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1.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35563292

RESUMO

During the sustained COVID-19 pandemic, global mass vaccination to achieve herd immunity can prevent further viral spread and mutation. A protein subunit vaccine that is safe, effective, stable, has few storage restrictions, and involves a liable manufacturing process would be advantageous to distribute around the world. Here, we designed and produced a recombinant spike (S)-Trimer that is maintained in a prefusion state and exhibits a high ACE2 binding affinity. Rodents received different doses of S-Trimer (0.5, 5, or 20 µg) antigen formulated with aluminum hydroxide (Alum) or an emulsion-type adjuvant (SWE), or no adjuvant. After two vaccinations, the antibody response, T-cell responses, and number of follicular helper T-cells (Tfh) or germinal center (GC) B cells were assessed in mice; the protective efficacy was evaluated on a Syrian hamster infection model. The mouse studies demonstrated that adjuvating the S-Trimer with SWE induced a potent humoral immune response and Th1-biased cellular immune responses (in low dose) that were superior to those induced by Alum. In the Syrian hamster studies, when S-Trimer was adjuvanted with SWE, higher levels of neutralizing antibodies were induced against live SARS-CoV-2 from the original lineage and against the emergence of variants (Beta or Delta) with a slightly decreased potency. In addition, the SWE adjuvant demonstrated a dose-sparing effect; thus, a lower dose of S-Trimer as an antigen (0.5 µg) can induce comparable antisera and provide complete protection from viral infection. These data support the utility of SWE as an adjuvant to enhance the immunogenicity of the S-Trimer vaccine, which is feasible for further clinical testing.

2.
Arch Toxicol ; 2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35396937

RESUMO

Mesothelin (MSLN) is a cell surface protein associated with tumor invasion and metastasis. This study aims to explore the biological function of MSLN in gastric cancer and to evaluate the association of MSLN polymorphism (rs3764247, rs3764246, rs12597489, rs1057147, rs3765319) with the risk and prognosis of gastric cancer. Small interfering RNA (siRNA) transfection and MSLN overexpression were performed in human gastric cancer cell lines, respectively. The proliferation of tumor cells was evaluated by Cell counting kit 8(CCK-8) and colony formation assay. Wound healing assay and transwell assay were used to elucidate gastric cancer cell migration and invasion rates. We conducted a case-control study involving 860 patients with gastric cancer and 870 controls. All mutation sites were genotyped by PCR-LDR sequencing. First, our study revealed the cancer-promoting role of MSLN in gastric cancer. Second, we also demonstrated that rs3764247 and rs3764246 were associated with a reduced risk of gastric cancer (OR = 0.83, p = 0.010; OR = 0.84, p = 0.011; respectively). The clinicopathological analysis further showed that rs3764247 was closely related to T stage, vascular infiltration, and HER2 expression. In addition, in the survival analysis of 392 patients with gastric cancer, patients with rs3764247 CC genotype had poorer survival than patients with AA + AC genotype after adjusting for age, sex, TNM stage, and Lauren classification (HR = 2.07, p = 0.029). Our findings indicated that MSLN could be an oncogene whose polymorphisms were closely related to the risk and prognosis of gastric cancer.

3.
Pathol Res Pract ; 233: 153850, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35367937

RESUMO

BACKGROUND: The most studied genetic polymorphisms associated with gastric cancer (GC) risk are located in protein-coding genes. However, the localization of these in long non-coding RNAs (lncRNAs) has not been fully studied. We aim to investigate the associations of Long non-coding RNA macrophage migration inhibitory factor antisense RNA1(Lnc-MIF-AS1) five polymorphisms (rs755622, rs17004044, rs2070767, rs1007889, rs2000468) with the risk and prognosis of GC. METHODS: A total of 844 GC patients and 871 controls were included in the study. Genotyping was carried out using polymerase chain reaction-ligase detection reaction (PCR-LDR) technology. Odds ratios (ORs) and 95% confidence intervals (CIs) generated from unconditional logistic regression, were applied to quantify the effects of MIF-AS1 gene SNPs on GC risk. Log-rank test and Cox regression analysis were fitted to estimate hazard ratios (HRs) to quantify the effects of MIF-AS1 gene SNPs on GC prognosis. RESULTS: Significant associations were identified between MIF-AS1 rs17004044 variants and GC group in the codominant, dominant and additive models (OR = 2.843, P = 0.010; OR = 1.370, P = 0.004; and OR = 1.386; P = 0.001). In addition, association between rs17004044 variants and survival of GC was extremely observed (TC HR = 2.02 (1.21-3.37) P = 0.007, CC HR = 5.61 (2.12-14.83), P = 0.001). CONCLUSION: MIF-AS1 polymorphism rs17004044 contributes to increased predisposition and prognosis to GC.


Assuntos
Fatores Inibidores da Migração de Macrófagos , RNA Longo não Codificante , Neoplasias Gástricas , Humanos , Oxirredutases Intramoleculares/genética , Fatores Inibidores da Migração de Macrófagos/genética , Polimorfismo de Nucleotídeo Único/genética , Prognóstico , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética
4.
J Chem Theory Comput ; 18(4): 2737-2748, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35244397

RESUMO

Three-dimensional atomic-level models of polymers are the starting points for physics-based simulation studies. A capability to generate reasonable initial structural models is highly desired for this purpose. We have developed a python toolkit, namely, polymer structure predictor (psp), to generate a hierarchy of polymer models, ranging from oligomers to infinite chains to crystals to amorphous models, using a simplified molecular-input line-entry system (SMILES) string of the polymer repeat unit as the primary input. This toolkit allows users to tune several parameters to manage the quality and scale of models and computational cost. The output structures and accompanying force field (GAFF2/OPLS-AA) parameter files can be used for downstream ab initio and molecular dynamics simulations. The psp package includes a Colab notebook where users can go through several examples, building their own models, visualizing them, and downloading them for later use. The psp toolkit, being a first of its kind, will facilitate automation in polymer property prediction and design.


Assuntos
Simulação de Dinâmica Molecular , Polímeros , Modelos Estruturais , Polímeros/química
5.
Cell Death Discov ; 8(1): 20, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35017465

RESUMO

Gastric cancer (GC) is a global health problem and further studies of its molecular mechanisms are needed to identify effective therapeutic targets. Although some long noncoding RNAs (lncRNAs) have been found to be involved in the progression of GC, the molecular mechanisms of many GC-related lncRNAs remain unclear. In this study, a series of in vivo and in vitro assays were performed to study the relationship between FAM225A and GC, which showed that FAM225A levels were correlated with poor prognosis in GC. Higher FAM225A expression tended to be correlated with a more profound lymphatic metastasis rate, larger tumor size, and more advanced tumor stage. FAM225A also promoted gastric cell proliferation, invasion, and migration. Further mechanistic investigation showed that FAM225A acted as a miR-326 sponge to upregulate its direct target PADI2 in GC. Overall, our findings indicated that FAM225A promoted GC development and progression via a competitive endogenous RNA network of FAM225A/miR-326/PADI2 in GC, providing insight into possible therapeutic targets and prognosis of GC.

6.
J Immunother Cancer ; 9(10)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34599024

RESUMO

BACKGROUND: The major challenge of antitumor immunotherapy is dealing with the immunosuppressive tumor microenvironment, which involves immature myeloid cell accumulation that results in T cell dysfunction. Myeloid cell activation is induced by Toll-like receptor agonists. Additionally, granulocyte/macrophage colony stimulating factor (GM-CSF) promotes myelopoiesis and recruits myeloid cells. Here, we combined the Toll-like receptor 2 (TLR2) agonist lipoprotein and GM-CSF to assess whether this bifunctional immunotherapy has synergistic effects on myeloid cells and could be further developed as a therapeutic intervention that enhances the antitumor response. METHODS: We investigated the synergistic effects of biadjuvanted tumor antigen on antigen-presenting cell (APC) activation in bone marrow-derived dendritic cells. Furthermore, therapeutic efficacy was monitored in different tumor models treated via intratumoral or subcutaneous administration routes. The immune effects of the bifunctional fusion protein on myeloid cells in the tumor mass and draining lymph nodes were analyzed by flow cytometry. The induction of cytotoxic T lymphocytes was evaluated via intracellular cytokine levels, perforin/granzyme B staining and an in vivo killing assay. RESULTS: The TLR2 agonist lipoprotein combined with GM-CSF synergistically induced DC maturation, which subsequently enhanced antitumor immunity. In addition, rlipoE7m-MoGM modulated tumor-infiltrating myeloid cell populations. Vaccination with rlipoE7m-MoGM therapy increased the number of CCR7+CD103+ cDC1s, whereas the number of suppressive tumor-associated macrophages was reduced in the tumor lesions. Consistent with this observation, proliferating antigen-specific CD8+ T cells are highly infiltrated within the tumor, and the expression of IFN-r and perforin was most pronounced within antigen-specific CD8+ T cells in mice administered rlipoE7m-MoGM therapy. This finding corresponded with observation that the combination of a TLR2 agonist and GM-CSF provides increased antitumor activity by inhibiting established tumor outgrowth and protecting against metastatic cancer compared with a TLR2 agonist alone. Importantly, tumor growth inhibition was not due to the direct effects of the TLR2 agonist or GM-CSF but was instead due to the induction of antigen-specific immunity. CONCLUSIONS: The combination of a TLR2 agonist and GM-CSF has synergistic effects that inhibit tumor growth and modulate tumor-infiltrating APCs. This therapeutic approach could be applied to other tumor antigens to treat different cancers.


Assuntos
Antígenos de Neoplasias/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Receptor 2 Toll-Like/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Microambiente Tumoral
7.
Int J Pharm ; 607: 121024, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34416331

RESUMO

Vaccination is regarded as the most effective intervention for controlling the coronavirus disease 2019 (COVID-19) pandemic. The objective of this study is to provide comprehensive information on lipid squalene nanoparticle (SQ@NP)-adjuvanted COVID-19 vaccines regarding modulating immune response and enhancing vaccine efficacy. After being adjuvanted with SQ@NP, the SARS-CoV-2 spike (S) subunit protein was intramuscularly (i.m.) administered to mice. Serum samples investigated by ELISA and virus neutralizing assay showed that a single-dose SQ@NP-adjuvanted S-protein vaccine can induce antigen-specific IgG and protective antibodies comparable with those induced by two doses of nonadjuvanted protein vaccine. When the mice received a boosting vaccine injection, anamnestic response was observed in the groups of adjuvanted vaccine. Furthermore, the secretion of cytokines in splenocytes, such as interferon (IFN)-γ, interleukin (IL)-5 and IL-10, was significantly enhanced after adjuvantation of S-protein vaccine with SQ@NP; however, this was not the case for the vaccine adjuvanted with conventional aluminum mineral salts. Histological examination of injection sites showed that the SQ@NP-adjuvanted vaccine was considerably well tolerated following i.m. injection in mice. These results pave the way for the performance tuning of optimal vaccine formulations against COVID-19.


Assuntos
COVID-19 , Nanopartículas , Adjuvantes Imunológicos , Animais , Anticorpos Antivirais , Vacinas contra COVID-19 , Humanos , Lipídeos , Camundongos , SARS-CoV-2 , Esqualeno
8.
PLoS Negl Trop Dis ; 15(5): e0009374, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34043618

RESUMO

The development of efficient vaccines against COVID-19 is an emergent need for global public health. The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a major target for the COVID-19 vaccine. To quickly respond to the outbreak of the SARS-CoV-2 pandemic, a nucleic acid-based vaccine is a novel option, beyond the traditional inactivated virus vaccine or recombinant protein vaccine. Here, we report a DNA vaccine containing the spike gene for delivery via electroporation. The spike genes of SARS-CoV and SARS-CoV-2 were codon optimized for mammalian cell expression and then cloned into mammalian cell expression vectors, called pSARS-S and pSARS2-S, respectively. Spike protein expression was confirmed by immunoblotting after transient expression in HEK293T cells. After immunization, sera were collected for antigen-specific antibody and neutralizing antibody titer analyses. We found that both pSARS-S and pSARS2-S immunization induced similar levels of antibodies against S2 of SARS-CoV-2. In contrast, only pSARS2-S immunization induced antibodies against the receptor-binding domain of SARS-CoV-2. We further found that pSARS2-S immunization, but not pSARS-S immunization, could induce very high titers of neutralizing antibodies against SARS-CoV-2. We further analyzed SARS-CoV-2 S protein-specific T cell responses and found that the immune responses were biased toward Th1. Importantly, pSARS2-S immunization in hamsters could induce protective immunity against SARS-CoV-2 challenge in vivo. These data suggest that DNA vaccination could be a promising approach for protecting against COVID-19.


Assuntos
COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de DNA/normas , Animais , Chlorocebus aethiops , Cricetinae , Eletroporação , Células HEK293 , Humanos , Mesocricetus , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Plasmídeos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinas de DNA/imunologia , Células Vero
9.
Vaccines (Basel) ; 8(4)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096846

RESUMO

Peptide vaccines are safe, and aim to elicit and expand tumor-specific immunity so as to eradicate tumors. However, achieving strong and long-lasting anti-tumor immunity with peptide vaccines for the antigen-specific treatment of cancer is challenging, in part because their efficacy depends on strong adjuvants or immunomodulators. We approached this problem by conjugating an epitope-based cancer vaccine with a lipidated sequence (an immunomodulator) to elicit a strong immune response. Lipidated and non-lipidated polyepitope proteins were generated that contained the universal T helper cell epitope (pan-DR), B cell epitopes, and the extended loop sequence of extracellular domain 2 of tumor-associated antigen L6 (TAL6). We show that the lipidated polyepitope cancer vaccine can activate bone marrow-derived dendritic cells, and trigger effective antigen-specific antibody and T helper cell responses, more effectively than the non-lipidated vaccine. Moreover, potent T cell immune responses were elicited in mice inoculated with the lipidated polyepitope cancer vaccine, providing protective antitumor immunity in mice bearing TAL6 tumors. Our study demonstrates that a lipidated polyepitope cancer vaccine could be employed to generate potent anti-tumor immune responses, including humoral and cellular immunity, which could be beneficial in the treatment of TAL6+ cancer.

10.
Cancers (Basel) ; 12(4)2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32231003

RESUMO

Dendritic cells (DCs) are antigen-presenting cells involved in T cell activation and differentiation to regulate immune responses. Lipoimmunogens can be developed as pharmaceutical lipoproteins for cancer immunotherapy to target DCs via toll-like receptor 2 (TLR2) signaling. Previously, we constructed a lipoimmunogen, a lipidated human papillomavirus (HPV) E7 inactive mutant (rlipoE7m), to inhibit the growth of HPV16 E7-expressing tumor cells in a murine model. Moreover, this antitumor effect could be enhanced by a combinatory treatment with CpG oligodeoxynucleotides (ODN). To improve safety, we developed a rlipoE7m plus DOTAP liposome-encapsulated native phosphodiester CpG (POCpG/DOTAP) treatment to target DCs to enhance antitumor immunity. We optimized the formulation of rlipoE7m and POCpG/DOTAP liposomes to promote conventional DC and plasmacytoid DC maturation in vitro and in vivo. Combination of rlipoE7m plus POCpG/DOTAP could activate conventional DCs and plasmacytoid DCs to augment IL-12 production to promote antitumor responses by intravenous injection. In addition, the combination of rlipoE7m plus POCpG/DOTAP could elicit robust cytotoxic T lymphocytes (CTLs) by intravenous immunization. Interestingly, the combination of rlipoE7m plus POCpG/DOTAP could efficiently inhibit tumor growth via intravenous immunization. Moreover, rlipoE7m plus POCpG/DOTAP combined reduced the number of tumor-infiltrating regulatory T cells dramatically due to downregulation of IL-10 production by DCs. These results showed that the combination of rlipoE7m plus POCpG/DOTAP could target DCs via intravenous delivery to enhance antitumor immunity and reduce the number of immunosuppressive cells in the tumor microenvironment.

11.
J Am Chem Soc ; 141(46): 18455-18466, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674178

RESUMO

Salt-doped diblock copolymers with microphase-separated domains of both an ion conductive and a mechanically strong polymer have been extensively studied due to their potential in transport applications. Several unusual or counterintuitive trends regarding their transport properties have been observed experimentally, such as increasing ion conduction as a function of molecular weight. A crucial feature of these systems is the strong solvation of ions in the conducting microphase due to its higher dielectric constant. Here, we perform molecular dynamics simulations using a coarse-grained model that includes a 1/r4 potential form to generically represent ion solvation, allowing us to reproduce experimentally observed trends and explore their molecular underpinnings. We find that increasing ion concentration can increase or decrease ion diffusion, depending on solvation strength. We also show that the trend of increasing diffusion with molecular weight becomes more dramatic as ions are solvated in one polymer block more strongly or as the ion-ion interactions get stronger. In contrast to expectations, the interfacial width or the overlap of ions with the nonconductive polymer block does not adequately explain this phenomenon; instead, local ion agglomeration best explains reduced diffusion. Interfacial sharpening, controlled by the Flory χ parameter and molecular weight, tends to allow ions to spread more uniformly, and this increases their diffusion.

12.
Vaccine X ; 1: 100017, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-31384738

RESUMO

The tumor necrosis factor receptor associated protein 1 (TRAP1) is a mitochondria chaperon protein that has been previously implicated as a target for cancer therapy due to its expression level is linked to tumor progression. In this study, an immunodominant phosphopeptide of TRAP1 was identified from an HLA-A2 gene transfected mouse cancer cell line using mass spectrometry, and a synthetic phosphopeptide was generated to evaluate the potency on cancer immunotherapy. In the transporter associated with antigen processing (TAP) deficient cell, the conjugated phosphate group plays a critical role to enhance the binding affinity of phosphopeptide with HLA-A2 molecule. On the basis of immunological assay, immunization of synthetic phosphopeptide could induce a high frequency of IFN-γ-secreting CD8+ T cells in HLA-A2 transgenic mice, and the stimulated cytotoxic T lymphocytes showed a high target specificity to lysis the epitope-pulsed splenocytes in vivo and the human lung cancer cell in vitro. In a tumor challenge assay, vaccination of the HLA-A2 restricted phosphopeptide appeared to suppress the tumor growth and prolong the survival period of tumor-bearing mice. These results suggest that novel phosphopeptide is naturally presented as a HLA-A2-restricted CTL epitope and capable of being a potential candidate for the development of therapeutic vaccine against high TRAP1-expressing cancers.

13.
Phys Rev E ; 97(4-1): 042102, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29758638

RESUMO

We establish the kinetics of ballistic-to-diffusive (BD) transition observed in two-dimensional random walk using directional statistics. Directional correlation is parameterized using the walker's turning angle distribution, which follows the commonly adopted wrapped Cauchy distribution (WCD) function. During the BD transition, the concentration factor (ρ) governing the WCD shape is observed to decrease from its initial value. We next analytically derive the relationship between effective ρ and time, which essentially quantifies the BD transition rate. The prediction of our kinetic expression agrees well with the empirical datasets obtained from correlated random walk simulation. We further connect our formulation with the conventionally used scaling relationship between the walker's mean-square displacement and time.

14.
ACS Omega ; 3(1): 906-916, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457937

RESUMO

It has been demonstrated that atomic layer deposition (ALD) provides an initially safeguarding, uniform ultrathin film of controllable thickness for lithium-ion battery electrodes. In this work, CeO2 thin films were deposited to modify the surface of lithium-rich Li1.2Mn0.54Ni0.13Co0.13O2 (LRNMC) particles via ALD. The film thicknesses were measured by transmission electron microscopy. For electrochemical performance, ∼2.5 nm CeO2 film, deposited by 50 ALD cycles (50Ce), was found to have the optimal thickness. At a 1 C rate and 55 °C in a voltage range of 2.0-4.8 V, an initial capacity of 199 mAh/g was achieved, which was 8% higher than that of the uncoated (UC) LRNMC particles. Also, 60.2% of the initial capacity was retained after 400 cycles of charge-discharge, compared to 22% capacity retention of UC after only 180 cycles of charge-discharge. A robust kinetic of electrochemical reaction was found on the CeO2-coated samples at 55 °C through electrochemical impedance spectroscopy. The conductivity of 50Ce was observed to be around 3 times higher than that of UC at 60-140 °C. The function of the CeO2 thin-film coating was interpreted as being to increase substrate conductivity and to block the dissolution of metal ions during the charge-discharge process.

15.
Immunotherapy ; 9(4): 347-360, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28303764

RESUMO

Cancer immunotherapy is a growing field. GM-CSF, a potent cytokine promoting the differentiation of myeloid cells, can also be used as an immunostimulatory adjuvant to elicit antitumor immunity. Additionally, GM-CSF is essential for the differentiation of dendritic cells, which are responsible for processing and presenting tumor antigens for the priming of antitumor cytotoxic T lymphocytes. Some strategies have been developed for GM-CSF-based cancer immunotherapy in clinical practice: GM-CSF monotherapy, GM-CSF-secreting cancer cell vaccines, GM-CSF-fused tumor-associated antigen protein-based vaccines, GM-CSF-based DNA vaccines and GM-CSF combination therapy. GM-CSF also contributes to the regulation of immunosuppression in the tumor microenvironment. This review provides recommendations regarding GM-CSF-based cancer immunotherapy.


Assuntos
Vacinas Anticâncer/imunologia , Células Dendríticas/fisiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Imunoterapia/métodos , Neoplasias/terapia , Linfócitos T Citotóxicos/imunologia , Animais , Carcinogênese , Diferenciação Celular , Humanos , Imunidade , Imunoterapia/tendências , Ativação Linfocitária , Neoplasias/imunologia , Evasão Tumoral , Microambiente Tumoral , Vacinas de DNA
16.
J Control Release ; 233: 57-63, 2016 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-27164542

RESUMO

Synthetic liposomes provide a biocompatible and biodegradable approach for delivering drugs and antigens. In addition, self-adjuvanting recombinant lipoproteins (rlipoproteins) can enhance Th1 anti-tumor immune responses via the TLR2 signaling pathway. To generate a liposomal rlipoprotein for a cancer immunotherapeutic vaccine, we assessed 3 types of synthetic liposomes for use with the rlipoproteins rlipoE7m and rlipoOVA. We determined that the cationic liposome DOTAP could stabilize anionic rlipoproteins and delay rlipoprotein release. Surprisingly, rlipoproteins and DOTAP could synergistically up-regulate CD83 expression in bone marrow-derived dendritic cells (BMDCs). Compared with other liposome formulations, the rlipoprotein/DOTAP formulation elicited higher cytotoxic T-lymphocyte (CTL) responses. To explore the mechanism of BMDC activation by rlipoprotein/DOTAP, we assessed the production of reactive oxygen species (ROS) and the TNF-α secretion of BMDCs. We observed that rlipoprotein/DOTAP induced ROS to the same extent as DOTAP did. In addition, TLR2 signaling was also required for the TNF-α secretion of rlipoprotein/DOTAP-treated BMDCs. Moreover, compared with rlipoOVA-treated BMDCs, rlipoOVA/DOTAP-treated BMDCs increased the levels of IFN-γ produced by OVA-specific T cells. We also observed that rlipoE7m/DOTAP treatment but not rlipoE7m treatment delayed tumor growth. These results indicate that the rlipoprotein/DOTAP formulation can synergistically activate BMDCs via ROS and the TLR2 signaling pathway. In summary, rlipoprotein/DOTAP is a novel and stable formulation for cancer immunotherapy.


Assuntos
Vacinas Anticâncer/administração & dosagem , Lipoproteínas/administração & dosagem , Neoplasias/terapia , Ovalbumina/imunologia , Proteínas E7 de Papillomavirus/imunologia , Alérgenos/imunologia , Animais , Vacinas Anticâncer/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Dendríticas/imunologia , Ácidos Graxos Monoinsaturados/química , Lipoproteínas/imunologia , Lipoproteínas/uso terapêutico , Lipossomos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Neoplasias/patologia , Compostos de Amônio Quaternário/química , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico , Carga Tumoral/efeitos dos fármacos
17.
Oncotarget ; 7(21): 30804-19, 2016 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-27127171

RESUMO

The induction of long-lived effector CD8+ T cells is key to the development of efficient cancer vaccines. In this study, we demonstrated that a Toll-like receptor 2 (TLR2) agonist-fused antigen increased antigen presentation via TLR2 signaling and induced effector memory-like CD8+ T cells against cancer after immunization. The N-terminus of ovalbumin (OVA) was biologically fused with a bacterial lipid moiety TLR2 agonist to produce a recombinant lipidated ovalbumin (rlipo-OVA). We demonstrated that rlipo-OVA activated bone marrow-derived dendritic cells (BM-DCs) maturation and increased antigen presentation by major histocompatibility complex (MHC) class I via TLR2. After immunization, rlipo-OVA skewed the immune response towards T helper (Th) 1 and induced OVA-specific cytotoxic T lymphocyte (CTL) responses. Moreover, immunization with rlipo-OVA induced higher numbers of effector memory (CD44+CD62L-) CD8+ T cells compared with recombinant ovalbumin (rOVA) alone or rOVA mixed with the TLR2 agonist Pam3CSK4. Accordingly, the CD27+CD43+ effector memory CD8+ T cells expressed high levels of the long-lived CD127 marker. The administration of rlipo-OVA could inhibit tumor growth, but the anti-tumor effects were lost after the depletion of CD8 or CD127 cells in vivo. These findings suggested that the TLR2 agonist-fused antigen induced long-lived memory CD8+ T cells for efficient cancer therapy.


Assuntos
Apresentação do Antígeno/imunologia , Vacinas Anticâncer/imunologia , Leucemia Experimental/terapia , Ovalbumina/imunologia , Proteínas Recombinantes de Fusão/imunologia , Linfócitos T Citotóxicos/imunologia , Receptor 2 Toll-Like/agonistas , Animais , Células da Medula Óssea/imunologia , Antígenos CD8/metabolismo , Vacinas Anticâncer/uso terapêutico , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Feminino , Antígenos de Histocompatibilidade Classe I/imunologia , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Leucemia Experimental/imunologia , Lipopeptídeos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Transdução de Sinais/imunologia , Linfócitos T Citotóxicos/metabolismo , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo
18.
Nanotechnology ; 26(16): 165301, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25815515

RESUMO

In this paper, a sandwich structure comprising a SiO2 capping layer, amorphous Germanium (a-Ge) nanodots (NDs), and a pit-patterned Silicon (Si) substrate is developed, which is then annealed by utilizing a pulsed ultraviolet excimer laser in order to fabricate an array of pure, single crystal Ge NDs at room temperature. A wide bandgap SiO2 capping layer is used as a transparent thermally isolated layer to prevent thermal loss and Si-Ge intermixing. The two-dimensional pit-patterned Si substrate is designed to confine the absorbed laser energy, reduce the melting point, and block the surface migration of the Ge. After optimizing the laser radiation parameters such that the laser energy density is 200 mJ cm(-2), the laser annealing period is 10 s, and the number of laser shots is 10, pure, single crystal Ge NDs that have both a regular arrangement and a uniform size distribution are obtained in the pits of the Si substrates. The Raman spectrum shows a highly symmetric Ge transversal optical peak with a full width at half maximum of 4.2 cm(-1) at 300.7 cm(-1), which is close to that of the original Ge wafer. In addition, the high-resolution transmission electron microscopy image for the Ge NDs and the corresponding selected area electron diffraction pattern shows a clear single crystalline structure without any impurities.

19.
Expert Rev Vaccines ; 14(3): 383-94, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25455657

RESUMO

The goal of therapeutic HPV vaccines is the induction of cytotoxic T lymphocyte immunity against HPV-associated cancers. Recombinant proteins and synthetic peptides have high safety profiles but low immunogenicity, which limits their efficacy when used in a vaccine. Self-adjuvanting lipid moieties have been conjugated to synthetic peptides or expressed as lipoproteins to enhance the immunogenicity of vaccine candidates. Mono-, di- and tri-palmitoylated peptides have been demonstrated to activate dendritic cells and induce robust cellular immunity against infectious diseases and cancer. Recently, a platform technology using the high-yield production of recombinant lipoproteins with Toll-like receptor 2 agonist activity was established for the development of novel subunit vaccines. This technology represents a novel strategy for the development of therapeutic HPV vaccines. In this review, we describe recent progress in the design of therapeutic HPV vaccines using lipoimmunogens.


Assuntos
Antígenos Virais/imunologia , Imunoterapia Ativa/métodos , Lipoproteínas/imunologia , Infecções por Papillomavirus/terapia , Vacinas contra Papillomavirus/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/isolamento & purificação , Antígenos Virais/administração & dosagem , Antígenos Virais/isolamento & purificação , Humanos , Lipoproteínas/administração & dosagem , Lipoproteínas/isolamento & purificação , Papillomaviridae/imunologia , Vacinas contra Papillomavirus/administração & dosagem , Vacinas contra Papillomavirus/isolamento & purificação , Vacinas de Subunidades/administração & dosagem , Vacinas de Subunidades/imunologia , Vacinas de Subunidades/isolamento & purificação
20.
Hum Vaccin Immunother ; 10(11): 3241-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25483652

RESUMO

It has been reported that lipopeptides can be used to elicit cytotoxic T lymphocyte (CTL) responses against viral diseases and cancer. In our previous study, we determined that mono-palmitoylated peptides can enhance anti-tumor responses in the absence of adjuvant activity. To investigate whether di-palmitoylated peptides with TLR2 agonist activity are able to induce anti-tumor immunity, we synthesized a di-palmitic acid-conjugated long peptide that contains a murine CTL epitope of HPV E749-57 (Pam2IDG). Pam2IDG stimulated the maturation of bone marrow-derived dendritic cells (BMDCs) through TLR2/6. After immunization, Pam2IDG induced higher levels of T cell responses than those obtained with its non-lipidated counterpart (IDG). In the prophylactic model, Pam2IDG immunization completely inhibited tumor growth, whereas IDG immunization was unable to inhibit tumor growth. However, Pam2IDG immunization could not effectively inhibit the growth of established tumors. Therefore, we further investigated whether the depletion of immunosuppressive factors could improve the therapeutic effects of Pam2IDG. Our data indicate that treatment with Pam2IDG combined with clodronate/liposome delays tumor growth and increases the survival rate. We also observed that the therapeutic effects of Pam2IDG are improved by diminishing the function of tumor-associate macrophages (TAMs) and through the use of an IL10 receptor blocking antibody or a Cyclooxygenase 2 (Cox-2) inhibitor. In conclusion, the depletion of TAMs may enhance the anti-tumor immunity of a TLR2 agonist-conjugated peptide.


Assuntos
Lipopeptídeos/uso terapêutico , Macrófagos/imunologia , Neoplasias/imunologia , Linfócitos T Citotóxicos/imunologia , Receptor 2 Toll-Like/agonistas , Animais , Anticorpos Bloqueadores/imunologia , Anticorpos Bloqueadores/uso terapêutico , Ácido Clodrônico/uso terapêutico , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Células Dendríticas/imunologia , Imunização , Imunoterapia , Lipopeptídeos/imunologia , Lipoilação , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/terapia , Ácido Palmítico/química , Ácido Palmítico/imunologia , Proteínas E7 de Papillomavirus/química , Proteínas E7 de Papillomavirus/imunologia , Receptores de Interleucina-10/antagonistas & inibidores , Receptores de Interleucina-10/imunologia , Taxa de Sobrevida , Receptor 2 Toll-Like/imunologia , Receptor 6 Toll-Like/imunologia
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