Personalized neoantigen-based T cell therapy triggers cytotoxic lymphocytes expressing polyclonal TCR against metastatic ovarian cancer.

Neoantigen-reactive cytotoxic T lymphocytes play a vital role in precise cancer cell elimination. In this study, we demonstrate the effectiveness of personalized neoantigen-based T cell therapy in inducing tumor regression in two patients suffering from heavily-burdened metastatic ovarian cancer. Our approach involved the development of a robust pipeline for ex vivo expansion of neoantigen-reactive T lymphocytes. Neoantigen peptides were designed and synthesized based on the somatic mutations of the tumors and their predicted HLA binding affinities. These peptides were then presented to T lymphocytes through co-culture with neoantigen-loaded dendritic cells for ex vivo expansion. Subsequent to cell therapy, both patients exhibited significant reductions in tumor marker levels and experienced substantial tumor regression. One patient achieved repeated cancer regression through infusions of T cell products generated from newly identified neoantigens. Transcriptomic analyses revealed a remarkable increase in neoantigen-reactive cytotoxic lymphocytes in the peripheral blood of the patients following cell therapy. These cytotoxic T lymphocytes expressed polyclonal T cell receptors (TCR) against neoantigens, along with abundant cytotoxic proteins and pro-inflammatory cytokines. The efficacy of neoantigen targeting was significantly associated with the immunogenicity and TCR polyclonality. Notably, the neoantigen-specific TCR clonotypes persisted in the peripheral blood after cell therapy. Our findings indicate that personalized neoantigen-based T cell therapy triggers cytotoxic lymphocytes expressing polyclonal TCR against ovarian cancer, suggesting its promising potential in cancer immunotherapy.

Therapeutic Vaccines Targeting Neoantigens to Induce T-Cell Immunity against Cancers.

Cancer immunotherapy has achieved multiple clinical benefits and has become an indispensable component of cancer treatment. Targeting tumor-specific antigens, also known as neoantigens, plays a crucial role in cancer immunotherapy. T cells of adaptive immunity that recognize neoantigens, but do not induce unwanted off-target effects, have demonstrated high efficacy and low side effects in cancer immunotherapy. Tumor neoantigens derived from accumulated genetic instability can be characterized using emerging technologies, such as high-throughput sequencing, bioinformatics, predictive algorithms, mass-spectrometry analyses, and immunogenicity validation. Neoepitopes with a higher affinity for major histocompatibility complexes can be identified and further applied to the field of cancer vaccines. Therapeutic vaccines composed of tumor lysates or cells and DNA, mRNA, or peptides of neoantigens have revoked adaptive immunity to kill cancer cells in clinical trials. Broad clinical applicability of these therapeutic cancer vaccines has emerged. In this review, we discuss recent progress in neoantigen identification and applications for cancer vaccines and the results of ongoing trials.

Rhein, An Anthraquinone Drug, Suppresses the NLRP3 Inflammasome and Macrophage Activation in Urate Crystal-Induced Gouty Inflammation.

Rhein, an anthraquinone drug, is a widely used traditional Chinese medicine. Rhein is a major bioactive metabolite of diacerein which has been approved for treating osteoarthritis with a good safety profile in humans. Gouty arthritis is an inflammatory disease characterized by urate crystal-induced NLRP3 inflammasome activation with up-regulated caspase-1 protease and IL-1 ß in macrophages. Inhibition of the NLRP3 inflammasome formation has been considered as a potential therapeutic avenue for treating or preventing many inflammatory diseases. This study aimed to evaluate the anti-inflammatory effects of rhein on gouty arthritis. Rhein within the physiological levels of humans showed no toxicity on the cell viability and differentiation, but significantly decreased the production of IL-1 ß , TNF- α and caspase-1 protease in urate crystal-activated macrophages. Compared to medium controls, rhein at the therapeutic concentration (2.5 µ g/mL) effectively inhibited IL-1 ß production by 47% ( P=0.002 ). Rhein did not affect the mRNA levels of CASP1, NLRP3 and ASC, but suppressed the protein expression and enzyme activity of caspase-1. Immunofluorescence confocal microscopy further revealed that rhein suppressed the aggregation of ASC speck and inhibited the formation of NLRP3 inflammasome. Rhein of 5 µ g/mL significantly decreased the ASC speck to 36% ( P=0.0011 ), and reduced the NLRP3 aggregates to 37.5% ( P=0.014 ). Our data demonstrate that rhein possesses pharmacological activity to suppress caspase-1 protease activity and IL-1 ß production by interfering with the formation of NLRP3 multiprotein complex. These results suggest that rhein has therapeutic potential for treating NLRP3 inflammasome-mediated diseases such as gouty arthritis.

Recent Development and Clinical Application of Cancer Vaccine: Targeting Neoantigens.

Recently, increasing data show that immunotherapy could be a powerful weapon against cancers. Comparing to the traditional surgery, chemotherapy or radiotherapy, immunotherapy more specifically targets cancer cells, giving rise to the opportunities to the patients to have higher response rates and better quality of life and even to cure the disease. Cancer vaccines could be designed to target tumor-associated antigens (TAAs), cancer germline antigens, virus-associated antigens, or tumor-specific antigens (TSAs), which are also called neoantigens. The cancer vaccines could be cell-based (e.g., dendritic cell vaccine provenge (sipuleucel-T) targeting prostatic acid phosphatase for metastatic prostate cancer), peptide/protein-based, or gene- (DNA/RNA) based, with the different kinds of adjuvants. Neoantigens are tumor-specific and could be presented by MHC molecules and recognized by T lymphocytes, serving the ideal immune targets to increase the therapeutic specificity and decrease the risk of nonspecific autoimmunity. By targeting the shared antigens and private epitopes, the cancer vaccine has potential to treat the disease. Accordingly, personalized neoantigen-based immunotherapies are emerging. In this article, we review the literature and evidence of the advantage and application of cancer vaccine. We summarize the recent clinical trials of neoantigen cancer vaccines which were designed according to the patients' personal mutanome. With the rapid development of personalized immunotherapy, it is believed that tumors could be efficiently controlled and become curable in the new era of precision medicine.

Oxypurinol-Specific T Cells Possess Preferential TCR Clonotypes and Express Granulysin in Allopurinol-Induced Severe Cutaneous Adverse Reactions.

Allopurinol, a first-line drug for treating gout and hyperuricemia, is one of the leading causes of severe cutaneous adverse reactions (SCARs). To investigate the molecular mechanism of allopurinol-induced SCAR, we enrolled 21 patients (13 Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) and 8 drug reaction with eosinophilia and systemic symptoms (DRESS)), 11 tolerant controls, and 23 healthy donors. We performed in vitro T-cell activation assays by culturing peripheral blood mononuclear cells (PBMCs) with allopurinol, oxypurinol, or febuxostat and measuring the expression of granulysin and IFN-γ in the supernatants of cultures. TCR repertoire was investigated by next-generation sequencing. Oxypurinol stimulation resulted in a significant increase in granulysin in the cultures of blood samples from SCAR patients (n=14) but not tolerant controls (n=11) or healthy donors (n=23). Oxypurinol induced T-cell response in a concentration- and time-dependent manner, whereas allopurinol or febuxostat did not. T cells from patients with allopurinol-SCAR showed no crossreactivity with febuxostat. Preferential TCR-V-ß usage and clonal expansion of specific CDR3 (third complementarity-determining region) were found in the blister cells from skin lesions (n=8) and oxypurinol-activated T-cell cultures (n=4) from patients with allopurinol-SCAR. These data suggest that, in addition to HLA-B*58:01, clonotype-specific T cells expressing granulysin upon oxypurinol induction participate in the pathogenesis of allopurinol-induced SCAR.