Solid organ transplantation following allogeneic haematopoietic cell transplantation: experience from a referral organ transplantation center and systematic review of literature

New insights in immunomodulation for intestinal transplantation

Tolerance is the Holy Grail of solid organ transplantation (SOT) and remains its primary challenge since its inception. In this topic, the seminal contributions of Thomas Starzl at Pittsburgh University outlined foundational principles of graft acceptance and tolerance, with chimerism emerging as a pivotal factor. Immunologically, intestinal transplantation (ITx) poses a unique hurdle due to the inherent characteristics and functions of the small bowel, resulting in increased immunogenicity. This necessitates heavy immunosuppression (IS) while IS drugs side effects cause significant morbidity. In addition, current IS therapies fall short of inducing clinical tolerance and their discontinuation has been proven unattainable in most cases. This underscores the unfulfilled need for immunological modulation to safely reduce IS-related burdens. To address this challenge, the Leuven Immunomodulatory Protocol (LIP), introduced in 2000, incorporates various pro-tolerogenic interventions in both the donor to the recipient, with the aim of facilitating graft acceptance and improving outcome. This review seeks to provide an overview of the current understanding of tolerance in ITx and outline recent advances in this domain.

Successful Kidney and Hematopoietic Stem Cell Transplantation for Malignant Lymphoma from Different Donors: A Case Report and Literature Review

There are particularly few reports on kidney transplantation after hematopoietic stem cell transplantation (HSCT) for malignant lymphoma, and none of the cases reported a favorable outcome in patients who received kidney transplantation from a different donor to HSCT. In this report, we describe the first case of kidney transplantation from a different donor to HSCT with a successful outcome. Furthermore, we reviewed the previously reported cases. A 59-year-old female patient received an HSCT from her younger brother after chemotherapy for malignant lymphoma. After HSCT, she did not have graft-versus-host disease (GVHD) requiring maintenance treatment. The patient developed chronic kidney disease requiring kidney replacement therapy, probably due to drug toxicity or cardio-renal syndrome. At age 65, she underwent an ABO-compatible, HLA-A, -B, -DR 5/6 mismatched kidney transplantation from her husband. Immunosuppressive therapy with tacrolimus, mycophenolate mofetil, methylprednisolone, and basiliximab was administered. The patient had urinary tract infections at 7 days, 9 weeks, and 4 months after kidney transplantation, and cytomegalovirus antigenemia at 9 weeks after kidney transplantation, which improved with antibiotic and valganciclovir, respectively. When each infection occurred, we weakened immunosuppressive therapy. Four years after kidney transplantation, the patient is in good clinical condition with a serum creatinine of 1.2 mg/dL, without critical infection or malignancy. In this case, we believe that it was important to optimize the immunosuppressive therapy. In addition, from a review of previous cases, it seemed important that there was no GVHD requiring maintenance therapy in order to prevent excessive immunosuppression.

Liver Transplantation After Hematopoietic Stem Cell Transplant for the Treatment of Sickle Cell Disease: A Case Report

Sickle cell anemia is the most common of the hemoglobinopathies, in which the abnormal hemoglobin formed in deoxygenation states undergoes a polymerization process with consequent erythrocyte deformation and vaso-occlusive events. The need for multiple blood transfusions, prolonged ineffective erythropoiesis, hemolysis, and increased iron absorption can cause iron overload in the liver, leading to liver fibrosis. Hematopoietic stem cell transplantation (HSCT) is currently the only treatment with a curative potential for this disease and can establish normal complete or partial donor-derived erythropoiesis and stabilize or restore function in affected organs, preventing further deterioration of function. However, it does not reverse preexisting liver fibrosis and siderosis. One of the possible complications of patients who undergo HSCT is chronic liver disease, which has a multifactorial cause, with iron overload being an important factor. In the long term, the prevalence of chronic liver disease in HSCT patients, including cirrhosis and its complications, can be significant. Solid organ transplantation after allogeneic hematopoietic cell transplantation for end-organ failure remains a very rare event. It may offer a valuable treatment strategy in selected recipients, although it is associated with significant morbidity and mortality. We report the case of a patient with sickle cell anemia who underwent HSCT and developed severe liver dysfunction requiring liver transplantation 13 years after the procedure. We found no previous report in the literature of orthotopic liver transplant after HCT for the treatment of sickle cell disease.

Case Report: Liver as a Source of Hematopoietic Stem Cells After Liver Transplantation Following Hematopoietic Stem Cell Transplantation

We report a child with Fanconi anemia who, after hematopoietic stem cell transplantation (HSCT) complicated by acute graft-versus-host disease (GVHD), underwent orthotopic liver transplantation (OLT). Approximately 1 month after OLT, the presence of third-party genetic material from the liver donor was noted and in the next few weeks, the chimerism assessment revealed 100% liver donor leukocytes in the peripheral blood. The rapidly progressing GVHD with gut involvement resulted in patient's death 6 months after OLT. The liver can act as a clinically significant source of hematopoietic stem cells, and the liver donor's young age must be emphasized as potentially predisposing to this phenomenon. Transfer of OLT hematopoietic stem cells may not have clinical significance unless the patient is not immunocompetent or develops liver-transplantation associated GVHD, that can result in lymphocyte mediated elimination of original hematopoiesis. Patients with preexisting immunity disorder (such as primary or secondary immunodeficiency) might require intensified immunosuppressive therapy in peritransplant period as a prevention of liver-transplantation associated GVHD. Close monitoring of hematopoietic chimerism after OLT is warranted in patients at risk, because cytopenia or OLT hematopoiesis can reflect subclinical GVHD and further studies are necessary to elucidate this phenomenon.

ABO-Incompatible Kidney Transplantation After Bone Marrow Transplantation: A Case Report

Many studies have been made on ABO-compatible kidney transplants following hematopoietic stem cell transplantation. However, there have been few reports on ABO-incompatible kidney transplantation following hematopoietic stem cell transplantation (HSCT). We report on the case of a successful ABO-incompatible kidney transplantation with high titers after bone marrow transplantation experienced no infectious episodes. The patient was a 38-year-old man with end-stage kidney disease resulting from interstitial nephritis induced by drug toxicity or graft-vs-host disease (GVHD). He had received allogeneic bone marrow transplantation from a human leukocyte antigen-identical unrelated donor to treat chronic myelogenous leukemia. The patient with high anti-B antibody titers (IgM 1:1024 IgG 1:256) received a desensitization protocol consisting of 2 doses of rituximab and 5 courses of plasmapheresis. The patient had prolonged depletion of circulating B cells 2 years after the transplant and was infected with cytomegalovirus viremia, pneumocystis jiroveci pneumonia, and adenovirus urinary tract infection at 2, 3, and 17 months post-transplant, respectively. Currently, at 6 years after his transplant, the patient has had no rejection and is in good clinical condition with only mild renal insufficiency. Our results suggest that ABO-incompatible kidney transplantation may be an effective renal replacement therapy for patients with end-stage kidney disease after HSCT, but desensitization in combination with immunosuppressants could lead to a state of over-immunosuppression, causing various infections.

Developments and translational relevance for the canine haematopoietic cell transplantation preclinical model

The development of safe and reliable haematopoietic cell transplantation (HCT) protocols to treat human patients with malignant and non-malignant blood disorders was highly influenced by preclinical studies obtained in random-bred canines. The surmounted barriers included recognizing the crucial importance of histocompatibility matching, establishing long-term donor haematopoietic cell engraftment, preventing graft-vs-host disease and advancing effective conditioning and post-grafting immunosuppression protocols, all of which were evaluated in canines. Recent studies have applied the tolerance inducing potential of HCT to solid organ and vascularized composite tissue transplantation. Several advances in HCT and tolerance induction that were first developed in the canine preclinical model and subsequently applied to human patients are now being recruited into veterinary practice for the treatment of malignant and non-malignant disorders in companion dogs. Here, we review recent HCT advancements attained in the canine model during the past 15 years.

Haploidentical hematopoietic cell and kidney transplantation for hematological malignancies and end-stage renal failure

At Massachusetts General Hospital, we pioneered simultaneous hematopoietic cell (HCT)/kidney transplantation from HLA-identical related donors for the treatment of hematological malignancies with end-stage renal failure. We have now extended this to HLA-haploidentical donors in a pilot trial. Six recipients, 5 of whom were conditioned with fludarabine, cyclophosphamide, and total-body irradiation, underwent combined HCT/kidney transplantation from haploidentical donors; graft-versus-host disease (GVHD) prophylaxis included post-HCT cyclophosphamide, tacrolimus, and mycophenolate mofetil. One patient died as a result of complications of fludarabine neurological toxicity. No neurological toxicity was observed in subsequent patients who received lower fludarabine doses and more intense postfludarabine dialysis. There were no cases of grade 2 to 4 acute GVHD and 1 case of moderate chronic GVHD by 12 months. One patient experienced relapse of multiple myeloma at 30 months after HCT and died 4 years posttransplantation. Overall, 4 of 6 patients remain alive, without disease relapse and with long-term renal rejection-free survival. This trial was registered at www.clinicaltrials.gov as #NCT01758042.