transplant recipients receive more immunosuppression than other SOT populations, likely contributing to even higher risk of cancer among this group. The most common cancers in lung transplant recipients are non-melanoma skin cancers, followed by lung cancer and post-transplant lymphoproliferative disorder (PTLD). The purpose of this review is to outline the common malignancies following lung transplant, their risk factors, prognosis and current means for both prevention and treatment.