Soft tissue sarcomas are aggressive mesenchymal-origin malignancies. Undifferentiated pleomorphic sarcoma (UPS) belongs to the aggressive, high-grade, and least characterized sarcoma subtype, affecting multiple tissues and metastasizing to many organs. The treatment of localized UPS includes surgery in combination with radiation therapy. Metastatic forms are treated with chemotherapy. Immunotherapy is a promising treatment modality for many cancers. However, the development of immunotherapy for UPS is limited due to its heterogeneity, antigenic landscape variation, lower infiltration with immune cells, and a limited number of established patient-derived UPS cell lines for preclinical research. In this study, we established and characterized a novel patient-derived UPS cell line, JBT19. The JBT19 cells express PD-L1 and collagen, a ligand of the immune checkpoint molecule LAIR-1. JBT19 cells can form spheroids in vitro and solid tumors in immunodeficient nude mice. We found JBT19 cells induce expansion of JBT19-reactive autologous and allogeneic NK, T, and NKT-like cells, and the reactivity of the expanded cells was associated with cytotoxic impact on JBT19 cells. The PD-1 and LAIR-1 ligand-expressing JBT19 cells show ex vivo immunogenicity and effective in vivo xenoengraftment properties that can offer a unique resource in the preclinical research developing novel immunotherapeutic interventions in the treatment of UPS.

• MeSH
• B7-H1 Antigen metabolism   MeSH
• Cell Line MeSH
• Immunotherapy MeSH
• Humans MeSH
• Ligands MeSH
• Histiocytoma, Malignant Fibrous * MeSH
• Mice, Nude MeSH
• Mice MeSH
• Sarcoma * pathology   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• B7-H1 Antigen MeSH
• Ligands MeSH

Ex vivo-produced dendritic cells (DCs) constitute the core of active cellular immunotherapy (ACI) for cancer treatment. After many disappointments in clinical trials, the current protocols for their preparation are attempting to boost their therapeutic efficacy by enhancing their functionality towards Th1 response and capability to induce the expansion of cytotoxic tumor-specific CD8+ T cells. LL-37 is an antimicrobial peptide with strong immunomodulatory potential. This potential was previously found to either enhance or suppress the desired anti-tumor DC functionality when used at different phases of their ex vivo production. In this work, we show that LL-37 can be implemented during the whole process of DC production in a way that allows LL-37 to enhance the anti-tumor functionality of produced DCs. We found that the supplementation of LL-37 during the differentiation of monocyte-derived DCs showed only a tendency to enhance their in vitro-induced lymphocyte enrichment with CD8+ T cells. The supplementation of LL-37 also during the process of DC antigen loading (pulsation) and maturation significantly enhanced the cell culture enrichment with CD8+ T cells. Moreover, this enrichment was also associated with the downregulated expression of PD-1 in CD8+ T cells, significantly higher frequency of tumor cell-reactive CD8+ T cells, and superior in vitro cytotoxicity against tumor cells. These data showed that LL-37 implementation into the whole process of the ex vivo production of DCs could significantly boost their anti-tumor performance in ACI.

• Keywords
• CD8+ T cells, LL-37, cancer, cellular immunotherapy, dendritic cells,
• Publication type
• Journal Article MeSH

INTRODUCTION: The COVID-19 vaccine was designed to provide protection against infection by the severe respiratory coronavirus 2 (SARS-CoV-2) and coronavirus disease 2019 (COVID-19). However, the vaccine's efficacy can be compromised in patients with immunodeficiencies or the vaccine-induced immunoprotection suppressed by other comorbidity treatments, such as chemotherapy or immunotherapy. To enhance the protective role of the COVID-19 vaccine, we have investigated a combination of the COVID-19 vaccination with ex vivo enrichment and large-scale expansion of SARS-CoV-2 spike glycoprotein-reactive CD4+ and CD8+ T cells. METHODS: SARS-CoV-2-unexposed donors were vaccinated with two doses of the BNT162b2 SARS-CoV-2 vaccine. The peripheral blood mononuclear cells of the vaccinated donors were cell culture-enriched with T cells reactive to peptides derived from SARS-CoV-2 spike glycoprotein. The enriched cell cultures were large-scale expanded using the rapid expansion protocol (REP) and the peptide-reactive T cells were evaluated. RESULTS: We show that vaccination with the SARS-CoV-2 spike glycoprotein-based mRNA COVID-19 vaccine-induced humoral response against SARS-CoV-2 spike glycoprotein in all tested healthy SARS-CoV-2-unexposed donors. This humoral response was found to correlate with the ability of the donors' PBMCs to become enriched with SARS-CoV-2 spike glycoprotein-reactive CD4+ and CD8+ T cells. Using an 11-day REP, the enriched cell cultures were expanded nearly 1000-fold, and the proportions of the SARS-CoV-2 spike glycoprotein-reactive T cells increased. CONCLUSION: These findings show for the first time that the combination of the COVID-19 vaccination and ex vivo T cell large-scale expansion of SARS-CoV-2-reactive T cells could be a powerful tool for developing T cell-based adoptive cellular immunotherapy of COVID-19.

• Keywords
• COVID-19 vaccination, SARS-CoV-2, cellular immunity, ex vivo expansion, humoral immunity, spike glycoprotein-reactive,
• MeSH
• CD8-Positive T-Lymphocytes immunology   MeSH
• COVID-19 * immunology   MeSH
• Spike Glycoprotein, Coronavirus immunology   MeSH
• Glycoproteins MeSH
• Leukocytes, Mononuclear MeSH
• Humans MeSH
• Antibodies, Viral MeSH
• SARS-CoV-2 MeSH
• BNT162 Vaccine MeSH
• COVID-19 Vaccines * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Spike Glycoprotein, Coronavirus MeSH
• Glycoproteins MeSH
• Antibodies, Viral MeSH
• spike protein, SARS-CoV-2 MeSH Browser
• BNT162 Vaccine MeSH
• COVID-19 Vaccines * MeSH

The adaptive immune response to severe acute respiratory coronavirus 2 (SARS-CoV-2) is important for vaccine development and in the recovery from coronavirus disease 2019 (COVID-19). Men and cancer patients have been reported to be at higher risks of contracting the virus and developing the more severe forms of COVID-19. Prostate cancer (PCa) may be associated with both of these risks. We show that CD4+ T cells of SARS-CoV-2-unexposed patients with hormone-refractory (HR) metastatic PCa had decreased CD4+ T cell immune responses to antigens from SARS-CoV-2 spike glycoprotein but not from the spiked glycoprotein of the 'common cold'-associated human coronavirus 229E (HCoV-229E) as compared with healthy male volunteers who responded comparably to both HCoV-229E- and SARS-CoV-2-derived antigens. Moreover, the HCoV-229E spike glycoprotein antigen-elicited CD4+ T cell immune responses cross-reacted with the SARS-CoV-2 spiked glycoprotein antigens. PCa patients may have impaired responses to the vaccination, and the cross-reactivity can mediate antibody-dependent enhancement (ADE) of COVID-19. These findings highlight the potential for increased vulnerability of PCa patients to COVID-19.

• Keywords
• COVID-19, HCoV-229E, SARS-CoV-2, prostate cancer, spike glycoprotein,
• MeSH
• Adaptive Immunity MeSH
• CD4-Positive T-Lymphocytes immunology   MeSH
• CD8-Positive T-Lymphocytes immunology   MeSH
• COVID-19 immunology   virology   MeSH
• Cytokines immunology   MeSH
• Spike Glycoprotein, Coronavirus immunology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Coronavirus 229E, Human immunology   MeSH
• Prostatic Neoplasms immunology   pathology   MeSH
• SARS-CoV-2 immunology   MeSH
• Aged MeSH
• Cross Reactions MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Cytokines MeSH
• Spike Glycoprotein, Coronavirus MeSH
• spike protein, SARS-CoV-2 MeSH Browser

CD8+ T cells protect against tumors and intracellular pathogens. The inflammatory cytokines IL-2, IL-15, and IL-7 are necessary for their expansion. However, elevated serum levels of these cytokines are often associated with cancer, poorer prognosis of cancer patients, and exhaustion of antigen-expanded CD8+ T cells. The impact of acute conditioning of antigen-expanded CD8+ T cells with these cytokines is unknown. Here, we generated antigen-expanded CD8+ T cells using dendritic cells and PC-3 cells. The cells were acutely (18-24 h) conditioned with IL-2 and either the GSK3β inhibitor TWS119, the mTORC1 inhibitor rapamycin, or the mTORC1/2 inhibitor Torin1, then their immediate and post-re-expansion (distal) cytokine responses after antigen rechallenge were evaluated. We found that acute IL-2 conditioning upregulated the immediate antigen-induced cytokine response of the tested cells. Following their re-expansion, however, the cells showed a decreased cytokine response. These IL-2 conditioning-mediated impacts were counteracted with TWS119 or rapamycin but not with Torin1. Our data revealed that the acute conditioning of antigen-expanded CD8+ T cells with IL-2 modulates the GSK3β-mTORC signaling axis. This modulation differentially affected the immediate and distal cytokine responses of the cells. The acute targeting of this signaling axis could, therefore, represent a novel strategy for the modulation of antigen-expanded CD8+ T cells.

• Keywords
• CD8+ T cells, GSK-3β, TWS119, Tim-3, Torin1, antigen rechallenge, cytokine starvation, mTOR, rapamycin,
• Publication type
• Journal Article MeSH

In a limited number of human malignancies, anti-CD47 therapy leads to the rapid clearance of tumor cells by macrophages. In esophageal squamous cell carcinoma, anti-CD47 treatment has shown promising results in vitro. However, the CD47 expression pattern in tumor-infiltrating lymphocytes (TILs), which are associated with prolonged overall survival and serve as a positive prognostic factor, is largely unknown. In this study, a total of 36 tissue samples from the tumor, peritumoral tissue, and adjacent healthy esophageal tissue was obtained from 12 esophageal carcinoma (EC) patients, and the surface expression of CD47 was evaluated in natural killer (NK) cells, CD8+ T cells, and the nonlymphocyte cell fraction. We found that the proportions of the evaluated cells and their CD47-expressing populations were comparable across the analyzed tissue compartments. However, the proportions of CD47-expressing populations in the analyzed tissue compartments were significantly higher in NK cells and CD8+ T cells than in the nonlymphocyte cell fraction. Importantly, the intensity of CD47 staining was also significantly higher in the tested immune cells than in the nonlymphocyte cell fraction. High expression of CD47 in tissue-infiltrating NK cells and CD8+ T cells in EC patients can, therefore, affect the efficacy of anti-CD47 therapy in EC.

• MeSH
• CD47 Antigen genetics   metabolism   MeSH
• Killer Cells, Natural metabolism   MeSH
• CD8-Positive T-Lymphocytes metabolism   MeSH
• Carcinoma metabolism   MeSH
• Middle Aged MeSH
• Humans MeSH
• Esophageal Neoplasms immunology   metabolism   MeSH
• Gene Expression Regulation, Neoplastic genetics   MeSH
• Aged MeSH
• Esophageal Squamous Cell Carcinoma MeSH
• Lymphocytes, Tumor-Infiltrating immunology   MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• CD47 Antigen MeSH
• CD47 protein, human MeSH Browser