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Objectives Adoptive immunotherapy using donor‐derived antigen‐specific T‐cells can prevent and treat infection after allogeneic haemopoietic stem cell transplant (HSCT). Methods We treated 11 patients with a prophylactic infusion of 2 × 107 cells per square metre donor‐derived T‐cells targeting seven infections (six viral and one fungal) following HSCT. Targeted pathogens were cytomegalovirus (CMV), Epstein–Barr virus (EBV), adenovirus, varicella zoster virus, influenza, BK virus (BKV) and Aspergillus fumigatus. Results T‐cell products were successfully generated in all patients with 10 products responsive to 6 or 7 infections. T‐cell infusions were associated with increases in antigen‐experienced activated CD8+ T‐cells by day 30. CMV, EBV and BKV reactivation occurred in the majority of patients and was well controlled except where glucocorticoids were administered soon after T‐cell infusion. Three patients in that circumstance developed CMV tissue infection. No patient required treatment for invasive fungal infection. The most common CMV and EBV TCR clonotypes in the infusion product became the most common clonotypes seen at day 30 post‐T‐cell infusion. Donors and their recipients were recruited to the study prior to transplant. Grade III/IV graft‐versus‐host disease developed in four patients. At a median follow‐up of 390 days post‐transplant, six patients had died, 5 of relapse, and 1 of multi‐organ failure. Infection did not contribute to death in any patient. Conclusion Rapid reconstitution of immunity to a broad range of viral and fungal infections can be achieved using a multi‐pathogen‐specific T‐cell product. The development of GVHD after T‐cell infusion suggests that infection‐specific T‐cell therapy after allogeneic stem cell transplant should be combined with other strategies to reduce graft‐versus‐host disease., In this study, 12 patients were treated with ex vivo expanded donor‐derived T‐cells specific for seven virus and fungal pathogens. There was no acute infusion‐related toxicity. CD8 T‐cell numbers in the peripheral blood rose within 30 days of infusion. Graft‐versus‐host disease and corticosteroid use were associated with viral reactivation; no patient developed fungal disease. Relapse (n = 5) and multi‐organ failure (n = 1) were the causes of death. Infection did not contribute to death in any patient.

Donor-derived adoptive T-cell therapy is a safe and effective treatment of viral infection posttransplant, but it is limited by donor serostatus and availability and by its personalized nature. Off-the-shelf, third-party virus-specific T cells (VSTs) appear promising, but the long-term safety and durability of responses have yet to be established. We conducted a prospective study of 30 allogeneic hemopoietic stem cell transplant (HSCT) patients with persistent or recurrent cytomegalovirus (CMV) (n = 28), Epstein-Barr virus (n = 1), or adenovirus (n = 1) after standard therapy. Patients were treated with infusions of partially HLA-matched, third-party, ex vivo-expanded VSTs (total = 50 infusions) at a median of 75 days post-HSCT (range, 37 to 349 days). Safety, viral dynamics, and immune recovery were monitored for 12 months. Infusions were safe and well tolerated. Acute graft versus host disease occurred in 2 patients, despite a median HLA match between VSTs and the recipient of 2 of 6 antigens. At 12 months, the cumulative incidence of overall response was 93%. Virological control was durable in the majority of patients; the reintroduction of antiviral therapy after the final infusion occurred in 5 patients. CMV-specific T-cell immunity rose significantly and coincided with a rise in CD8+ terminal effector cells. PD-1 expression was elevated on CD8+ lymphocytes before the administration of third-party T cells and remained elevated at the time of viral control. Third-party VSTs show prolonged benefit, with virological control achieved in association with the recovery of CD8+ effector T cells possibly facilitated by VST infusion. This trial was registered at www.clinicaltrials.gov as #NCT02779439 and www.anzctr.org.au as #ACTRN12613000603718.

Increasing dose intensity (DI) of chemotherapy for patients with aggressive non-Hodgkin lymphoma (NHL) may improve outcomes at the cost of increased toxicity. This issue was addressed in a randomized trial aiming to double the DI of myelosuppressive drugs. Between 1994 and 1999, 250 patients with previously untreated aggressive NHL were randomized to treatment with six cycles of 3-weekly standard (s) or intensive (i) chemotherapy: s-CEOP–cyclophosphamide 750, epirubicin 75, vincristine 1.4 mg/m2 all on day 1, and prednisolone 100 mg days 1–5; i-CEOP–cyclophosphamide 1,500, epirubicin 150, vincristine 1.4 mg/m2 all on day 1, and prednisolone 100 mg days 1–5. Primary endpoint was 5-year overall survival (OS). Relative to s-CEOP patients, i-CEOP patients achieved a 78% increase in the DI of cyclophosphamide and epirubicin. Despite this, there was no significant difference in any outcome: 5-year OS (56.7% i-CEOP; 55.1% s-CEOP; P = 0.80), 5-year progression free survival (PFS; 41% i-CEOP; 43% s-CEOP; P = 0.73), 5-year time to progression (TTP; 44% i-CEOP; 47% s-CEOP; P = 0.72), or complete remission (CR) + unconfirmed CR (CRu) rates (53% i-CEOP; 59% s-CEOP; P = 0.64). Long-term follow up at 10 years also showed no significant differences in OS, PFS, or TTP. The i-CEOP arm had higher rates of febrile neutropenia (70 vs. 26%), hospitalisations, blood product utilisation, haematological and gastrointestinal toxicities, and lower quality of life scores during treatment, although without significant differences 6-month later. In the treatment of aggressive NHL in the prerituximab era, increasing DI did not result in improved outcomes, while at the same time lead to increased toxicity. Am. J. Hematol. 89:536–541, 2014. © 2014 Wiley Periodicals, Inc.

We investigated the use of adoptively transferred donor-derived cytomegalovirus (CMV) specific cytotoxic T lymphocytes (CTL) as immune reconstitution postallogeneic transplant in a phase 2 study. Fifty patients were infused with a single dose of 2 × 10(7)cells/m(2) after day 28 post-transplant. Twenty-six patients reactivated CMV posttransplant (only 5 post-CTL infusion) and 9 required therapy with ganciclovir or foscarnet (only 1 post-CTL infusion). There was 1 case of fatal CMV disease, attributable to high levels of antithymocyte globulin at the time of T cell infusion. We compared the patients in the phase 2 study with a group of contemporaneous controls also treated at the trial centers. There was no increase in acute or chronic graft-versus-host disease attributable to CTL infusion; overall and progression-free survival were similar in both groups. There was a reduction in the percentage of patients who required CMV directed antiviral therapy (17% vs 36%, P = .01) and in the total number of treatment days in the cohort receiving CTL (3.4 days vs 8.9 days, P = .03) without a reduction in CMV reactivation rates. We postulate that adoptively transferred cells are able to expand in response to viral antigen, limit viral replication, and prevent progression to tissue infection. This study was registered on the Australian Clinical Trial Registry as #ACTRN12605000213640 and #ACTRN12607000224426.

Background aims Protocols for the production of CD19-specific chimeric antigen receptor (CAR19) T cells are often complex and expensive because of the use of retroviral and lentiviral vectors or the need for CAR19 T-cell enrichment. We aimed to simplify the generation of CAR19 T cells from the peripheral blood of normal donors and patients using the piggyBac transposon system of gene modification. Methods We varied electroporation voltage, cytokines and stimulation conditions for the generation and expansion of CAR19 T cells over a 3-week culture period. Results Using optimized electroporation voltage, interleukin-15 alone and co-culturing CAR T cells with peripheral blood mononuclear cells, we were able to expand CAR19 T-cell cultures by up to 765-fold over 3 weeks in normal donors and 180-fold in patients with B-cell malignancies. Final median CAR19 expression of 72% was seen in normal donors, and 81% was seen in patients with acute lymphoblastic leukaemia, chronic lymphocytic leukemia or non-Hodgkin lymphoma. CAR19 T cells produced interferon gamma on stimulation with CD19 + cell lines and efficiently lysed both CD19 + cell lines and primary leukemia cells. In addition, combining CAR expression with an inducible caspase safety switch allowed elimination of CAR19 T cells by the application of a small molecule dimerizer. Discussion We have produced a simple, inexpensive and easily adoptable protocol for the generation of CAR19 T cells suitable for use in clinical trials using the piggyBac transposon system. This provides a robust platform for further enhancing the T-cell product and testing new CAR technologies.

Increasing dose intensity (DI) of chemotherapy for patients with aggressive non-Hodgkin lymphoma (NHL) may improve outcomes at the cost of increased toxicity. This issue was addressed in a randomized trial aiming to double the DI of myelosuppressive drugs. Between 1994 and 1999, 250 patients with previously untreated aggressive NHL were randomized to treatment with six cycles of 3-weekly standard (s) or intensive (i) chemotherapy: s-CEOP-cyclophosphamide 750, epirubicin 75, vincristine 1.4 mg/m(2) all on day 1, and prednisolone 100 mg days 1-5; i-CEOP-cyclophosphamide 1,500, epirubicin 150, vincristine 1.4 mg/m(2) all on day 1, and prednisolone 100 mg days 1-5. Primary endpoint was 5-year overall survival (OS). Relative to s-CEOP patients, i-CEOP patients achieved a 78% increase in the DI of cyclophosphamide and epirubicin. Despite this, there was no significant difference in any outcome: 5-year OS (56.7% i-CEOP; 55.1% s-CEOP; P = 0.80), 5-year progression free survival (PFS; 41% i-CEOP; 43% s-CEOP; P = 0.73), 5-year time to progression (TTP; 44% i-CEOP; 47% s-CEOP; P = 0.72), or complete remission (CR) + unconfirmed CR (CRu) rates (53% i-CEOP; 59% s-CEOP; P = 0.64). Long-term follow up at 10 years also showed no significant differences in OS, PFS, or TTP. The i-CEOP arm had higher rates of febrile neutropenia (70 vs. 26%), hospitalisations, blood product utilisation, haematological and gastrointestinal toxicities, and lower quality of life scores during treatment, although without significant differences 6-month later. In the treatment of aggressive NHL in the prerituximab era, increasing DI did not result in improved outcomes, while at the same time lead to increased toxicity.

Since 2003 we have treated 101 patients with antigen specific T cells for treatment or prevention of opportunistic infections in the context of haemopoietic progenitor cell (HPC) and solid organ transplant. Over this time, we have modified laboratory procedures to progressively incorporate T cell therapy into standard transplant practice. We have increased the number of pathogen targets, utilised HPC products and streamlined culture techniques. We are now able to produce a multipathogen product within 3 weeks of HPC harvest in a manner consistent with good manufacturing practice and within the scope of systems established for HPC processing. Our approach could be used by most accredited transplant laboratories.We have developed robust, simple and inexpensive methods that use marrow or G-CSF mobilised HPC products as starting material for T cell expansion. This has major practical importance in minimising repeated donor screening, blood draws and apheresis. Our current procedure uses monocyte derived dendritic cells (mo-DC) isolated using a modified CD14 selection method that requires minimal quantities of CD14 selection reagent. Maturation of mo-DCs utilises GM-CSF, IL-4, PG-E2, IL-6 and IL-1β. Multiple antigens are presented to T cells by mo-DCs including peptide mixes for cytomegalovirus (CMV), Epstein Barr virus (EBV), BK virus and adenovirus, vaccines (Varicella Zoster and Influenza virus) and mycelial lysate (Aspergillus). Activated antigen specific T cells are expanded using IL-2. We use no T cell selection/depletion procedures, feeder layers, cytokine, tetramer capture or clinical grade sorting methodologies. The overall cost of manufacture of each product, including reagents, staffing and ongoing infrastructure costs is approximately AU$2400 per dose.The phenotypic composition of multipathogen products is mainly CD3 (mean 97%, range 90-97), with variable CD4:8 ratio, minimal contaminating B cells (mean 0.1%), monocytes (mean 0.3%) and NK cells (mean 3%). We have demonstrated antigen specificity using intracellular cytokine staining, MHC multimer analysis (CMV and EBV), interferon-γ Elispot and chromium (Cr51) release cytotoxicity assay. Products do not show alloreactivity by Cr51 release assay (Mean 0.8% specific lysis at E:T ratio of 20:1, range 0-5.3).Clinical results of the first 50 patients treated with CMV specific T cells have previously been reported and showed infusion to be safe and to reduce the need for CMV-directed antiviral therapy. Clinical outcomes of the remaining patients treated with multi-pathogen T cells specific for up to 8 pathogens will be reported when data is mature.Future areas of development will involve extension of the range of infectious pathogens targeted, addition of cells targeting malignant antigens and combination of these therapies with CD34+ stem cell selection. Developing progressively greater selectivity through graft engineering and immunotherapy will improve outcomes of transplantation in the future.