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Science Immunology Jun 2024KLRG1 CD8 T cells persist for months after clearance of acute infections and maintain high levels of effector molecules, contributing protective immunity against...
KLRG1 CD8 T cells persist for months after clearance of acute infections and maintain high levels of effector molecules, contributing protective immunity against systemic pathogens. Upon secondary infection, these long-lived effector cells (LLECs) are incapable of forming other circulating KLRG1 memory subsets such as central and effector memory T cells. Thus, KLRG1 memory T cells are frequently referred to as a terminally differentiated population that is relatively short lived. Here, we show that after viral infection of mice, effector cells derived from LLECs rapidly enter nonlymphoid tissues and reduce pathogen burden but are largely dependent on receiving antigen cues from vascular endothelial cells. Single-cell RNA sequencing reveals that secondary memory cells in nonlymphoid tissues arising from either KLRG1 or KLRG1 memory precursors develop a similar resident memory transcriptional signature. Thus, although LLECs cannot differentiate into other circulating memory populations, they still retain the flexibility to enter tissues and establish residency.
Topics: Animals; Receptors, Immunologic; Mice; Lectins, C-Type; Mice, Inbred C57BL; Memory T Cells; Immunologic Memory; CD8-Positive T-Lymphocytes; Female; Mice, Knockout
PubMed: 38941479
DOI: 10.1126/sciimmunol.adj8356 -
Clinical and Experimental Medicine Jun 2024Both atezolizumab (a PD-L1 inhibitor) plus bevacizumab (A+B) and sintilimab (a PD-1 inhibitor) plus bevacizumab (S+B) are recommended as the first-line regimen for... (Comparative Study)
Comparative Study
Both atezolizumab (a PD-L1 inhibitor) plus bevacizumab (A+B) and sintilimab (a PD-1 inhibitor) plus bevacizumab (S+B) are recommended as the first-line regimen for advanced hepatocellular carcinoma (HCC) in China. Different efficacy between the two regimens combined with transvascular intervention for unresectable HCC (uHCC) remain unknown. We retrospectively analyzed uHCC patients treated in three centers by simultaneous combination of A+B or S+B with transarterial chemoembolization (TACE) and FOLFOX-based hepatic arterial infusion chemotherapy (HAIC). Objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and treatment-related adverse events (TRAEs) were compared. Totally 188 patients were included, with 92 and 96 administered A+B+TACE-HAIC (ABTH) and S+B+TACE-HAIC (SBTH), respectively. ORRs (62.0 vs. 70.8%, respectively; P = 0.257) and disease control rates (88.0 vs. 93.8%, P = 0.267) were similar between groups by the mRECIST criteria. ABTH showed no survival advantage over SBTH, with median PFS times of 11.7 months and 13.0 months, respectively (HR = 0.81, 95% CI, 0.52-1.26, P = 0.35) and similar OS times (HR = 1.19, 95% CI, 0.32-4.39, P = 0.8). No significant differences were observed in grade 3-4 TRAEs between groups. Either PD-L1 or PD-1 inhibitor plus bevacizumab combined with TACE-HAIC have similarly excellent therapeutic efficacy with manageable adverse events, representing promising treatment options for uHCC.
Topics: Humans; Carcinoma, Hepatocellular; Male; Bevacizumab; Middle Aged; Female; Liver Neoplasms; Retrospective Studies; Aged; Antineoplastic Combined Chemotherapy Protocols; Adult; Antibodies, Monoclonal, Humanized; Treatment Outcome; Immune Checkpoint Inhibitors; China; Chemoembolization, Therapeutic; Programmed Cell Death 1 Receptor; B7-H1 Antigen; Fluorouracil; Leucovorin
PubMed: 38940944
DOI: 10.1007/s10238-024-01415-y -
European Journal of Nuclear Medicine... Jun 2024The radionuclide pair cerium-134/lanthanum-134 (Ce/La) was recently proposed as a suitable diagnostic counterpart for the therapeutic alpha-emitter actinium-225 (Ac)....
PURPOSE
The radionuclide pair cerium-134/lanthanum-134 (Ce/La) was recently proposed as a suitable diagnostic counterpart for the therapeutic alpha-emitter actinium-225 (Ac). The unique properties of Ce offer perspectives for developing innovative in vivo investigations that are not possible with Ac. In this work, Ac- and Ce-labelled tracers were directly compared using internalizing and slow-internalizing cancer models to evaluate their in vivo comparability, progeny meandering, and potential as a matched theranostic pair for clinical translation. Despite being an excellent chemical match, Ce/La has limitations to the setting of quantitative positron emission tomography imaging.
METHODS
The precursor PSMA-617 and a macropa-based tetrazine-conjugate (mcp-PEG-Tz) were radiolabelled with Ac or Ce and compared in vitro and in vivo using standard (radio)chemical methods. Employing biodistribution studies and positron emission tomography (PET) imaging in athymic nude mice, the radiolabelled PSMA-617 tracers were evaluated in a PC3/PIP (PC3 engineered to express a high level of prostate-specific membrane antigen) prostate cancer mouse model. The Ac and Ce-labelled mcp-PEG-Tz were investigated in a BxPC-3 pancreatic tumour model harnessing the pretargeting strategy based on a trans-cyclooctene-modified 5B1 monoclonal antibody.
RESULTS
In vitro and in vivo studies with both Ac and Ce-labelled tracers led to comparable results, confirming the matching pharmacokinetics of this theranostic pair. However, PET imaging of the Ce-labelled precursors indicated that quantification is highly dependent on tracer internalization due to the redistribution of Ce's PET-compatible daughter La. Consequently, radiotracers based on internalizing vectors like PSMA-617 are suited for this theranostic pair, while slow-internalizing Ac-labelled tracers are not quantitatively represented by Ce PET imaging.
CONCLUSION
When employing slow-internalizing vectors, Ce might not be an ideal match for Ac due to the underestimation of tumour uptake caused by the in vivo redistribution of La. However, this same characteristic makes it possible to estimate the redistribution of Ac's progeny noninvasively. In future studies, this unique PET in vivo generator will further be harnessed to study tracer internalization, trafficking of receptors, and the progression of the tumour microenvironment.
PubMed: 38940841
DOI: 10.1007/s00259-024-06811-w -
Small (Weinheim An Der Bergstrasse,... Jun 2024Adjuvants play a critical role in the induction of effective immune responses by vaccines. Here, a self-assembling nanovaccine platform that integrates adjuvant...
Adjuvants play a critical role in the induction of effective immune responses by vaccines. Here, a self-assembling nanovaccine platform that integrates adjuvant functions into the delivery vehicle is prepared. Cationic Lentinan (CLNT) is mixed with ovalbumin (OVA) to obtain a self-assembling nanovaccine (CLNTO nanovaccine), which induces the uptake and maturation of bone marrow dendritic cells (BMDCs) via the toll-like receptors 2/4 (TLR2/4) to produce effective antigen cross-presentation. CLNTO nanovaccines target lymph nodes (LNs) and induce a robust OVA-specific immune response via TLR and tumor necrosis factor (TNF) signaling pathways, retinoic acid-inducible gene I (RIG-I) receptor, and cytokine-cytokine receptor interactions. In addition, CLNTO nanovaccines are found that promote the activation of follicular helper T (Tfh) cells and induce the differentiation of germinal center (GC) B cells into memory B cells and plasma cells, thereby enhancing the immune response. Vaccination with CLNTO nanovaccine significantly inhibits the growth of ovalbumin (OVA)-expressing B16 melanoma cell (B16-OVA) tumors, indicating its great potential for cancer immunotherapy. Therefore, this study presents a simple, safe, and effective self-assembling nanovaccine that induces helper T cell 1 (Th1) and helper T cell (Th2) immune responses, making it an effective vaccine delivery system.
PubMed: 38940386
DOI: 10.1002/smll.202402792 -
Immunotherapy Jun 2024
PubMed: 38940301
DOI: 10.1080/1750743X.2024.2365622 -
BJU International Jun 2024To assess the association between achievement of prostate-specific antigen (PSA) levels ≤0.2 ng/mL (henceforth 'ultralow') and clinical outcomes in patients in the...
Targeted Investigational Treatment Analysis of Novel Anti-androgen (TITAN) study: ultralow prostate-specific antigen decline with apalutamide plus androgen-deprivation therapy.
OBJECTIVE
To assess the association between achievement of prostate-specific antigen (PSA) levels ≤0.2 ng/mL (henceforth 'ultralow') and clinical outcomes in patients in the 'Targeted Investigational Treatment Analysis of Novel Anti-androgen' (TITAN) study (ClinicalTrials.gov Identifier NCT02489318) with metastatic castration-sensitive prostate cancer (mCSPC).
PATIENTS AND METHODS
Patients in the TITAN study with mCSPC were randomised to 240 mg/day apalutamide (n = 525) or placebo (n = 527) plus androgen-deprivation therapy. This post hoc analysis assessed the achievement of a PSA level of 0.2->0.02 ng/mL ('ultralow one' [UL1]) and ≤0.02 ng/mL ('ultralow two' [UL2]) vs >0.2 ng/mL with apalutamide treatment and its association with radiographic progression-free survival (rPFS), overall survival (OS), time to castration-resistant PC (TTCRPC), and time to PSA progression (TTPP). The landmark analysis and Kaplan-Meier methods were used.
RESULTS
By 3 months, more patients achieved UL1 and UL2 with apalutamide (38% and 23%) vs placebo (15% and 5%). In the apalutamide-treated patients, UL2 vs PSA >0.2 ng/mL at landmark 3 months was associated with significantly longer rPFS (hazard ratio [HR] 0.28, 95% confidence interval [CI] 0.14-0.54), OS (HR 0.24, 95% CI 0.13-0.43), TTCRPC (HR 0.2, 95% CI 0.11-0.38), and TTPP (HR 0.11, 95% CI 0.04-0.27; nominal P values all <0.001); this association was also observed but less pronounced for UL1. Similar findings were observed at 6 months. Early onset of decline to UL2 by 3 months was associated with improved survival vs PSA >0.2 ng/mL anytime (HR 0.12, 95% CI 0.06-0.22; P < 0.001) in apalutamide-treated patients.
CONCLUSIONS
In this post hoc analysis of TITAN, patients with the deepest PSA decline derived the greatest benefit. These results extend our findings of apalutamide efficacy in the overall TITAN population, underscoring the clinical value of PSA kinetics as a marker for treatment efficacy.
PATIENT SUMMARY
Patients with metastatic prostate cancer that is sensitive to ongoing hormonal treatment benefited significantly from the addition of apalutamide compared with placebo. Those who achieved rapid and deep PSA reduction had the greatest survival benefit.
PubMed: 38940282
DOI: 10.1111/bju.16449 -
Molecular Therapy. Oncology Jun 2024Advancing chimeric antigen receptor (CAR)-engineered T cells for the treatment of solid tumors is a major focus in the field of cellular immunotherapy. Several hurdles...
Advancing chimeric antigen receptor (CAR)-engineered T cells for the treatment of solid tumors is a major focus in the field of cellular immunotherapy. Several hurdles have hindered similar CAR T cell clinical responses in solid tumors as seen in hematological malignancies. These challenges include on-target off-tumor toxicities, which have inspired efforts to optimize CARs for improved tumor antigen selectivity and overall safety. We recently developed a CAR T cell therapy targeting prostate stem cell antigen (PSCA) for prostate and pancreatic cancers, showing improved preclinical antitumor activity and T cell persistence by optimizing the intracellular co-stimulatory domain. Similar studies were undertaken to optimize HER2-directed CAR T cells with modifications to the intracellular co-stimulatory domain for selective targeting of breast cancer brain metastasis. In the present study, we evaluate various nonsignaling extracellular spacers in these CARs to further improve tumor antigen selectivity. Our findings suggest that length and structure of the extracellular spacer can dictate the ability of CARs to selectively target tumor cells with high antigen density, while sparing cells with low antigen density. This study contributes to CAR construct design considerations and expands our knowledge of tuning solid tumor CAR T cell therapies for improved safety and efficacy.
PubMed: 38939825
DOI: 10.1016/j.omton.2024.200789 -
IScience Jun 2024Human leukocyte antigen (HLA) class-I molecules present fragments of the cellular proteome to the T cell receptor (TCR) of cytotoxic T cells to control infectious...
Human leukocyte antigen (HLA) class-I molecules present fragments of the cellular proteome to the T cell receptor (TCR) of cytotoxic T cells to control infectious diseases and cancer. The large number of combinations of HLA class-I allotypes and peptides allows for highly specific and dedicated low-affinity interactions to a diverse array of TCRs and natural killer (NK) cell receptors. Whether the divergent HLA class-I peptide complex is exclusive for interactions with these proteins is unknown. Using genome-wide CRISPR-Cas9 activation and knockout screens, we identified peptide-specific HLA-C∗07 combinations that can interact with the surface molecules CD55 and heparan sulfate. These interactions closely resemble the HLA class-I interaction with the TCR regarding both the affinity range and the specificity of the peptide and HLA allele. These findings indicate that various proteins can specifically bind HLA class-I peptide complexes due to their polymorphic nature, which suggests there are more interactions like the ones we describe here.
PubMed: 38939106
DOI: 10.1016/j.isci.2024.110120 -
Molecular Therapy : the Journal of the... Jun 2024Gene editing technologies hold promise for enabling the next generation of adoptive cellular therapies. Conventional gene editing platforms that rely on nuclease...
Gene editing technologies hold promise for enabling the next generation of adoptive cellular therapies. Conventional gene editing platforms that rely on nuclease activity, such as Clustered regularly interspaced short palindromic repeats-CRISPR associated protein 9 (CRISPR-Cas9), allow efficient introduction of genetic modifications; however, these modifications occur via the generation of DNA double-strand breaks (DSBs) and can lead to unwanted genomic alterations and genotoxicity. Here, we apply a novel modular RNA aptamer-mediated Pin-point™ base editing platform to simultaneously introduce multiple gene knockouts and site-specific integration of a transgene in human primary T cells. We demonstrate high editing efficiency and purity at all target sites and significantly reduced frequency of chromosomal translocations compared to the conventional CRISPR-Cas9 system. Site-specific knock-in of a chimeric antigen receptor (CAR) and multiplex gene knockout are achieved within a single intervention and without the requirement for additional sequence-targeting components. The ability to perform complex genome editing efficiently and precisely highlights the potential of the Pin-point platform for application in a range of advanced cell therapies.
PubMed: 38937969
DOI: 10.1016/j.ymthe.2024.06.033 -
Transplant Infectious Disease : An... Jun 2024Hematopoietic stem cell transplant (HSCT) and chimeric antigen receptor T-cell therapy (CAR-T) recipients are at higher risk of serious complications of COVID-19...
BACKGROUND
Hematopoietic stem cell transplant (HSCT) and chimeric antigen receptor T-cell therapy (CAR-T) recipients are at higher risk of serious complications of COVID-19 infection than the general population. Though there is evidence that monoclonal antibodies (MCA) against COVID-19 reduce the risk of death and hospitalization in the general population, data regarding their efficacy in HSCT and CAR-T recipients remains scarce.
METHODS
We conducted a retrospective review of HSCT and CAR-T recipients to compare 30-day outcomes between patients who did and did not receive MCA after their first episode of COVID-19 between May 1, 2020 and December 31, 2022. Outcomes were defined as the most severe complication experienced out of the following: 30-day emergency department visit, hospitalization, intensive care unit admission, and death after COVID-19 infection.
RESULTS
We identified 166 patients comprised of 53.6% allogeneic HSCT, 35.5% autologous HSCT, and 10.8% CAR-T recipients; 107 had received a COVID-19 vaccine >2 weeks prior to testing positive, and 40 were treated with MCA. After adjusting for age, presence of symptoms at the initial positive test, and COVID-19 vaccination status, patients who did not receive MCA were five times more likely to develop complications after COVID-19 infection (adjusted odds ratio 5.0 [95% CI, 1.9-12.8], p = .001).
CONCLUSION
HSCT and CAR-T recipients who received MCA following COVID-19 infection were far less likely to develop COVID-related complications than those who did not receive MCA, regardless of vaccination status. This underscores the potential benefit of developing novel MCA with efficacy against circulating COVID-19 strains.
PubMed: 38937864
DOI: 10.1111/tid.14322