PURPOSE: Aspartate β-hydroxylase (ASPH) contributes to carcinogenesis by promoting tumor cell proliferation, migration, and invasion. The enzymatic activity of ASPH can be inhibited by small molecule inhibitors that have been shown to have anti-metastatic activity in rodent models. ASPH has also been shown to inhibit the activation of natural killer (NK) cells. Therefore, this study aimed to investigate the effect of ASPH inhibition on the induction of anti-tumor immunity and to analyze the immune cells involved. METHODS: In the mouse TC-1/A9 model characterized by reversible downregulation of major histocompatibility class I (MHC-I) molecules, ASPH inhibition was combined with stimulation of innate and/or adaptive immunity, and the anti-tumor response was analyzed by evaluation of tumor growth, in vivo depletion of immune cell subpopulations, and ELISPOT assay. Characteristics of immune cells in the spleen and tumor were determined by flow cytometry and single-cell RNA sequencing (scRNA-seq). RESULTS: ASPH inhibition did not reduce tumor growth or promote the anti-tumor effect of innate immunity stimulation with the synthetic oligonucleotide ODN1826, but it significantly enhanced tumor growth reduction induced by DNA vaccination. In vivo immune cell depletion suggested that CD8+ T cells played a critical role in this immunity stimulated by combined treatment with ASPH inhibition and DNA vaccination. ASPH inhibition also significantly enhanced the specific response of CD8+ T cells induced by DNA vaccination in splenocytes, as detected by ELISPOT assay, and reduced the number of regulatory T cells in tumors. scRNA-seq confirmed the improved activation of CD8+ T cells in tumor-infiltrating cells after combined therapy with DNA vaccination and ASPH inhibition. It also showed activation of NK cells, macrophages, and dendritic cells in tumors. CONCLUSION: ASPH inhibition stimulated T-cell-mediated adaptive immunity induced by DNA vaccination. Different types of lymphoid and myeloid cells were likely involved in the activated immune response that was efficient against tumors with MHC-I downregulation, which are often resistant to T-cell-based therapies. Due to different types of activated immune cells, ASPH inhibition could improve immunotherapy for tumors with various MHC-I expression levels.

• Klíčová slova
• ASPH, adaptive immunity, cancer immunotherapy, scRNA-seq, tumor microenvironment,
• Publikační typ
• časopisecké články MeSH

Tumor-associated macrophages (TAMs) plentifully infiltrate the tumor microenvironment (TME), but their role in anti-tumor immunity is controversial. Depending on the acquired polarization, they can either support tumor growth or participate in the elimination of neoplastic cells. In this study, we analyzed the TME by RNA-seq and flow cytometry and examined TAMs after ex vivo activation. Tumors with normal and either reversibly or irreversibly decreased expression of major histocompatibility complex class I (MHC-I) molecules were induced with TC-1, TC-1/A9, and TC-1/dB2m cells, respectively. We found that combined immunotherapy (IT), composed of DNA immunization and the CpG oligodeoxynucleotide (ODN) ODN1826, evoked immune reactions in the TME of TC-1- and TC-1/A9-induced tumors, while the TME of TC-1/dB2m tumors was mostly immunologically unresponsive. TAMs infiltrated both tumor types with MHC-I downregulation, but only TAMs from TC-1/A9 tumors acquired the M1 phenotype upon IT and were cytotoxic in in vitro assay. The anti-tumor effect of combined IT was markedly enhanced by a blockade of the colony-stimulating factor-1 receptor (CSF-1R), but only against TC-1/A9 tumors. Overall, TAMs from tumors with irreversible MHC-I downregulation were resistant to the stimulation of cytotoxic activity. These data suggest the dissimilarity of TAMs from different tumor types, which should be considered when utilizing TAMs in cancer IT.

• Klíčová slova
• colony-stimulating factor-1, immunotherapy, macrophages, major histocompatibility complex, repolarization, tumor,
• Publikační typ
• časopisecké články MeSH

Programmed cell death protein 1 (PD-1)/PD-1 ligand 1 (PD-L1) blockade is a promising therapy for various cancer types, but most patients are still resistant. Therefore, a larger number of predictive biomarkers is necessary. In this study, we assessed whether a loss-of-function mutation of the interferon (IFN)-γ receptor 1 (IFNGR1) in tumor cells can interfere with anti-PD-L1 therapy. For this purpose, we used the mouse oncogenic TC-1 cell line expressing PD-L1 and major histocompatibility complex class I (MHC-I) molecules and its TC-1/A9 clone with reversibly downregulated PD-L1 and MHC-I expression. Using the CRISPR/Cas9 system, we generated cells with deactivated IFNGR1 (TC-1/dIfngr1 and TC-1/A9/dIfngr1). In tumors, IFNGR1 deactivation did not lead to PD-L1 or MHC-I reduction on tumor cells. From potential inducers, mainly IFN-α and IFN-β enhanced PD-L1 and MHC-I expression on TC-1/dIfngr1 and TC-1/A9/dIfngr1 cells in vitro. Neutralization of the IFN-α/IFN-β receptor confirmed the effect of these cytokines in vivo. Combined immunotherapy with PD-L1 blockade and DNA vaccination showed that IFNGR1 deactivation did not reduce tumor sensitivity to anti-PD-L1. Thus, the impairment of IFN-γ signaling may not be sufficient for PD-L1 and MHC-I reduction on tumor cells and resistance to PD-L1 blockade, and thus should not be used as a single predictive marker for anti-PD-1/PD-L1 cancer therapy.

• Klíčová slova
• IFN-α, IFN-β, IFNGR1, MHC class I, PD-1/PD-L1, cancer, immune checkpoint therapy,
• MeSH
• antigeny CD274 antagonisté a inhibitory   MeSH
• antigeny CD279 antagonisté a inhibitory   MeSH
• experimentální nádory farmakoterapie   imunologie   metabolismus   patologie   MeSH
• imunoterapie MeSH
• interferon gama antagonisté a inhibitory   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádorové buňky kultivované MeSH
• protinádorové látky imunologicky aktivní farmakologie   MeSH
• transformované buněčné linie účinky léků   imunologie   metabolismus   patologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigeny CD274 MeSH
• antigeny CD279 MeSH
• Cd274 protein, mouse MeSH Prohlížeč
• interferon gama MeSH
• Pdcd1 protein, mouse MeSH Prohlížeč
• protinádorové látky imunologicky aktivní MeSH

Combined immunotherapy constitutes a novel, advanced strategy in cancer treatment. In this study, we investigated immunotherapy in the mouse TC-1/A9 model of human papillomavirus type 16 (HPV16)-associated tumors characterized by major histocompatibility complex class I (MHC-I) downregulation. We found that the induction of a significant anti-tumor response required a combination of DNA vaccination with the administration of an adjuvant, either the synthetic oligodeoxynucleotide ODN1826, carrying immunostimulatory CpG motifs, or α-galactosylceramide (α-GalCer). The most profound anti-tumor effect was achieved when these adjuvants were applied in a mix with a one-week delay relative to DNA immunization. Combined immunotherapy induced tumor infiltration with various subsets of immune cells contributing to tumor regression, of which cluster of differentiation (CD) 8⁺ T cells were the predominant subpopulation. In contrast, the numbers of tumor-associated macrophages (TAMs) were not markedly increased after immunotherapy but in vivo and in vitro results showed that they could be repolarized to an anti-tumor M1 phenotype. A blockade of T cell immunoglobulin and mucin-domain containing-3 (Tim-3) immune checkpoint had a negligible effect on anti-tumor immunity and TAMs repolarization. Our results demonstrate a benefit of combined immunotherapy comprising the activation of both adaptive and innate immunity in the treatment of tumors with reduced MHC-I expression.

• Klíčová slova
• CpG ODN, DNA immunization, MHC-I, cancer immunotherapy, tumor-associated macrophages, α-galactosylceramide,
• MeSH
• adjuvancia imunologická terapeutické užití   MeSH
• CD8-pozitivní T-lymfocyty imunologie   MeSH
• down regulace MeSH
• experimentální nádory terapie   MeSH
• galaktosylceramidy imunologie   MeSH
• imunoterapie metody   MeSH
• makrofágy imunologie   MeSH
• MHC antigeny I. třídy imunologie   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• oligodeoxyribonukleotidy imunologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adjuvancia imunologická MeSH
• galaktosylceramidy MeSH
• MHC antigeny I. třídy MeSH
• oligodeoxyribonukleotidy MeSH

In the recent past, it has repeatedly been reported that CD4 cells play an important role in the immunology of chronic myeloid leukaemia. It was therefore of interest to test their activity in an animal model using bcr-abl-transformed cells. BALB/c mice were four times immunized with a DNA vaccine carrying the bcr-abl fusion gene. Two weeks after the last vaccine dose, the animals were challenged with syngeneic bcr-abl-transformed 12B1 cells which form solid tumors after subcutaneous administration. At the time of challenge, animals were treated with antibodies against the CD8+ T cells or CD4+ T cells. The efficacy of the depletion was monitored and found highly effective. All nonimmunized animals developed tumors. All animals untreated with the antibodies as well as those in which CD8+ T cells had been depleted, were fully protected against the challenge. On the other hand, almost all mice treated with anti-CD4+ antibody developed tumors. These results strongly suggested that the CD4+ T cells acted as effectors in the present system.

• MeSH
• antigeny CD95 imunologie   metabolismus   MeSH
• bcr-abl fúzní proteiny genetika   imunologie   MeSH
• CD4-pozitivní T-lymfocyty imunologie   metabolismus   MeSH
• CD8-pozitivní T-lymfocyty imunologie   metabolismus   MeSH
• DNA vakcíny imunologie   MeSH
• imunizace MeSH
• lidé MeSH
• ligand Fas metabolismus   MeSH
• lymfocytární deplece MeSH
• MHC antigeny II. třídy imunologie   metabolismus   MeSH
• modely nemocí na zvířatech MeSH
• myši MeSH
• nádorová transformace buněk genetika   imunologie   MeSH
• nádory genetika   imunologie   mortalita   prevence a kontrola   MeSH
• protinádorové vakcíny genetika   imunologie   MeSH
• slezina cytologie   imunologie   MeSH
• transformované buněčné linie MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD95 MeSH
• bcr-abl fúzní proteiny MeSH
• DNA vakcíny MeSH
• ligand Fas MeSH
• MHC antigeny II. třídy MeSH
• protinádorové vakcíny MeSH

Viral CC chemokine inhibitor (vCCI) of the clone P13 vaccinia virus (VACV) strain PRAHA lacks eight amino acids in the signal peptide sequence. To study the influence of vCCI on virus biology, a virus with the vCCI gene coding for a prolonged signal sequence was prepared. We found that secreted vCCI attenuated the virus in vivo, and that it correlated with decreased levels of RANTES, eotaxin, TARC, and MDC in the blood in comparison with the parental virus. We determined the influence of vCCI on the CTL response against VACV E3((140-148)) (VGPSNSPTF) and HPV16 E7((49-57)) (RAHYNIVTF) H-2D(b)-restricted epitopes. The examination of the specific CTL response elicited by immunization with the recombinant VACV-expressing tumor-associated HPV16 E7 antigen by IFN-γ ELISPOT showed that the immunogenicity of the recombinant VACV-producing secretory vCCI was similar to that of the parent virus or deletion mutant in the C23L/B29R locus. Immunization with the secretory vCCI-producing recombinant virus has a lower therapeutic anti-tumor effect against TC-1 tumors. Viral CCI downregulated the E7-specific response induced by gene gun immunization with the DNA vaccines pBSC-SigE7 LAMP and pBSC-vCCI. We also observed that the immune response against vCCI elicited by the DNA vaccine did not affect the multiplication of VACV in vivo.

• MeSH
• buněčné linie MeSH
• chemokin CCL17 krev   MeSH
• chemokin CCL5 krev   MeSH
• chemokiny CC antagonisté a inhibitory   krev   MeSH
• cytotoxické T-lymfocyty imunologie   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádorové supresorové proteiny krev   MeSH
• Papillomavirus E7 - proteiny genetika   imunologie   MeSH
• proteiny ADAM krev   MeSH
• protinádorové vakcíny genetika   imunologie   MeSH
• sekvenční delece MeSH
• syntetické vakcíny genetika   imunologie   MeSH
• vakcinace MeSH
• virové proteiny genetika   metabolismus   MeSH
• virové vakcíny imunologie   MeSH
• virus vakcinie genetika   imunologie   patogenita   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ADAM11 protein, human MeSH Prohlížeč
• chemokin CCL17 MeSH
• chemokin CCL5 MeSH
• chemokiny CC MeSH
• nádorové supresorové proteiny MeSH
• oncogene protein E7, Human papillomavirus type 16 MeSH Prohlížeč
• Papillomavirus E7 - proteiny MeSH
• proteiny ADAM MeSH
• protinádorové vakcíny MeSH
• syntetické vakcíny MeSH
• virové proteiny MeSH
• virové vakcíny MeSH

Transient expression of foreign genes based on plant viral vectors is a suitable system for the production of relevant immunogens that can be used for the development of a new generation of vaccines against a variety of infectious diseases. In the present study the epitope derived from HPV-16 L2 minor capsid protein (amino acids 108-120) was expressed from Potato virus X (PVX)-based vector pGR106 as N- or C-terminal fusion with the PVX coat protein (PVX CP) in transgenic Nicotiana benthamiana plants. The fusion protein L2 108-120-PVX CP was successfully expressed in plants at a level of 170 mg/kg of fresh leaf tissue. The C-terminal fusion protein PVX CP- L2 108-120 was expressed using mutated vector sequence to avoid homologous recombination at a level of 8 mg/kg of fresh leaf tissue. Immunogenicity of L2 108-120-PVX CP virus-like particles was tested after immunization of mice by subcutaneous injection or tattoo administration. In animal sera the antibodies against the PVX CP and the L2 108-120 epitope were found after both methods of vaccine delivery.

• MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• ELISA MeSH
• epitopy genetika   metabolismus   MeSH
• genetické vektory genetika   MeSH
• geneticky modifikované rostliny MeSH
• imunizace MeSH
• klonování DNA MeSH
• lidé MeSH
• listy rostlin metabolismus   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• oligonukleotidy genetika   MeSH
• onkogenní proteiny virové metabolismus   MeSH
• protilátky virové krev   MeSH
• rekombinantní fúzní proteiny imunologie   metabolismus   MeSH
• tabák metabolismus   MeSH
• transmisní elektronová mikroskopie MeSH
• virion imunologie   MeSH
• virové plášťové proteiny metabolismus   MeSH
• western blotting MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• coat protein, Potato virus X MeSH Prohlížeč
• epitopy MeSH
• L2 protein, Human papillomavirus type 16 MeSH Prohlížeč
• oligonukleotidy MeSH
• onkogenní proteiny virové MeSH
• protilátky virové MeSH
• rekombinantní fúzní proteiny MeSH
• virové plášťové proteiny MeSH

DNA vaccines showed great promise in preclinical models of infectious and malignant diseases, but their potency was insufficient in clinical trials and is needed to be improved. In this study, we tested systemic administration of two conventional adjuvants, synthetic oligodeoxynucleotide carrying immunostimulatory CpG motifs (CpG-ODN) and levamisole (LMS), and evaluated their effect on immune reactions induced by DNA vaccines delivered by a gene gun. DNA vaccination was directed either against the E7 oncoprotein of human papillomavirus type 16 or against the BCR-ABL1 oncoprotein characteristic for chronic myeloid leukemia. High doses of both adjuvants reduced activation of mouse splenic CD8(+) T lymphocytes, but the overall antitumor effect was enhanced in both tumor models. High-dose CpG-ODN exhibited a superior adjuvant effect in comparison with any combination of CpG-ODN with LMS. In summary, our results demonstrate the benefit of combined therapy with gene-gun-delivered antitumor DNA vaccines and systemic administration of CpG-ODN or LMS.

• MeSH
• adjuvancia imunologická aplikace a dávkování   MeSH
• bcr-abl fúzní proteiny genetika   imunologie   metabolismus   MeSH
• biolistika MeSH
• CD8-pozitivní T-lymfocyty účinky léků   metabolismus   patologie   MeSH
• DNA vakcíny MeSH
• experimentální nádory imunologie   patologie   terapie   MeSH
• imunita účinky léků   MeSH
• levamisol aplikace a dávkování   MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední BALB C MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• oligodeoxyribonukleotidy aplikace a dávkování   MeSH
• Papillomavirus E7 - proteiny genetika   imunologie   metabolismus   MeSH
• protinádorové vakcíny * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adjuvancia imunologická MeSH
• bcr-abl fúzní proteiny MeSH
• CPG-oligonucleotide MeSH Prohlížeč
• DNA vakcíny MeSH
• levamisol MeSH
• oligodeoxyribonukleotidy MeSH
• Papillomavirus E7 - proteiny MeSH
• protinádorové vakcíny * MeSH

BACKGROUND: Vaccinia virus, one of the best known members of poxvirus family, has a wide host range both in vivo and in vitro. The expression of Flt3 ligand (FL) by recombinant vaccinia virus (rVACV) highly influenced properties of the virus in dependence on the level of expression. RESULTS: High production of FL driven by the strong synthetic promoter decreased the growth of rVACV in macrophage cell line J774.G8 in vitro as well as its multiplication in vivo when inoculated in mice. The inhibition of replication in vivo was mirrored in low levels of antibodies against vaccinia virus (anti-VACV) which nearly approached to the negative serum level in non-infected mice. Strong FL expression changed not only the host range of the recombinant but also the basic protein contents of virions. The major proteins - H3L and D8L - which are responsible for the virus binding to the cells, and 28 K protein that serves as a virulence factor, were changed in the membrane portion of P13-E/L-FL viral particles. The core virion fraction contained multiple larger, uncleaved proteins and a higher amount of cellular proteins compared to the control virus. The overexpression of FL also resulted in its incorporation into the viral core of P13-E/L-FL IMV particles. In contrary to the equimolar ratio of glycosylated and nonglycosylated FL forms found in cells transfected with the expression plasmid, the recombinant virus incorporated mainly the smaller, nonglycosylated FL. CONCLUSIONS: It has been shown that the overexpression of the Flt3L gene in VACV results in the attenuation of the virus in vivo.

• MeSH
• buněčné linie MeSH
• exprese genu * MeSH
• lidé MeSH
• membránové proteiny genetika   metabolismus   MeSH
• myši MeSH
• replikace viru MeSH
• vakcínie genetika   metabolismus   virologie   MeSH
• virus vakcinie genetika   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• flt3 ligand protein MeSH Prohlížeč
• membránové proteiny MeSH

Infection with high-risk types of human papillomavirus (HPV) can cause the development of malignant tumors. To study mechanisms responsible for immune escape of tumor cells infected with HPV16, we previously used mouse oncogenic TC-1 cells producing HPV16 E6 and E7 oncoproteins to derive TC-1 clones resistant to immunization against E7. We have found immunoresistance of the clones to correlate with the point mutation in the E7 oncogene, which resulted in the N53S substitution in the immunodominant epitope RAHYNIVTF (aa 49-57). Here, we have shown that this mutation reduced stabilization of H-2D(b) molecules on RMA-S cells and eliminated immunogenicity of E7. The resistance of TC-1 clones was E7-specific as immunization against E6 inhibited tumor growth. Transduction of the TC-1/F9 clone carrying the mutated epitope with the wild-type E7 gene restored susceptibility to immunization against E7. Our results suggest that mutagenesis of tumor antigens can lead to the escape of malignant cells and should be considered in the development and evaluation of cancer immunotherapy.

• MeSH
• antigeny nádorové chemie   MeSH
• bodová mutace MeSH
• epitopy chemie   MeSH
• H-2 antigeny chemie   MeSH
• histokompatibilní antigen H-2D MeSH
• imunodominantní epitopy chemie   MeSH
• imunoterapie metody   MeSH
• lidé MeSH
• mutace MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádory imunologie   metabolismus   terapie   MeSH
• onkogenní proteiny virové chemie   genetika   MeSH
• onkogenní proteiny chemie   MeSH
• Papillomavirus E7 - proteiny MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny nádorové MeSH
• epitopy MeSH
• H-2 antigeny MeSH
• histokompatibilní antigen H-2D MeSH
• imunodominantní epitopy MeSH
• oncogene protein E7, Human papillomavirus type 16 MeSH Prohlížeč
• onkogenní proteiny virové MeSH
• onkogenní proteiny MeSH
• Papillomavirus E7 - proteiny MeSH