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Chimeric antigen receptor (CAR) T cell therapy has emerged as a promising modality for anti-cancer treatment. Its efficacy is quite remarkable in hematological tumors. Owing to their excellent clinical results, gene- modified cell therapies, including T cells, natural killer (NK) cells, and macrophages, are being actively studied in both academia and industry. However, the protocol to make CAR immune cells is too complicated, so it is still unclear how to efficiently produce the potent CAR immune cells. To manufacture effective CAR immune cells, we need to be aware of not only how to obtain highly infective viral particles, but also how to transduce CAR genes into immune cells. In this paper, we provide detailed information on spinoculation, which is one of the best known protocols to transduce genes into immune cells, in a methodological view. Our data indicate that gene transduction is significantly dependent on speed and duration of centrifugation, concentration and number of viral particles, the concentration of polybrene, and number of infected immune cells. In addition, we investigated on the optimal polyethylene glycol (PEG) solution to concentrate the viral supernatant and the optimized DNA ratios transfected into 293T cells to produce high titer of viral particles. This study provides useful information for practical production of the gene-modified immune cells using viral vectors. [ABSTRACT FROM AUTHOR]

Treatment failure or relapse due to tumor escape caused by reduction in target antigen expression has become a challenge in the field of CART therapy. Target antigen density is closely related to the effectiveness of CART therapy, and reduced or lost target antigen expression limits the efficacy of CART therapy and hinders the durability of CAR T cells. Epigenetic drugs can regulate histones for molecular modifications to regulate the transcriptional, translational and post-translational modification processes of target agents, and we demonstrated for the first time the role in regulating CD22 expression and its effect on the efficacy of CD22 CART. In this paper, we found that Chidamide promoted the expression of CD22 on the surface of B-cell tumor cells in vitro and in vivo, and enhanced the function of CD22 CART. As for mechanisms, we demonstrated that Chidamide did not affect CD22 mRNA transcription, but significantly increased the expression of total CD22 protein, indicating that Chidamide may upregulate cell surface CD22 expression by affecting the distribution of CD22 protein. In summary, our results suggest that Chidamide may enhance the efficacy of CD22 CART by inhibiting histone deacetylases to regulate post-transcriptional modifications that affect protein distribution to increase the expression of CD22 on the cell surface. [ABSTRACT FROM AUTHOR]

The rapid expansion of cancer immunology and immunotherapy builds upon the success of early immune checkpoint inhibitors (ICI) and chimeric antigen receptor T cells for some cancer types. Many gaps still exist, however, in the scientific knowledge of immune dysfunction in the tumour microenvironment and predicting clinical immunotherapy response to allow more cancer patients to benefit from immunotherapy. The Cancer Immunotherapy Collection within Scientific Reports describes pioneering preclinical and clinical studies addressing these concepts, representing significant insights and breakthroughs in the field. [ABSTRACT FROM AUTHOR]

Success of immunotherapeutic approaches using genetically engineered antibodies and T cells modified with chimeric antigen receptors (CARs) depends, among other things, on the selection of antigen binding domains with desirable expression and binding characteristics. We developed a luciferase-based assay, termed Malibu-Glo Assay, which streamlines the process of optimization of an antigen binding domain with desirable properties and allows the sensitive detection of tumor antigens. The assay involves a recombinant immunoconjugate, termed Malibu-Glo reagent, comprising an immunoglobulin or a non-immunoglobulin based antigen binding domain genetically linked to a marine luciferase. Malibu-Glo reagent can be conveniently produced in mammalian cells as a secreted protein that retains the functional activity of both the antigen binding domain and the luciferase. Moreover, crude supernatant containing the secreted Malibu-Glo reagent can directly be used for detection of cell surface antigens obviating the laborious steps of protein purification and labeling. We further demonstrate the utility of Malibu-Glo assay for the selection of optimal single chain fragment variables (scFvs) with desired affinity characteristics for incorporation into CARs. In summary, Malibu-Glo assay is a fast, simple, sensitive, specific and economical assay for antigen detection with multiple applications in the fields of antibody engineering, antibody humanization and CAR-T cell therapy. [ABSTRACT FROM AUTHOR]

The development of chimeric antigen receptor (CAR) and bispecific T-cell engager (BiTE) has led to the successful application of cancer immunotherapy. The potential reactivity mediated by CAR- and BiTE-redirected T cells needs to be assessed to facilitate the application of these treatment options to a broader range of patients. Here, we have generated CAR and BiTE possessing the same single chain fragment variable (scFv) specific for the HLA-A2/NY-ESO-1157-165 complex (A2/NY-ESO-1157). Using HLA-A2+NY-ESO-1+ myeloma cells and peptides presented by HLA-A2 molecules as a model, both sets of redirected T cells recognized and killed HLA-A2+NY-ESO-1+ myeloma cells in an A2/NY-ESO-1157-specific manner in vitro. Moreover, CAR- and BiTE-activated T cells showed similar functional avidity, as assessed by cytokine production and killing activity, both displaying antitumor reactivity against HLA-A2+NY-ESO-1+ myeloma cells in vivo. Interestingly, cross-reactivity for homologous peptides presented by HLA-A*02:01 and NY-ESO-1157 peptide presented by HLA-A2 alleles was not identical between CAR- and BiTE-redirected T cells, probably due to structural differences of modified antibodies. These results have demonstrated that both antitumor CAR- and BiTE-activated T cells have comparable potential to recognize tumors, while paying attention to unknown off-target reactivity that would differ for each antibody-based modality even if the same scFv was employed. [ABSTRACT FROM AUTHOR]