Project description:Our study provides compelling support to an effective CAR-T cell anti-aging intervention using NMN, a key NAD+ intermediate. We found the clinical potential of NMN for CAR-T cell immunotherapy for human cancers, attributed to their central memory phenotype. The cells are more viable, proliferative, and long-lived in vivo. Furthermore, these CAR-T cells exerted great antitumor efficacy against tumors in human xenograft mouse models. Detailed molecular mechanisms responsible for the pleiotropic effects of NMN need to be investigated further. So RNA-seq was used to analyze the different gene expression of these CAR-T cells.
Project description:BackgroundAdoptive immunotherapy using T cells expressing chimeric antigen receptors (CARs) targeting CD19 has produced remarkable clinical outcomes. However, much of the mechanisms of action, such as the development of memory responses and sources of immune cytokines, remain elusive largely due to the challenge of characterizing human CAR T cell function in vivo. The lack of a suitable in vivo model also hinders the development of new CAR T cell therapies.MethodsWe established a humanized mouse (hu-mouse) model with a functional human immune system and genetically-matched (autologous) primary acute B-lymphoblastic leukemia (B-ALL) that permits modeling of CD19-targeted CAR T cell therapy in immunocompetent hosts without allogeneic or xenogeneic immune responses.FindingsAnti-CD19 CAR T cells were detected in blood of leukemic hu-mice with kinetics and levels similar to those seen in patients receiving CAR T cell therapy. The levels of CAR T cells were correlated inversely with the burden of leukemia cells and positively with the survival times in anti-CD19 CAR T cell-treated leukemic hu-mice. Infusion of anti-CD19 CAR T cells also resulted in rapid production of T cell- and monocyte/macrophage-derived cytokines and an increase in frequency of regulatory T cells as reported in clinical studies.InterpretationThese results provide a proof-of-principle that this novel preclinical model has the potential to be used to model human CAR T cell therapy and facilitate the design of new CARs with improved antitumor activity.
Project description:B cell lymphoma therapy has been transformed by CD19-targeting cellular therapeutics that induce high clinical response rates and impressive remissions in relapsed and refractory patients. However, approximately half of all patients who respond to CD19-directed cell therapy relapse, the majority within 6 months. One characteristic of relapse is loss or reduction of CD19 expression on malignant B cells. We designed a unique therapeutic to prevent and reverse relapses due to lost or reduced CD19 expression. This novel biologic, a CAR T Engager, binds CD20 and displays the CD19 extracellular domain. This approach increases the apparent CD19 antigen density on CD19-positive/CD20-positive lymphoma cells, and prevents antigen-loss induced relapse, as CD19 bound to CD20 remains present on the cell surface. We demonstrate that this novel therapeutic prevents and reverses lymphoma relapse in vitro and prevents CD19-negative lymphoma growth and relapse in vivo.
Project description:To evaluate vaccine-induced humoral and cell-mediated immunity at 6 months after completion of two doses of BNT162b2 vaccination, immunoglobulin G against SARS-CoV-2 spike protein (SP IgG), 50% neutralizing antibody (NT50), and spot-forming cell (SFC) counts were evaluated by interferon-γ releasing ELISpot assay of 98 healthy subjects (median age, 43 years). The geometric mean titers of SP IgG and NT50 decreased from 95.2 (95% confidence interval (CI) 79.8-113.4) to 5.7 (95% CI 4.9-6.7) and from 680.4 (588.0-787.2) to 130.4 (95% CI 104.2-163.1), respectively, at 3 weeks and 6 months after the vaccination. SP IgG titer was negatively correlated with age and alcohol consumption. Spot-forming cell counts at 6 months did not correlate with age, gender, and other parameters of the patients. SP IgG, NT50, and SFC titers were elevated in the breakthrough infected subjects. Although the levels of vaccine-induced antibodies dramatically declined at 6 months after vaccination, a certain degree of cellular immunity was observed irrespective of the age.
Project description:Chimeric Antigen Receptor (CAR) T cell therapy has shown promise in treating hematologic malignancies. However, it is limited to individualized cell therapy and faces challenges, including high costs, extended preparation time, and limited efficacy against solid tumors. Here, we generated circular RNAs (circRNAs) encoding Chimeric Antigen Receptor (CAR) transmembrane proteins, referred to as circRNACAR, which mediated remarkable tumor killing in both T cells and macrophages. In addition, macrophages exhibited efficient phagocytosis of tumor cells and pro-inflammatory polarization induced by circRNACAR in vitro. We demonstrated that circRNACAR, delivered with immunocyte-tropic lipid nanoparticles (LNPs), significantly inhibited tumor growth, improved survival rates and induced a pro-inflammatory tumor microenvironment in mice. Importantly, the combination of circRNAAnti-HER2-CAR and circRNA-based cancer vaccines encoding the corresponding transmembrane HER2 antigen, termed circRNAHER2, exhibited synergistically enhanced anti-tumor activity. Notably, we found that circRNACAR could boost the level of circRNAHER2-elicited antibodies, which could mediate effective killing of HER2+ tumor cells by macrophages, indicating the potential of vaccination-elicited antibodies in developing novel immunotherapy. This proof-of-concept study demonstrated that the combination of circRNA-based in vivo CAR and vaccines, termed in vivo CAR-VAC, holds the potential to become an upgraded off-the-shelf immunotherapy, and also sheds light on the huge potential of vaccination-elicited antibodies in cancer immunotherapy.
Project description:Anti-CD19 chimeric antigen receptor (CAR) T cell therapies can cause severe cytokine-release syndrome (CRS) and neurotoxicity, impeding their therapeutic application. Here we generated a new anti-CD19 CAR molecule (CD19-BBz(86)) derived from the CD19-BBz prototype bearing co-stimulatory 4-1BB and CD3? domains. We found that CD19-BBz(86) CAR T cells produced lower levels of cytokines, expressed higher levels of antiapoptotic molecules and proliferated more slowly than the prototype CD19-BBz CAR T cells, although they retained potent cytolytic activity. We performed a phase 1 trial of CD19-BBz(86) CAR T cell therapy in patients with B cell lymphoma (ClinicalTrials.gov identifier NCT02842138 ). Complete remission occurred in 6 of 11 patients (54.5%) who each received a dose of 2?×?108-4?×?108 CD19-BBz(86) CAR T cells. Notably, no neurological toxicity or CRS (greater than grade 1) occurred in any of the 25 patients treated. No significant elevation in serum cytokine levels after CAR T cell infusion was detected in the patients treated, including in those who achieved complete remission. CD19-BBz(86) CAR T cells persistently proliferated and differentiated into memory cells in vivo. Thus, therapy with the new CD19-BBz(86) CAR T cells produces a potent and durable antilymphoma response without causing neurotoxicity or severe CRS, representing a safe and potent anti-CD19 CAR T cell therapy.
Project description:BackgroundIn December 2020, Israel began a mass vaccination campaign against coronavirus disease 2019 (Covid-19) by administering the BNT162b2 vaccine, which led to a sharp curtailing of the outbreak. After a period with almost no cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, a resurgent Covid-19 outbreak began in mid-June 2021. Possible reasons for the resurgence were reduced vaccine effectiveness against the delta (B.1.617.2) variant and waning immunity. The extent of waning immunity of the vaccine against the delta variant in Israel is unclear.MethodsWe used data on confirmed infection and severe disease collected from an Israeli national database for the period of July 11 to 31, 2021, for all Israeli residents who had been fully vaccinated before June 2021. We used a Poisson regression model to compare rates of confirmed SARS-CoV-2 infection and severe Covid-19 among persons vaccinated during different time periods, with stratification according to age group and with adjustment for possible confounding factors.ResultsAmong persons 60 years of age or older, the rate of infection in the July 11-31 period was higher among persons who became fully vaccinated in January 2021 (when they were first eligible) than among those fully vaccinated 2 months later, in March (rate ratio, 1.6; 95% confidence interval [CI], 1.3 to 2.0). Among persons 40 to 59 years of age, the rate ratio for infection among those fully vaccinated in February (when they were first eligible), as compared with 2 months later, in April, was 1.7 (95% CI, 1.4 to 2.1). Among persons 16 to 39 years of age, the rate ratio for infection among those fully vaccinated in March (when they were first eligible), as compared with 2 months later, in May, was 1.6 (95% CI, 1.3 to 2.0). The rate ratio for severe disease among persons fully vaccinated in the month when they were first eligible, as compared with those fully vaccinated in March, was 1.8 (95% CI, 1.1 to 2.9) among persons 60 years of age or older and 2.2 (95% CI, 0.6 to 7.7) among those 40 to 59 years of age; owing to small numbers, the rate ratio could not be calculated among persons 16 to 39 years of age.ConclusionsThese findings indicate that immunity against the delta variant of SARS-CoV-2 waned in all age groups a few months after receipt of the second dose of vaccine.
Project description:BackgroundSARS-CoV-2 breakthrough infections after complete vaccination are increasing whereas their determinants remain uncharacterized.MethodsWe analyzed two cases of post-vaccination SARS-CoV-2 infections by α and β variants, respectively. For each participant both humoral (binding and neutralizing antibodies) and cellular (activation markers and cytokine expression) immune responses were characterized longitudinally.ResultsThe first participant (P1) was infected by an α variant and displayed an extended and short period of viral excretion and symptom. Analysis of cellular and humoral response 72 h post-symptom onset revealed that P1 failed at developing neutralizing antibodies and a potent CD4 memory response (lack of SARS-CoV-2 specific CD4+IL-2+ cells) and CD8 effector response (CD8+IFNγ+ cells). The second participant (P2) developed post-vaccination SARS-CoV-2 infection by a β variant, associated with a short period of viral excretion and symptoms. Despite displaying initially high levels and polyfunctional T cell responses, P2 lacked initial β-directed neutralizing antibodies. Both participants developed and/or increased their neutralization activity and cellular responses against all variants, namely, β and δ variants that lasts up to 3 months after breakthrough infection.ConclusionsAn analysis of cellular and humoral response suggests two possible mechanisms of breakthrough infection: a poor immune response to vaccine and viral evasion to neutralizing antibodies.
Project description:Adoptive transfer of in vitro expanded, chimeric antigen receptor (CAR)-redirected CD19-specific T cells can induce dramatic disease regression in patients with leukemia and lymphomas. However, the full potential of this emerging modality is hampered in some cancer settings by a significant rate of therapeutic failure arising from the attenuated engraftment and persistence of CAR-redirected T cells, and tumor relapse following adoptive transfer. Here, we discuss an advanced strategy that facilitates post-infusion in vivo boosting of CAR T cells via CMV vaccination, to mediate durable remission of B cell malignancies by engrafting a CAR molecule onto a CMV-specific T cell. We also discuss a feasible and unique platform for the generation of the CMV-CD19CAR T cells for clinical application. This new approach would overcome multiple challenges in current CAR T cell technology including: short T cell persistence, limited duration of response, and inability to re-stimulate T cells after relapse or persistent disease.