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Purpose of Review: The US Food and Drug Administration (FDA) approved two commercially available chimeric antigen receptor (CAR) T cell therapies for the treatment of relapsed B cell acute lymphoblastic leukemia (B-ALL) children and young adults less than 25 years of age and non-Hodgkin lymphoma in adults after promising results from early-phase single and multi-institutional clinical trials. In this review, we provide an overview of the practical aspects of a chimeric antigen T cell receptor (CAR-T) program development and the steps necessary for its successful implementation., Recent Findings: CAR-T therapy is a complex process and poses significant challenges as institutions prepare to deliver this therapy as a standard of care for the eligible patients. It requires a rigorous infrastructure with specific clinical, administrative, and regulatory demands. Institutions that led the clinical trials for CAR-T have adopted various approaches to integrate commercial CAR-T products into their program. Delivering commercial CAR-T cells outside the scope of clinical trials requires careful planning, allocation of resources, and utilization of existing infrastructure. Institutions may need to adapt the existing recommendations and guidelines and tailor them to meet the needs of their program and ensure appropriate financial reimbursement for this expensive but promising immunotherapy.

Axicabtagene ciloleucel (YESCARTA; Kite Pharma, a Gilead Company, Los Angeles CA) and tisagenlecleucel (KYMRIAH; Novartis Pharmaceuticals Corp., Basel, Switzerland) are two CD19-directed chimeric antigen receptor (CAR) T cell products currently approved by the US Food and Drug Administration; the European Medicines Agency; Health Canada; Ministry of Health, Labor and Welfare (Japan); and Therapeutic Goods Administration (Australia) for treatment of specific subtypes of relapsed/refractory aggressive B cell non-Hodgkin lymphoma (NHL). Although this approval has been transformative in the use of cellular immunotherapy in lymphoma, there are concerns regarding appropriate use of this novel therapy and of short- and long-term toxicities. To address these issues, representatives of the American Society of Transplantation and Cellular Therapy convened to recognize and address key issues surrounding the clinical application of CD19 CAR T cell therapy in B cell lymphomas, in collaboration with worldwide experts. The aim of this article is to provide consensus opinion from experts in the fields of hematopoietic cell transplantation, cellular immunotherapy, and lymphoma regarding key clinical questions pertinent to the use of CD19 CAR T cell products for the treatment of NHL. As the clinical practice using CAR T cells grows worldwide, we anticipate that this guidance will be relevant for hematology/oncology physicians who care for patients with lymphomas., (Copyright © 2019 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

On August 30, 2017, the U.S. Food and Drug Administration (US-FDA) approved tisagenlecleucel (KYMRIAH, Novartis, Basel, Switzerland), a synthetic bioimmune product of anti-CD19 chimeric antigen receptor-T cells (CAR-T), for the treatment of children and young adults with relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL). With this new era of personalized cancer immunotherapy, multiple challenges are present ranging from implementation of a CAR-T program to safe delivery of the drug, long-term toxicity monitoring and disease assessments. To address these issues, experts representing the American Society for Blood and Marrow Transplant (ASBMT), the European Group for Blood and Marrow Transplantation (EBMT), the International Society of Cell and Gene Therapy (ISCT), and the Foundation for the Accreditation of Cellular Therapy (FACT), formed a global CAR-T task force to identify and address key questions pertinent for hematologists and transplant physicians regarding the clinical use of anti CD19 CAR-T therapy in patients with B-ALL. This article presents an initial roadmap for navigating common clinical practice scenarios that will become more prevalent now that the first commercially available CAR-T product for B-ALL has been approved.

Although anti-retroviral therapy (ART) is successful in suppressing HIV-1 replication, HIV latently infected reservoirs are not eliminated, representing a major hurdle in efforts to eradicate the virus. Current strategies to eradicate HIV involve two steps: (1) the reactivation of latently infected cells with latency reversing agents (LRAs) to expose persisting HIV, and (2) the elimination of these cells with immune effectors while continuing ART to prevent reinfection. HIV-specific T cells (HSTs) can kill reactivated HIV-infected cells and are currently being evaluated in early-stage immunotherapy trials. HIV can mutate sequences in T cell epitopes and evade T cell-mediated killing of HIV-infected cells. However, by directing T cells to target multiple conserved, non-escaped HIV epitopes, the opportunity for viral escape can be reduced. Using a good manufacturing practice (GMP)-compliant platform, we manufactured HSTs against non-escape epitope targets (HST-NEETs) from HIV + and HIV-seronegative donors. HST-NEETs expanded to clinically relevant numbers, lysed autologous antigen-pulsed targets, and showed a polyfunctional pro-inflammatory cytokine response. Notably, HST-NEETs recognized multiple conserved, non-escaped HIV epitopes and their common variants. We propose that HST-NEETs could be used to eliminate reactivated virus from latently infected cells in HIV + individuals following LRA treatment. Additionally, HST-NEETs derived from HIV-negative individuals could be used post-transplant for HIV + individuals with hematologic malignancies to augment anti-viral immunity and destroy residual infected cells., (© 2019 The Author(s).)

Viral infections are a serious cause of morbidity and mortality following haematopoietic stem cell transplantation (HSCT). Adoptive cellular therapy with virus-specific T cells (VSTs) has been successful in preventing or treating targeted viruses in prior studies, but the composition of ex vivo expanded VST and the critical cell populations that mediate antiviral activity in vivo are not well defined. We utilized deep sequencing of the T-cell receptor beta chain (TCRB) in order to classify and track VST populations in 12 patients who received VSTs following HSCT to prevent or treat viral infections. TCRB sequencing was performed on sorted VST products and patient peripheral blood mononuclear cells samples. TCRB diversity was gauged using the Shannon entropy index, and repertoire similarity determined using the Morisita-Horn index. Similarity indices reflected an early change in TCRB diversity in eight patients, and TCRB clonotypes corresponding to targeted viral epitopes expanded in eight patients. TCRB repertoire diversity increased in nine patients, and correlated with cytomegalovirus (CMV) viral load following VST infusion (P = 0·0071). These findings demonstrate that allogeneic VSTs can be tracked via TCRB sequencing, and suggests that T-cell receptor repertoire diversity may be critical for the control of CMV reactivation after HSCT., (© 2019 British Society for Haematology and John Wiley & Sons Ltd.)

Background: Medulloblastoma (MB), the most common pediatric brain cancer, presents with a poor prognosis in a subset of patients with high risk disease, or at recurrence, where current therapies are ineffective. Cord blood (CB) natural killer (NK) cells may be promising off-the-shelf effector cells for immunotherapy due to their recognition of malignant cells without the need for a known target, ready availability from multiple banks, and their potential to expand exponentially. However, they are currently limited by immune suppressive cytokines secreted in the MB tumor microenvironment including Transforming Growth Factor β (TGF-β). Here, we address this challenge in in vitro models of MB., Methods: CB-derived NK cells were modified to express a dominant negative TGF-β receptor II (DNRII) using retroviral transduction. The ability of transduced CB cells to maintain function in the presence of medulloblastoma-conditioned media was then assessed., Results: We observed that the cytotoxic ability of nontransduced CB-NK cells was reduced in the presence of TGF-β-rich, medulloblastoma-conditioned media (21.21 ± 1.19% killing at E:T 5:1 in the absence vs. 14.98 ± 2.11% in the presence of medulloblastoma-conditioned media, n = 8, p = 0.02), but was unaffected in CB-derived DNRII-transduced NK cells (21.11 ± 1.84% killing at E:T 5:1 in the absence vs. 21.81 ± 3.37 in the presence of medulloblastoma-conditioned media, n = 8, p = 0.85. We also observed decreased expression of CCR2 in untransduced NK cells (mean CCR2 MFI 826 ± 117 in untransduced NK + MB supernatant from mean CCR2 MFI 1639.29 ± 215 in no MB supernatant, n = 7, p = 0.0156), but not in the transduced cells. Finally, we observed that CB-derived DNRII-transduced NK cells may protect surrounding immune cells by providing a cytokine sink for TGF-β (decreased TGF-β levels of 610 ± 265 pg/mL in CB-derived DNRII-transduced NK cells vs. 1817 ± 342 pg/mL in untransduced cells; p = 0.008)., Conclusions: CB NK cells expressing a TGF-β DNRII may have a functional advantage over unmodified NK cells in the presence of TGF-β-rich MB, warranting further investigation on its potential applications for patients with medulloblastoma.

Purpose: Tumor-associated antigen cytotoxic T cells (TAA-Ts) represent a new, potentially effective and nontoxic therapeutic approach for patients with relapsed or refractory solid tumors. In this first-in-human trial, we investigated the safety of administering TAA-Ts that target Wilms tumor gene 1, preferentially expressed antigen of melanoma, and survivin to patients with relapsed/refractory solid tumors., Materials and Methods: TAA-T products were generated from autologous peripheral blood and infused over three dose levels: 1, 2, and 4 × 10 7 cells/m 2 . Patients were eligible for up to eight infusions administered 4 to 7 weeks apart. We assessed dose limiting toxicity during the first 45 days after infusion. Disease response was determined within the context of a phase I trial., Results: There were no dose-limiting toxicities. Of 15 evaluable patients, 11 (73%) with stable disease or better at day 45 postinfusion were defined as responders. Six responders remain without progression at a median of 13.9 months (range, 4.1 to 19.9 months) after initial TAA-Ts. Patients who were treated at the highest dose level showed the best clinical outcomes, with a 6-month progression-free survival of 73% after TAA-T infusion compared with a 38% 6-month progression-free survival with prior therapy. Antigen spreading and a reduction in circulating tumor-associated antigens using digital droplet polymerase chain reaction was observed in patients after TAA-T infusion., Conclusion: TAA-Ts safely induced disease stabilization, prolonged time to progression, and were associated with antigen spreading and a reduction in circulating tumor-associated antigen DNA levels in patients with relapsed/refractory solid tumors without lymphodepleting chemotherapy before infusion. TAA-Ts are a promising new treatment approach for patients with solid tumors.

T-cell lymphomas represent a subpopulation of non-Hodgkin lymphomas with poor outcomes when treated with conventional chemotherapy. A variety of novel agents have been introduced as new treatment strategies either as first-line treatment or in conjunction with chemotherapy. Immunotherapy has been demonstrated to be a promising area for new therapeutics, including monoclonal antibodies and adoptive cellular therapeutics. T-cell therapeutics have been shown to have significant success in the treatment of B-cell malignancies and are rapidly expanding as potential treatment options for other cancers including T-cell lymphomas. Although treating T-cell lymphomas with T-cell therapeutics has unique challenges, multiple targets are currently being studied both preclinically and in clinical trials., (Copyright © 2019 International Society for Cell and Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Background: Despite advances in immunotherapeutic strategies for neuroblastoma (NBL), relapse remains a significant cause of mortality for high risk patients. The discovery of novel tumor associated antigens to improve efficacy and minimize the toxicities of immunotherapy is therefore warranted. R eceptor Tyrosine Kinase-like O rphan R eceptor-1 and 2 (ROR1 and ROR2) have been found to be expressed in several malignancies with limited expression in healthy tissues. Objectives: Given their role in tumor migration and proliferation and the fact that they were originally cloned from a NBL cell line, we hypothesized that ROR1 and ROR2 could serve as potential targets for anti-ROR1 and anti-ROR2 based immunotherapies in NBL. Methods: We characterized the mRNA and protein expression of ROR1 and ROR2 in NBL cell lines and tissue microarrays of patient samples. To explore the potential of ROR1 targeting, we performed in vitro cytotoxicity assays against NBL using NK92 cells as effector cells. Results: Both ROR1 and ROR2 are expressed across all stages of NBL. In patients with non-MYC amplified tumors, expression of ROR1/ROR2 correlated with survival and prognosis. Moreover, in a proof-of-concept experiment, pretreatment of NBL cell line with anti-ROR1 antibody showed additive cytotoxicity with NK92 cells. Conclusions: ROR1 and ROR2 could serve as novel targets for immunotherapy in NBL. The additive effect of anti-ROR1 antibodies with NK cells needs to be explored further to evaluate the possibility of combining anti-ROR1 antibodies with immune effectors such as NK92 cells as a potential off-the shelf immunotherapy for NBL and other ROR1 expressing malignancies.

Background: Zika virus (ZIKV) infection can cause severe birth defects in newborns with no effective currently available treatment. Adoptive transfer of virus-specific T cells has proven to be safe and effective for the prevention or treatment of many viral infections, and could represent a novel treatment approach for patients with ZIKV infection. However, extending this strategy to the ZIKV setting has been hampered by limited data on immunogenic T-cell antigens within ZIKV. Hence, we have generated ZIKV-specific T cells and characterized the cellular immune responses against ZIKV antigens., Methods: T-cell products were generated from peripheral blood of ZIKV-exposed donors, ZIKV-naive adult donors and umbilical cord blood by stimulation with pentadecamer (15mer) overlapping peptide libraries spanning four ZIKV polyproteins (C, M, E and NS1) using a Good Manufacturing Practice-compliant protocol., Results: We successfully generated T cells targeting ZIKV antigens with clinically relevant numbers. The ex vivo-expanded T cells comprised both CD4 + and CD8 + T cells that were able to produce Th1-polarized effector cytokines and kill ZIKV-infected HLA-matched monocytes, confirming functionality of this unique T-cell product as a potential "off-the-shelf" therapeutic. Epitope mapping using peptide arrays identified several novel HLA class I and class II-restricted epitopes within NS1 antigen, which is essential for viral replication and immune evasion., Discussion: Our findings demonstrate that it is feasible to generate potent ZIKV-specific T cells from a variety of cell sources including virus naïve donors for future clinical use in an "off-the-shelf" setting., (Copyright © 2019 International Society for Cell and Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Adoptive transfer of virus-specific T cells (VSTs) has been shown to be safe and effective in stem cell transplant recipients. However, the lack of virus-experienced T cells in donor cord blood (CB) has prevented the development of ex vivo expanded donor-derived VSTs for recipients of this stem cell source. Here we evaluated the feasibility and safety of ex vivo expansion of CB T cells from the 20% fraction of the CB unit in pediatric patients receiving a single CB transplant (CBT). In 2 clinical trials conducted at 2 separate sites, we manufactured CB-derived multivirus-specific T cells (CB-VSTs) targeting Epstein-Barr virus (EBV), adenovirus, and cytomegalovirus (CMV) for 18 (86%) of 21 patients demonstrating feasibility. Manufacturing for 2 CB-VSTs failed to meet lot release because of insufficient cell recovery, and there was 1 sterility breach during separation of the frozen 20% fraction. Delayed engraftment was not observed in patients who received the remaining 80% fraction for the primary CBT. There was no grade 3 to 4 acute graft-versus-host disease (GVHD) associated with the infusion of CB-VSTs. None of the 7 patients who received CB-VSTs as prophylaxis developed end-organ disease from CMV, EBV, or adenovirus. In 7 patients receiving CB-VSTs for viral reactivation or infection, only 1 patient developed end-organ viral disease, which was in an immune privileged site (CMV retinitis) and occurred after steroid therapy for GVHD. Finally, we demonstrated the long-term persistence of adoptively transferred CB-VSTs using T-cell receptor-Vβ clonotype tracking, suggesting that CB-VSTs are a feasible addition to antiviral pharmacotherapy., (© 2019 by The American Society of Hematology.)

Purpose: The ability of natural killer (NK) cells to lyse allogeneic targets, without the need for explicit matching or priming, makes them an attractive platform for cell-based immunotherapy. Umbilical cord blood is a practical source for generating banks of such third-party NK cells for "off-the-shelf" cell therapy applications. NK cells are highly cytolytic, and their potent antitumor effects can be rapidly triggered by a lack of HLA expression on interacting target cells, as is the case for a majority of solid tumors, including neuroblastoma. Neuroblastoma is a leading cause of pediatric cancer-related deaths and an ideal candidate for NK-cell therapy. However, the antitumor efficacy of NK cells is limited by immunosuppressive cytokines in the tumor microenvironment, such as TGFβ, which impair NK cell function and survival., Experimental Design: To overcome this, we genetically modified NK cells to express variant TGFβ receptors, which couple a mutant TGFβ dominant-negative receptor to NK-specific activating domains. We hypothesized that with these engineered receptors, inhibitory TGFβ signals are effectively converted to activating signals., Results: Modified NK cells exhibited higher cytotoxic activity against neuroblastoma in a TGFβ-rich environment in vitro and superior progression-free survival in vivo , as compared with their unmodified controls., Conclusions: Our results support the development of "off-the-shelf" gene-modified NK cells, that overcome TGFβ-mediated immune evasion, in patients with neuroblastoma and other TGFβ-secreting malignancies., (©2019 American Association for Cancer Research.)

Background: Sickle cell disease (SCD) is increasingly recognized as a red blood cell disorder modulated by abnormally increased inflammation. We have previously shown that in patients with SCD not on a disease-modifying therapy (hydroxyurea or chronic transfusions), natural killer (NK) cell numbers are increased. In the current study, we further investigated the NK cell function to determine if there was evidence of increased activation and cytotoxicity., Procedure: We conducted a cross-sectional study of 44 patients with HbSS/HbSβ 0 thalassemia at steady state (hydroxyurea = 13, chronic transfusion = 11, no disease-modifying therapy = 20) and 23 healthy controls. Using a fresh blood sample, NK immunophenotyping was performed as follows: NK cells (CD3 - CD56 + lymphocytes) were evaluated for makers associated with activation (NKG2D, NKp30, NKp44, and CD69) and maturity (CD57, killer immunoglobulin-like receptors (KIR), and CD56dim). Degranulation and cytotoxicity assays were performed to evaluate NK cell function., Results: Patients with SCD who were not on disease-modifying therapy had a higher number of NK cells with an immunophenotype associated with increased cytotoxicity (NKG2D + , NKp30 + , CD56dim + , and KIR + NK cells) compared with healthy controls and patients on hydroxyurea. NK cells from SCD patients not on disease-modifying therapy demonstrated significantly increased cytotoxicity (measured by assaying NK cell killing of the K562 cell line) compared with healthy controls (P = 0.005). Notably, NK cell cytotoxicity against K562 cells in the hydroxyurea or chronic transfusion patients was not significantly different from that in healthy controls., Conclusion: SCD is associated with increased NK cell function as well as increased NK cell numbers, which appears to be normalized with disease-modifying therapy., (© 2019 Wiley Periodicals, Inc.)

Mycobacterial Infections can be severe in patients with T-cell deficiency or phagocyte disorders, and treatment is frequently complicated by antimicrobial resistance. Restoration of T-cell immunity via stem cell transplantation facilitates control of mycobacterial infections, but presence of active infections during transplantation is associated with a higher risk of mortality. Adoptive T cell immunotherapy has been successful in targeting viruses, but has not been attempted to treat mycobacterial infections. We sought to expand and characterize mycobacterial-specific T-cells derived from healthy donors in order to determine suitability for adoptive immunotherapy. Mycobacteria-specific T-cells (MSTs) were generated from 10 healthy donors using a rapid ex vivo expansion protocol targeting five known mycobacterial target proteins (AG85B, PPE68, ESXA, ESXB, and ADK). MSTs were compared to T-cells expanded from the same donors using lysate from M. tuberculosis or purified protein derivative from M. avium (sensitin). MST expansion from seven patients with primary immunodeficiency disorders (PID) and two patients with IFN-γ autoantibodies and invasive M. avium infections. MSTs expanded from healthy donors recognized a median of 3 of 5 antigens, with production of IFN-γ, TNF, and GM-CSF in CD4 + T cells. Comparison of donors who received BCG vaccine ( n = 6) to those who did not ( n = 4) showed differential responses to PPE68 ( p = 0.028) and ADK ( p = 0.015) by IFN-γ ELISpot. MSTs expanded from lysate or sensitin also recognized multiple mycobacterial antigens, with a statistically significant differences noted only in the response to PPE68 ( p = 0.016). MSTs expanded from patients with primary immunodeficiency (PID) and invasive mycobacterial infections showed activity against mycobacterial antigens in only two of seven subjects, whereas both patients with IFN-γ autoantibodies recognized mycobacterial antigens. Thus, MSTs can be generated from donors using a rapid expansion protocol regardless of history of BCG immunization. Most tested PID patients had no detectable T-cell immunity to mycobacteria despite history of infection. MSTs may have clinical utility for adoptive immunotherapy in T-cell deficient patients with invasive mycobacterial infections.

We report the generation of magnetically responsive, cord blood-derived natural killer (NK) cells using iron oxide nanoparticles (IONPs). NK cells are a promising immune cell population for cancer cell therapy as they can target and lyse target tumor cells without prior education. However, NK cells cannot home to disease sites based on antigen recognition, instead relying primarily on external stimuli and chemotactic gradients for transport. Hence, we hypothesized that conjugating IONPs onto the surface of NK cells provides an added feature of magnetic homing to the NK cells, improving their therapeutic function. We describe a robust design for conjugating the IONPs onto the surface of NK cells, which maintains their intrinsic phenotype and function. The conferred magnetic-responsiveness is utilized to improve the cytolytic function of the NK cells for target cells in 2D and 3D models. These findings demonstrate the feasibility of improving NK cell homing and therapeutic efficacy with our NK:IONP "biohybrid".

Paediatric Strategy Forums have been created by the multistakeholder organisation, ACCELERATE, and the European Medicines Agency to facilitate dialogue between all relevant stakeholders and suggest strategies in critical areas of paediatric oncology drug development. As there are many medicines being developed for B-cell malignancies in adults but comparatively few in children with these malignancies, a Paediatric Strategy Forum was held to discuss the best approach to develop these products for children. It was concluded that as current frontline therapy is highly successful, despite associated acute toxicity, de-escalation of this or substitution of presently used drugs with new medicines can only be undertaken when there is an effective salvage regimen, which is currently not available. Therefore priority should be given to developing treatment for patients with relapsed and refractory mature B-cell lymphomas. The consensus of the clinicians attending the meeting was that CAR T-cells, T-cell engagers and antibody drug conjugates (excluding those with a vinca alkaloid-like drug) presently have the greatest probability of providing benefit in relapse in view of their mechanism of action. However, as producing autologous CAR T-cells currently takes at least 4 weeks, they are not products which could be quickly employed initially at relapse in rapidly progressing mature B-cell malignancies but only for the consolidation phase of the treatment. Global, industry-supported, academic-sponsored studies testing compounds from different pharmaceutical companies simultaneously should be considered in rare populations, and it was proposed that an international working group be formed to develop an overarching clinical trials strategy for these disease groups. Future Forums are planned for other relevant paediatric oncologic diseases with a high unmet medical need and relevant molecular targets., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

On August 30, 2017 the US Food and Drug Administration approved tisagenlecleucel (Kymriah; Novartis, Basel, Switzerland), a synthetic bioimmune product of anti-CD19 chimeric antigen receptor T cells (CAR-T), for the treatment of children and young adults with relapsed/refractory B cell acute lymphoblastic leukemia (B-ALL). With this new era of personalized cancer immunotherapy, multiple challenges are present, ranging from implementation of a CAR-T program to safe delivery of the drug, long-term toxicity monitoring, and disease assessments. To address these issues experts representing the American Society for Blood and Marrow Transplant, the European Society for Blood and Marrow Transplantation, the International Society of Cell and Gene Therapy, and the Foundation for the Accreditation of Cellular Therapy formed a global CAR-T task force to identify and address key questions pertinent for hematologists and transplant physicians regarding the clinical use of anti CD19 CAR-T therapy in patients with B-ALL. This article presents an initial roadmap for navigating common clinical practice scenarios that will become more prevalent now that the first commercially available CAR-T product for B-ALL has been approved., (Copyright © 2018 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.)

Viral infections are common and can be potentially fatal in patients with primary immunodeficiency disorders (PIDDs). Because viral susceptibility stems from poor to absent T-cell function in most patients with moderate to severe forms of PIDD, adoptive immunotherapy with virus-specific T cells (VSTs) has been used to combat viral infections in the setting of hematopoietic stem cell transplantation in multiple clinical trials. Most trials to date have targeted cytomegalovirus, EBV, and adenovirus either alone or in combination, although newer trials have expanded the number of targeted pathogens. Use of banked VSTs produced from third-party donors has also been studied as a method of expanding access to this therapy. Here we review the clinical experience with VST therapy for patients with PIDDs as well as future potential targets and approaches for the use of VSTs to improve clinical outcomes for this specific patient population., (Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

In 2017, an autologous chimeric antigen receptor (CAR) T cell therapy indicated for children and young adults with relapsed and/or refractory CD19 + acute lymphoblastic leukaemia became the first gene therapy to be approved in the USA. This innovative form of cellular immunotherapy has been associated with remarkable response rates but is also associated with unique and often severe toxicities, which can lead to rapid cardiorespiratory and/or neurological deterioration. Multidisciplinary medical vigilance and the requisite health-care infrastructure are imperative to ensuring optimal patient outcomes, especially as these therapies transition from research protocols to standard care. Herein, authors representing the Pediatric Acute Lung Injury and Sepsis Investigators (PALISI) Network Hematopoietic Stem Cell Transplantation (HSCT) Subgroup and the MD Anderson Cancer Center CAR T Cell Therapy-Associated Toxicity (CARTOX) Program have collaborated to provide comprehensive consensus guidelines on the care of children receiving CAR T cell therapy.

Autologous T cells targeting Epstein-Barr virus (EBV) latent membrane proteins (LMPs) have shown safety and efficacy in the treatment of patients with type 2 latency EBV-associated lymphomas for whom standard therapies have failed, including high-dose chemotherapy followed by autologous stem-cell rescue. However, the safety and efficacy of allogeneic donor-derived LMP-specific T cells (LMP-Ts) have not been established for patients who have undergone allogeneic hematopoietic stem-cell transplantation (HSCT). Therefore, we evaluated the safety and efficacy of donor-derived LMP-Ts in 26 patients who had undergone allogeneic HSCT for EBV-associated natural killer/T-cell or B-cell lymphomas. Seven patients received LMP-Ts as therapy for active disease, and 19 were treated with adjuvant therapy for high-risk disease. There were no immediate infusion-related toxicities, and only 1 dose-limiting toxicity potentially related to T-cell infusion was seen. The 2-year overall survival (OS) was 68%. Additionally, patients who received T-cell therapy while in complete remission after allogeneic HSCT had a 78% OS at 2 years. Patients treated for B-cell disease (n = 10) had a 2-year OS of 80%. Patients with T-cell disease had a 2-year OS of 60%, which suggests an improvement compared with published posttransplantation 2-year OS rates of 30% to 50%. Hence, this study shows that donor-derived LMP-Ts are a safe and effective therapy to prevent relapse after transplantation in patients with B cell- or T cell-derived EBV-associated lymphoma or lymphoproliferative disorder and supports the infusion of LMP-Ts as adjuvant therapy to improve outcomes in the posttransplantation setting. These trials were registered at www.clinicaltrials.gov as #NCT00062868 and #NCT01956084., (© 2018 by The American Society of Hematology.)

Acute exercise preferentially mobilizes cytotoxic T-cells, NK-cells and non-classical monocytes to the bloodstream under the influence of hemodynamic forces and/or β 2 -adrenergic receptor (β 2 -AR) signaling. However, the relative contribution of these mechanisms to the redeployment of the most exercise-responsive cell types is largely unknown. We determined the lymphocyte and monocyte subtypes mobilized to blood during exercise via β 2 -AR signaling whilst controlling for β 1 -AR mediated reductions in hemodynamic forces. In a randomized, double blind, complete cross-over design, 14 healthy cyclists exercised for 30-minutes at +10% of blood lactate threshold after ingesting: (1) a placebo, (2) a β 1 -preferential antagonist (10 mg bisoprolol), or (2) a non-preferential β 1  + β 2 -antagonist (80 mg nadolol) across three trials separated by >7-days. Bisoprolol was administered to reduce hemodynamic forces (heart rate and blood pressure) during exercise to levels comparable with nadolol but without blocking β 2 -ARs. The mobilization of total NK-cells, terminally differentiated (CD57+) NK-cells, central memory, effector memory and CD45RA+ effector memory CD8+ T-cells; non-classical monocytes; and γδ T-cells were significantly blunted or abrogated under nadolol compared to both bisoprolol and placebo, indicating that the exercise-induced mobilization of these cell types to the blood is largely influenced by β 2 -AR signaling. Nadolol failed to inhibit the mobilization of classical monocytes, CD4+ T-cells (and their subsets) or naïve CD8+ T-cells, indicating that these cell types are mobilized with exercise independently of the β 2 -AR. We conclude that the preferential mobilization of NK-cells, non-classical monocytes and differentiated subsets of CD8+ T-cells with exercise is largely dependent on catecholamine signaling through the β 2 -AR. These findings provide mechanistic insights by which distinct lymphocyte and monocyte subtypes are preferentially mobilized to protect the host from anticipated injury or infection in response to an acute stress response., (Copyright © 2018. Published by Elsevier Inc.)

Adoptive T cell therapy has had dramatic successes in the treatment of virus-related malignancies and infections following hematopoietic stem cell transplantation. We adapted this method to produce ex vivo expanded HIV-specific T cells (HXTCs), with the long-term goal of using HXTCs as part of strategies to clear persistent HIV infection. In this phase 1 proof-of-concept study (NCT02208167), we administered HXTCs to antiretroviral therapy (ART)-suppressed, HIV-infected participants. Participants received two infusions of 2 × 10 7 cells/m 2 HXTCs at a 2-week interval. Leukapheresis was performed at baseline and 12 weeks post-infusion to measure the frequency of resting cell infection by the quantitative viral outgrowth assay (QVOA). Overall, participants tolerated HXTCs, with only grade 1 adverse events (AEs) related to HXTCs. Two of six participants exhibited a detectable increase in CD8 T cell-mediated antiviral activity following the two infusions in some, but not all, assays. As expected, however, in the absence of a latency reversing agent, no meaningful decline in the frequency of resting CD4 T cell infection was detected. HXTC therapy in ART-suppressed, HIV-infected individuals appears safe and well tolerated, without any clinical signs of immune activation, likely due to the low residual HIV antigen burden present during ART., (Copyright © 2018. Published by Elsevier Inc.)

Adoptive transfer of virus-specific T-cells (VSTs) effectively treats viral infections following allogeneic hematopoietic stem cell transplantation (alloHSCT), but logistical difficulties have limited widespread availability of VSTs as a post-transplant therapeutic. A single exercise bout mobilizes VSTs specific for latent herpesviruses (i.e. CMV and EBV) to peripheral blood and augments their ex vivo expansion. We investigated whether exercise exerts similar effects on T-cells specific for a NON-latent virus such as adenovirus, which is a major contributor to infection-related morbidity and mortality after alloHSCT. Thirty minutes of cycling exercise increased circulating adenovirus-specific T-cells 2.0-fold and augmented their ex vivo expansion by ~33% compared to rest without altering antigen and MHC-specific autologous target cell killing capabilities. We conclude that exercise is a simple and economical adjuvant to boost the isolation and manufacture of therapeutic VSTs specific to latent and non-latent viruses from healthy donors., (Copyright © 2018. Published by Elsevier Inc.)

Allogeneic hematopoietic cell transplantation (HCT) with myeloablative conditioning for disorders associated with excessive inflammation such as hemophagocytic lymphohistiocytosis (HLH) is associated with early mortality. A multicenter prospective phase 2 trial of reduced-intensity conditioning with melphalan, fludarabine, and intermediate-timing alemtuzumab was conducted for HLA matched or single HLA locus mismatched related or unrelated donor HCT in a largely pediatric cohort. Graft-versus-host disease (GVHD) prophylaxis was cyclosporine with methylprednisolone. The primary end point was 1-year overall survival (OS). Thirty-four patients with HLH and 12 with other primary immune deficiencies were transplanted. With a median follow-up of 20 months, the 1-year OS for transplanted patients was 80.4% (90% confidence interval [CI], 68.6%-88.2%). Five additional deaths by 16 months yielded an 18-month OS probability of 66.7% (90% CI, 52.9%-77.3%). Two patients experienced primary graft failure, and 18 patients either experienced a secondary graft failure or required a second intervention (mostly donor lymphocyte infusion [DLI]). At 1 year, the proportion of patients alive with sustained engraftment without DLI or second HCT was 39.1% (95% CI, 25.2%-54.6%), and that of being alive and engrafted (with or without DLI) was 60.9% (95% CI, 45.4 %-74.9%). The day 100 incidence of grade II to IV acute GVHD was 17.4% (95% CI, 8.1%-29.7%), and 1-year incidence of chronic GVHD was 26.7% (95% CI, 14.6%-40.4%). Although the trial demonstrated low early mortality, the majority of surviving patients required DLI or second HCT. These results demonstrate a need for future approaches that maintain low early mortality with improved sustained engraftment. The trial was registered at Clinical Trials.gov (NCT 01998633)., (© 2018 by The American Society of Hematology.)

Viral infections can be life threatening in patients with severe combined immunodeficiency (SCID) and other forms of profound primary immunodeficiency disorders both before and after hematopoietic stem cell transplantation (HSCT). Adoptive immunotherapy with virus-specific T cells (VSTs) has been utilized in many patients in the setting of HSCT, but has very rarely been attempted for treatment of viral infections before HSCT. Here we describe the use of VSTs in an infant with RAG1 SCID who had developed disseminated adenovirus which failed to improve on cidofovir. Adenovirus cleared following 2 doses of VSTs and marrow infusion from a matched unrelated donor, without incidence of graft versus host disease. T cell receptor-b sequencing demonstrated expansion of adenovirus-specific T cell fraction of the VSTs, suggesting that infusion facilitated viral clearance. This report suggests that VSTs are likely safe in the pre-HSCT period, and may be a useful bridge therapy for infants with SCID and persistent viral infections., (Copyright © 2018 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.)

T-cell chronic active Epstein-Barr virus (CAEBV) is a rare disease in which EBV is present predominantly in T cells that infiltrate the tissues; patients have high levels of EBV in the blood. If untreated, patients often develop liver failure, hemophagocytic lymphohistiocytosis, coronary artery aneurysms, EBV infiltrating T cells impairing organ function, or T-cell lymphomas refractory to treatment. At present, hematopoietic stem-cell transplantation is the only curative therapy, and it is critical to make a proper diagnosis and initiate transplantation before the disease progresses to an irreversible stage. Specific medications such as high-dose systemic corticosteroids or ganciclovir combined with either histone deacetylase inhibitors or bortezomib may temporarily reduce systemic toxicity associated with T-cell CAEBV and allow the patient time to receive a transplant. Relapses of the disease after transplantation have also occurred, and the use of donor-derived virus-specific T cells may help to treat these relapses., (© 2018 by The American Society of Hematology.)

Immune therapies are fast becoming paradigm-changing treatment options for patients with hematologic cancers. The field has grown exponentially as it expands to nonmalignant blood diseases. This Perspective article introduces the review series describing some of the latest advances in this field and highlighting some of the current obstacles and new opportunities for the future. Specifically, the series provides in-depth discussion on a selection of emerging immunotherapies now available to patients for hematologic diseases, including cancer vaccines, chimeric antigen receptor T cells, and immunotherapies to regulate inflammation in nonmalignant blood disorders., (© 2018 by The American Society of Hematology.)

The Berlin Patient represents the first and only functional HIV cure achieved by hematopoietic stem cell transplant (HSCT). In subsequent efforts to replicate this result, HIV rebounded post-HSCT after withdrawal of antiretroviral therapy. Providing HIV-specific immunity through adoptive T cell therapy may prevent HIV rebound post-HSCT by eliminating newly infected cells before they can seed systemic infection. Adoptive T cell therapy has demonstrated success in boosting Epstein-Barr virus and cytomegalovirus-specific immunity post-HSCT, controlling viral reactivation. However, T cell immunotherapies to boost HIV-specific immunity have been limited by single-epitope specificity and minimal persistence or efficacy in vivo. To improve this strategy, we sought to generate allogeneic HIV-specific T cells from human leukocyte antigen (HLA)-A02+ HIV-negative adult or cord blood donors. We focused on HLA-A02+ donors due to well-characterized epitope restrictions observed in HIV+ populations. We show that multi-antigen HIV-specific T cells can be generated from naive T cells of both cord blood and adults using a reproducible good manufacturing practice (GMP)-grade protocol. This product lysed antigen-pulsed targets and suppressed active HIV in vitro. Interestingly, these cells displayed broad epitope recognition despite lacking recognition of the common HLA-A02-restricted HIV epitope Gag SL9. This first demonstration of functional multi-antigen HIV-specific T cells has implications for improving treatment of HIV through allogeneic HSCT., (Copyright © 2018. Published by Elsevier Inc.)

Immune-based treatment strategies, such as checkpoint inhibition and chimeric antigen receptor (CAR) T cells, have started a new frontier for treatment in non-Hodgkin lymphoma (NHL). Checkpoint inhibition has been most successful in Hodgkin lymphoma, where higher expression of PD-L1 is correlated with better overall response rate. Combinations of checkpoint inhibition with various chemotherapy or biologics are in clinical trials, with initially promising results and manageable safety profiles. CAR T-cell therapies that target CD19 are a promising and attractive therapy for B-cell NHLs, with a product approved by the US Food and Drug Administration in 2017. Changes in the target, hinge, or costimulatory domain can dramatically alter the persistence and efficacy of the CAR T cells. The ZUMA trials from Kite used CD19-(CD28z) CAR T cells, whereas the TRANSCEND studies from Juno and the JULIET studies from Novartis used CD19-(4-1BBz) CARs. Despite the recent successes with CAR T-cell clinical trials, major concerns associated with this therapy include cytokine release syndrome, potential neurotoxicities, B-cell aplasia, loss of tumor antigen leading to relapse, and cost and accessibility of the treatment. Although first-generation CAR T-cell therapies have failed in solid malignancies, newer second- and third-generation CAR T cells that target antigens other than CD19 (such as mesothelin or B-cell maturation antigen) are being studied in clinical trials for treatment of lung cancer or multiple myeloma. Overall, immune-based treatment strategies have given oncologists and patients hope when there used to be none, as well as a new basket of tools yet to come with further research and development.

Cell therapy currently performs an important role in the treatment of patients with various hematological malignancies. The response to the cell therapy is regulated by multiple factors including the patient's immune system status, genetic profile, stage at diagnosis, age, and underlying disease. Cell therapy that does not require genetic manipulation can be mediated by donor lymphocyte infusion strategies, selective depletion in the post-transplant setting and the ex vivo expansion of antigen-specific T cells. For hematologic malignancies, cell therapy is contributing to enhanced clinical responses and overall survival and the immune response to cell therapy is predictive of response in multiple cancer types. In this review we summarize the available T cell therapeutics that do not rely on gene engineering for the treatment of patients with blood cancers., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Purpose Transforming growth factor-β (TGF-β) production in the tumor microenvironment is a potent and ubiquitous tumor immune evasion mechanism that inhibits the expansion and function of tumor-directed responses; therefore, we conducted a clinical study to discover the effects of the forced expression of a dominant-negative TGF-β receptor type 2 (DNRII) on the safety, survival, and activity of infused tumor-directed T cells. Materials and Methods In a dose escalation study, eight patients with Epstein Barr virus-positive Hodgkin lymphoma received two to 12 doses of between 2 × 10 7 and 1.5 × 10 8 cells/m 2 of DNRII-expressing T cells with specificity for the Epstein Barr virus-derived tumor antigens, latent membrane protein (LMP)-1 and LMP-2 (DNRII-LSTs). Lymphodepleting chemotherapy was not used before infusion. Results DNRII-LSTs were resistant to otherwise inhibitory concentrations of TGF-β in vitro and retained their tumor antigen-specific activity. After infusion, the signal from transgenic T cells in peripheral blood increased up to 100-fold as measured by quantitative polymerase chain reaction for the transgene, with a corresponding increase in the frequency of functional LMP-specific T cells. Expansion was not associated with any acute or long-term toxicity. DNRII-LSTs persisted for up to ≥ 4 years. Four of the seven evaluable patients with active disease achieved clinical responses that were complete and ongoing in two patients at > 4 years, including in one patient who achieved only a partial response to unmodified tumor-directed T cells. Conclusion TGF-β-resistant tumor-specific T cells safely expand and persist in patients with Hodgkin lymphoma without lymphodepleting chemotherapy before infusion. DNRII-LSTs can induce complete responses even in patients with resistant disease. Expression of DNRII may be useful for the many other tumors that exploit this potent immune evasion mechanism.

Patients with primary immunodeficiency disorders (PID) have an increased risk from acute and chronic Epstein-Barr Virus (EBV) viral infections and EBV-associated malignancies. Hematopoietic stem cell transplantation (HSCT) is a curative strategy for many patients with PID, but EBV-related complications are common in the immediate post-transplant period due to delayed reconstitution of T cell immunity. Adoptive T cell therapy with EBV-specific T cells is a promising therapeutic strategy for patients with PID both before and after HSCT. Here we review the methods used to manufacture EBV-specific T cells, the clinical outcomes, and the ongoing challenges for future development of the strategy.

Mucormycosis is responsible for an increasing proportion of deaths after allogeneic bone marrow transplantation. Because this disease is associated with severe immunodeficiency and has shown resistance to even the newest antifungal agents, we determined the feasibility of reactivating and expanding Rhizopus oryzae -specific T cells for use as adoptive immunotherapy in transplant recipients. R. oryzae extract - pulsed monocytes were used to stimulate peripheral blood mononuclear cells from healthy donors, in the presence of different cytokine combinations. The generated R. oryzae -specific T cell products were phenotyped after the third stimulation and further characterized by the use of antibodies that block class I/II molecules, as well as pattern recognition receptors. Despite the very low frequency of R. oryzae -specific T cells of healthy donors, we found that stimulation with interleukin-2 (IL-2)/IL-7 cytokine combination could expand these rare cells. The expanded populations included 17%-83% CD4 + T cells that were specific for R. oryzae antigens. Besides interferon-γ (IFN-γ), these cells secreted IL-5, IL-10, IL-13, and tumor necrosis factor alpha (TNF-α), and recognized fungal antigens presented by HLA-II molecules rather than through nonspecific signaling. The method described herein is robust and reproducible, and could be used to generate adequate quantities of activated R. oryzae -specific T cells for clinical testing of safety and antifungal efficacy in patients with mucormycosis.

Virus infection remains an appreciable cause of morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Although pharmacotherapy and/or antibody therapy may help prevent or treat viral disease, these drugs are expensive, toxic, and often ineffective due to primary or secondary resistance. Further, effective treatments are limited for many infections (eg, adenovirus, BK virus), which are increasingly detected after alternative donor transplants. These deficiencies in conventional therapeutics have increased interest in an immunotherapeutic approach to viral disorders, leading to adoptive transfer of virus-specific cytotoxic T lymphocytes (VSTs), which can rapidly reconstitute antiviral immunity post-transplantation without causing graft-versus-host disease. This review will explore how the VST field has improved outcomes for many patients with life-threatening viral infections after HSCT, and how to broaden applicability beyond the "patient-specific" products, as well as extending to other viral diseases even outside the context of HSCT., (Copyright © 2018. Published by Elsevier Inc.)

Human papilloma virus (HPV) is a known cause of cervical cancer, squamous cell carcinoma and laryngeal cancer. Although treatments exist for HPV-associated malignancies, patients unresponsive to these therapies have a poor prognosis. Recent findings from vaccine studies suggest that T-cell immunity is essential for disease control. Because Epstein-Barr Virus (EBV)-specific T cells have been highly successful in treating or preventing EBV-associated tumors, we hypothesized that the development of a manufacturing platform for HPV-specific T cells from healthy donors could be used in a third-party setting to treat patients with high-risk/relapsed HPV-associated cancers. Most protocols for generating virus-specific T cells require prior exposure of the donor to the targeted virus and, because the seroprevalence of high-risk HPV types varies greatly by age and ethnicity, manufacturing of donor-derived HPV-specific T cells has proven challenging. We, therefore, made systematic changes to our current Good Manufacturing Practice (GMP)-compliant protocols to improve antigen presentation, priming and expansion for the manufacture of high-efficacy HPV-specific T cells. Like others, we found that current methodologies fail to expand HPV-specific T cells from most healthy donors. By optimizing dendritic cell maturation and function with lipopolysaccharide (LPS) and interferon (IFN)γ, adding interleukin (IL)-21 during priming and depleting memory T cells, we achieved reliable expansion of T cells specific for oncoproteins E6 and E7 to clinically relevant amounts (mean, 578-fold expansion; n = 10), which were polyfunctional based on cytokine multiplex analysis. In the third-party setting, such HPV-specific T-cell products might serve as a potent salvage therapy for patients with HPV-associated diseases., (Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Acute dynamic exercise mobilizes CD34+ hematopoietic stem cells (HSCs) to the bloodstream, potentially serving as an economical adjuvant to boost the collection of HSCs from stem cell transplant donors. The mechanisms responsible for HSC mobilization with exercise are unknown but are likely due to hemodynamic perturbations, endogenous granulocyte-colony stimulating factor (G-CSF), and/or β 2 -adrenergic receptor (β 2 -AR) signaling. We characterized the temporal response of HSC mobilization and plasma G-CSF following exercise, and determined the impact of in vivo β-AR blockade on the exercise-induced mobilization of HSCs. Healthy runners (n = 15) completed, in balanced order, two single bouts of steady state treadmill running exercise at moderate (lasting 90-min) or vigorous (lasting 30-min) intensity. A separate cohort of healthy cyclists (n = 12) completed three 30-min cycling ergometer trials at vigorous intensity after ingesting: (i) 10 mg bisoprolol (β 1 -AR antagonist); (ii) 80 mg nadolol (β 1  + β 2 -AR antagonist); or (iii) placebo, in balanced order with a double-blind design. Blood samples collected before, during (runners only), immediately after, and at several points during exercise recovery were used to determine circulating G-CSF levels (runners only) and enumerate CD34+ HSCs by flow cytometry (runners and cyclists). Steady state vigorous but not moderate intensity exercise mobilized HSCs, increasing the total blood CD34+ count by ∼4.15 ± 1.62 Δcells/µl (+202 ± 92%) compared to resting conditions. Plasma G-CSF increased in response to moderate but not vigorous exercise. Relative to placebo, nadolol and bisoprolol lowered exercising heart rate and blood pressure to comparable levels. The number of CD34+ HSCs increased with exercise after the placebo and bisoprolol trials, but not the nadolol trial, suggesting β 2 -AR signaling mediated the mobilization of CD34+ cells [Placebo: 2.10 ± 1.16 (207 ± 69.2%), Bisoprolol 1.66 ± 0.79 (+163 ± 29%), Nadolol: 0.68 ± 0.54 (+143 ± 36%) Δcells/µL]. We conclude that the mobilization of CD34+ HSCs with exercise is not dependent on circulating G-CSF and is likely due to the combined actions of β 2 -AR signaling and hemodynamic shear stress., (Copyright © 2017. Published by Elsevier Inc.)

The presence of persistent, latent HIV reservoirs in CD4+ T cells obstructs current efforts to cure infection. The so-called kick-and-kill paradigm proposes to purge these reservoirs by combining latency-reversing agents with immune effectors such as cytotoxic T lymphocytes. Support for this approach is largely based on success in latency models, which do not fully reflect the makeup of latent reservoirs in individuals on long-term antiretroviral therapy (ART). Recent studies have shown that CD8+ T cells have the potential to recognize defective proviruses, which comprise the vast majority of all infected cells, and that the proviral landscape can be shaped over time due to in vivo clonal expansion of infected CD4+ T cells. Here, we have shown that treating CD4+ T cells from ART-treated individuals with combinations of potent latency-reversing agents and autologous CD8+ T cells consistently reduced cell-associated HIV DNA, but failed to deplete replication-competent virus. These CD8+ T cells recognized and potently eliminated CD4+ T cells that were newly infected with autologous reservoir virus, ruling out a role for both immune escape and CD8+ T cell dysfunction. Thus, our results suggest that cells harboring replication-competent HIV possess an inherent resistance to CD8+ T cells that may need to be addressed to cure infection.

Virus infection remains an appreciable cause of morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Although pharmacotherapy and/or antibody therapy may help prevent or treat viral disease, these drugs are expensive, toxic, and often ineffective due to primary or secondary resistance. Further, effective treatments are limited for many infections (eg, adenovirus, BK virus), which are increasingly detected after alternative donor transplants. These deficiencies in conventional therapeutics have increased interest in an immunotherapeutic approach to viral disorders, leading to adoptive transfer of virus-specific cytotoxic T lymphocytes (VSTs), which can rapidly reconstitute antiviral immunity post-transplantation without causing graft-versus-host disease. This review will explore how the VST field has improved outcomes for many patients with life-threatening viral infections after HSCT, and how to broaden applicability beyond the "patient-specific" products, as well as extending to other viral diseases even outside the context of HSCT., (Copyright © 2017 The American Society for Blood and Marrow Transplantation. All rights reserved.)

Background: Haemopoietic stem-cell transplantation (HSCT) eradicates host haemopoiesis before venous infusion of haemopoietic stem cells (HSCs). The pathway to cellular recovery has been difficult to study in human beings because of risks associated with interventions during aplasia. We investigated whether 18 F-fluorothymidine ( 18 F-FLT) imaging was safe during allogenic HSCT and allowed visualisation of early cellular proliferation and detection of patterns of cellular engraftment after HSCT., Methods: Eligible patients were aged 18-55 years, had high-risk haematological malignancies. All patients underwent myeloablation followed by HSCT. The imaging primary endpoint was detection of early subclinical engraftment after HSCT with 18 F-FLT PET or CT. Imaging was done 1 day before and 5 or 9, and 28 days, and 1 year after HSCT. This study is registered with ClinicalTrials.gov, number NCT01338987., Findings: Between April 1, 2014, and Dec 31, 2015, 23 patients were enrolled and assessable for toxic effects after completing accrual. 18 F-FLT was not associated with any adverse events or delayed engraftment. 18 F-FLT imaging objectively identified subclinical bone-marrow recovery within 5 days of HSC infusion, which was up to 20 days before engraftment became clinically evident. Quantitatively, 18 F-FLT intensity differed significantly between myeloablative infusion before HSCT and subclinical HSC recovery (p=0·00031). 18 F-FLT biodistribution over time revealed a previously unknown path of cellular recovery of haemopoiesis in vivo that mirrored fetal ontogeny., Interpretation: 18 F-FLT allowed quantification and tracking of subclinical bone-marrow repopulation in human beings and revealed new insights into the biology of HSC recovery after HSCT., Funding: National Institutes of Health, Ben's Run/Ben's Gift, Albert and Elizabeth Tucker Foundation, Mex Frates Leukemia Fund, Jones Family fund, and Oklahoma Center for Adult Stem Cell Research., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

T-cell therapy has emerged from the bench for the treatment of patients with lymphoma. Responses to T-cell therapeutics are regulated by multiple factors, including the patient's immune system status and disease stage. Outside of engineering of chimeric antigen receptors and artificial T-cell receptors, T-cell therapy can be mediated by ex vivo expansion of antigen-specific T cells targeting viral and/or nonviral tumor-associated antigens. These approaches are contributing to enhanced clinical responses and overall survival. In this review, we summarize the available T-cell therapeutics beyond receptor engineering for the treatment of patients with lymphoma., Competing Interests: Conflict-of-interest disclosure: C.M.B. is a member on the board of directors or an advisory committee for Cellectis and Neximmune and has consulted for Neximmune. M.G. declares no competing financial interests. Off-label drug use: None disclosed.

Treatment with dose-adjusted EPOCH (etoposide, doxorubicin, cyclophosphamide, vincristine, prednisone) chemotherapy and rituximab (DA-EPOCH-R) has become the standard of care for primary mediastinal B-cell lymphoma (PMBCL) at many institutions despite limited data in the multi-centre setting. We report a large, multi-centre retrospective analysis of children and adults with PMBCL treated with DA-EPOCH-R to characterize outcomes and evaluate prognostic factors. We assessed 156 patients with PMBCL treated with DA-EPOCH-R across 24 academic centres, including 38 children and 118 adults. All patients received at least one cycle of DA-EPOCH-R. Radiation therapy was administered in 14·9% of patients. With median follow-up of 22·6 months, the estimated 3-year event-free survival (EFS) was 85·9% [95% confidence interval (CI) 80·3-91·5] and overall survival was 95·4% (95% CI 91·8-99·0). Outcomes were not statistically different between paediatric and adult patients. Thrombotic complications were reported in 28·2% of patients and were more common in paediatric patients (45·9% vs. 22·9%, P = 0·011). Seventy-five per cent of patients had a negative fluorodeoxyglucose positron emission tomography (FDG-PET) scan at the completion of DA-EPOCH-R, defined as Deauville score 1-3. Negative FDG-PET at end-of-therapy was associated with improved EFS (95·4% vs. 54·9%, P < 0·001). Our data support the use of DA-EPOCH-R for the treatment of PMBCL in children and adults. Patients with a positive end-of-therapy FDG-PET scan have an inferior outcome., (© 2017 John Wiley & Sons Ltd.)

While progress has been made in the treatment of both hematologic cancers and solid tumors, chemorefractory or relapsed disease often portends a dismal prognosis, and salvage chemotherapy or radiation expose patients to intolerable toxicities and may not be effective. Hematopoietic stem cell transplant offers the promise of cure for many patients, and while mismatched, unrelated or haploidentical donors are increasingly available, the recipients are at higher risk of severe immunosuppression and immune dysregulation due to graft versus host disease. Viral infections remain a primary cause of severe morbidity and mortality in this patient population. Again, many therapeutic options for viral disease are toxic, may be ineffective or generate resistance, or fail to convey long-term protection. Adoptive cell therapy with virus-specific T cells (VSTs) is a targeted therapy that is efficacious and has minimal toxicity in immunocompromised patients with CMV and EBV infections in particular. Products have since been generated specific for multiple viral antigens (multi-VST), which are not only effective but also confer protection in 70-90% of recipients when used as prophylaxis. Notably, these products can be generated from either virus-naive or virus-experienced autologous or allogeneic sources, including partially matched HLA-matched third-party donors. Obstacles to effective VST treatment are donor availability and product generation time. Banking of third-party VST is an attractive way to overcome these constraints and provide products on an as-needed basis. Other developments include epitope discovery to broaden the number of viral antigens targets in a single product, the optimization of VST generation from naive donor sources, and the modification of VSTs to enhance persistence and efficacy in vivo .

Latently human immunodeficiency virus (HIV)-infected cells are transcriptionally quiescent and invisible to clearance by the immune system. To demonstrate that the latency reversing agent vorinostat (VOR) induces a window of vulnerability in the latent HIV reservoir, defined as the triggering of viral antigen production sufficient in quantity and duration to allow for recognition and clearance of persisting infection, we developed a latency clearance assay (LCA). The LCA is a quantitative viral outgrowth assay (QVOA) that includes the addition of immune effectors capable of clearing cells expressing viral antigen. Here we show a reduction in the recovery of replication-competent virus from VOR exposed resting CD4 T cells following addition of immune effectors for a discrete period., Take Home Message: VOR exposure leads to sufficient production of viral protein on the cell surface, creating a window of vulnerability within this latent reservoir in antiretroviral therapy (ART)-suppressed HIV-infected individuals that allows the clearance of latently infected cells by an array of effector mechanisms., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Targeting CD30 with monoclonal antibodies in Hodgkin lymphoma (HL) and anaplastic large cell lymphoma (ALCL) has had profound clinical success. However, adverse events, mainly mediated by the toxin component of the conjugated antibodies, cause treatment discontinuation in many patients. Targeting CD30 with T cells expressing a CD30-specific chimeric antigen receptor (CAR) may reduce the side effects and augment antitumor activity., Methods: We conducted a phase I dose escalation study in which 9 patients with relapsed/refractory HL or ALCL were infused with autologous T cells that were gene-modified with a retroviral vector to express the CD30-specific CAR (CD30.CAR-Ts) encoding the CD28 costimulatory endodomain. Three dose levels, from 0.2 × 108 to 2 × 108 CD30.CAR-Ts/m2, were infused without a conditioning regimen. All other therapy for malignancy was discontinued at least 4 weeks before CD30.CAR-T infusion. Seven patients had previously experienced disease progression while being treated with brentuximab., Results: No toxicities attributable to CD30.CAR-Ts were observed. Of 7 patients with relapsed HL, 1 entered complete response (CR) lasting more than 2.5 years after the second infusion of CD30.CAR-Ts, 1 remained in continued CR for almost 2 years, and 3 had transient stable disease. Of 2 patients with ALCL, 1 had a CR that persisted 9 months after the fourth infusion of CD30.CAR-Ts. CD30.CAR-T expansion in peripheral blood peaked 1 week after infusion, and CD30.CAR-Ts remained detectable for over 6 weeks. Although CD30 may also be expressed by normal activated T cells, no patients developed impaired virus-specific immunity., Conclusion: CD30.CAR-Ts are safe and can lead to clinical responses in patients with HL and ALCL, indicating that further assessment of this therapy is warranted., Trial Registration: ClinicalTrials.gov NCT01316146., Funding: National Cancer Institute (3P50CA126752, R01CA131027 and P30CA125123), National Heart, Lung, and Blood Institute (R01HL114564), and Leukemia and Lymphoma Society (LLSTR 6227-08).

Hematopoietic stem cell (HSC) transplantation and adoptive transfer immunotherapy are effective in treating blood cancers and posttransplant infections, but low-circulating cell numbers in patients and donors are oftentimes a limiting factor. We postulate that a single exercise bout will increase the yield of patient- and donor-derived HSCs and cytotoxic lymphocytes to improve this form of treatment for cancer patients.

Bone marrow-derived mesenchymal stromal cells (BMSCs) are primitive, supportive cells of the bone marrow with tri-lineage potential to differentiate into bone, cartilage, fat and muscle. These cells possess both in vitro and in vivo immunomodulatory and wound-healing properties. Several studies have demonstrated efficacy of intravenously administered BMSCs in treating acute graft-versus-host disease (GvHD). Use of intravenous (IV) BMSCs in inflammatory bowel diseases (IBD) in humans has been limited to small studies in adults, but results have been promising. There remain many unanswered questions regarding safety, tolerability, effectiveness and optimal use of BMSCs to treat IBD, particularly in immunocompromised patients. This article reviews the evidence for using BMSCs to treat acute GvHD and how this experience may inform the potential use of BMSCs as a treatment for IBD., (Copyright © 2017 International Society for Cellular Therapy. All rights reserved.)

Umbilical cord blood transplant (CBT) has traditionally been associated with slower engraftment of neutrophils, delayed immune reconstitution and consequently higher risk of infections as compared with peripheral blood progenitor cell (PBPC) or bone marrow (BM) transplants. This is primarily due to low numbers of total nucleated cells (TNCs) and the naive nature of CB immune cells. The use of double unit CB transplant (DCBT) increases the total cell dose in the graft, but it still does not produce as rapid engraftment as seen with PBPC or even BM transplants. Herein, we discuss strategies to improve engraftment after CBT. We describe methods of (I) expansion of CB graft ex vivo to increase the total cell dose; and (II) enhancement of BM homing capability of CB progenitor cells; (III) ex vivo expansion of CB derived T cells for improving T cell function against viruses, tumors and protection from graft versus host disease (GVHD). With these novel approaches, engraftment after CBT is now reaching levels comparable to that of other graft types., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Umbilical cord blood (CB) has emerged as an effective alternative donor source for hematopoietic stem cell transplantation. Despite this success, the prolonged duration of immune suppression following CB transplantation and the naiveté of CB T cells leave patients susceptible to viral infections. Adoptive transfer of ex vivo-expanded virus-specific T cells from CB is both feasible and safe. However, the manufacturing process of these cells is complicated, lengthy, and labor-intensive. We have now developed a simplified method to manufacture a single culture of polyclonal multivirus-specific cytotoxic T cells in less than 30 days. It eliminates the need for a live virus or transduction with a viral vector, thus making this approach widely available and GMP-applicable to target multiple viruses. The use of overlapping PepMixes as a source of antigen stimulation enable expansion of the repertoire of the T cell product to any virus of interest and make it available as a third party "off the shelf" treatment for viral infections following transplantation.