Current developments in T-cell receptor therapy for Acute Myeloid Leukaemia.

T-cell receptor (TCR) therapies are a promising modality for the treatment of cancers, with significant efforts being directed towards acute myeloid leukaemia (AML), a particularly challenging disease. Chimeric antigen receptor (CAR) T-cells targeting single surface antigens have shown remarkable efficacy for B-cell lymphoblastic leukaemia, lymphomas and multiple myeloma. However, AML presents formidable obstacles to the effectiveness of CAR T-cells due to the widespread expression of heterogenous leukaemia immunophenotypes and surface antigen targets additionally present on normal myeloid cells.

Intra-tumoral and peripheral blood TIGIT and PD-1 as immune biomarkers in nodular lymphocyte predominant Hodgkin lymphoma.

In classical Hodgkin lymphoma (cHL), responsiveness to immune-checkpoint blockade (ICB) is associated with specific tumor microenvironment (TME) and peripheral blood features. The role of ICB in nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is not established. To gain insights into its potential in NLPHL, we compared TME and peripheral blood signatures between HLs using an integrative multiomic analysis.

Indeterminate measurable residual disease by multiparameter flow cytometry is associated with an intermediate risk of clinical relapse in adult patients with acute leukaemia.

Measurable residual disease (MRD) is useful for prognostication and for monitoring response to treatment in patients with acute leukaemia. MRD by multiparametric flow cytometry (MFC-MRD) utilises the leukaemia-associated immunophenotype (LAIP) and difference from normal (DfN) strategies to identify the leukaemic clone. Difficulties arise when the LAIP overlaps with normal regeneration, there is clonal evolution, or when the abnormal clone population is exceptionally small e.

Anti-CD19 Chimeric Antigen Receptor T-Cell Therapy for Richter Transformation: An International, Multicenter, Retrospective Study.

Purpose: Outcomes for Richter transformation (RT) are poor with current therapies. The efficacy and safety of anti-CD19 chimeric antigen receptor T-cell therapy (CAR-T) for RT are not established.

Methods: We performed an international multicenter retrospective study of patients with RT who received CAR-T.

Circulating cytokine and chemokine patterns associated with cytomegalovirus reactivation after stem cell transplantation.

Objectives: Human cytomegalovirus (HCMV) reactivation is the leading viral complication after allogeneic haematopoietic stem cell transplantation (allo-HSCT). Understanding of circulating cytokine/chemokine patterns which accompany HCMV reactivation and correlate with HCMV DNAemia magnitude is limited. We aimed to characterise plasma cytokine/chemokine profiles in 36 allo-HSCT patients (21 with HCMV reactivation and 15 without HCMV reactivation) at four time-points in the first 100-day post-transplant.

CAR and CAR T cells share a differentiation trajectory into an NK-like subset after CD19 CAR T cell infusion in patients with B cell malignancies.

Chimeric antigen receptor (CAR) T cell therapy is effective in treating B cell malignancies, but factors influencing the persistence of functional CAR T cells, such as product composition, patients' lymphodepletion, and immune reconstitution, are not well understood. To shed light on this issue, here we conduct a single-cell multi-omics analysis of transcriptional, clonal, and phenotypic profiles from pre- to 1-month post-infusion of CAR and CAR T cells from patients from a CARTELL study (ACTRN12617001579381) who received a donor-derived 4-1BB CAR product targeting CD19. Following infusion, CAR T cells and CAR T cells shows similar differentiation profiles with clonally expanded populations across heterogeneous phenotypes, demonstrating clonal lineages and phenotypic plasticity.

Measurable Residual Disease (MRD) by Flow Cytometry in Adult B-Acute Lymphoblastic Leukaemia (B-ALL) and Acute Myeloid Leukaemia (AML): Correlation with Molecular MRD Testing and Clinical Outcome at One Year.

Measurable residual disease (MRD) detected by flow cytometry (FC) is well established in paediatric B- lymphoblastic leukaemia (B-ALL) and adult chronic lymphocytic leukaemia (CLL), but its utility in adult B-ALL and adult acute myeloid leukaemia (AML) is less clear. In this prospective MRD study, one of the largest in Australia to date, we examined consecutive bone marrow aspirates from adult participants with B-ALL ( = 47) and AML ( = 87) sent for FC-MRD testing at a quaternary referral hospital in Sydney. FC-MRD results were correlated to corresponding Mol-MRD testing where available and clinical outcomes at three-month intervals over 1 year.

Long-term outcomes of corticosteroid graft versus host disease prophylaxis in peripheral blood allogeneic haemopoietic stem cell transplant: a comparative cohort analysis.

Background: Corticosteroids (CSs) have previously been incorporated into graft versus host disease (GVHD) prophylaxis regimens for bone marrow (BM) and haemopoietic stem cell transplant (HSCT).

Aims: To assess the impact of prophylactic CS in HSCT using peripheral blood (PB) stem cells.

Methods: Patients were identified from three HSCT centres receiving a first PB-HSCT between January 2011 and December 2015 from a fully human leukocyte antigen (HLA)-matched sibling or unrelated donor for acute myeloid leukaemia or acute lymphoblastic leukaemia.

Australia and New Zealand Transplant and Cellular Therapies (ANZTCT) position statement: COVID-19 management in patients with haemopoietic stem cell transplant and chimeric antigen receptor T cell.

Patients with post-haemopoietic stem cell transplant or chimeric antigen receptor T -cell (CAR-T) therapy face a significant risk of morbidity and mortality from coronavirus disease 2019 because of their immunosuppressed state. As case numbers in Australia and New Zealand continue to rise, guidance on management in this high-risk population is needed. Whilst we have learned much from international colleagues who faced high infection rates early in the pandemic, guidance relevant to local health system structures, medication availability and emerging therapies is essential to equip physicians to manage our patients optimally.

Third-party CMV- and EBV-specific T-cells for first viral reactivation after allogeneic stem cell transplant.

Virus-specific T-cells (VSTs) from third-party donors mediate short- and long-term antiviral effects in allogeneic hematopoietic stem cell transplant (HSCT) recipients with relapsed or refractory viral infections. We investigated early administration of third-party VSTs, together with antiviral therapy in patients requiring treatment for first cytomegalovirus (CMV) or Epstein-Barr virus (EBV) infection. Thirty HSCT patients were treated with 1 to 4 VST infusions (2 × 107 cells/m2; CMV n=27, EBV n=3) at a median of 4 days after initiation of antiviral treatment.

Combining CD34+ stem cell selection with prophylactic pathogen and leukemia directed T-cell immunotherapy to simultaneously reduce graft versus host disease, infection, and leukemia recurrence after allogeneic stem cell transplant.

We designed a trial to simultaneously address the problems of graft versus host disease (GVHD), infection, and recurrence of malignancy after allogeneic stem cell transplantation. CD34 stem cell isolation was used to minimize the development of acute and chronic GVHD. Two prophylactic infusions, one combining donor-derived cytomegalovirus, Epstein-Barr virus, and Aspergillus fumigatus specific T-cells and the other comprising donor-derived CD19 directed chimeric antigen receptor (CAR) bearing T-cells, were given 21-28 days after transplant.

Immunoprofiling reveals cell subsets associated with the trajectory of cytomegalovirus reactivation post stem cell transplantation.

Human cytomegalovirus reactivation is a major opportunistic infection after allogeneic haematopoietic stem cell transplantation and has a complex relationship with post-transplant immune reconstitution. Here, we use mass cytometry to define patterns of innate and adaptive immune cell reconstitution at key phases of human cytomegalovirus reactivation in the first 100 days post haematopoietic stem cell transplantation. Human cytomegalovirus reactivation is associated with the development of activated, memory T-cell profiles, with faster effector-memory CD4 T-cell recovery in patients with low-level versus high-level human cytomegalovirus DNAemia.

treekoR: identifying cellular-to-phenotype associations by elucidating hierarchical relationships in high-dimensional cytometry data.

High-throughput single-cell technologies hold the promise of discovering novel cellular relationships with disease. However, analytical workflows constructed for these technologies to associate cell proportions with disease often employ unsupervised clustering techniques that overlook the valuable hierarchical structures that have been used to define cell types. We present treekoR, a framework that empirically recapitulates these structures, facilitating multiple quantifications and comparisons of cell type proportions.

Beyond antivirals: virus-specific T-cell immunotherapy for BK virus haemorrhagic cystitis and JC virus progressive multifocal leukoencephalopathy.

Purpose Of Review: The clinical manifestations of the polyomaviruses BK and JC in immunocompromised patients include BK virus (BKV) induced haemorrhagic cystitis and nephropathy, and JC virus (JCV) associated progressive multifocal leukoencephalopathy (PML) and are typically a consequence of impaired adaptive immunity in the host. To date, little clinical success has been achieved with antiviral agents or other drug therapies to treat these conditions. Here we review the methods and outcomes of the most recent clinical studies utilising adoptive immunotherapy with BK and/or JC virus-specific T-cells (VST) as either prophylaxis or treatment alternatives.

Cytomegalovirus Infections in Children with Primary and Secondary Immune Deficiencies.

Cytomegalovirus (CMV) is a human herpes virus that causes significant morbidity and mortality in immunosuppressed children. CMV primary infection causes a clinically mild disease in healthy children, usually in early childhood; the virus then utilises several mechanisms to establish host latency, which allows for periodic reactivation, particularly when the host is immunocompromised. It is this reactivation that is responsible for the significant morbidity and mortality in immunocompromised children.

Investigation of product-derived lymphoma following infusion of piggyBac-modified CD19 chimeric antigen receptor T cells.

We performed a phase 1 clinical trial to evaluate outcomes in patients receiving donor-derived CD19-specific chimeric antigen receptor (CAR) T cells for B-cell malignancy that relapsed or persisted after matched related allogeneic hemopoietic stem cell transplant. To overcome the cost and transgene-capacity limitations of traditional viral vectors, CAR T cells were produced using the piggyBac transposon system of genetic modification. Following CAR T-cell infusion, 1 patient developed a gradually enlarging retroperitoneal tumor due to a CAR-expressing CD4+ T-cell lymphoma.

Successful treatment of Epstein-Barr virus-associated primary central nervous system lymphoma due to post-transplantation lymphoproliferative disorder, with ibrutinib and third-party Epstein-Barr virus-specific T cells.

Primary central nervous system lymphoma (PCNSL) occurring following organ transplantation (post-transplantation lymphoproliferative disorder [PTLD]) is a highly aggressive non-Hodgkin lymphoma. It is typically treated with high-dose methotrexate-based regimens. Outcomes are dismal and clinical trials are lacking.

Prophylactic antigen-specific T-cells targeting seven viral and fungal pathogens after allogeneic haemopoietic stem cell transplant.

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 × 10 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 .

Profiling the Blood Compartment of Hematopoietic Stem Cell Transplant Patients During Human Cytomegalovirus Reactivation.

Human cytomegalovirus (HCMV) is a widespread pathogen establishing a latent infection in its host. HCMV reactivation is a major health burden in immunocompromised individuals, and is a major cause of morbidity and mortality following hematopoietic stem cell transplantation (HSCT). Here we determined HCMV genomic levels using droplet digital PCR in different peripheral blood mononuclear cell (PBMC) populations in HCMV reactivating HSCT patients.

Identification of SARS-CoV-2 Nucleocapsid and Spike T-Cell Epitopes for Assessing T-Cell Immunity.

Developing optimal T-cell response assays to severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is critical for measuring the duration of immunity to this disease and assessing the efficacy of vaccine candidates. These assays need to target conserved regions of SARS-CoV-2 global variants and avoid cross-reactivity to seasonal human coronaviruses. To contribute to this effort, we employed an immunoinformatics analysis pipeline to identify immunogenic peptides resulting from conserved and highly networked regions with topological importance from the SARS-CoV-2 nucleocapsid and spike proteins.