sirolimus and Epstein-Barr-Virus-Infections

Epstein-Barr virus (EBV)-associated postallogeneic stem cell transplantation (SCT) lymphoproliferative disorder (PTLD) is often life threatening. The risk of EBV reactivation is highest in older patients, T cell-depleted SCT (in vivo or vitro), and in unrelated or mismatched SCT. Cumulative numbers of patients with EBV reactivation and PTLD are rising as more patients at high risk for EBV reactivation and PTLD are receiving allo-SCT. Novel but easily applicable strategies are needed to prevent EBV reactivation and PTLD to serve the needs of the increasingly enlarging population of high-risk SCT recipients across the globe.

Topics: Antibodies, Monoclonal, Murine-Derived; Antineoplastic Agents; DNA, Viral; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Humans; Immunocompromised Host; Immunosuppression Therapy; Lymphoproliferative Disorders; Risk; Rituximab; Sirolimus; Stem Cell Transplantation; T-Lymphocytes, Cytotoxic; Transplantation, Homologous; Viral Load; Virus Activation

To summarize recent advances that contribute to our understanding of the pathobiology of Epstein-Barr virus (EBV)-associated posttransplant lymphoproliferative disease (PTLD), the host immune response to virally infected B cells, and the molecular basis for the effects of mammalian target of rapamycin inhibitors on EBV+ B-cell lymphomas.. Cytogenetic and genomic analyses support the concept that the underlying biology of EBV-associated PTLD is complex. Transplant recipients can generate and maintain significant populations of EBV-specific CD8+ memory T cells but the function of these cells may be impaired. EBV invokes multiple strategies to subvert and evade the host immune response. The phosphoinositide-3 kinase/Akt/mammalian target of rapamycin signal transduction pathway is a nexus for growth and survival signals in PTLD-associated EBV+ B-cell lymphomas.. Multiple factors influence the development of EBV-associated PTLD including the host immune response to EBV, virally induced effects on the infected cell and the host immune system, and the type and intensity of immunosuppression.

Topics: Animals; CD8-Positive T-Lymphocytes; Epstein-Barr Virus Infections; Graft Survival; Herpesvirus 4, Human; Humans; Immunologic Memory; Immunosuppressive Agents; Lymphoma, B-Cell; Lymphoproliferative Disorders; Organ Transplantation; Protein Kinases; Signal Transduction; Sirolimus; T-Lymphocytes, Regulatory; TOR Serine-Threonine Kinases

The natural history of EBV and CMV reactivation and the potential for serious complications following antibody-based immunosuppressive treatment for bone marrow failure syndromes in the absence of transplantation is not known. We monitored blood for EBV and CMV reactivation by polymerase chain reaction (PCR) weekly in 78 consecutive patients (total of 99 immunosuppressive courses) with aplastic anemia. Four regimens were studied: (1) HC, horse ATG/cyclosporine; (2) HCS, horse ATG/CsA/sirolimus; (3) RC, rabbit ATG/CsA; and (4) CP, alemtuzumab. There were no cases of EBV or CMV disease, but EBV reactivation occurred in 82 (87%) of 94 and CMV reactivation in 19 (33%) of 57 seropositive patients after starting immunosuppression. The median peak EBV copies were higher in the RC group when compared with HC, HCS, and alemtuzumab (P < .001). The median duration of PCR positivity for EBV was higher in the RC group compared with HC, HCS, and alemtuzumab (P = .001). Subclinical reactivation of both EBV and CMV is common and nearly always self-limited in patients with bone marrow failure receiving immunosuppression; different regimens are associated with different intensity of immunosuppression as measured by viral load and lymphocyte count; and viral reactivation patterns differ according to immunosuppressive regimens.

Topics: Adolescent; Adult; Aged; Alemtuzumab; Anemia, Aplastic; Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antibodies, Neoplasm; Antilymphocyte Serum; Antineoplastic Agents; Child; Child, Preschool; Cyclosporine; Cytomegalovirus; Cytomegalovirus Infections; DNA, Viral; Epstein-Barr Virus Infections; Female; Herpesvirus 4, Human; Horses; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Male; Middle Aged; Monitoring, Physiologic; Polymerase Chain Reaction; Rabbits; Sirolimus; Time Factors; Virus Activation

Belatacept is employed alongside calcineurin inhibitor (CNI) therapy to prevent graft rejection in kidney transplant patients who are Epstein-Barr virus (EBV) seropositive. Preliminary data suggested that rates of post-transplant lymphoproliferative disorder (PTLD) were higher in individuals treated with belatacept compared to CNI therapy alone.. The records of 354 adults who underwent kidney only transplantation from January 2015 through September 2021 at one medical center were evaluated. Patients underwent treatment with either low-doses of mycophenolate, tacrolimus and sirolimus (B. Non-belatacept (MMF, tacrolimus and sirolimus) and belatacept-based (MMF, tacrolimus and belatacept) regimens do not appear to pose any increased risk of early onset PTLD. Both cohorts benefited from low rates of rejection, malignancy, mortality and graft failure. Recipients will continue to be monitored as PTLD can manifest as a long-term complication.

Topics: Abatacept; Adult; Calcineurin Inhibitors; Epstein-Barr Virus Infections; Graft Rejection; Graft Survival; Herpesvirus 4, Human; Humans; Immunosuppressive Agents; Kidney Transplantation; Lymphoproliferative Disorders; Neoplasms; Sirolimus; Tacrolimus

Post-transplant lymphoproliferative disorder is a life-threatening complication of immunosuppression following transplantation mediated by failure of T cells to control Epstein-Barr virus (EBV)-infected and transformed B cells. Typically, a modification or reduction of immunosuppression is recommended, but insufficiently defined thus far. In order to help delineate this, we characterized EBV-antigen-specific T cells and lymphoblastoid cell lines from healthy donors and in patients with a kidney transplant in the absence or presence of the standard immunosuppressants tacrolimus, cyclosporin A, prednisolone, rapamycin, and mycophenolic acid. Phenotypes of lymphoblastoid cell-lines and T cells, T cell-receptor-repertoire diversity, and T-cell reactivity upon co-culture with autologous lymphoblastoid cell lines were analyzed. Rapamycin and mycophenolic acid inhibited lymphoblastoid cell-line proliferation. T cells treated with prednisolone and rapamycin showed nearly normal cytokine production. Proliferation and the viability of T cells were decreased by mycophenolic acid, while tacrolimus and cyclosporin A were strong suppressors of T-cell function including their killing activity. Overall, our study provides a basis for the clinical decision for the modification and reduction of immunosuppression and adds information to the complex balance of maintaining anti-viral immunity while preventing acute rejection. Thus, an immunosuppressive regime based on mTOR inhibition and reduced or withdrawn calcineurin inhibitors could be a promising strategy for patients with increased risk of or manifested EBV-associated post-transplant lymphoproliferative disorder.

Topics: Calcineurin; Cyclosporine; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Lymphoproliferative Disorders; MTOR Inhibitors; Mycophenolic Acid; Prednisolone; Sirolimus; Tacrolimus; TOR Serine-Threonine Kinases

Kidney transplant outcomes are limited by toxicities associated with calcineurin inhibitors and steroids. This trial was conducted to determine whether a costimulation blockade (CoB)-based regimen could achieve acceptable long-term outcomes and graft survival could be maintained solely with CoB. Forty patients underwent alemtuzumab induction followed by belatacept and sirolimus maintenance therapy. Patients were offered weaning to belatacept monotherapy after 1 year and followed for 5 years. Five-year patient and graft survival rates were 100% and 95%, respectively. Graft function remained stable with a mean estimated glomerular filtration rates of 67 ± 21 and 71 ± 19 at 36 and 60 months, respectively. There was no clinical rejection in the first year; subclinical rejection was detected by protocol biopsy in 4 patients. Twelve patients were successfully weaned to belatacept monotherapy. Cytomegalovirus and Epstein-Barr virus reactivations were well controlled, but 9 patients experienced transient BK viremia during the first year. Alemtuzumab produced profound lymphopenia followed by gradual T cell and more rapid B cell reconstitution to a repertoire deviated toward naïve cells with increased regulatory T cells. This regimen effectively prevents allograft rejection without using steroids or calcineurin inhibitors, enriches for naïve cells susceptible to control with CoB, and permits control of rejection with belatacept monotherapy in selected patients.

Topics: Abatacept; Alemtuzumab; Epstein-Barr Virus Infections; Follow-Up Studies; Graft Rejection; Graft Survival; Herpesvirus 4, Human; Humans; Immunosuppressive Agents; Kidney Transplantation; Sirolimus

Epstein-Barr virus (EBV) is a widely prevalent pathogen currently infecting over 90% of the human population and is associated with various lymphomas and carcinomas. Lytic replication of EBV is regulated by the expression of the immediate-early genes BZLF1 and BRLF1. In B lymphocytes, BZLF1 transcripts have been shown to be processed to a fully spliced form, as well as zDelta, a spliced variant containing only the first and third exons. While splice variants have been reported in nasopharyngeal carcinoma biopsies, alternative splicing of BZLF1 in EBV-positive epithelial cell lines has not yet been characterized. In this study, we identified the consistent expression of three distinct BZLF1 transcripts in the EBV-positive epithelial cell lines D98/HR1, AGS-BDneo, and AGS-BX1. These BZLF1 transcripts consisted of not only the normally spliced variant but also a completely unspliced and a spliced variant containing exons one and three only. In contrast, we detected only the normally spliced version of the BZLF1 transcript in B-cell lines (B95-8, IM-9, Raji and Daudi). Previous work has also demonstrated that inhibition of the mTOR pathway, via rapamycin, altered total levels of BZLF1 transcripts. We examined the production of specific transcript variants under rapamycin treatment and found that rapamycin alters the production of transcripts in a cell-type, as well as transcripts in variant-type, manners. The expression of these transcript variants may play a role in modulating the replication cycle of EBV within epithelial cells.

Topics: B-Lymphocytes; Cell Line; Epithelial Cells; Epstein-Barr Virus Infections; Gene Expression Regulation, Viral; Herpesvirus 4, Human; Humans; Promoter Regions, Genetic; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases; Trans-Activators; Virus Activation; Virus Latency

A 7-year-old boy with a history of low-risk acute lymphoblastic leukemia developed multiple intussusceptions shortly after the end of maintenance therapy. Explorative laparotomy showed >10 polyps in the small intestine. Histologic examination revealed intestinal smooth muscle sarcomas associated with Epstein-Barr virus. The patient recovered well after partial cuneiform resection of the largest polyps and treatment with sirolimus. This case report indicates that these tumors may arise even after moderate transient immunosuppression and that association with acute lymphoblastic leukemia is possible although rarely described. We discuss the potential benefit of the mTor/Akt signal inhibitors as treatment for these tumors.

Topics: Child; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Humans; Intestinal Neoplasms; Male; Muscle Neoplasms; Muscle, Smooth; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma; Sarcoma; Sirolimus

Topics: Allografts; Animals; B-Lymphocytes; Epstein-Barr Virus Infections; Female; Graft Rejection; Graft Survival; Heart Transplantation; Heterocyclic Compounds, 3-Ring; Humans; Inhibitory Concentration 50; Lymphoma, B-Cell; Lymphoproliferative Disorders; Male; Mice; Mice, Inbred C57BL; Mice, Inbred NOD; Mice, SCID; Neoplasm Transplantation; Organ Transplantation; Phosphoinositide-3 Kinase Inhibitors; Postoperative Complications; Proto-Oncogene Proteins c-akt; Purines; Quinazolinones; Sirolimus; TOR Serine-Threonine Kinases

Epstein-Barr virus-associated smooth-muscle tumors (EBV-SMTs) are unique and rare neoplasms described in immunocompromised patients. The case describes a nine-year-old female with a history of acute lymphoblastic leukemia with relapse and subsequent allogeneic bone marrow transplantation who presented with multiple EBV-SMTs of the liver. EBV utilizes the mammalian target of rapamycin (mTOR) pathway for tumor growth, and sirolimus, a mTOR inhibitor, has shown to result in a short-term response. We now report an extended treatment response with sirolimus in a pediatric patient with an EBV-SMT.

Topics: Bone Marrow Transplantation; Child; Epstein-Barr Virus Infections; Female; Herpesvirus 4, Human; Humans; Immunocompromised Host; Immunosuppressive Agents; Prognosis; Sirolimus; Smooth Muscle Tumor; TOR Serine-Threonine Kinases

The tetraspanin protein CD63 has been recently described as a key factor in extracellular vesicle (EV) production and endosomal cargo sorting. In the context of Epstein-Barr virus (EBV) infection, CD63 is required for the efficient packaging of the major viral oncoprotein latent membrane protein 1 (LMP1) into exosomes and other EV populations and acts as a negative regulator of LMP1 intracellular signaling. Accumulating evidence has also pointed to intersections of the endosomal and autophagy pathways in maintaining cellular secretory processes and as sites for viral assembly and replication. Indeed, LMP1 can activate the mammalian target of rapamycin (mTOR) pathway to suppress host cell autophagy and facilitate cell growth and proliferation. Despite the growing recognition of cross talk between endosomes and autophagosomes and its relevance to viral infection, little is understood about the molecular mechanisms governing endosomal and autophagy convergence. Here, we demonstrate that CD63-dependent vesicle protein secretion directly opposes intracellular signaling activation downstream of LMP1, including mTOR-associated proteins. Conversely, disruption of normal autolysosomal processes increases LMP1 secretion and dampens signal transduction by the viral protein. Increases in mTOR activation following CD63 knockout are coincident with the development of serum-dependent autophagic vacuoles that are acidified in the presence of high LMP1 levels. Altogether, these findings suggest a key role of CD63 in regulating the interactions between endosomal and autophagy processes and limiting cellular signaling activity in both noninfected and virally infected cells.

Topics: Autophagy; Cell Proliferation; Endosomes; Epstein-Barr Virus Infections; Exocytosis; Exosomes; HEK293 Cells; Herpesviridae; Herpesvirus 4, Human; Humans; Microscopy, Electron, Transmission; Protein Binding; Protein Transport; Secretory Vesicles; Signal Transduction; Sirolimus; Tetraspanin 30; Tetraspanins; TOR Serine-Threonine Kinases; Trehalose; Vacuoles; Viral Matrix Proteins; Virus Assembly

Heterozygous gain-of-function mutations in PI3K110δ lead to lymphadenopathy, lymphoid hyperplasia, EBV and cytomegalovirus viremia, and sinopulmonary infections.. The known role of natural killer (NK) cell function in the control of EBV and cytomegalovirus prompted us to investigate the functional and phenotypic effects of PI3K110δ mutations on NK cell subsets and cytotoxic function.. Mutations in patients were identified by using whole-exome or targeted sequencing. We performed NK cell phenotyping and functional analysis of patients' cells using flow cytometry, standard Cr. PI3K110δ mutations led to an altered NK cell developmental phenotype and cytotoxic dysfunction. Impaired NK cell cytotoxicity was due to decreased conjugate formation with susceptible target cells and abrogated activation of cell machinery required for target cell killing. These defects were restored partially after initiation of treatment with rapamycin in 3 patients.. We describe novel NK cell functional deficiency caused by PI3K110δ mutation, which is a likely contributor to the severe viremia observed in these patients. Rapamycin treatment partially restores NK cell function, providing a further rationale for its use in patients with this disease.

Topics: Cell Differentiation; Cells, Cultured; Class I Phosphatidylinositol 3-Kinases; Cytomegalovirus; Cytomegalovirus Infections; Cytotoxicity, Immunologic; Epstein-Barr Virus Infections; Exome Sequencing; Herpesvirus 4, Human; Heterozygote; Humans; Immunologic Deficiency Syndromes; Immunological Synapses; Immunophenotyping; Killer Cells, Natural; Lymphocyte Activation; Microscopy, Confocal; Mutation; Phosphatidylinositol 3-Kinases; Sirolimus; Viremia

A 27-year old caucasian male was diagnosed 2.7 years after kidney transplantation with Epstein-Barr virus (EBV)-associated smooth muscle tumors in liver and spleen. The reduction in immunosuppression and conversion from tacrolimus to sirolimus did not lead to a regression of the tumors. Additionally, the patient developed a cellular rejection of his renal allograft, which was successfully treated. A combined approach with stereotactic radiofrequency ablation (SRFA) and surgical resection was effective in the treatment of the tumors.

Topics: Adult; Epstein-Barr Virus Infections; Graft Rejection; Herpesvirus 4, Human; Humans; Immunocompromised Host; Immunosuppressive Agents; Kidney Transplantation; Liver; Male; Radiosurgery; Sirolimus; Smooth Muscle Tumor; Spleen; Tacrolimus; Treatment Outcome

Success after solid organ transplantation is dependent on the proper balance of immunosuppression to prevent rejection of the allograft while limiting the risk of developing infections and malignancy. We present a 9-year-old girl, remote from transplant, who presented with airway plaque after a change in immunosuppression to include the mTOR inhibitor sirolimus. Differential diagnosis included direct medication side effect, infection, and neoplasia.

Topics: Child; Epstein-Barr Virus Infections; Female; Graft Rejection; Heart Transplantation; Humans; Immunocompromised Host; Immunosuppressive Agents; Lymphoproliferative Disorders; Postoperative Complications; Sirolimus

The risks for transplant outcomes associated with baseline viral serostatus in kidney transplant recipients (KTR) on sirolimus have not been widely studied.. We performed a cohort-study of 61 590 adult KTR in 2000 to 2013. We used Cox regression models to determine the adjusted hazard ratio (aHR) of patient death, death-censored graft loss and posttransplant malignancy associated with the baseline serostatus (+ or -: hepatitis B core [HBc], hepatitis C virus [HCV], Epstein-Barr virus [EBV], or cytomegalovirus [CMV]) in KTR on sirolimus (SRL) + mycophenolate (MPA) or SRL + tacrolimus (Tac), relative to the control-regimen: Tac + MPA.. Compared with Tac + MPA, SRL + MPA, and SRL + Tac were associated with higher risks of 5-year mortality (aHR, 1.41; 95% CI, 1.23-1.60 and aHR, 1.59; 95% CI, 1.38-1.83, respectively) and death-censored graft loss (aHR, 1.41; 95% CI, 1.24-1.60 and aHR, 1.38; 95% CI, 1.21-1.57, respectively). In KTR with negative pretransplant EBV, CMV, HBc, or HCV serostatus, SRL + MPA not SRL + Tac was associated with a lower risk of posttransplant malignancy compared with control (aHR, 0.27; 95% CI, 0.10-0.72; aHR, 0.61; 95% CI, 0.43-0.88; aHR, 0.79; 95% CI, 0.64-0.97; and aHR, 0.80; 95% CI, 0.65-0.98, respectively, for SRL + MPA and aHR, 0.98: 95% CI, 0.52-1.80; aHR, 0.69; 95% CI, 0.46-1.06; aHR, 0.83; 95% CI, 0.66-1.06 and aHR, 0.85; 95% CI, 0.67-1.07, respectively, for SRL + Tac). In KTR with positive serostatus to any of the above viruses, SRL + MPA or SRL + Tac was not associated with a different malignancy risk compared with control.. Compared with Tac + MPA, SRL regimens were associated with higher risks for patient death and graft loss, although SRL + MPA was associated with a lower risk for posttransplant malignancy in kidney allograft recipients with negative pretransplant HBc, HCV, EBV, or CMV serology.

Topics: Adult; Allografts; Antibodies, Viral; Biomarkers; Chi-Square Distribution; Cytomegalovirus Infections; Drug Therapy, Combination; Epstein-Barr Virus Infections; Female; Graft Survival; Hepatitis B; Hepatitis C; Humans; Immunocompromised Host; Immunosuppressive Agents; Kidney Transplantation; Logistic Models; Male; Middle Aged; Multivariate Analysis; Neoplasms; Odds Ratio; Predictive Value of Tests; Proportional Hazards Models; Registries; Retrospective Studies; Risk Factors; Serologic Tests; Sirolimus; Time Factors; Treatment Outcome; United States

The p110δ subunit of phosphatidylinositol-3-OH kinase (PI(3)K) is selectively expressed in leukocytes and is critical for lymphocyte biology. Here we report fourteen patients from seven families who were heterozygous for three different germline, gain-of-function mutations in PIK3CD (which encodes p110δ). These patients presented with sinopulmonary infections, lymphadenopathy, nodular lymphoid hyperplasia and viremia due to cytomegalovirus (CMV) and/or Epstein-Barr virus (EBV). Strikingly, they had a substantial deficiency in naive T cells but an over-representation of senescent effector T cells. In vitro, T cells from patients exhibited increased phosphorylation of the kinase Akt and hyperactivation of the metabolic checkpoint kinase mTOR, enhanced glucose uptake and terminal effector differentiation. Notably, treatment with rapamycin to inhibit mTOR activity in vivo partially restored the abundance of naive T cells, largely 'rescued' the in vitro T cell defects and improved the clinical course.

Topics: Antibiotics, Antineoplastic; Cell Differentiation; Cells, Cultured; Cellular Senescence; Class I Phosphatidylinositol 3-Kinases; Cytomegalovirus Infections; Epstein-Barr Virus Infections; Female; Genes, Dominant; Germ-Line Mutation; Humans; Immunoblotting; Immunologic Deficiency Syndromes; Male; Pedigree; Phosphatidylinositol 3-Kinases; Phosphorylation; Proto-Oncogene Proteins c-akt; Sirolimus; T-Lymphocytes; TOR Serine-Threonine Kinases; Viremia

Epstein-Barr virus (EBV) infects B cells, as well as T cells and natural killer (NK) cells, and is associated with T or NK cell lymphoid malignancies. In various tumor cells, mTOR performs an essential function together with Akt with regard to cell growth. We investigated the effects of mTOR inhibitors on EBV-associated T- and NK-cell lymphomas.. We investigated the Akt/mTOR activation pathway in EBV-positive and -negative T- and NK-cell lines (SNT13, SNT16, Jurkat, SNK6, KAI3, and KHYG1). We evaluated the antitumor effects of mTOR inhibitors (rapamycin and its analogue, CCI-779) against these cell lines in culture and in a murine xenograft model that was established by subcutaneous injection of SNK6 cells into NOG mice.. All EBV-positive and -negative T- and NK-cell lines tested displayed activation of the Akt/mTOR pathway, and treatment with mTOR inhibitors suppressed mTOR activation. The inhibitors induced G1 cell-cycle arrest and inhibited cell proliferation in T- and NK-cell lines. Overall, T cell lines were more sensitive to rapamycin, but there were no significant differences between EBV-positive and -negative cell lines. Treatment with rapamycin did not affect lytic or latent EBV gene expression. Intraperitoneal treatment with CCI-779 significantly inhibited the growth of established tumors in NOG mice and reduced the EBV load in peripheral blood.. These results suggest that inhibition of mTOR signaling is a promising new strategy for improving treatment of EBV-associated T- and NK-cell lymphoma.

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Epstein-Barr Virus Infections; G1 Phase Cell Cycle Checkpoints; Herpesvirus 4, Human; Humans; Jurkat Cells; Killer Cells, Natural; Lymphoma, T-Cell; Mice; Sirolimus; T-Lymphocytes; TOR Serine-Threonine Kinases

Posttransplant lymphoproliferative disorder (PTLD) continues to be a devastating and potentially life-threatening complication in organ transplant recipients. PTLD is associated with EBV infection and can result in malignant B cell lymphomas. Here we demonstrate that the PI3K/Akt/mTOR pathway is highly activated in EBV+ B cell lymphoma lines derived from patients with PTLD. Treatment with the mTORC1 inhibitor Rapamycin (RAPA) partially inhibited the proliferation of EBV+ B cell lines. Resistance to RAPA treatment correlated with high levels of Akt phosphorylation. An mTORC1/2 inhibitor and a PI3K/mTOR dual inhibitor suppressed Akt phosphorylation and showed a greater anti-proliferative effect on EBV+ B lymphoma lines compared to RAPA. EBV+ B cell lymphoma lines expressed high levels of PI3Kδ. We demonstrate that PI3Kδ is responsible for Akt activation in EBV+ B cell lymphomas, and that selective inhibition of PI3Kδ by either siRNA, or a small molecule inhibitor, augmented the anti-proliferative effect of RAPA on EBV+ B cell lymphomas. These results suggest that PI3Kδ is a novel, potential therapeutic target for the treatment of EBV-associated PTLD and that combined blockade of PI3Kδ and mTOR provides increased efficacy in inhibiting proliferation of EBV+ B cell lymphomas.

Topics: Blotting, Western; Cell Line, Tumor; Cell Proliferation; Drug Synergism; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Humans; Imidazoles; Lymphoma, B-Cell; Lymphoproliferative Disorders; Mechanistic Target of Rapamycin Complex 1; Mechanistic Target of Rapamycin Complex 2; Multiprotein Complexes; Organ Transplantation; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Phosphorylation; Postoperative Complications; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Quinolines; Sirolimus; TOR Serine-Threonine Kinases

Epstein-Barr virus (EBV) infection and latency has been associated with malignancies, including nasopharyngeal carcinoma and Burkitt's lymphoma. EBV encoded latent membrane protein 2A (LMP2A) is expressed in most EBV-associated malignancies and as such provides a therapeutic target. Burkitt's lymphoma is a hematopoietic cancer associated with the translocation of c-MYC to one of the immunoglobulin gene promoters leading to abnormally high expression of MYC and development of lymphoma. Our laboratory has developed a murine model of EBV-associated Burkitt's lymphoma by crossing LMP2A transgenic mice with MYC transgenic mice. Since LMP2A has been shown to activate the PI3K/Akt/mTOR pathway, we tested the therapeutic efficacy of mTOR inhibitor rapamycin on the tumors and splenomegaly in these double transgenic mice (Tg6/λ-MYC). We found that rapamycin reversed splenomegaly in Tg6/λ-MYC mice prior to tumor formation by targeting B cells. In a tumor transfer model, we also found that rapamycin significantly decreased tumor growth, splenomegaly, and metastasis of tumor cells in the bone marrow of tumor recipients. Our data show that rapamycin may be a valuable candidate for the development of a treatment modality for EBV-positive lymphomas, such as Burkitt's lymphoma, and more importantly, provides a basis to develop inhibitors that specifically target viral gene function in tumor cells that depend on LMP2A signaling for survival and/or growth.

Topics: Animals; Apoptosis; Burkitt Lymphoma; Epstein-Barr Virus Infections; Female; Flow Cytometry; Herpesvirus 4, Human; Homeodomain Proteins; Male; Mice; Mice, 129 Strain; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; Proto-Oncogene Proteins c-myc; Sirolimus; Splenomegaly; Tumor Burden; Viral Matrix Proteins

Malignancies and opportunistic infections are frequently observed after solid-organ transplantation. Their occurrence strongly affects recipient survival. We report the case of a 29-year-old Tunisian kidney-recipient who was diagnosed simultaneously with post-transplant lymphoproliferative disease (PTLD) and visceral leishmaniasis (VL). Withdrawal of immunosuppressive therapy together with antiparasitic treatment using liposomal amphotericin B, and anti-CD20 antibodies medication resulted in cure of leishmaniasis and remission from PTLD. This case is of clinical interest because of the uncommon association of VL with PTLD after solid organ transplantation. It is also original by the favourable outcome of VL and PTLD, both known as life-threatening diseases. Also, it illustrates the predisposing role of immunosuppressive therapy in occurrence of opportunistic infections and malignancies after solid organ transplantation.

Topics: Adult; Amphotericin B; Antibodies, Monoclonal, Murine-Derived; Antiprotozoal Agents; Antiviral Agents; Epstein-Barr Virus Infections; Ganciclovir; Humans; Immunocompromised Host; Immunosuppressive Agents; Kidney Transplantation; Leishmaniasis, Visceral; Lymphoproliferative Disorders; Male; Meglumine; Meglumine Antimoniate; Opportunistic Infections; Organometallic Compounds; Postoperative Complications; Remission Induction; Rituximab; Sirolimus

Post-transplant lymphoproliferative disease (PTLD) can occur in different sites, such as lymph nodes, allograft, and central nervous system. We report a 6-year-old girl with end-stage renal disease secondary to hypoplastic-dysplastic kidneys, who received a kidney transplant. Thirty months post transplant, she developed PTLD in the tongue, an area of muscular tissue only. At that time her peripheral blood Epstein-Barr viral (EBV) load was only 40 copies/10(5) lymphocytes, though the tumor was EB early RNA (EBER) positive. Immunosuppression was reduced with initial improvement in her symptoms. One month later, she returned with abdominal complaints and a contained cecal abscess. The excised cecal tissue revealed CD20 and EBER-positive lymphoid cells. At the same time, her peripheral blood EBV copy number rose to 400 copies/10(5) lymphocytes. She was successfully treated for the progressive PTLD by complete cessation of immunosuppression and a modified reduced-dose chemotherapy protocol plus rituximab. Partial immunosuppression was eventually re-introduced with sirolimus and prednisone. She remains in remission 60 months post transplant, and 30 months post PTLD, with serum creatinine value maintained at 1.3 mg/dL. Unusual localization of PTLD to areas in non-lymphoid tissue without regional lymphoid involvement may result in misleading low peripheral blood EBV viral loads.

Topics: Abscess; Antibodies, Monoclonal; Antibodies, Monoclonal, Murine-Derived; Cecum; Child; Epstein-Barr Virus Infections; Female; Herpesvirus 4, Human; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Kidney Failure, Chronic; Kidney Transplantation; Lymphoproliferative Disorders; Postoperative Complications; Prednisone; Rituximab; Sirolimus; Tongue Neoplasms; Viral Load

IPEX syndrome (immune deficiency, polyendocrinopathy, enteropathy, X-linked) is a disorder or regulatory T cell (Treg) function which can result in early death due to infection or complications related to autoimmunity. Therapeutic options for these patients can include allogeneic stem cell transplantation (SCT) or the use of immunosuppressive regimens to control the manifestations of autoimmunity. We report a patient with IPEX syndrome who was managed with rapamycin and subsequently developed EBV induced lymphoma.

Topics: Child; Epstein-Barr Virus Infections; Genetic Diseases, X-Linked; Herpesvirus 4, Human; Humans; Immunologic Deficiency Syndromes; Immunosuppressive Agents; Infant; Lymphoma; Male; Polyendocrinopathies, Autoimmune; Protein-Losing Enteropathies; Sirolimus; Syndrome

Topics: Adult; Epstein-Barr Virus Infections; Humans; Immunosuppressive Agents; Kidney Transplantation; Lymphoma, Large B-Cell, Diffuse; Lymphoma, T-Cell; Lymphoproliferative Disorders; Male; Middle Aged; Protein Kinases; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

Natural killer (NK) lymphomas occurring more frequently in the Far East and South America respond poorly to anthracycline-based regimens. Here we report an in vivo NK lymphoma xenograft (NK-S1) derived from the testicular metastasis of a patient with an extranodal NK lymphoma (nasal type). The NK-S1 xenograft, established in severe combined immune deficient (SCID) mice retained the same imunophenotypic features as the original tumor. NK-S1 disseminated intra-abdominally to the testis, intestine and liver. Although doxorubicin, rapamycin, bevacizumab, rapamycin-doxorubicin, and bevacizumab-doxorubicin had no effects on the growth of subcutaneous NK-S1 xenografts, intraperitoneal (IP) delivery of cyclophosphamide caused complete tumor regression; this tumor regression was associated with apoptosis, upregulation of activated caspase-3, and cleaved Poly(ADP-ribose) polymerase (PARP). In an IP model of NK lymphoma, cyclophosphamide also prolonged the survival of mice and potently inhibited tumor dissemination and ascites formation. Our data suggest that the NK-S1 xenograft is a useful tool for screening preclinical drugs, and cyclophosphamide may be a useful drug for the treatment of this disease.

Topics: Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Bevacizumab; Blotting, Western; Caspase 3; Cyclophosphamide; Doxorubicin; Enzyme Activation; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Humans; Injections, Intraperitoneal; Killer Cells, Natural; Lymphoma, T-Cell, Peripheral; Male; Mice; Mice, SCID; Middle Aged; Neoplasm Transplantation; Poly(ADP-ribose) Polymerases; Sirolimus; Transplantation, Heterologous; Tumor Cells, Cultured

We report on a patient with relapsed chronic lymphocytic leukemia (CLL) treated with the novel mTOR inhibitor RAD001 within a phase II clinical trial. Although the patient initially responded to therapy, RAD001 was discontinued after 32 weeks due to progression and fludarabine-based chemotherapy was started. The patient subsequently developed a rapidly fatal Epstein-Barr-virus-associated lymphoproliferative disorder, clonally unrelated to the CLL. The clinical course suggests caution when using newer immunosuppressive drugs for treatment of CLL, especially in the context of additional purine analog therapy.

Topics: Aged; Epstein-Barr Virus Infections; Everolimus; Fatal Outcome; Female; Herpesvirus 4, Human; Humans; Immunosuppressive Agents; Leukemia, Lymphocytic, Chronic, B-Cell; Lymphoproliferative Disorders; Phosphoinositide-3 Kinase Inhibitors; Protein Kinases; Sirolimus; TOR Serine-Threonine Kinases; Vidarabine

Posttransplant lymphoproliferative disorder is a rare and often difficult diagnosis in patients with only cutaneous symptoms. A stepwise approach to diagnosis and classification can lead to successful treatment. We report a case of an EBV-associated posttransplant lymphoproliferative disorder (PTLD) occurring on the face with a primary cutaneous presentation. The appropriate diagnosis was made only after multiple biopsies and special stains. There was near complete resolution with decreased levels of iatrogenic immunosuppression. The diagnosis of Posttransplant lymphoproliferative disorder can be difficult to establish. A proper workup will aid in making an accelerated diagnosis and choosing appropriate treatment options.

Topics: Dose-Response Relationship, Drug; Epstein-Barr Virus Infections; Face; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Lung Transplantation; Lymphoproliferative Disorders; Male; Middle Aged; Mycophenolic Acid; Prednisone; Pulmonary Fibrosis; Sirolimus; Skin Diseases

Posttransplant lymphoproliferative disorders are a group of lymphoid proliferations and lymphomas that develop as a consequence of immunosuppression in recipients of solid organ or bone marrow allografts. We describe an unusual oral presentation of posttransplant Epstein-Barr virus-associated diffuse large B-cell lymphoma in a 45-year-old woman after pancreatic transplant.

Topics: Diagnosis, Differential; Epstein-Barr Virus Infections; Female; Herpesvirus 4, Human; Humans; Immunosuppressive Agents; Lymphoma, B-Cell; Lymphoma, Large B-Cell, Diffuse; Middle Aged; Mouth Neoplasms; Oral Ulcer; Pancreas Transplantation; RNA, Viral; Sirolimus; Tongue Diseases

Topics: Antibiotics, Antineoplastic; Epstein-Barr Virus Infections; Female; Graft Rejection; Herpesvirus 4, Human; Humans; Immunosuppressive Agents; Kidney Failure, Chronic; Kidney Transplantation; Liver Neoplasms; Middle Aged; Sirolimus; Smooth Muscle Tumor

EBV-infected B-cell lymphomas are a potentially life-threatening complication in bone marrow and solid organ transplant recipients. Immunosuppressive drugs required to prevent allograft rejection also impair anti-EBV T-cell immunity, thereby increasing the risk of EBV-associated disease. Here we demonstrate that the immunosuppressant rapamycin (RAPA) has a strong antiproliferative effect in vitro on B-cell lines derived from organ transplant recipients with EBV-associated posttransplant lymphoproliferative disorder (PTLD). Furthermore, RAPA significantly inhibits or delays the growth of solid tumors established from EBV-infected B-cell lines in a xenogeneic mouse model of PTLD. RAPA acts via cell cycle arrest, induction of apoptosis, and, most importantly, inhibition of interleukin 10 secretion, a necessary autocrine growth factor. The reduced interleukin 10 production is accompanied by corresponding decreases in the constitutive activation of the growth-promoting transcription factors signal transducer and activator of transcription 1 and 3. Thus, RAPA can limit B-cell lymphoma growth while simultaneously providing immunosuppression to prevent graft rejection in patients who are otherwise at risk for EBV-associated PTLD. Moreover, these findings may have application to other EBV-associated malignancies.

Topics: Animals; Antibiotics, Antineoplastic; Cell Division; DNA-Binding Proteins; Enzyme Activation; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Humans; Immunosuppressive Agents; Interleukin-10; Janus Kinase 1; Lymphoma, B-Cell; Male; Mice; Protein-Tyrosine Kinases; Signal Transduction; Sirolimus; STAT3 Transcription Factor; Trans-Activators; Transplantation; Xenograft Model Antitumor Assays

The role of sirolimus (SRL) as a rescue agent (n=42) and as a component of primary immunosuppression (n=8) was evaluated in a mixed population of 50 transplanted children receiving tacrolimus (liver: 26, heart: 5, intestinal: 5, liver-intestine: 9, lung: 1, bone marrow: 1, liver-kidney: 1, multivisceral: 1). Rescue indications for tacrolimus (TAC) failure were recurrent acute rejection and acute rejection complicating withdrawal of immunosuppression in posttransplant lymphoproliferative disorder (PTLD). Rescue indications for TAC toxicity were nephrotoxicity, pancreatitis, seizures, hypertrophic cardiomyopathy, and graft-versus-host disease.. Mean age at rescue was 11.5 years and mean follow-up was 204 (range 18-800) days. As primary immunosuppression, SRL+TAC prevented early acute rejection in 7/8 children. The indication for rescue resolved in 33/42 children. In children with TAC toxicity, this was associated with decrease in TAC doses by 50%, significant improvements in renal function, and continuing decline in Epstein-Barr virus (EBV) viral load in PTLD patients. Serious adverse events led to discontinuation of SRL in 9/42 rescue patients, 3 of them also experienced acute rejection. Three additional children also experienced acute rejection on SRL therapy (overall incidence 6/50, 12%). Pharmacokinetic analysis in the first week of SRL administration suggested a short half-life (11.8+/-5.5 hr, n=21).. SRL and reduced-dose TAC may achieve adequate immunosuppression without compromising renal function or enhancing EBV viremia significantly.

Topics: Acute Disease; Adolescent; Adult; Child; Child, Preschool; Epstein-Barr Virus Infections; Graft Rejection; Herpesvirus 4, Human; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Infant; Kidney; Lymphoproliferative Disorders; Recurrence; Sirolimus; Tacrolimus; Transplantation Immunology

Topics: Animals; Antineoplastic Agents; Clinical Trials, Phase II as Topic; Drug Evaluation, Preclinical; Epstein-Barr Virus Infections; Humans; Immunocompromised Host; Immunosuppressive Agents; Lymphoma, Non-Hodgkin; Mice; Neoplasm Metastasis; Postoperative Complications; Sirolimus; Transplantation Immunology; Tumor Virus Infections; Virus Activation