Approaches for bridging therapy prior to chimeric antigen receptor T cells for relapsed/refractory acute lymphoblastic B-lineage leukaemia in children and young adults.

The ongoing development of immunotherapies, including chimeric antigen receptor (CAR) T cells, has revolutionized cancer treatment. In paediatric relapsed/refractory B-lineage acute leukaemia antiCD19-CARs induced impressive initial response rates, with event-free survival plateauing at 30-50% in long-term follow-up data. During the interval between diagnosis of relapse or refractoriness and CAR T cell infusion, patients require a bridging therapy. To date, this therapy has consisted of highly variable approaches based on local experience. Here, in an European collaborative effort of paediatric and adult haematologists, we summarise current knowledge with the aim of establishing a guidance for bridging therapy. This includes treatment strategies for different patient subgroups, the advantages and disadvantages of low- and highintensity regimens, and the potential impact of bridging therapy on outcome after CAR T cell infusion. This guidance is a step towards a cross-institutional harmonization of bridging therapy, including personalized approaches. This will allow better comparability of clinical data and increase the level of evidence for the treatment of children and young adults with relapsed/refractory B-lineage ALL until CAR T cell infusion.

[Early Detection Of Type 1 Diabetes By Islet Autoantibody Screening: A Position Paper Of The Fr1daplex Project Leaders And Training Centres, Bvkj Bavaria And Paednetz (Registered) Bavaria]. / Früherkennung von Typ-1-Diabetes durch Inselautoantikörper-Screening ­ ein Positionspapier der Fr1daPlex-Projektleiter und -Schulungszentren, des BVKJ Bayern und PaedNetz Bayern e.V.

This position paper is based on the authors' many years of clinical experience and basic science research on the diagnosis and treatment of children and adolescents with a presymptomatic early stage of type 1 diabetes. The benefits as well as potential disadvantages of early detection of type 1 diabetes by islet autoantibody screening are critically discussed. In addition, the perspectives of delaying the onset of the clinical metabolic disease through treatment with teplizumab are addressed. Today, we see the chance for a relevant improvement in therapeutic options and life perspectives of affected children and adolescents. Important next steps for the implementation of islet autoantibody screening in Germany are the training of pediatricians who should inform families about the screening, establishment of a few transregional laboratories that carry out the test, and expansion of regional capacities for the training and care of children with an early stage of type 1 diabetes.

Neonatal therapy after maternal central neurotropic drug exposure-a retrospective cohort study.

OBJECTIVE: Evaluation of neonatal morbidity after maternal central neurotropic drug exposure. METHODS: Retrospective single-center level-III neonatology cohort analysis of neonates after CND from 2018 to 2021. Control group of neonates born to mothers without CND cared for at the maternity ward. RESULTS: Significantly more frequent therapy need of neonates with CND [OR 23 (95% CI: 7.8-62); RR 14 (95% CI: 5.4-37); p < 0.01]. Neonates after CND had lower Apgar-scores LM 1 [CND 8.1; CG 8.6; p < 0.05]; LM 5 [CND 9; CG 9.7; p < 0.01]; LM 10 [CND 9.6; CG 9.9; p < 0.05]. The first symptom occurred in 95.35% within 24 h (mean: 3.3 h). CND group showed significantly more often preterm delivery [OR 3.5; RR 3.2; p < 0.05], and especially cumulative multiple symptoms [OR 9.4; RR 6.6; p < 0.01] but no correlation to multiple maternal medication use (p = 0.3). CONCLUSIONS: Neonates exposed to CND are at increased risk for postnatal therapy, often due to multiple symptoms. Neonates should be continuously monitored for at least 24 h.

YB-1-based oncolytic virotherapy in combination with CD47 blockade enhances phagocytosis of pediatric sarcoma cells.

Oncolytic viruses (OVs) selectively replicate in tumor cells resulting in lysis, spreading of new infectious units and induction of antitumor immune responses through abrogating an immunosuppressive tumor microenvironment (TME). Due to their mode of action, OVs are ideal combination partners with targeted immunotherapies. One highly attractive combination is the inhibition of the 'don't-eat-me'-signal CD47, which is known to increase the phagocytic potential of tumor-associated macrophages. In this work, we analyzed the combination approach consisting of the YB-1-based oncolytic adenovirus XVir-N-31 (XVir) and the CD47 inhibitor (CD47i) B6.H12.2 concerning its phagocytic potential. We investigate phagocytosis of XVir-, adenovirus wildtype (AdWT)-, and non-infected established pediatric sarcoma cell lines by different monocytic cells. Phagocytes (immature dendritic cells and macrophages) were derived from THP-1 cells and healthy human donors. Phagocytosis of tumor cells was assessed via FACS analysis in the presence and absence of CD47i. Additional characterization of T cell-stimulatory surface receptors as well as chemo-/cytokine analyses were performed. Furthermore, tumor cells were infected and studied for the surface expression of the 'eat-me'-signal calreticulin (CALR) and the 'don't-eat-me'-signal CD47. We herein demonstrate that (1) XVir-infected tumor cells upregulate both CALR and CD47. XVir induces higher upregulation of CD47 than AdWT. (2) XVir-infection enhances phagocytosis in general and (3) the combination of XVir and CD47i compared to controls showed by far superior enhancement of phagocytosis, tumor cell killing and innate immune activation. In conclusion, the combination of CD47i and XVir causes a significant increase in phagocytosis exceeding the monotherapies considerably accompanied by upregulation of T cell-stimulatory receptor expression and inflammatory chemo/-cytokine secretion.

TCR-transgenic T cells and YB-1-based oncolytic virotherapy improve survival in a preclinical Ewing sarcoma xenograft mouse model.

Background: Ewing sarcoma (EwS) is an aggressive and highly metastatic bone and soft tissue tumor in pediatric patients and young adults. Cure rates are low when patients present with metastatic or relapsed disease. Therefore, innovative therapy approaches are urgently needed. Cellular- and oncolytic virus-based immunotherapies are on the rise for solid cancers. Methods: Here, we assess the combination of EwS tumor-associated antigen CHM1319-specific TCR-transgenic CD8+ T cells and the YB-1-driven (i.e. E1A13S-deleted) oncolytic adenovirus XVir-N-31 in vitro and in a xenograft mouse model for antitumor activity and immunostimulatory properties. Results: In vitro both approaches specifically kill EwS cell lines in a synergistic manner over controls. This effect was confirmed in vivo, with increased survival using the combination therapy. Further in vitro analyses of immunogenic cell death and antigen presentation confirmed immunostimulatory properties of virus-infected EwS tumor cells. As dendritic cell maturation was also increased by XVir-N-31, we observed superior proliferation of CHM1319-specific TCR-transgenic CD8+ T cells only in virus-tested conditions, emphasizing the superior immune-activating potential of XVir-N-31. Conclusion: Our data prove synergistic antitumor effects in vitro and superior tumor control in a preclinical xenograft setting. Combination strategies of EwS-redirected T cells and YB-1-driven virotherapy are a highly promising immunotherapeutic approach for EwS and warrant further evaluation in a clinical setting.

The Eµ-Ret mouse is a novel model of hyperdiploid B-cell acute lymphoblastic leukemia.

The presence of supernumerary chromosomes is the only abnormality shared by all patients diagnosed with high-hyperdiploid B cell acute lymphoblastic leukemia (HD-ALL). Despite being the most frequently diagnosed pediatric leukemia, the lack of clonal molecular lesions and complete absence of appropriate experimental models have impeded the elucidation of HD-ALL leukemogenesis. Here, we report that for 23 leukemia samples isolated from moribund Eµ-Ret mice, all were characterized by non-random chromosomal gains, involving combinations of trisomy 9, 12, 14, 15, and 17. With a median gain of three chromosomes, leukemia emerged after a prolonged latency from a preleukemic B cell precursor cell population displaying more diverse aneuploidy. Transition from preleukemia to overt disease in Eµ-Ret mice is associated with acquisition of heterogeneous genomic abnormalities affecting the expression of genes implicated in pediatric B-ALL. The development of abnormal centrosomes in parallel with aneuploidy renders both preleukemic and leukemic cells sensitive to inhibitors of centrosome clustering, enabling targeted in vivo depletion of leukemia-propagating cells. This study reveals the Eµ-Ret mouse to be a novel tool for investigating HD-ALL leukemogenesis, including supervision and selection of preleukemic aneuploid clones by the immune system and identification of vulnerabilities that could be targeted to prevent relapse.