CD8+ T cells are essential for adaptive immunity against infection and tumors. Their ability to proliferate after stimulation is crucial to their functionality. Dendritic cells (DCs) are professional antigen-presenting cells that induce their proliferation. Here, we show that thapsigargin-induced LAD2 mast cell (MC) line-released products can impair the ability of monocyte-derived DCs to induce CD8+ T-cell proliferation and the generation of Th1 cytokine-producing T cells. We found that culture medium conditioned with LAD2 MCs previously stimulated with thapsigargin (thapsLAD2) induces maturation of DCs as determined by the maturation markers CD80, CD83, CD86, and HLA-DR. However, thapsLAD2-matured DCs produced no detectable TNFα or IL-12 during the maturation. In addition, although their surface expression of PD-L1 was comparable with the immature or TLR7/8-agonist (R848)-matured DCs, their TIM-3 expression was significantly higher than in immature DCs and even much higher than in R848-matured DCs. In addition, contrary to R848-matured DCs, the thapsLAD2-matured DCs only tended to induce enhanced proliferation of CD4+ T cells than immature DCs. For CD8+ T cells, this tendency was not even detected because thapsLAD2-matured and immature DCs comparably induced their proliferation, which contrasted with the significantly enhanced proliferation induced by R848-matured DCs. Furthermore, these differences were comparably recapitulated in the ability of the tested DCs to induce IFNγ- and IFNγ/TNFα-producing T cells. These findings show a novel mechanism of MC-mediated regulation of adaptive immune responses.

• MeSH
• aktivace lymfocytů * účinky léků   imunologie   MeSH
• buněčná diferenciace * účinky léků   MeSH
• buněčné linie MeSH
• buněčný receptor 2 viru hepatitidy A metabolismus   MeSH
• CD8-pozitivní T-lymfocyty * imunologie   účinky léků   MeSH
• cytokiny metabolismus   MeSH
• dendritické buňky * imunologie   účinky léků   metabolismus   MeSH
• imidazoly farmakologie   MeSH
• lidé MeSH
• mastocyty * imunologie   účinky léků   metabolismus   MeSH
• monocyty imunologie   účinky léků   metabolismus   MeSH
• proliferace buněk * účinky léků   MeSH
• thapsigargin * farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• buněčný receptor 2 viru hepatitidy A MeSH
• cytokiny MeSH
• HAVCR2 protein, human MeSH Prohlížeč
• imidazoly MeSH
• thapsigargin * MeSH

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
• antigeny CD274 metabolismus   MeSH
• buněčné linie MeSH
• imunoterapie MeSH
• lidé MeSH
• ligandy MeSH
• maligní fibrózní histiocytom * MeSH
• myši nahé MeSH
• myši MeSH
• sarkom * patologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD274 MeSH
• ligandy 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.

• Klíčová slova
• CD8+ T cells, LL-37, cancer, cellular immunotherapy, dendritic cells,
• Publikační typ
• časopisecké články 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.

• Klíčová slova
• COVID-19 vaccination, SARS-CoV-2, cellular immunity, ex vivo expansion, humoral immunity, spike glycoprotein-reactive,
• MeSH
• CD8-pozitivní T-lymfocyty imunologie   MeSH
• COVID-19 * imunologie   MeSH
• glykoprotein S, koronavirus imunologie   MeSH
• glykoproteiny MeSH
• leukocyty mononukleární MeSH
• lidé MeSH
• protilátky virové MeSH
• SARS-CoV-2 MeSH
• vakcína BNT162 MeSH
• vakcíny proti COVID-19 * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• glykoprotein S, koronavirus MeSH
• glykoproteiny MeSH
• protilátky virové MeSH
• spike protein, SARS-CoV-2 MeSH Prohlížeč
• vakcína BNT162 MeSH
• vakcíny proti COVID-19 * MeSH

The preparation of dendritic cells (DCs) for adoptive cellular immunotherapy (ACI) requires the maturation of ex vivo-produced immature(i) DCs. This maturation ensures that the antigen presentation triggers an immune response towards the antigen-expressing cells. Although there is a large number of maturation agents capable of inducing strong DC maturation, there is still only a very limited number of these agents approved for use in the production of DCs for ACI. In seeking novel DC maturation agents, we used differentially activated human mast cell (MC) line LAD2 as a cellular adjuvant to elicit or modulate the maturation of ex vivo-produced monocyte-derived iDCs. We found that co-culture of iDCs with differentially activated LAD2 MCs in serum-containing media significantly modulated polyinosinic:polycytidylic acid (poly I:C)-elicited DC maturation as determined through the surface expression of the maturation markers CD80, CD83, CD86, and human leukocyte antigen(HLA)-DR. Once iDCs were generated in serum-free conditions, they became refractory to the maturation with poly I:C, and the LAD2 MC modulatory potential was minimized. However, the maturation-refractory phenotype of the serum-free generated iDCs was largely overcome by co-culture with thapsigargin-stimulated LAD2 MCs. Our data suggest that differentially stimulated mast cells could be novel and highly potent cellular adjuvants for the maturation of DCs for ACI.

• Klíčová slova
• LAD2 human mast cells, adoptive cellular immunotherapy, dendritic cells, maturation,
• MeSH
• adjuvancia imunologická farmakologie   MeSH
• buněčná diferenciace účinky léků   MeSH
• buněčné kultury metody   MeSH
• dendritické buňky cytologie   účinky léků   imunologie   MeSH
• imunoterapie adoptivní * MeSH
• kokultivační techniky MeSH
• lidé MeSH
• mastocyty cytologie   účinky léků   imunologie   MeSH
• monocyty cytologie   účinky léků   imunologie   MeSH
• prezentace antigenu účinky léků   imunologie   MeSH
• thapsigargin farmakologie   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adjuvancia imunologická MeSH
• thapsigargin MeSH