Immunotherapy advances最新文献

Purpose: Despite the proven clinical benefits of cytokine therapy in cancer treatment, systemic administration of cytokines such as IL-12 is constrained by dose-limiting toxicities and short half-lives. To address these challenges, we explored a localized cytokine delivery strategy using engineered neoantigen-reactive T (NRT) cells as carriers in a murine model of osteosarcoma.

Materials and methods: We used a neoantigen from K7M2 osteosarcoma cells to retrovirally transduce NRT cells to express an inducible form of IL-12. We evaluated the engineered NRT cells' antitumor activity and the production of IL-12 and IFN-γ upon in vitro co-culture with tumor cells. We systemically administered NRT-IL-12 cells in a mouse model of osteosarcoma to assess their impact on tumor growth and survival.

Results: In vitro assays demonstrated that the engineered NRT cells exhibited enhanced antitumor activity and produced elevated levels of IL-12 and IFN-γ. In the mouse model of osteosarcoma, systemic administration of NRT-IL-12 cells resulted in a significant reduction in tumor growth and an increase in survival rates compared to the administration of control NRT cells. Further analysis revealed that NRT-IL-12 cells induced a profound increase in CD8+ T-cell infiltration and a decrease in Treg cells within the tumor microenvironment.

Conclusion: Our study presents a novel and efficacious strategy for osteosarcoma immunotherapy by harnessing NRT cells as targeted cytokine delivery vehicles.

Background: During the coronavirus disease 2019 (COVID-19) pandemic, Pfizer/BioNTech BNT162b2, and Moderna mRNA-1273 vaccines were central to the global pandemic control measures.

Methods: Here, we conducted a systematic review and meta-analysis to evaluate their real-world vaccine effectiveness (VE). Our study focussed on those that reported the efficacy of these vaccines against COVID-19 hospitalization. Hospitalization was chosen as the primary outcome as it directly reflects the ability of the vaccine to prevent severe disease. A literature search was undertaken using Medline and Embase on 25 February 2024. From this, 50 studies out of 18,347 articles were included for further analysis.

Results: High VE against hospitalization was reported for both the BNT162b2 and mRNA-1273 COVID-19 vaccines when used either as a primary vaccination series (2-dose) or following an additional booster dose (3-dose). Meta-analysis indicated that the pooled VE estimates for each of these vaccination protocols ranged from 84% to 86%, suggesting strong protectiveness. Our data also imply that booster doses can restore waning effectiveness, with no significant differences observed in VE between the 2-dose and 3-dose protocols. However, subgroup analysis revealed an association between the presence of the Omicron variant and a drop in VE, indicating that future emerging SARS-CoV-2 virus variants could similarly affect VE.

Conclusions: Our review underscores the importance of ongoing research to ensure vaccine strategies remain effective against evolving variants. Our study also identified the need for expanding data collection to include underrepresented populations.

The phosphoinositide-3-kinase (PI3K) pathway function is crucial to the normal development, differentiation, and function of immune cells including B, T, and NK cells. Following the description of two cohorts of patients with an inboirn error of immunity (also known as primary immunodeficiency) with gain-of-function variants in the PIK3CD gene a decade ago, the disease entity activated PI3K delta syndrome (APDS) was named. Since then, many more patients with PIK3CD variants have been described, and loss-of-function variants in PIK3R1 and PTEN have also been linked to APDS. Importantly, the availability of small molecules that inhibit the PI3K pathway has enabled targeted treatment of APDS patients. In this review, we define (i) the PI3K pathway and its role in inborn errors of immunity; (ii) the clinical and immunological presentation of APDS1 (PIK3CD GOF), APDS2 (PIK3R1 LOF), and related disorders; (iii) Diagnostic approaches to identify and functionally validate the genetic causes of disease; (iv) therapeutic interventions to target PI3K hyperactivation; and finally (v) current challenges and future perspectives that require attention for the optimal treatment of patients with APDS and APDS-L diseases.

Background: PRAME (Preferentially expressed Antigen in Melanoma) is a cancer-testis antigen expressed in several tumor indications, representing an attractive anticancer target. However, its intracellular location limits targeting by traditional methods. PRAME peptides are presented on the surface of tumor cells by human leukocyte antigen (HLA) molecules, indicating that a T cell receptor (TCR)-based strategy that redirects T cells to kill PRAME⁺ tumors could be a novel immunotherapeutic option. We confirm that PRAME protein is expressed in cutaneous melanoma, including rare subtypes with limited treatment options, as well as primary and metastatic lung, breast, endometrial, and ovarian tumors. Furthermore, PRAME is expressed homogeneously across tumors with distinct oncogenic mutations, mutation burden, PD-L1 expression, immune infiltration, and features of immune checkpoint resistance. Immunopeptidomic analysis of primary tumors detected HLA class I-restricted PRAME peptides.

Methods: A TCR recognizing PRAME peptide SLLQHLIGL was engineered to high affinity and fused to a CD3 engaging domain to create a TCRxCD3 bispecific molecule (Immune-mobilizing monoclonal TCR Against Cancer, ImmTAC®) with the ability to redirect polyclonal T cells to efficiently kill PRAME⁺ cells.

Rs: The degree of T cell activation was positively correlated with peptide-HLA abundance, with as few as 10 epitopes per cell sufficient for target cell killing. Impaired ImmTAC®-redirected cytotoxicity of exhausted T cells was rescued using an anti-PD-1 antibody, supporting the use of a combination strategy to treat tumors with active PDL1-PD1 axes.

Conclusions: Our data demonstrate selective and efficient T cell activation and killing by a PRAME-directed TCRxCD3 bispecific, supporting further investigation in multiple cancer indications.

Introduction: The clinical efficacy of chimeric antigen and T cell receptor (TCR) T cell immunotherapies is attributed to their ability to proliferate and persist in vivo. Since the interaction of the engineered T cells with the targeted tumour or its environment might suppress their function, their functionality should be characterized not only before but also after adoptive transfer.

Materials and methods: We sought to achieve this by adapting a recently developed Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid whole blood T cell assay to stimulate engineered TCR T cells in small volumes of whole blood (<1 ml) without in vitro cellular purification. As a proof-of-concept, we used this method to longitudinally study two patients with primary Hepatitis B Virus (HBV)-related hepatocellular carcinoma who received multiple dose-escalating infusions of transiently functional mRNA-engineered HBV-TCR T cells.

Results: We demonstrated that a simple pulsing of whole blood with a peptide corresponding to the epitope recognized by the specific HBV-TCR elicited Th1 cytokine secretion in both patients only after HBV-TCR T cell treatment and not before. The amount of cytokines secreted also showed an infusion-dose-dependent association.

Discussions: These findings support the utility of the whole blood cytokine release assay in monitoring the in vivo function and quantity of engineered T cell products following adoptive transfer.

The evolving landscape of cancer immunotherapy has revolutionized cancer treatment. However, the dynamic tumor microenvironment has led to variable clinical outcomes, indicating a need for predictive biomarkers. Noninvasive nuclear imaging, using radiolabeled modalities, has aided in patient selection and monitoring of their treatment response. This approach holds promise for improving diagnostic accuracy, providing a more personalized treatment regimen, and enhancing the clinical response. Nanobodies or single-domain antibodies, derived from camelid heavy-chain antibodies, allow early timepoint detection of targets with high target-to-background ratios. To date, a plethora of nanobodies have been developed for nuclear imaging of tumor-specific antigens, immune checkpoints, and immune cells, both at a preclinical and clinical level. This review comprehensively outlines the recent advancements in nanobody-based nuclear imaging, both on preclinical and clinical levels. Additionally, the impact and expected future advancements on the use of nanobody-based radiopharmaceuticals in supporting cancer diagnosis and treatment follow-up are discussed.

CD8+ T cells contribute to immune responses by producing cytokines when their T-cell receptors (TCRs) recognise peptide antigens on major-histocompability-complex class I. However, excessive cytokine production can be harmful. For example, cytokine release syndrome is a common toxicity observed in treatments that activate T cells, including chimeric antigen receptor (CAR)-T-cell therapy. While the engagement of costimulatory receptors is well known to enhance cytokine production, we have limited knowledge of their ability to regulate the kinetics of cytokine production by CAR-T cells. Here we compare early (0-12 h) and late (12-20 h) production of IFN-gg, IL-2, and TNF-a production by T cells stimulated via TCR or CARs in the presence or absence ligands for CD2, LFA-1, CD28, CD27, and 4-1BB. For T cells expressing TCRs and 1st-generation CARs, activation by antigen alone was sufficient to stimulate early cytokine production, while co-stimulation by CD2 and 4-1BB was required to maintain late cytokine production. In contrast, T cells expressing 2nd-generation CARs, which have intrinsic costimulatory signalling motifs, produce high levels of cytokines in both early and late periods in the absence of costimulatory receptor ligands. Losing the requirement for costimulation for sustained cytokine production may contribute to the effectiveness and/or toxicity of 2nd-generation CAR-T-cell therapy.