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1.
Nature ; 630(8015): 59-63, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750357

RESUMO

Ab initio calculations have an essential role in our fundamental understanding of quantum many-body systems across many subfields, from strongly correlated fermions1-3 to quantum chemistry4-6 and from atomic and molecular systems7-9 to nuclear physics10-14. One of the primary challenges is to perform accurate calculations for systems where the interactions may be complicated and difficult for the chosen computational method to handle. Here we address the problem by introducing an approach called wavefunction matching. Wavefunction matching transforms the interaction between particles so that the wavefunctions up to some finite range match that of an easily computable interaction. This allows for calculations of systems that would otherwise be impossible owing to problems such as Monte Carlo sign cancellations. We apply the method to lattice Monte Carlo simulations15,16 of light nuclei, medium-mass nuclei, neutron matter and nuclear matter. We use high-fidelity chiral effective field theory interactions17,18 and find good agreement with empirical data. These results are accompanied by insights on the nuclear interactions that may help to resolve long-standing challenges in accurately reproducing nuclear binding energies, charge radii and nuclear-matter saturation in ab initio calculations19,20.

2.
Phys Rev Lett ; 132(6): 062501, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38394570

RESUMO

We present a parameter-free ab initio calculation of the α-particle monopole transition form factor in the framework of nuclear lattice effective field theory. We use a minimal nuclear interaction that was previously used to reproduce the ground state properties of light nuclei, medium-mass nuclei, and neutron matter simultaneously with no more than a few percent error in the energies and charge radii. The results for the monopole transition form factor are in good agreement with recent precision data from Mainz.

3.
Phys Rev Lett ; 132(23): 232502, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905669

RESUMO

We present the first ab initio lattice calculations of spin and density correlations in hot neutron matter using high-fidelity interactions at next-to-next-to-next-to-leading order in chiral effective field theory. These correlations have a large impact on neutrino heating and shock revival in core-collapse supernovae and are encapsulated in functions called structure factors. Unfortunately, calculations of structure factors using high-fidelity chiral interactions were well out of reach using existing computational methods. In this Letter, we solve the problem using a computational approach called the rank-one operator (RO) method. The RO method is a general technique with broad applications to simulations of fermionic many-body systems. It solves the problem of exponential scaling of computational effort when using perturbation theory for higher-body operators and higher-order corrections. Using the RO method, we compute the vector and axial static structure factors for hot neutron matter as a function of temperature and density. The ab initio lattice results are in good agreement with virial expansion calculations at low densities but are more reliable at higher densities. Random phase approximation codes used to estimate neutrino opacity in core-collapse supernovae simulations can now be calibrated with ab initio lattice calculations.

4.
Phys Rev Lett ; 132(16): 162502, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38701465

RESUMO

The nuclear charge radius of ^{32}Si was determined using collinear laser spectroscopy. The experimental result was confronted with ab initio nuclear lattice effective field theory, valence-space in-medium similarity renormalization group, and mean field calculations, highlighting important achievements and challenges of modern many-body methods. The charge radius of ^{32}Si completes the radii of the mirror pair ^{32}Ar-^{32}Si, whose difference was correlated to the slope L of the symmetry energy in the nuclear equation of state. Our result suggests L≤60 MeV, which agrees with complementary observables.

6.
Am J Hematol ; 99(5): 890-899, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38444268

RESUMO

Natural killer (NK)-cells have potent anti-tumor effects, yet it remains unclear if they are effective for patients with relapsed acute myeloid leukemia (AML). In a phase I clinical trial, we treated 12 patients (median age 60 years) with refractory AML (median 5 lines of prior therapy, median bone marrow blast count of 47%) with fludarabine/cytarabine followed by 6 infusions of NK-cells expanded from haploidentical donors using K562 feeder cells expressing membrane-bound IL21 and 4-1BBL. Patients received 106-107/kg/dose. No toxicity or graft-versus-host disease (GVHD) was observed and MTD was not reached. Seven patients (58.3%) responded and achieved a complete remission (CR) with/without count recovery. Median time to best response was 48 days. Five responding patients proceeded to a haploidentical transplant from the same donor. After a median follow-up of 52 months, 1-year overall survival (OS) for the entire group was 41.7%, better for patients who responded with CR/CRi (57.14%), and for patients who responded and underwent transplantation (60%). Persistence and expansion of donor-derived NK-cells were identified in patients' blood, and serum IFNγ levels rose concurrently with NK cell infusions. A higher count-functional inhibitory KIR was associated with higher likelihood of achieving CR/CRi. In conclusion, we observed a significant response to ex vivo expanded NK-cell administration in refractory AML patients without adverse effects.


Assuntos
Doença Enxerto-Hospedeiro , Leucemia Mieloide Aguda , Humanos , Pessoa de Meia-Idade , Células Matadoras Naturais/patologia , Doença Enxerto-Hospedeiro/etiologia , Citarabina , Haplótipos
7.
Phys Rev Lett ; 131(24): 242503, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38181156

RESUMO

Quantum Monte Carlo simulations are powerful and versatile tools for the quantum many-body problem. In addition to the usual calculations of energies and eigenstate observables, quantum Monte Carlo simulations can in principle be used to build fast and accurate many-body emulators using eigenvector continuation or design time-dependent Hamiltonians for adiabatic quantum computing. These new applications require something that is missing from the published literature, an efficient quantum Monte Carlo scheme for computing the inner product of ground state eigenvectors corresponding to different Hamiltonians. In this work, we introduce an algorithm called the floating block method, which solves the problem by performing Euclidean time evolution with two different Hamiltonians and interleaving the corresponding time blocks. We use the floating block method and nuclear lattice simulations to build eigenvector continuation emulators for energies of ^{4}He, ^{8}Be, ^{12}C, and ^{16}O nuclei over a range of local and nonlocal interaction couplings. From the emulator data, we identify the quantum phase transition line from a Bose gas of alpha particles to a nuclear liquid.

8.
Mol Ther Oncol ; 32(2): 200820, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38933492

RESUMO

The prognosis for children with recurrent and/or refractory neuroblastoma (NB) is dismal. The receptor tyrosine kinase-like orphan receptor 1 (ROR1), which is highly expressed on the surface of NB cells, provides a potential target for novel immunotherapeutics. Anti-ROR1 chimeric antigen receptor engineered ex vivo expanded peripheral blood natural killer (anti-ROR1 CAR exPBNK) cells represent this approach. N-803 is an IL-15 superagonist with enhanced biological activity. In this study, we investigated the in vitro and in vivo anti-tumor effects of anti-ROR1 CAR exPBNK cells with or without N-803 against ROR1+ NB models. Compared to mock exPBNK cells, anti-ROR1 CAR exPBNK cells had significantly enhanced cytotoxicity against ROR1+ NB cells, and N-803 further increased cytotoxicity. High-dimensional analysis revealed that N-803 enhanced Stat5 phosphorylation and Ki67 levels in both exPBNK and anti-ROR1 CAR exPBNK cells with or without NB cells. In vivo, anti-ROR1 CAR exPBNK plus N-803 significantly (p < 0.05) enhanced survival in human ROR1+ NB xenografted NSG mice compared to anti-ROR1 CAR exPBNK alone. Our results provide the rationale for further development of anti-ROR1 CAR exPBNK cells plus N-803 as a novel combination immunotherapeutic for patients with recurrent and/or refractory ROR1+ NB.

9.
Leukemia ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969731

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) is a hematological malignancy arising from immature thymocytes. Unlike well-known oncogenic transcription factors, such as NOTCH1 and MYC, the involvement of chromatin remodeling factors in T-ALL pathogenesis is poorly understood. Here, we provide compelling evidence on how SWI/SNF chromatin remodeling complex contributes to human T-ALL pathogenesis. Integrative analysis of transcriptomic and ATAC-Seq datasets revealed high expression of SMARCA4, one of the subunits of the SWI/SNF complex, in T-ALL patient samples and cell lines compared to normal T cells. Loss of SMARCA protein function resulted in apoptosis induction and growth inhibition in multiple T-ALL cell lines. ATAC-Seq analysis revealed a massive reduction in chromatin accessibility across the genome after the loss of SMARCA protein function. RUNX1 interacts with SMARCA4 protein and co-occupies the same genomic regions. Importantly, the NOTCH1-MYC pathway was primarily affected when SMARCA protein function was impaired, implicating SWI/SNF as a novel therapeutic target.

10.
bioRxiv ; 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38464161

RESUMO

We previously reported that the DNA alkylator and transcriptional-blocking chemotherapeutic agent trabectedin enhances oncolytic herpes simplex viroimmunotherapy in human sarcoma xenograft models, though the mechanism remained to be elucidated. Here we report trabectedin disrupts the intrinsic cellular anti-viral response which increases viral transcript spread throughout the human tumor cells. We also extended our synergy findings to syngeneic murine sarcoma models, which are poorly susceptible to virus infection. In the absence of robust virus replication, we found trabectedin enhanced viroimmunotherapy efficacy by reducing immunosuppressive macrophages and stimulating granzyme expression in infiltrating T and NK cells to cause immune-mediated tumor regressions. Thus, trabectedin enhances both the direct virus-mediated killing of tumor cells and the viral-induced activation of cytotoxic effector lymphocytes to cause tumor regressions across models. Our data provide a strong rationale for clinical translation as both mechanisms should be simultaneously active in human patients.

11.
J Exp Clin Cancer Res ; 43(1): 193, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992659

RESUMO

BACKGROUND: Macrophages play important roles in phagocytosing tumor cells. However, tumors escape macrophage phagocytosis in part through the expression of anti-phagocytic signals, most commonly CD47. In Ewing sarcoma (ES), we found that tumor cells utilize dual mechanisms to evade macrophage clearance by simultaneously over-expressing CD47 and down-regulating cell surface calreticulin (csCRT), the pro-phagocytic signal. Here, we investigate the combination of a CD47 blockade (magrolimab, MAG) to inhibit the anti-phagocytic signal and a chemotherapy regimen (doxorubicin, DOX) to enhance the pro-phagocytic signal to induce macrophage phagocytosis of ES cells in vitro and inhibit tumor growth and metastasis in vivo. METHODS: Macrophages were derived from human peripheral blood monocytes by granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF). Flow cytometry- and microscopy-based in-vitro phagocytosis assays were performed to evaluate macrophage phagocytosis of ES cells. Annexin-V assay was performed to evaluate apoptosis. CD47 was knocked out by CRISPR/Cas9 approach. ES cell-based and patient-derived-xenograft (PDX)-based mouse models were utilized to assess the effects of MAG and/or DOX on ES tumor development and animal survival. RNA-Seq combined with CIBERSORTx analysis was utilized to identify changes in tumor cell transcriptome and tumor infiltrating immune cell profiling in MAG and/or DOX treated xenograft tumors. RESULTS: We found that MAG significantly increased macrophage phagocytosis of ES cells in vitro (p < 0.01) and had significant effect on reducing tumor burden (p < 0.01) and increasing survival in NSG mouse model (p < 0.001). The csCRT level on ES cells was significantly enhanced by DOX in a dose- and time-dependent manner (p < 0.01). Importantly, DOX combined with MAG significantly enhanced macrophage phagocytosis of ES cells in vitro (p < 0.01) and significantly decreased tumor burden (p < 0.01) and lung metastasis (p < 0.0001) and extended animal survival in vivo in two different mouse models of ES (p < 0.0001). Furthermore, we identified CD38, CD209, CD163 and CD206 as potential markers for ES-phagocytic macrophages. Moreover, we found increased M2 macrophage infiltration and decreased expression of Cd209 in the tumor microenvironment of MAG and DOX combinatorial therapy treated tumors. CONCLUSIONS: By turning "two keys" simultaneously to reactivate macrophage phagocytic activity, our data demonstrated an effective and highly translatable alternative therapeutic approach utilizing innate (tumor associated macrophages) immunotherapy against high-risk metastatic ES.


Assuntos
Imunoterapia , Macrófagos , Sarcoma de Ewing , Sarcoma de Ewing/imunologia , Sarcoma de Ewing/patologia , Sarcoma de Ewing/terapia , Sarcoma de Ewing/tratamento farmacológico , Animais , Camundongos , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Imunoterapia/métodos , Antígeno CD47/metabolismo , Linhagem Celular Tumoral , Fagocitose , Ensaios Antitumorais Modelo de Xenoenxerto , Feminino , Imunidade Inata , Modelos Animais de Doenças
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