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1.
Microb Pathog ; 176: 106007, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36709850

RESUMEN

Staphylococcus aureus is a gram-positive bacterium, representing one of the most important nosocomial pathogens. The treatment of infections, caused by S. aureus, has become increasingly intricate due to the emergence of highly resistant strains. Therefore, it is obvious that an effective prevention strategy against this bacterium could significantly decrease such infections. In the present study, the protective efficacy and immunological properties of recombinant autolysin, formulated in Montanide ISA266 and Alum adjuvants with Glucomannan as a polysaccharide, were assessed in the systemic mouse model of infection. Mice were immunized with the purified recombinant protein in various formulations in different groups and, subsequently, mice were challenged with 5 × 108 CFU of bacteria for the evaluation of their survival and bacterial clearances in the internal organs. ELISA was performed to determine the type of induced immunity, cytokine secretion (IFN-γ, IL-4, IL-2, and IL-17), and isotyping (IgG1 and IgG2a). In addition, we measured the opsonophagocytic activities of the antibodies. Results showed that immunization with r-autolysin + Alum + Glucomannan and r-autolysin + MontanideISA266+Glucomannan formulations significantly increased total IgG and isotypes (IgG1 and IgG2a), as compared with other vaccinated and control groups. Furthermore, the formulation of r-autolysin in Alum and MontanideISA266 adjuvants with Glucomannan enhanced IFN-γ, IL-4, and IL-17 cytokine secretion as well as protectivity, following experimental challenge. We concluded that Glucomannan has the potential to induce immune responses and would be used as an adjuvant factor in vaccine formulation.


Asunto(s)
Interleucina-17 , Staphylococcus aureus , Animales , Ratones , Interleucina-4 , N-Acetil Muramoil-L-Alanina Amidasa , Adyuvantes Inmunológicos , Adyuvantes Farmacéuticos , Mananos , Proteínas Recombinantes , Inmunoglobulina G , Inmunidad , Ratones Endogámicos BALB C
2.
World J Microbiol Biotechnol ; 39(1): 16, 2022 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-36401129

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the leading causes of hospital-acquired infections worldwide, which is resistant to many antibiotics, resulting in significant mortality in societies. Vaccination is a well-known approach to preventing disease. Autolysin, a surface-associated protein in S. aureus with multiple functions, is a suitable candidate for vaccine development. As a co-adjuvant, selenium nanoparticles (SeNPs) can increase the immune system, presumably resulting in increased vaccine efficacy. The present study evaluated the immunogenicity and defense of recombinant autolysin formulated in SeNPs and Alum adjuvants against MRSA. r-Autolysin was expressed and purified by the Ni-NTA affinity chromatography. SeNPs were synthetically obtained from sodium dioxide, followed by an assessment of shape and size using SEM and DLS. Balb/c mice were injected subcutaneously with 20 mg of r-autolysin formulated in Alum and SeNps adjuvants three times with the proper control group in 2 weeks intervals. Cytokine profile and isotyping ELISA were conducted to determine the type of induced immunity. Opsonophagocytosis tests assessed the functional activity of the vaccine, and the bacterial burden from the infected tissues was determined. Results showed that mice receiving SeNps and r-Autolysin had higher levels of total IgG and isotypes (IgG1 and IgG2a) and increased cytokine levels (IFN-γ, TNF-α, IL-12, and IL-4) as compared with those only receiving autolysin and PBS as a control. More importantly, mice immunized with SeNps and r-Autolysin exhibited a decrease in mortality and bacterial burden compared to the control group. We concluded that SeNps could stimulate immune responses and can be used as an adjuvant element in vaccine formulation.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Nanopartículas , Selenio , Ratones , Animales , Selenio/farmacología , N-Acetil Muramoil-L-Alanina Amidasa , Staphylococcus aureus , Ratones Endogámicos BALB C , Nanopartículas/química , Inmunoglobulina G , Citocinas , Inmunidad
3.
Microb Pathog ; 157: 104953, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34044042

RESUMEN

Methicillin resistant Staphylococcus aureus is one of the most common causes of nosocomial infections. Current therapeutic approaches are not always effective in treatment of nosocomial infections, thus, there is a global demand for the development of novel therapeutic strategies. Staphylococcus aureus possesses various systems to uptake iron. One of the most important of them is iron regulated surface determinant (Isd) which can be an excellent candidate for immunization. Here, following the preparation of recombinant IsdE protein, 20 µg of r-IsdE prepared in various formulations were subcutaneously injected in different groups of mice. Two booster vaccinations were administered in two-week intervals, then, blood samples were collected two weeks after each injection. ELISA was used for the evaluation of total IgG and its isotypes (IgG1 and IgG2a) as well as quantity of IFN-γ, IL-4, IL-17, IL-2 and TNF-α cytokines on the serum samples. Meanwhile, the immunized mice were intraperitoneally inoculated with 5 × 108 CFU of bacteria then, their mortality rate and bacterial load were assessed. Our results showed that immunization with the r-IsdE in various formulations raised total IgG and isotypes (IgG1 and IgG2a) compared with the control groups. Moreover, r-IsdE formulation with MF59 and Freund adjuvants raised production of IFN-γ, IL-4, IL-17, IL-2 and TNF-α cytokines and provided an acceptable protection against Staphylococcus aureus infections. Results of present study suggest that r-IsdE which can easily be expressed by Escherichia coli BL21 system shows a great potential to develop a protective immunity against infections caused by Methicillin resistant Staphylococcus aureus.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Vacunas , Animales , Clonación Molecular , Staphylococcus aureus Resistente a Meticilina/genética , Ratones , Ratones Endogámicos BALB C , Infecciones Estafilocócicas/prevención & control , Staphylococcus aureus/genética
4.
Immunol Invest ; 49(8): 875-896, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31856615

RESUMEN

Despite the existence of vaccination, antibiotic therapy, and antibody therapies, infectious diseases still remain as one of the biggest challenges to human health all over the world. Among the different methods for treatment and prevention of infectious diseases, antibodies are well known but poorly developed. There is a new subclass of antibodies calledheavy-chain antibodies that belong to the IgG isotype. However, they are low in molecular weight and lost the first constant domain (CH1). Their single-domain antigen-binding fragments, identified as nanobodies, have unique characteristics, which make them superior in comparison with the conventional antibodies. Low molecular weight and small size, high stability and solubility, ease of expression, good tissue penetration, and low-cost production make nanobodies an appropriate alternative to use against infectious disease. In this research, we review the properties of nanobodies and their potential applications in controlling human infections and inflammations.


Asunto(s)
Enfermedades Transmisibles/diagnóstico , Enfermedades Transmisibles/terapia , Control de Infecciones , Anticuerpos de Dominio Único/farmacología , Anticuerpos de Dominio Único/uso terapéutico , Manejo de la Enfermedad , Farmacorresistencia Microbiana/efectos de los fármacos , Humanos , Control de Infecciones/métodos , Anticuerpos de Dominio Único/inmunología , Resultado del Tratamiento
5.
Microb Pathog ; 127: 159-165, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30521844

RESUMEN

Staphylococcus aureus is a human commensal and pathogen, its clinical importance is exacerbated by the spread of multi-drug resistant strains. The potential future failure of antibiotic therapy necessitates the development of novel control regimes, including new immunotherapeutic approaches. S. aureus has a large repertoire of surface components with potential for immunological targeting. The aim of this study was to evaluate the efficacy of a novel member of staphylococcal conserved antigen family (ScaF) as a factor to elicit cellular and humoral immunity. To determine the ScaF potential as a vaccine candidate, experimental groups of mice were immunized with recombinant Scaf (r-ScaF) formulated in Freund's and alum adjuvants or PBS and subsequently challenged in the sepsis model of S. aureus disease. The vaccine formulations induced robust cellular cytokines responses, including IFN-γ and IL-17, as well as increased production of IgG2a rather than other subclass of IgGs. Active immunization with r-ScaF with adjuvants led to decreased mortality of infected mice and a lower associated bacterial burden in the internal organs in comparison to the control group. Taken together, our Results indicate to the possibility of the r-ScaF protein to be considered as an important component of a multivalent prophylactic vaccine candidate.


Asunto(s)
Antígenos Bacterianos/inmunología , Vacunas Bacterianas/inmunología , Staphylococcus aureus Resistente a Meticilina/inmunología , Infecciones Estafilocócicas/prevención & control , Adyuvantes Inmunológicos/administración & dosificación , Estructuras Animales/microbiología , Animales , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/genética , Carga Bacteriana , Vacunas Bacterianas/administración & dosificación , Vacunas Bacterianas/genética , Citocinas/análisis , Modelos Animales de Enfermedad , Inmunidad Celular , Inmunidad Humoral , Inmunoglobulina G/sangre , Staphylococcus aureus Resistente a Meticilina/genética , Ratones , Sepsis/inmunología , Sepsis/prevención & control , Infecciones Estafilocócicas/inmunología , Análisis de Supervivencia , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología
6.
Microb Pathog ; 108: 32-39, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28457901

RESUMEN

Methicillin-resistant Staphylococcus aureus infections are focal and development of an effective vaccine can help to control this infection. Here, recombinant PBP2a was studied in mouse model. Following the preparation of recombinant PBP2a, Balb/c mice were injected subcutaneously with 20 µg of r-PBP2a formulated in Freund's adjuvant three times with three weeks intervals with proper control group. Total and specific isotype antibodies were evaluated on sera by ELISA. Opsonophagocytic activity was also investigated on the sera samples. Intraperitonealchallenge with a sub-lethal dose of MRSA (5 × 108 CFU) was done in experimental mice. Following that, the number of bacteria from kidneys of experimental mice were determined. Survival rate was recorded for 60 days. Significant increase of antibody with high level of IgG1, IgG2a and IgG2b isotypes was demonstrated in vaccinated mice versus the control group (P < 0.005). The bacterial load in the kidneys from immunized mice was 1000 times less thancontrol group (PBS) and opsonophagocytic activity of immunized mice sera significantly increased (P < 0.0001). Finally the life span of immunized mice after bacterial challenge was extended versus control mice. These results may indicate the capacity of PBP2a as a candidate vaccine to control the MRSA infections.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/inmunología , Proteínas de Unión a las Penicilinas/genética , Proteínas de Unión a las Penicilinas/inmunología , Infecciones Estafilocócicas/inmunología , Vacunas Estafilocócicas/genética , Vacunas Estafilocócicas/inmunología , Vacunas Sintéticas/uso terapéutico , Animales , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Carga Bacteriana , Clonación Molecular , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Inmunidad Humoral/inmunología , Inmunoglobulina G/sangre , Isotipos de Inmunoglobulinas/inmunología , Riñón/efectos de los fármacos , Riñón/microbiología , Ratones , Ratones Endogámicos BALB C , Alineación de Secuencia , Análisis de Secuencia , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/prevención & control , Tasa de Supervivencia , Vacunación , Vacunas Sintéticas/genética
7.
J Nanosci Nanotechnol ; 15(12): 10165-72, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26682463

RESUMEN

The modification of tumor-associated antigen-based vaccine to elicit a more robust immune response has been addressed in several ways. In the present work, we aimed to investigate the immunomodulatory effect of selenium nanoparticles as an immunoadjuvant in formulation of a tumor-associated antigen-based vaccine in a preventive form. Fortyfive female inbred BALB/c mice five-to-seven weeks old were used and divided into three groups of test and control, each containing fifteen mice. Group one injected by PBS and used as a control. Group two injected by breast tumor cell lysate alone as vaccine. Group three injected by SeNPs with tumor cell lysate as vaccine. All injections were carried out on day fourteen, twentyone and twentyeight of the study. Tumor induction was done at day thirty. Twenty days after tumor induction serum samples were gathered to measure the cytokine assay. Tumor growth and weight of mice as well as delayed type hyper sensitivity (DTH) response were monitored during the study. Results of the present work showed a significant increase in the level of serum IFN-γ, IL-2, IL-12 and decreased TGF-ß in SeNPs/vaccine injected mice as well as lower tumor volume, more potent DTH responses and longer survival rate in comparison to control and tumor lysate vaccine. Taken together, it can be deduced from this work that SeNPs can be considered as an adjuvant in vaccine in triggering robust immune response against breast cancer. But further evaluations are still needed to find the best formula for this agent in antitumor vaccines.


Asunto(s)
Neoplasias de la Mama/terapia , Vacunas contra el Cáncer/química , Nanopartículas/química , Selenio/química , Animales , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos BALB C , Neoplasias Experimentales/terapia
8.
Immunol Res ; 72(3): 490-502, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38383811

RESUMEN

To increase the effectiveness of methicillin-resistant Staphylococcus aureus vaccines (MRSA), a new generation of immune system stimulating adjuvants is necessary, along with other adjuvants. In some vaccines, monophosphoryl lipid A (MPLA) as a toll-like receptor 4 agonist is currently used as an adjuvant or co-adjuvant. MPLA could increase the immune response and vaccine immunogenicity. The current investigation assessed the immunogenicity and anti-MRSA efficacy of recombinant autolysin formulated in MPLA and Alum as co-adjuvant/adjuvant. r-Autolysin was expressed and purified by Ni-NTA affinity chromatography and characterized by SDS-PAGE. Then, the vaccine candidate formulation in MPLAs and Alum was prepared. To investigate the immunogenic responses, total IgG, isotype (IgG1 and IgG2a) levels, and cytokines (IL-4, IL-12, TNF-α, and IFN-γ) profiles were evaluated by ELISA. Also, the bacterial burden in internal organs, opsonophagocytosis, survival rate, and pathobiology changes was compared among the groups. Results demonstrated that mice immunized with the r-Autolysin + Alum + MPLA Synthetic and r-Autolysin + Alum + MPLA Biologic led to increased levels of opsonic antibodies, IgG1, IgG2a isotype as well as increased levels of cytokines profiles, as compared with other experimental groups. More importantly, mice immunized with MPLA and r-Autolysin exhibited a decrease in mortality and bacterial burden, as compared with the control group. The highest level of survival was seen in the r-Autolysin + Alum + MPLA Synthetic group. We concluded that both MPLA forms, synthetic and biological, are reliable candidates for immune response improvement against MRSA infection.


Asunto(s)
Adyuvantes Inmunológicos , Anticuerpos Antibacterianos , Modelos Animales de Enfermedad , Inmunoglobulina G , Lípido A , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Vacunas Estafilocócicas , Animales , Lípido A/análogos & derivados , Lípido A/inmunología , Lípido A/administración & dosificación , Lípido A/farmacología , Ratones , Staphylococcus aureus Resistente a Meticilina/inmunología , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/prevención & control , Vacunas Estafilocócicas/inmunología , Vacunas Estafilocócicas/administración & dosificación , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Femenino , Citocinas/metabolismo , N-Acetil Muramoil-L-Alanina Amidasa/inmunología , Desarrollo de Vacunas , Compuestos de Alumbre/administración & dosificación , Ratones Endogámicos BALB C , Adyuvantes de Vacunas , Humanos
9.
Daru ; 21(1): 33, 2013 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-23631392

RESUMEN

BACKGROUND AND THE PURPOSE OF THE STUDY: Selenium enriched Lactobacillus has been reported as an immunostimulatory agent which can be used to increase the life span of cancer bearing animals. Lactic acid bacteria can reduce selenium ions to elemental selenium nanoparticles (SeNPs) and deposit them in intracellular spaces. In this strategy two known immunostimulators, lactic acid bacteria (LAB) and SeNPs, are concomitantly administered for enhancing of immune responses in cancer bearing mice. METHODS: Forty five female inbred BALB/c mice were divided into three groups of tests and control, each containing 15 mice. Test mice were orally administered with SeNP-enriched Lactobacillus brevis or Lactobacillus brevis alone for 3 weeks before tumor induction. After that the administration was followed in three cycles of seven days on/three days off. Control group received phosphate buffer saline (PBS) at same condition. During the study the tumor growth was monitored using caliper method. At the end of study the spleen cell culture was carried out for both NK cytotoxicity assay and cytokines measurement. Delayed type hypersensitivity (DTH) responses were also assayed after 72h of tumor antigen recall. Serum lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) levels were measured, the livers of mice were removed and prepared for histopathological analysis. RESULTS: High level of IFN-γ and IL-17 besides the significant raised in NK cytotoxicity and DTH responses were observed in SeNP-enriched L. brevis administered mice and the extended life span and decrease in the tumor metastasis to liver were also recorded in this group compared to the control mice or L.brevis alone administered mice. CONCLUSION: Our results suggested that the better prognosis could be achieved by oral administration of SeNP-enriched L. brevis in highly metastatic breast cancer mice model.

10.
Iran J Microbiol ; 15(4): 557-564, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38045713

RESUMEN

Background and Objectives: The increasing number of methicillin-resistant Staphylococcus aureus persuade the need for preventive measures. Glucomannan is a polysaccharide choice for developing immunological strategies. This study aimed to investigate changes in gene expression and phagocytic activity of macrophage cells in the presence of glucomannan. Materials and Methods: The effect of different concentrations of glucomannan (25, 50, and 100 µg/mL) on the phagocytic activity of macrophage cells was measured using the colony count method. The expression of Tumor Necrosis Factor-alpha (TNF-α) and Inducible Nitric Oxide Synthase (iNOS) genes was evaluated by Real-Time PCR. Results: The concentrations of glucomannan significantly reduced the bacterial Colony-Forming Unit (CFU) and increased the phagocytic activity of macrophage cells. The maximum effect of glucomannan on iNOS and TNF-A genes expression was 100 µg/mL. Conclusion: Glucomannan should be considered an adjuvant that stimulates the immune system. It may increase the expression of TNF-α and iNOS genes and the phagocytic activity of macrophage cells against methicillin-resistant Staphylococcus aureus.

11.
Vaccines (Basel) ; 11(1)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36679991

RESUMEN

Triple-negative breast cancer (TNBC) is the subtype of breast cancer with the poorest outcomes, and is associated with a high risk of relapse and metastasis. The treatment choices for this malignancy have been confined to conventional chemotherapeutic agents, due to a lack of expression of the canonical molecular targets. Immunotherapy has been recently changing the treatment paradigm for many types of tumors, and the approach of evoking active immune responses in the milieu of breast tumors through cancer vaccines has been introduced as one of the most novel immunotherapeutic approaches. Accordingly, a number of vaccines for the treatment or prevention of recurrence have been developed and are currently being studied in TNBC patients, while none have yet received any approvals. To elucidate the efficacy and safety of these vaccines, we performed a systematic review of the available literature on the topic. After searching the PubMed, Scopus, Web of Science, Embase, Cochrane CENTRAL, and Google Scholar databases, a total of 5701 results were obtained, from which 42 clinical studies were eventually included based on the predefined criteria. The overall quality of the included studies was acceptable. However, due to a lack of reporting outcomes of survival or progression in some studies (which were presented as conference abstracts) as well as the heterogeneity of the reported outcomes and study designs, we were not able to carry out a meta-analysis. A total of 32 different vaccines have so far been evaluated in TNBC patients, with the majority belonging to the peptide-based vaccine type. The other vaccines were in the cell or nucleic acid (RNA/DNA)-based categories. Most vaccines proved to be safe with low-grade, local adverse events and could efficiently evoke cellular immune responses; however, most trials were not able to demonstrate significant improvements in clinical indices of efficacy. This is in part due to the limited number of randomized studies, as well as the limited TNBC population of each trial. However, due to the encouraging results of the currently published trials, we anticipate that this strategy could show its potential through larger, phase III randomized studies in the near future.

12.
Front Biosci (Landmark Ed) ; 28(5): 88, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37258481

RESUMEN

BACKGROUND: Streptococcus mutans is a major component of dental plaque, contributing to cariogenic biofilm formation and inducing dental caries. Attempts have recently been made to use postbiotic mediators (PMs) to prevent dental caries. This research evaluated the antimicrobial/antibiofilm activity of PMs derived from Lactobacillus rhamnosus GG (LGG) and Lactobacillus reuteri (LR) against S. mutans in vitro. METHODS: PMs were obtained from the Lactobacilli supernatants. The minimum inhibitory concentration, minimum bactericidal concentration, antibiofilm potential, and metabolic activity of PMs against S. mutans were evaluated using CFU/mL, scanning electron microscopy, and XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) reduction assay. The expression of gtfB gene as one of the most important genes involved in S. mutans biofilm formation was also measured using qRT-PCR. RESULTS: CFU score was reduced by both PMs, but the reduction was only significant in LGG (p = 0.02). Both PMs caused a significant decrease in the metabolic activity of S. mutans compared with the controls (p ≤ 0.002). S. mutans treated with LGG PMs exhibited more destructive effects than LR PMs (p > 0.05). S. mutans gtfB gene expression was significantly downregulated when treated with the PMs obtained from both LGG and LR (p = 0.01 for both). CONCLUSIONS: We showed that PMs isolated from two Lactobacillus strains inhibited S. mutans biofilm, metabolic activity, and gtfB gene expression. Therefore, these derivatives may be a suitable biofilm-destruction agent against S. mutants. However, the oral environment is a complex ecosystem that needs further investigation.


Asunto(s)
Antiinfecciosos , Caries Dental , Lacticaseibacillus rhamnosus , Limosilactobacillus reuteri , Humanos , Streptococcus mutans/genética , Caries Dental/prevención & control , Ecosistema , Lactobacillus
13.
Proc Inst Mech Eng H ; 237(8): 1008-1016, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37477395

RESUMEN

The mechanical properties of tissue scaffolds are essential in providing stability for tissue repair and growth. Thus, the ability of scaffolds to withstand specific loads is crucial for scaffold design. Most research on scaffold pores focuses on grids with pore size and gradient structure, and many research models are based on scaffolding with vertically arranged holes. However, little attention is paid to the influence of the distribution of holes on the mechanical properties of the scaffold. To address this gap, this research investigates the effect of pore distribution on the mechanical properties of tissue scaffolds. The study involves four types of scaffold designs with regular and staggered pore arrangements and porosity ranging from 30% to 80%. Finite element analysis (FEA) was used to compare the mechanical properties of different scaffold designs, with von-Mises stress distribution maps generated for each scaffold. The results show that scaffolds with regular vertical holes exhibit a more uniform stress distribution and better mechanical performance than those with irregular holes. In contrast, the scaffold with a staggered arrangement of holes had a higher probability of stress concentration. The study emphasized the importance of balancing porosity and strength in scaffold design.


Asunto(s)
Ingeniería de Tejidos , Andamios del Tejido , Andamios del Tejido/química , Ingeniería de Tejidos/métodos , Análisis de Elementos Finitos , Porosidad , Huesos
14.
Galen Med J ; 12: 1-9, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38774842

RESUMEN

BACKGROUND: Leukemia remains a global health challenge, requiring the exploration of alternative therapies with reduced side effects. Probiotics, particularly Lactobacillus species, have gained attention because of their potential anticancer properties. This study investigated the anticancer and cytotoxic effects of postbiotic mediators (PMs) derived from Lactobacillus rhamnosus GG (LGG) and Lactobacillus reuteri (LR) on acute lymphoblastic leukemia (ALL) cells and peripheral blood mononuclear cells (PBMCs). MATERIALS AND METHODS: The PMs were prepared by culturing LGG and LR strains and isolating the supernatant. The MTT assay assessed cell viability on ALL Jurkat cells and PBMCs, and apoptosis analysis was conducted using flow cytometry. Quantitative real-time PCR was also performed to analyze BAX, BCL-2, BCLX, FAS, and p27 gene expression levels. RESULTS: The results showed that PMs derived from LGG and LR significantly reduced cell viability in Jurkat cells (P0.05) but not PBMCs (P0.05). Apoptosis analysis revealed an increase in apoptotic cells after PMs treatment. Nevertheless, gene expression analysis revealed no statistically significant difference between the treated and untreated groups in BAX, BCL-2, BCLX, FAS, and p27 gene expression levels (P0.05). CONCLUSION: Findings suggest that specific PMs derived from LGG and LR possess anticancer properties against ALL cells. This research highlighted the promise of PMs as a cutting-edge and less toxic adjuvant therapeutic strategy in cancer treatment.

15.
Vaccines (Basel) ; 10(10)2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36298611

RESUMEN

Konjac glucomannan (KGM) is a water-soluble polysaccharide derived from the Amorphophallus's tuber and, as herbal medicine has shown, can suppress tumor growth or improve health. However, there has been no investigation into the effects of KGM on breast tumor-bearing mice. Therefore, in two cohort experiments, we assessed the effect of glucomannan at daily doses of 2 and 4 mg for 28 days as a dietary supplement and also glucomannan in combination with tumor lysate vaccine as an adjuvant. Tumor volume was monitored twice weekly. In addition, TNF-α cytokines and granzyme B (Gr-B) release were measured with ELISA kits, and IL-2, IL-4, IL-17, and IFN-γ were used as an index for cytotoxic T lymphocyte activity. Moreover, TGF-ß and Foxp3 gene expression were assessed in a real-time PCR test. The results show that glucomannan as a dietary supplement increased the IFN-γ cytokine and Th1 responses to suppress tumor growth. Glucomannan as a dietary supplement at the 4 mg dose increased the IL-4 cytokine response compared to control groups. In addition, cell lysate immunization with 2 or 4 mg of glucomannan suppressed tumor growth. As an adjuvant, glucomannan at both doses showed 41.53% and 52.10% tumor suppression compared with the PBS group. Furthermore, the administration of glucomannan as a dietary supplement or adjuvant reduced regulatory T cell response through decreasing TGF-ß and Foxp3 gene expression in the tumor microenvironment. In conclusion, glucomannan as a dietary supplement or adjuvant enhanced the immune responses of tumor-bearing mice and decreased immune response suppression in the tumor milieu, making it a potentially excellent therapeutic agent for lowering breast tumor growth.

16.
Daru ; 29(1): 159-170, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33880740

RESUMEN

BACKGROUND: Polychlorinated biphenyls (PCBs) are a group of synthetic organic chlorine compounds known as an organic pollutant in food sources, which play important roles in malignancies. The present study aimed to investigate the direct effects of prevalent PCBs in food in hormone-responsive and non-responsive cell lines. METHODS: In the current study, MCF-7, LNCap, and MDA-MB231 cell lines were treated with serial concentrations (0.001-100 µM) of PCBs for 48 h and cell viability assessment was performed using MTT assay. The best concentration then applied and the expression level of PON1 was evaluated using real-time PCR. Besides, molecular docking was performed to determine the binding mechanism and predicted binding energies of PBCs compounds to the AhR receptor. RESULTS: Unlike MCF-7 and LNCap cells, the viability of MDA-MB231 cells did not significantly change by different concentrations of PCBs. Meanwhile, quantitative gene expression analysis showed that the PON1 was significantly more expressed in MCF-7 and LNCap lines treated with PCB28 and PCB101. However, the expression level of this gene in other groups and also MDA-MB231cells did not demonstrate any significantly change. Also, the results of molecular docking showed that PBCs had steric interaction with AhR receptor. CONCLUSIONS: Current results showed that despite of hormone non-responsive cells the PCBs have a significant positive effect on hormone-responsive cell. Therefore, and regarding to the existence of PCBs contamination in food there should be serious concern about their impact on the prevalence of different malignancies which certainly should result in a standard limit for this material. This study aimed to investigate the direct effects of prevalent PCBs in food in hormone-responsive and non-responsive cell lines. Cell lines were treated with serial concentrations of PCBs and cell viability assessment was performed using MTT assay. The expression level of PON1 was evaluated using real-time PCR. Molecular docking was performed to determine the binding mechanism and predicted binding energies of PBCs compounds to the AhR receptor. PCBs contamination in food there should be serious concern about their impact on the prevalence of different malignancies which certainly should result in a standard limit for this material.


Asunto(s)
Contaminantes Ambientales/farmacología , Contaminación de Alimentos , Bifenilos Policlorados/farmacología , Arildialquilfosfatasa/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Humanos , Simulación del Acoplamiento Molecular , Unión Proteica , Receptores de Hidrocarburo de Aril/metabolismo
17.
APMIS ; 129(8): 480-488, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33539574

RESUMEN

The potency of a vaccine highly depends upon the nature of the adjuvant used. There are a variety of ineffective vaccines, such as HIV-1 vaccine candidates, that need to be optimized with new adjuvant formulations to improve vaccine potency and efficacy. Studies show the potency of naloxone (NLX)/alum mixture in the induction of Th1/Th2 response for vaccine. However, other immunologic patterns inducing by this adjuvant and its immunoregulatory effect is unclear. In this regard, the aim of the present study was to investigate the effect of the NLX/alum mixture, as an adjuvant, on cytokine networks and immunoregulatory activity for an HIV-1 polytope vaccine. BALB/c mice were divided into six groups (n = 6) and immunized subcutaneously with 10 µg of the vaccine formulated with NLX/alum, NLX, alum, and Freund's adjuvants. At the same time, the mice in the control groups received an equal volume of PBS or NLX. The lymphocyte proliferation assay was carried out using the BrdU method. ELISA was used to measure the levels of IFN-γ, IL-2, IL-4, IL-10, IL-12, and IL-17 cytokines, total IgG, as well as IgG1 and IgG2a subtypes in serum samples. Our findings showed that mice receiving the NLX/alum-adjuvanted vaccine exhibited increased antibody levels compared with other groups. In addition, there was a considerable difference in the levels of IgG1, IgG2a, IFN-γ, IL-2, IL-10, IL-12, and IL-17 in mice receiving the NLX/alum-adjuvanted vaccine as compared with other groups. The NLX/alum mixture, as an adjuvant, may have a positive effect on the induction of multi-cytokine responses, as well as the increased level of IL-10, showing its higher immunogenicity with a higher immunoregulatory mechanism.


Asunto(s)
Vacunas contra el SIDA/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Compuestos de Alumbre/administración & dosificación , Infecciones por VIH/inmunología , Infecciones por VIH/prevención & control , Naloxona/inmunología , Vacunas contra el SIDA/administración & dosificación , Vacunas contra el SIDA/química , Compuestos de Alumbre/química , Animales , Anticuerpos Antivirales/inmunología , Composición de Medicamentos , Femenino , Infecciones por VIH/virología , VIH-1/inmunología , Humanos , Inmunización , Interferón gamma/genética , Interferón gamma/inmunología , Interleucinas/genética , Interleucinas/inmunología , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Naloxona/administración & dosificación , Naloxona/química
18.
Probiotics Antimicrob Proteins ; 13(6): 1539-1545, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33843030

RESUMEN

Regulation of immune responses is among the beneficial effects of probiotic bacteria on human health. In this study, we aim to investigate the effect of normal and heat-shocked Lactobacillus plantarum PTCC 1058 cell lysate on cytokine expression by human PBMCs. The mid-exponential phase L. plantarum (108 CFU/mL) were used to prepare cell lysate. Isolated PBMCs were stimulated with 100 µg/mL of each normal and heat-shocked L. plantarum cell lysate for 72 h. Non-stimulated PBMCs were also evaluated as negative control. The mRNA expression of IL-6, IL-10, IFN-É£, TNF-α, and TGF-ß genes was determined by quantitative RT-PCR amplification of total RNA extracted from PBMCs. Both types of cell lysate were able to increase pro-inflammatory cytokines and decrease anti-inflammatory cytokines. However, this effect was significantly stronger in heat-shocked cell lysate-treated PBMCs. Moreover, comparison of IFN-É£/IL-10, IFN-É£/TGF-ß, IL-6/IL-10, IL-6/TGF-ß, and TNF-α/IL-10 ratios in both conditions demonstrated that in the heat-shocked group, all of the above ratios were significantly higher than normal lysate treatment (p˂0.001), suggesting that heat-shocked probiotics are a potent inducer of the immune system in comparison to intact probiotics. Regarding these results, it may be possible to develop a new postbiotic product for the stimulation of immune responses of cancer patients or individuals who suffer from an immune defect.


Asunto(s)
Citocinas/metabolismo , Lactobacillus plantarum , Leucocitos Mononucleares/inmunología , Células Cultivadas , Calor , Humanos , Interleucina-10 , Interleucina-6 , Factor de Crecimiento Transformador beta , Factor de Necrosis Tumoral alfa
19.
Carbohydr Polym ; 254: 117262, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33357850

RESUMEN

A novel theranostic nanoplatform was prepared based on Fe3O4 nanoparticles (NPs) coated with gadolinium ions decorated-polycyclodextrin (PCD) layer (Fe3O4@PCD-Gd) and employed for Curcumin (CUR) loading. The dissolution profile of CUR indicated a pH sensitive release manner. Fe3O4@PCD-Gd NPs exhibited no significant toxicity against both normal and cancerous cell lines (MCF 10A and 4T1, respectively); while the CUR-free NPs showed more toxicity against 4T1 than MCF 10A cells. In vivo anticancer study revealed appropriate capability of the system in tumor shrinking with no tissue toxicity and adverse effect on body weight. In vivo MR imaging of BALB/c mouse showed both T1 and T2 contrast enhancement on the tumor cells. Fe3O4@PCD-Gd/CUR NPs showed significant features as a promising multifunctional system having appropriate T1-T2 dual contrast enhancement and therapeutic efficacy in cancer theranostics.


Asunto(s)
Celulosa , Ciclodextrinas , Gadolinio , Nanopartículas Magnéticas de Óxido de Hierro , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/tratamiento farmacológico , Nanomedicina Teranóstica/métodos , Animales , Antineoplásicos/administración & dosificación , Materiales Biocompatibles/química , Materiales Biocompatibles/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Quelantes , Medios de Contraste , Curcumina/administración & dosificación , Sistemas de Liberación de Medicamentos , Hemólisis/efectos de los fármacos , Humanos , Técnicas In Vitro , Nanopartículas Magnéticas de Óxido de Hierro/química , Nanopartículas Magnéticas de Óxido de Hierro/toxicidad , Nanopartículas Magnéticas de Óxido de Hierro/ultraestructura , Imagen por Resonancia Magnética , Magnetismo , Masculino , Ensayo de Materiales , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica de Rastreo , Neoplasias Experimentales/patología , Medicina de Precisión , Espectroscopía Infrarroja por Transformada de Fourier
20.
Avicenna J Med Biotechnol ; 13(4): 201-206, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34900146

RESUMEN

BACKGROUND: The inhibitory effect of selenium nanoparticles (SeNPs) on cancer cells has been reported in many studies. In this study, the purpose was to compare the in vitro effects of SeNPs and calcium sulfate coated selenium nanoparticles (CaSO4@SeNPs) on breast cancer cells. METHODS: CaSO4@SeNPs and SeNPs were chemically synthesized and characterized with Field Emission Scanning Electron Microscope (FESEM) and energy-dispersive X-ray spectroscopy (EDX). By applying MTT assay, the cytotoxicity effect of both nanomaterials on the 4T1 cancer cells was investigated. RESULTS: While LD50 of SeNPs on 4T1 cancer cells was 80 µg, the LD50 of CaSO4@SeNPs was reported to be only 15 µg. The difference between the inhibition rates obtained for SeNPs and CaSO4@SeNPs was statistically significant (p=0.05). In addition, at higher concentrations (50 µg) of CaSO4@SeNPs, the cytotoxicity was 100% more than SeNPs alone. CONCLUSION: According to the result of the present work, it can be concluded that decoration of SeNPs with calcium sulfate leads to an increase in potency by decreasing the effective dose. This effect can be attributed to activation of intrinsic apoptosis signaling and/or pH regulatory properties of CaSO4@SeNPs. However, further studies are still needed to determine the exact corresponding mechanisms of this synergistic effect.

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