TP3 binding domain mutations are bad news in Burkitt lymphoma.

Not available.

Risk Factors Associated with Survival Following Ganciclovir Prophylaxis through Day +100 in Cytomegalovirus At-Risk Pediatric Allogeneic Stem Cell Transplantation Recipients: Development of Cytomegalovirus Viremia Associated with Significantly Decreased 1-Year Survival.

Cytomegalovirus (CMV) reactivation is a major cause of morbidity and nonrelapse mortality (NRM) in pediatric allogeneic stem cell transplantation (alloSCT) recipients. Approximately 80% of CMV seropositive alloHCT recipients will experience CMV reactivation without prophylaxis. The impacts of ganciclovir prophylaxis and subsequent CMV viremia on 1-year survival and 1-year NRM are unknown. The primary objective of this study was to determine the effect of CMV viremia on the probability of 1-year survival and 1-year NRM in pediatric alloSCT recipients receiving 100 days of ganciclovir prophylaxis. The secondary objective was to determine the effect of other risk factors on 1-year survival and 1-year NRM. All patients age 0 to 26 years who underwent alloSCT between June 2011 and May 2020 and received ganciclovir prophylaxis for 100 days at Westchester Medical Center, an academic medical center, were analyzed. Ganciclovir was administered to at-risk alloSCT recipients (donor and or recipient CMV+ serostatus) as 5 mg/kg every 12 hours from the first day of conditioning through day -1 (recipient CMV+ only) followed by 6 mg/kg every 24 hours on Monday through Friday beginning on the day of an absolute neutrophil count >750/mm3 and continuing through day +100. National Cancer Institute Common Terminology Criteria for Adverse Events 5.0 criteria were used to grade toxicity. NRM was analyzed using competing survival analysis with relapse death as a competing event. The log-rank and Gray tests were performed to compare the 1-year survival probabilities and NRM cumulative incidence between patients who experienced CMV viremia post-alloSCT and those who did not. Univariate Cox regression analysis was performed for the following risk factors: CMV viremia, donor source, sex, malignant disease, disease risk index, conditioning intensity, receipt of rabbit antithymocyte globulin (rATG)/alemtuzumab, graft-versus-host disease (GVHD) prophylaxis, CMV donor/recipient serostatus, grade II-IV acute GVHD, and grade 3/4 neutropenia necessitating discontinuation of ganciclovir, treating the last 3 factors as time-dependent covariates. Those with P values < .2 were included in the multivariate Cox regression analysis. Eighty-four alloSCT recipients (41 males, 43 females; median age, 10.8 years [range, .4 to 24.4 years]) were analyzed. Multivariate analysis showed significantly lower 1-year survival and significantly higher 1-year NRM in patients who developed CMV viremia compared to those who did not (P = .0036). No other risk factors were significantly associated with 1-year survival or 1-year NRM. One-year survival was significantly decreased and 1-year NRM was significantly increased in pediatric alloSCT recipients who developed CMV viremia following ganciclovir prophylaxis. No other risk factors were found to be associated with 1-year survival or 1-year NRM. Alternative CMV prophylaxis regimens that reduce CMV viremia should be investigated in pediatric alloSCT recipients at risk for CMV infection.

A humanized orthotopic mouse model for preclinical evaluation of immunotherapy in Ewing sarcoma.

The advent of novel cancer immunotherapy approaches is revolutionizing the treatment for cancer. Current small animal models for most cancers are syngeneic or genetically engineered mouse models or xenograft models based on immunodeficient mouse strains. These models have been limited in evaluating immunotherapy regimens due to the lack of functional human immune system. Development of animal models for bone cancer faces another challenge in the accessibility of tumor engraftment sites. Here, we describe a protocol to develop an orthotopic humanized mouse model for a bone and soft tissue sarcoma, Ewing sarcoma, by transplanting fresh human cord blood CD34+ hematopoietic stem cells into young NSG-SGM3 mice combined with subsequent Ewing sarcoma patient derived cell engraftment in the tibia of the humanized mice. We demonstrated early and robust reconstitution of human CD45+ leukocytes including T cells, B cells, natural killer cells and monocytes. Ewing sarcoma xenograft tumors successfully orthotopically engrafted in the humanized mice with minimal invasive procedures. We validated the translational utility of this orthotopic humanized model by evaluating the safety and efficacy of an immunotherapy antibody, magrolimab. Treatment with magrolimab induces CD47 blockade resulting in significantly decreased primary tumor growth, decreased lung metastasis and prolonged animal survival in the established humanized model. Furthermore, the humanized model recapitulated the dose dependent toxicity associated with the CD47 blockade as observed in patients in clinical trials. In conclusion, this orthotopic humanized mouse model of Ewing sarcoma represents an improved platform for evaluating immunotherapy in bone and soft tissue sarcoma, such as Ewing sarcoma. With careful design and optimization, this model is generalizable for other bone malignancies.

Inflammation-mediated fibroblast activation and immune dysregulation in collagen VII-deficient skin.

Inflammation is known to play a critical role in all stages of tumorigenesis; however, less is known about how it predisposes the tissue microenvironment preceding tumor formation. Recessive dystrophic epidermolysis bullosa (RDEB), a skin-blistering disease secondary to COL7A1 mutations and associated with chronic wounding, inflammation, fibrosis, and cutaneous squamous cell carcinoma (cSCC), models this dynamic. Here, we used single-cell RNA sequencing (scRNAseq) to analyze gene expression patterns in skin cells from a mouse model of RDEB. We uncovered a complex landscape within the RDEB dermal microenvironment that exhibited altered metabolism, enhanced angiogenesis, hyperproliferative keratinocytes, infiltration and activation of immune cell populations, and inflammatory fibroblast priming. We demonstrated the presence of activated neutrophil and Langerhans cell subpopulations and elevated expression of PD-1 and PD-L1 in T cells and antigen-presenting cells, respectively. Unsupervised clustering within the fibroblast population further revealed two differentiation pathways in RDEB fibroblasts, one toward myofibroblasts and the other toward a phenotype that shares the characteristics of inflammatory fibroblast subsets in other inflammatory diseases as well as the IL-1-induced inflammatory cancer-associated fibroblasts (iCAFs) reported in various cancer types. Quantitation of inflammatory cytokines indicated dynamic waves of IL-1α, TGF-ß1, TNF, IL-6, and IFN-γ concentrations, along with dermal NF-κB activation preceding JAK/STAT signaling. We further demonstrated the divergent and overlapping roles of these cytokines in inducing inflammatory phenotypes in RDEB patients as well as RDEB mouse-derived fibroblasts together with their healthy controls. In summary, our data have suggested a potential role of inflammation, driven by the chronic release of inflammatory cytokines such as IL-1, in creating an immune-suppressed dermal microenvironment that underlies RDEB disease progression.

Early Postnatal Expression of Tgfß-1 and Fgf-2 Correlates With Regenerative Functions of Unrestricted Somatic Stem Cell Infusion After Rabbit GMH-IVH.

Intraventricular hemorrhage (IVH) is a severe complication of preterm birth associated with white matter injury (WMI) and reduced neurogenesis. IVH commonly arises from the germinal matrix, a highly cellular, transient structure, where all precursor cells are born, proliferate, and migrate during brain development. IVH leads to reduced progenitor cell proliferation and maturation and contributes to WMI. Interruption of oligodendrocyte lineage (OL) proliferation and maturation after IVH will prevent myelination. We evaluated whether unrestricted somatic stem cells (USSCs) could recover OL lineage, as USSC release multiple relevant growth factors and cytokines. The effects of USSC infusion at 24 hours after IVH were assessed in the periventricular zone by analysis of OL lineage-specific progression (PDGFR+, OLIG2+, NKX2.2+ with Ki67), and this was correlated with growth factors TGFß1, FGF2 expression. The early OL cell lineage by immunofluorescence and cell density quantitation showed significant reduction after IVH (P < .05 both PDGFR+, OLIG2+ at day 3); with significant recovery after injection of USSCs (P < .05 both PDGFR+, OLIG2+ at day 3). CSF protein and tissue mRNA levels of TGFß1 were reduced by IVH and recovered after USSC (P < .05 for all changes). FGF2 showed an increased mRNA after USSC on day3 (P < .05). Cell cyclin genes were unaffected except for the cycle inhibitor P27Kip1 which increased after IVH but returned to normal after USSC on day 3. Our findings demonstrated a plausible mechanism through which USSCs can aid in developmental myelination by recovery of OL proliferation and maturation along with correlative changes in growth factors during brain development.

Expert consensus guidelines for the prophylaxis and management of tumor lysis syndrome in the United States: Results of a modified Delphi panel.

INTRODUCTION: Tumor lysis syndrome (TLS), which occurs spontaneously or in response to anticancer treatment, results in the release of intracellular potassium, phosphorus, and nucleic acids into the bloodstream, which results in secondary clinical complications that may be fatal. Prior TLS guidelines do not take into consideration potent novel oncologic agents or contemporary treatment paradigms with increased risk of TLS. Thus, a modified Delphi panel of experts was convened to provide an update for TLS management guidelines based upon a combination of supporting literature and practice consensus. METHODS: A three-round modified Delphi process was implemented. For round 1, nine expert panelists completed a web-based questionnaire developed using published literature. In round 2, panelists were asked to reconsider their answers to questions that did not reach consensus (defined as ≥ 66% agreement among voting panelists). Round 3 was an unblinded, moderated virtual meeting to discuss any remaining questions that did not reach consensus. RESULTS: Detailed recommendations are given for prophylaxis, monitoring, and management of TLS risks and complications, with hydration being a key element of TLS prophylaxis and management. Guidelines for the management of acute effects of TLS and prevention of long-term renal effects include management of hyperkalemia, hypocalcemia, hyperphosphatemia, and hyperuricemia. DISCUSSION: Although the control of uric acid levels is quite effective with currently available agents, panelists emphasize the importance of monitoring and treating other dangerous electrolyte abnormalities such as hyperkalemia and hyperphosphatemia. Guidelines from this modified Delphi panel should aid clinicians in preventing and managing TLS.

Children's Oncology Group's 2023 blueprint for research: Cellular therapy and stem cell transplantation.

Since the publication of the last Cellular Therapy and Stem Cell Transplant blueprint in 2013, Children's Oncology Group cellular therapy-based trials advanced the field and created new standards of care across a wide spectrum of pediatric cancer diagnoses. Key findings include that tandem autologous transplant improved survival for patients with neuroblastoma and atypical teratoid/rhabdoid brain tumors, one umbilical cord blood (UCB) donor was safer than two UCB donors, killer immunoglobulin receptor (KIR) mismatched donors did not improve survival for pediatric acute myeloid leukemia when in vivo T-cell depletion is used, and the depth of remission as measured by next-generation sequencing-based minimal residual disease assessment pretransplant was the best predictor of relapse for acute lymphoblastic leukemia. Plans for the next decade include optimizing donor selection for transplants for acute leukemia/myelodysplastic syndrome, using novel engineered cellular therapies to target a wide array of malignancies, and developing better treatments for cellular therapy toxicities such as viral infections and graft-vs-host disease.

Diagnosis and management of mature B-cell lymphomas in children, adolescents, and young adults.

Mature B-cell lymphoma in children, adolescents and young adults comprises three major histological subtypes including in order of frequency Burkitt, germinal center diffuse large B-cell lymphoma and primary mediastinal B-cell lymphoma. The cure rate of the first two with aggressive short chemotherapy based on clinical grouping is ∼90% in resource rich countries. Recent data has shown that incorporation of immune therapy has enhanced event free survival in advanced patients. Future studies will address the possibility of reducing the burden of chemotherapy by substitution of immune based therapies.

Cellular and humoral immunotherapy in children, adolescents and young adults with non-Hodgkin lymphoma.

The prognosis is dismal (2-year overall survival less than 25%) for childhood, adolescent, and young adult (CAYA) with relapsed and/or refractory (R/R) non-Hodgkin lymphoma (NHL). Novel targeted therapies are desperately needed for this poor-risk population. CD19, CD20, CD22, CD79a, CD38, CD30, LMP1 and LMP2 are attractive targets for immunotherapy in CAYA patients with R/R NHL. Novel anti-CD20 monoclonal antibodies, anti-CD38 monoclonal antibody, antibody drug conjugates and T and natural killer (NK)-cell bispecific and trispecific engagers are being investigated in the R/R setting and are changing the landscape of NHL therapy. A variety of cellular immunotherapies such as viral activated cytotoxic T-lymphocyte, chimeric antigen receptor (CAR) T-cells, NK and CAR NK-cells have been investigated and provide alternative options for CAYA patients with R/R NHL. Here, we provide an update and clinical practice guidance of utilizing these cellular and humoral immunotherapies in CAYA patients with R/R NHL.

Manufacture and Characterization of Good Manufacturing Practice-Compliant SARS-COV-2 Cytotoxic T Lymphocytes.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 virus-specific cytotoxic T-cell lymphocytes (vCTLs) could provide a promising modality in COVID-19 treatment. We aimed to screen, manufacture, and characterize SARS-CoV-2-vCTLs generated from convalescent COVID-19 donors using the CliniMACS Cytokine Capture System (CCS). METHODS: Donor screening was done by stimulation of convalescent COVID-19 donor peripheral blood mononuclear cells with viral peptides and identification of interferonγ (IFN-γ)+ CD4 and CD8 T cells using flow cytometry. Clinical-grade SARS-CoV-2-vCTLs were manufactured using the CliniMACS CCS. The enriched SARS-CoV-2-vCTLs were characterized by T-cell receptor sequencing, mass cytometry, and transcriptome analysis. RESULTS: Of the convalescent donor blood samples, 93% passed the screening criteria for clinical manufacture. Three validation runs resulted in enriched T cells that were 79% (standard error of the mean 21%) IFN-γ+ T cells. SARS-CoV-2-vCTLs displayed a highly diverse T-cell receptor repertoire with enhancement of both memory CD8 and CD4 T cells, especially in CD8 TEM, CD4 TCM, and CD4 TEMRA cell subsets. SARS-CoV-2-vCTLs were polyfunctional with increased gene expression in T-cell function, interleukin, pathogen defense, and tumor necrosis factor superfamily pathways. CONCLUSIONS: Highly functional SARS-CoV-2-vCTLs can be rapidly generated by direct cytokine enrichment (12 hours) from convalescent donors. CLINICAL TRIALS REGISTRATION: NCT04896606.

Donor chimerism and immune reconstitution following haploidentical transplantation in sickle cell disease.

Introduction: We previously reported the initial results of a phase II multicenter transplant trial using haploidentical parental donors for children and aolescents with high-risk sickle cell disease achieving excellent survival with exceptionally low rates of graft-versus-host disease and resolution of sickle cell disease symptoms. To investigate human leukocyte antigen (HLA) sensitization, graft characteristics, donor chimerism, and immune reconstitution in these recipients. Methods: CD34 cells were enriched using the CliniMACS® system with a target dose of 10 x 106 CD34+ cells/kg with a peripheral blood mononuclear cell (PBMNC) addback dose of 2x105 CD3/kg in the final product. Pre-transplant HLA antibodies were characterized. Donor chimerism was monitored 1-24 months post-transplant. Comprehensive assessment of immune reconstitution included lymphocyte subsets, plasma cytokines, complement levels, anti-viral T-cell responses, activation markers, and cytokine production. Infections were monitored. Results: HLA antibodies were detected in 7 of 11 (64%) evaluable patients but rarely were against donor antigens. Myeloid engraftment was rapid (100%) at a median of 9 days. At 30 days, donor chimerism was 93-99% and natural killer cell levels were restored. By 60 days, CD19 B cells were normal. CD8 and CD4 T-cells levels were normal by 279 and 365 days, respectively. Activated CD4 and CD8 T-cells were elevated at 100-365 days post-transplant while naïve cells remained below baseline. Tregs were elevated at 100-270 days post-transplant, returning to baseline levels at one year. At one year, C3 and C4 levels were above baseline and CH50 levels were near baseline. At one year, cytokine levels were not significantly different from baseline. Discussion: These results suggest that haploidentical transplantation with CD34-enriched cells and peripheral blood mononuclear cell addback results in rapid engraftment, sustained donor chimerism and broad-based immune reconstitution.

Pediatric versus adult high grade glioma: Immunotherapeutic and genomic considerations.

High grade gliomas are identified as malignant central nervous tumors that spread rapidly and have a universally poor prognosis. Historically high grade gliomas in the pediatric population have been treated similarly to adult high grade gliomas. For the first time, the most recent classification of central nervous system tumors by World Health Organization has divided adult from pediatric type diffuse high grade gliomas, underscoring the biologic differences between these tumors in different age groups. The objective of our review is to compare high grade gliomas in the adult versus pediatric patient populations, highlighting similarities and differences in epidemiology, etiology, pathogenesis and therapeutic approaches. High grade gliomas in adults versus children have varying clinical presentations, molecular biology background, and response to chemotherapy, as well as unique molecular targets. However, increasing evidence show that they both respond to recently developed immunotherapies. This review summarizes the distinctions and commonalities between the two in disease pathogenesis and response to therapeutic interventions with a focus on immunotherapy.

Concomitant Ruxolitinib and Ibrutinib for Graft-Versus-Host Disease (GVHD): The First Reported Use in Pediatric Patients.

Allogeneic hematopoietic stem cell transplant (alloHSCT) can be a life-saving treatment for patients with hematological disorders but far too often carries the feared complication of graft-versus-host disease (GVHD). The first-line treatment of GVHD is typically corticosteroids, but steroid-refractory chronic GVHD (cGVHD) has led to the Food and Drug Administration (FDA) approval of ruxolitinib (Jakafi), ibrutinib (Imbruvica), and belumosudil (Rezurock). Patient 1 was a four-year-old female diagnosed with natural killer (NK) cell dysfunction who underwent alloHSCT with cells from a 9/10 National Marrow Donor Program (NMDP) donor and subsequently developed chronic GVHD (cGVHD) of the skin and gut. This cGVHD was refractory to steroids and ibrutinib but improved with the administration of concomitant ibrutinib and ruxolitinib. Patient 2 was a one-year-old male with sickle cell anemia. The patient was transplanted under a haploidentical protocol from the mother but developed bronchiolitis obliterans organizing pneumonia (BOOP) and pathology-confirmed GVHD. This cGVHD was steroid-refractory and resolved with the administration of concomitant ibrutinib and ruxolitinib. To our knowledge, this is the first reported use of concomitant ruxolitinib and ibrutinib in pediatric patients. The combination was well tolerated with no significant adverse events. Neither patient had to discontinue these drugs. We propose a further investigation into this dual therapy in cGVHD either compared to steroids or as a second-line option.

KIR-favorable TCR-αß/CD19-depleted haploidentical HCT in children with ALL/AML/MDS: primary analysis of the PTCTC ONC1401 trial.

We performed a prospective multicenter study of T-cell receptor αß (TCR-αß)/CD19-depleted haploidentical hematopoietic cell transplantation (HCT) in children with acute leukemia and myelodysplastic syndrome (MDS), to determine 1-year disease-free survival (DFS) and compare 2-year outcomes with recipients of other donor cell sources. Fifty-one patients aged 0.7 to 21 years were enrolled; donors were killer immunoglobulin-like receptor (KIR) favorable based on ligand mismatch and/or high B content. The 1-year DFS was 78%. Superior 2-year DFS and overall survival (OS) were noted in patients <10 years of age, those treated with reduced toxicity conditioning (RTC) rather than myeloablative conditioning, and children with minimal residual disease <0.01% before HCT. Multivariate analysis comparing the KIR-favorable haploidentical cohort with controls showed similar DFS and OS compared with other donor cell sources. Multivariate analysis also showed a marked decrease in the risk of grades 2 to 4 and 3 to 4 acute graft versus host disease (aGVHD), chronic GVHD, and transplant-related mortality vs other donor cell sources. Ethnic and racial minorities accounted for 53% of enrolled patients, and data from a large cohort of recipients/donors screened for KIR showed that >80% of recipients had a KIR-favorable donor by our definition, demonstrating that this approach is broadly applicable to groups often unable to find donors. This prospective, multicenter study showed improved outcomes using TCR-αß/CD19-depleted haploidentical donors using RTC for children with acute leukemia and MDS. Randomized trials comparing this approach with matched unrelated donors are warranted. This trial was registered at https://clinicaltrials.gov as #NCT02646839.

Risk-adapted chemoimmunotherapy using brentuximab vedotin and rituximab in children, adolescents, and young adults with newly diagnosed Hodgkin's lymphoma: a phase II, non-randomized controlled trial.

BACKGROUND: Cure rates for Hodgkin's lymphoma are excellent, but excess short-term and long-term morbidities from treatment remain a concern. Immunotherapy targeting both tumor antigens and the immunosuppressive tumor microenvironment in children, adolescents, and young adults with Hodgkin's lymphoma may improve early response rates and eliminate toxic chemotherapy and radiation, thus minimizing toxicity. We conducted a phase II study to evaluate the safety and overall response rate of brentuximab vedotin and rituximab in combination with risk-adapted chemotherapy in children, adolescents, and young adults with newly diagnosed classic Hodgkin's lymphoma (cHL). METHODS: This is a prospective, phase II, non-randomized, risk-assigned study. Patients were treated and evaluated between 2012 and 2020. Eligible patients were aged ≥1 and ≤30 years old with advanced stage, intermediate-risk, and high-risk newly diagnosed cHL. Patients received four or six cycles of brentuximab vedotin (1.2 mg/kg), doxorubicin (25 mg/m2), vinblastine (6 mg/m2), dacarbazine (375 mg/m2), and rituximab (375 mg/m2). Early response was evaluated following two cycles of therapy. Involved field radiotherapy (IFRT) was restricted to high-risk patients with both bulky disease and slow response or those not in complete response at the end of chemoimmunotherapy. RESULTS: Thirty patients were enrolled, with a median age of 15 years (4-23). There were 18 intermediate-risk and 12 high-risk patients. Toxicities included grade III mucositis (3%), infusion reaction (3%), and peripheral neuropathy (6%). There was a 100% complete response rate on completion of chemoimmunotherapy. Eighteen patients (60%) achieved a rapid early response. Four patients (13%) required IFRT. The 5-year event-free and overall survival rates were 100%, with a median follow-up of 62 months (18-105). CONCLUSIONS: Immunotherapy with brentuximab vedotin, rituximab, and risk-adapted chemotherapy is safe in children, adolescents, and young adults with newly diagnosed cHL. We have demonstrated 100% complete response and 100% event-free and overall survival rates at a median 5-year follow-up, with a significant reduction in use of more toxic chemotherapy and IFRT. A larger cohort is required to confirm these preliminary findings. TRIAL REGISTRATION NUMBER: NCT02398240.

The Future of Natural Killer Cell Immunotherapy for B Cell Non-Hodgkin Lymphoma (B Cell NHL).

OPINION STATEMENT: Natural killer (NK) cells have played a critical-if largely unrecognized or ignored-role in the treatment of B cell non-Hodgkin lymphoma (NHL) since the introduction of CD20-directed immunotherapy with rituximab as a cornerstone of therapy over 25 years ago. Engagement with NK cells leading to lysis of NHL targets through antibody-dependent cellular cytotoxicity (ADCC) is a critical component of rituximab's mechanism of action. Despite this important role, the only aspect of B cell NHL therapy that has been adopted as standard therapy that even indirectly augments or restores NK cell function is the introduction of obinutuzumab, a CD20 antibody with enhanced ability to engage with NK cells. However, over the last 5 years, adoptive immunotherapy with effector lymphocytes of B cell NHL has experienced tremendous growth, with five different CAR T cell products now licensed by the FDA, four of which target CD19 and have approved indications for some subtype of B cell NHL-axicabtagene ciloleucel, brexucabtagene autoleucel, lisocabtagene maraleucel, and tisagenlecleucel. These T cell-based immunotherapies essentially mimic the recognition, activation pathway, and cytotoxic machinery of a CD19 antibody engaging NK cells and lymphoma targets. Despite their efficacy, these T cell-based immunotherapies have been difficult to implement because they require 4-6 weeks of manufacture, are costly, and have significant toxicities. This renewed interest in the potential of cellular immunity-and the manufacturing, supply chain, and administration logistics that have been addressed with these new agents-have ignited a new wave of enthusiasm for NK cell-directed therapies in NHL. With high safety profiles and proven anti-lymphoma efficacy, one or more new NK cell-directed modalities are certain to be introduced into the standard toolbox of NHL therapy within the next few years, be it function-enhancing cytokine muteins, multi-domain NK cell engagers, or adoptive therapy with expanded or genetically modified NK cells.