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1.
Viral Immunol ; 35(3): 244-253, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35467429

RESUMO

Declined immune response is the main cause of decreased potency of the influenza vaccine in the elderly, regardless of virus mutations. Herein, we hypothesized that the addition of α-tocopherol to the influenza vaccine formulation might increase vaccine potency and efficacy. Hemagglutinin of the H1N1 virus was formulated in Alum and α-tocopherol, and then aged (16-20-month-old) and young (6-8-week-old) mice were immunized subcutaneously two times with 2-week intervals with 5 µg of different vaccine formulations. Two weeks after the final boosting, IFN-γ and IL-4 cytokines were assessed by using ELISA. Humoral immune responses were assessed by hemagglutination inhibition (HI). In addition, vaccine efficacy was determined by intranasal viral challenge of mice using mouse-adapted H1N1 virus. Our results showed that the new vaccine formulation improved IFN-γ and IL-4 responses in the experimental mice. However, the increase was evident mainly in the aged group and, to some extent, in the young group. Results from the HI assay showed that α-tocopherol in the vaccine formulation could increase HI activity in both young and aged mice. Furthermore, α-tocopherol, as an adjuvant, increased the protectivity of the influenza vaccine in both aged and young groups through the decreased lung viral load and increased survival rate of the experimental mice. In conclusion, it seems that α-tocopherol can not only be used as an appropriate adjuvant for aged people, but also empower old and worn out cells to increase the effectiveness of the vaccine in the elderly.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Adjuvantes Imunológicos , Idoso , Animais , Humanos , Imunidade Humoral , Influenza Humana/prevenção & controle , Interleucina-4 , Camundongos , Camundongos Endogâmicos BALB C , alfa-Tocoferol
2.
Viral Immunol ; 35(2): 150-158, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35319970

RESUMO

New strategies to increase the immune response to HIV-1 vaccine using immunological adjuvants such as Toll-like receptor agonists are needed. In this study, HIV-1 p24-Nef and conjugated form of the vaccine candidate to type-A flagellin (FLA) were injected in the BALB/c mice in different routes. Two weeks after the last immunization, lymphocyte proliferation was measured by the BrdU method. The IL-4 and IFN-γ levels, as well as the total IgG antibody and its isotypes titer, were evaluated by the enzyme-linked immunosorbent assay method. The IFN-γ ELISPOT was also performed. Our data showed that the HIV-1 p24-Nef alone and conjugated to type-A flagellin (FLA) significantly increased lymphocyte proliferation responses as well as higher levels of cytokines and IFN-γ producing lymphocytes and the level of humoral immune responses compared with the control groups. The cell-mediated immune responses through the subcutaneous route and humoral immune responses through the intramuscular route were significantly higher in the conjugated form than in the mere vaccine candidate. In conclusion, when the FLA as an adjuvant is constructed in the HIV-1 vaccine candidate, it could effectively improve both humoral and cellular immune responses. Furthermore, modification in the vaccine formulation could change the optimal route of vaccine inoculation.


Assuntos
Vacinas contra a AIDS , HIV-1 , Adjuvantes Imunológicos , Animais , Flagelina , Proteína do Núcleo p24 do HIV , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Pseudomonas aeruginosa
3.
Vaccines (Basel) ; 10(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35214658

RESUMO

Staphylococcus aureus (S. aureus) is an opportunistic pathogen that causes various inflammatory local infections, from those of the skin to postinfectious glomerulonephritis. These infections could result in serious threats, putting the life of the patient in danger. Antibiotic-resistant S. aureus could lead to dramatic increases in human mortality. Antibiotic resistance would explicate the failure of current antibiotic therapies. So, it is obvious that an effective vaccine against S. aureus infections would significantly reduce costs related to care in hospitals. Bacterial vaccines have important impacts on morbidity and mortality caused by several common pathogens, however, a prophylactic vaccine against staphylococci has not yet been produced. During the last decades, the efforts to develop an S. aureus vaccine have faced two major failures in clinical trials. New strategies for vaccine development against S. aureus has supported the use of multiple antigens, the inclusion of adjuvants, and the focus on various virulence mechanisms. We aimed to present a compressive review of different antigens of S. aureus and also to introduce vaccine candidates undergoing clinical trials, from which can help us to choose a suitable and effective candidate for vaccine development against S. aureus.

4.
Microb Pathog ; 160: 105184, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34508828

RESUMO

Hepatitis B virus (HBV) infection is limited through vaccination against HBsAg formulated in the Alum adjuvant. However, this alum-formulated vaccine fails to be preventive in some cases, also known as non-responders. Recent studies have shown the immunomodulatory effect of α-tocopherol in various models. Here, we developed a new formulation for HBsAg using α-tocopherol, followed by assessment of immune responses. Experimental BALB/c mice were immunized with a commercial alum-based vaccine or the one formulated in α-tocopherol at different doses. Mice were immunized subcutaneously with 5 µg of HBsAg with different formulations three times with 2-week intervals. Specific total IgG, IgG1, and IgG2a isotypes of antibodies were measured by ELISA. Immunologic cytokines, such as IFN-γ, IL-4, IL-2, and TNF-α, were also evaluated through commercial ELISA kits. Our results showed that the new α-tocopherol-formulated vaccine had the ability to reinforce specific total IgG responses. Moreover, α-tocopherol in the HBsAg vaccine increased IFN-γ, IL-2, and TNF-α cytokines at higher concentrations; however, the vaccine suppressed IL-4 cytokine release. At a lower concentration of α-tocopherol, the IL-4 cytokine response increased without a positive effect on IFN-γ and TNF-α cytokine response. It seems that α-tocopherol can change the immune responses against HBsAg; however, the type of response depends on the dose of α-tocopherol used in the vaccine formulation.


Assuntos
Citocinas , Vacinas contra Hepatite B , Interferon gama/imunologia , Adjuvantes Imunológicos , Animais , Citocinas/imunologia , Anticorpos Anti-Hepatite B , Vacinas contra Hepatite B/imunologia , Camundongos , Camundongos Endogâmicos BALB C
5.
Iran J Basic Med Sci ; 24(4): 545-550, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34094038

RESUMO

OBJECTIVES: Though immunization with HBsAg has been routine since the 1980s, it has numerous limitations such as low or none humoral immune responses. Today, nanotechnology is used in vaccinology to achieve higher potency. The present study deals with the achievement of fast antibody response of humoral immune responses using immune-targeting through mannosylated nanocarriers of the vaccine. MATERIALS AND METHODS: Mannose sugar and HBsAg were attached to the surface of iron oxide nanoparticles. Mannosylated iron oxide nanoparticles conjugated HBsAg (HBsAg +MLCMNP), iron oxide nanoparticles conjugated HBsAg (HBsAg +LCMNP), hepatitis B vaccine, and mere HBsAg were injected twice to BALB/c mice subcutaneously, while suitable control groups were considered. Specific total IgG antibodies were evaluated on the 7th and 14th days after the final immunization. The avidity maturation of the humoral immune response was assessed with an optimized ELISA. Graph pad prism software was used to analyze statistical data. RESULTS: Results showed that on the seventh day of the final shooting, the mannosylated nano-vaccine caused higher antibody response induction than nano-vaccine without mannose and commercial vaccine groups. After 14 days of the second injection, a significant difference was seen versus the nano-vaccine without mannose but not the commercial vaccine group. In addition, the avidity index in mannosylated nano-vaccine showed a significant increase compared with the nano-vaccine without mannose and mere HBsAg group but not compared with the commercial vaccine. CONCLUSION: It seems that mannosylated nano-vaccine has more potency to achieve fast antibody responses and also higher quality of humoral immune response.

6.
Microb Pathog ; 157: 104953, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34044042

RESUMO

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.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Vacinas , Animais , Clonagem Molecular , Staphylococcus aureus Resistente à Meticilina/genética , Camundongos , Camundongos Endogâmicos BALB C , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/genética
7.
Int Immunopharmacol ; 96: 107599, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33848910

RESUMO

Montanide ISA 51VG adjuvant has been approved for human clinical application and stimulates cellular and humoral immune responses. Here, HBsAg was formulated in Montanide ISA51VG adjuvant to compare its potency with the Fendrix and HBsAg-alum vaccines. In particular, the long-term humoral response was assessed up to 220 days after the final immunization. BALB/c mice were allocated into six groups. Treatment groups were injected with HBsAg-Montanide ISA51VG, the Fendrix and commercial HBsAg-alum, respectively. Montanide ISA51 VG, Alum and PBS injected mice were considered as control groups. Mice were immunized three times with 2-week intervals on days 0, 14 and 28 by subcutaneous injection. Lymphocyte proliferation was assessed with the BrdU method. IFN-γ, IL-2 and IL-4 cytokines, specific total IgG and IgG1/IgG2a isotypes were assessed using ELISA. The HBsAg-Montanide ISA51VG vaccine resulted in a significant increase in lymphocyte proliferation versus HBsAg-alum and higher IL-2 cytokine production versus the Fendrix. Comparable IL-4 and IFN-γ cytokines responses were observed for these vaccines. Following the first immunization, IgG increased more in HBs-Montanide 51VG group versus the HBs-alum group, while after the second and third shots comparable responses were observed in comparison to the HBs-alum group. Monitoring for 220 days after the final vaccination showed the superiority of HBsAg-Montanide ISA 51VG vaccine versus HBsAg-alum and even the Fendrix vaccine in the induction of long-term antibody responses. This study suggests that HBsAg-Montanide ISA51VG as a novel vaccine formulation can trigger both cellular and long-lasting humoral immune responses more efficiently than conventional HBsAg vaccines.


Assuntos
Composição de Medicamentos/métodos , Antígenos de Superfície da Hepatite B/imunologia , Imunidade Humoral/imunologia , Manitol/análogos & derivados , Ácidos Oleicos/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Formação de Anticorpos/efeitos dos fármacos , Citocinas/metabolismo , Feminino , Antígenos de Superfície da Hepatite B/administração & dosagem , Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/imunologia , Imunoglobulina G/sangue , Injeções Subcutâneas , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Manitol/administração & dosagem , Manitol/imunologia , Camundongos Endogâmicos BALB C , Ácidos Oleicos/administração & dosagem , Tempo
8.
Probiotics Antimicrob Proteins ; 13(6): 1539-1545, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33843030

RESUMO

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.


Assuntos
Citocinas/metabolismo , Lactobacillus plantarum , Leucócitos Mononucleares/imunologia , Células Cultivadas , Temperatura Alta , Humanos , Interleucina-10 , Interleucina-6 , Fator de Crescimento Transformador beta , Fator de Necrose Tumoral alfa
9.
APMIS ; 129(8): 480-488, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33539574

RESUMO

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.


Assuntos
Vacinas contra a AIDS/imunologia , Adjuvantes Imunológicos/administração & dosagem , Compostos de Alúmen/administração & dosagem , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Naloxona/imunologia , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/química , Compostos de Alúmen/química , Animais , Anticorpos Antivirais/imunologia , Composição de Medicamentos , Feminino , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Imunização , Interferon gama/genética , Interferon gama/imunologia , Interleucinas/genética , Interleucinas/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Naloxona/administração & dosagem , Naloxona/química
10.
Microb Pathog ; 150: 104656, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33253858

RESUMO

Staphylococcus aureus is a powerful pathogen that causes a wide range of infectious diseases and results in a high mortality rate in humans. Treating S. aureus-related infections is extremely difficult because of its ability to resist many antibiotics; therefore, developing an effective vaccine against this infection can be an alternative and promising approach. In this study, we evaluated the protective effects of a Hla-MntC-SACOL0723 multi-epitope protein (HMS) compared with HMS conjugated to polysaccharides 5 and 8 (CP5 and CP8) of S. aureus and CP5 and CP8 in a mouse sepsis model. To evaluate the type of induced immune response, specific IgG, and antibody isotypes (IgG1 and IgG2a) were determined using the ELISA method. The functional activity of these vaccine candidates was assessed by opsonophagocytosis. Mice were infected with S. aureus COL strain and evaluated for bacterial load in the kidney and spleen homogenates. Th1, Th2, and Th17-related cytokines in the spleen cell supernatants were assessed by flow cytometry. The therapeutic effect of specific anti-HMS protein IgG antibodies against S. aureus COL strain infection was evaluated by passive immunization. HMS recombinant protein induced a higher level of Th1, Th2, and Th17-related cytokines compared with conjugated molecules. Also, mice immunized with the HMS protein reduced the bacterial load in the kidney and spleen more than the one that received the conjugated molecules. Our study suggests that the HMS fusion protein and conjugate molecule vaccine candidates could be suitable candidates for the removal of S. aureus in the mouse sepsis model but HMS protein can be a more effective candidate.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Animais , Anticorpos Antibacterianos , Imunidade , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes , Infecções Estafilocócicas/prevenção & controle , Vacinas Conjugadas
11.
Iran J Basic Med Sci ; 24(11): 1546-1553, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35317113

RESUMO

Objectives: Influenza is a highly contagious disease, which affects the respiratory system and seasonal influenza is common throughout the world. Influenza vaccination is an effective way to reduce the risk of death and hospitalization. This study aims at the expression of swine recombinant hemagglutinin protein in the baculovirus expression system and it offers a comparison of the immunologic parameters with the commercial vaccine. Materials and Methods: The HA gene from the swine H1N1 strain of the Influenza virus was cloned into the Bac-To-Bac expression system in pFastBAC HTA vector and was transformed into Escherichia coli TOP10 strain. After the confirmation, the vector was transfected into the SF9 insect cell line. The recombinant HA was evaluated by SDS-PAGE and western blot. After formulation in Montanide ISA71 adjuvant, the immunization test was performed comparatively with Alum adjuvant, commercial vaccine in four groups of BALB/c mice, of which one group was control without any vaccination. Two weeks after the last immunization, the antibody response was assessed with HI assay, and experimental mice were challenged with mouse-adapted Influenza A/PR8/34 (H1N1) virus through nasal inhalation. Results: The immunoassay results revealed that the candidate vaccine induced the antibody response as the commercial one did but it did not significantly reduce the mortality rate, body loss, and severe fever. Conclusion: To summarize, the results showed that the recombinant protein with the MontanideTM ISA- 71 adjuvant developed a more appropriate level of immunity than Alum adjuvant, so it might be used as a safe and reliable vaccine against H1N1 virus for further research.

12.
Mol Immunol ; 124: 70-82, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32540517

RESUMO

Several vaccine candidates have been introduced for immunization against Pseudomonas aeruginosa strains. Despite extensive efforts in recent decades, there is no accurate immunogenic candidate against this pathogen in the market yet. Due to the rapid increase in several drug-resistant strains, P. aeruginosa has caused various health concerns worldwide. It encodes many specific virulence features, which can be used as an appropriate vaccine candidate. The primary stage of the pathogenesis of P. aeruginosa is the expression of many dynamic adhesive molecules, such as type IV pili (T4P), which acts as a principal colonization factor. It has been confirmed that three different subtypes of T4P, including type IVa (T4aP), type IVb (T4bP) and tight adherence (Tad) pili are expressed by P. aeruginosa. The IVa fimbriae type is almost the main cause of challenges to design an effective pili based-immunotherapy method. Nevertheless, in terms of heterogeneity, variability and hidden conserved binding site of T4aP, this attitude has been remained controversial and there is no permitted human study based on IVa pilin commercially. The engineered synthetic peptide-based vaccines are highly talented to mimic the target. In this research, for the first time, some dominant immunogenic features of the Flp protein, such as both B- and T-cell-associated epitopes, presence of IgE-associated epitopes, solvent-accessible surface area were evaluated by analytical immunoinformatics methods. In addition, we designed the engineered Flp pilin as an effective immunogenic substance against several clinically important P. aeruginosa strains. Moreover, by practical active immunization approaches, the humoral and cellular immune response against the extremely conserved region of the engineered synthetic Flp (EFlp) formulated in Montanide ISA 266 compared to the control group. The results of active immunization against EFlp significantly signified that EFlp-Montanide ISA 266 (EFLP-M) strongly could induce both humoral and cellular immune responses. We concluded that Flp pilin has therapeutic potential against numerous clinically significant P. aeruginosa strains and can be served as a novel immunogen for further investigations for development of effective immunotherapy methods against P. aeruginosa as a dexterous pathogen.


Assuntos
Proteínas de Bactérias/imunologia , Vacinas contra Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Animais , Biologia Computacional , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Feminino , Epitopos Imunodominantes/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Pseudomonas/prevenção & controle , Vacinação , Vacinas Sintéticas/imunologia
13.
Iran J Immunol ; 17(1): 75-86, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32224543

RESUMO

BACKGROUND: Pseudomonas aeruginosa has an important role in nosocomial infections. OBJECTIVE: To evaluate biological activity of the detoxified LPS (D-LPS) entrapped into Poly lactic-co-glycolic acid (PLGA) nanoparticles. MATERIALS: LPS was extracted and detoxified from the P. aeruginosa strain PAO1. The D-LPS, conjugated to the PLGA nanoparticles with 1-ethyl-3-dimethyl aminopropyl carbodiimide (EDAC) and N-hydroxy-succinimide (NHS). The connection was evaluated by FTIR (Fourier transform infrared), Zetasizer, and Atomic Force Microscope (AFM). The BALB/c mice injected intramuscularly with the D-LPS-PLGA with two-week intervals and then challenged two weeks after the last immunization. The bioactivity of the induced specific antisera and cytokines responses against D-LPS-PLGA antigen was assessed by ELISA. RESULTS: D-LPS-PLGA conjugation was confirmed by FTIR, Zetasizer, and AFM. The ELISA results showed that D-LPS was successful in the stimulation of the humoral immune response. The immune responses raised against the D-LPS-PLGA, significantly decreased bacterial titer in the spleen of the immunized mice after challenge with PAO1 strain in comparison with the control groups. CONCLUSION: The conjugation of the bacterial LPS to the PLGA nanoparticle increased their functional activity by decrease in bacterial dissemination and increase the killing of opsonized bacteria.


Assuntos
Antígenos de Bactérias , Lipopolissacarídeos , Nanopartículas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Vacinas contra Pseudomonas , Animais , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/farmacologia , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Vacinas contra Pseudomonas/imunologia , Pseudomonas aeruginosa
14.
Iran J Allergy Asthma Immunol ; 19(5): 497-508, 2020 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-33463117

RESUMO

The H1N1 influenza virus is known as a serious pandemic threat across the globe. Vaccination is one of the most effective methods of protection against this virus and the way to reduce the seasonal pandemic risk. The commercial vaccine does not adequately respond to pandemic strains. This study examines the potential function of formulated H1N1 hemagglutinin with MF59 adjuvant against A/PR/8/34 (H1N1). To this end, a recombinant hemagglutinin (rHA) gene of influenza A virus was designed and expressed in SF9 cell by the Baculovirus expression system. Four groups of mice were immunized by rHA in combination with MF59, Alum adjuvant, and virus split only. The immunized mice subsequently used for the humoral immune assay and the results compared with untreated mice (negative group). Besides, both treated and control mice groups were challenged with mouse-adapted influenza virus A/PR/8/34(H1N1) through the intranasal drop. Bodyweight, survival, temperature variation, and the medical conditions of the samples were assessed. Mice immunized with the recombinant protein demonstrated a humoral response to the influenza A virus. Upon virus challenging, co-administration of rHA with MF59 adjuvant could lead to 92% survival of the vaccinated mice within 10 days. The MF59-treated group showed slight weight loss and high-temperature body two weeks after infection. This group also displayed a higher hemagglutination inhibition (HI) antibody titer as compared to the group vaccinated with virus split, and Alum adjuvant. Altogether, the results showed that the recombinant protein with the MF59 adjuvant created better safety than the Alum adjuvant, thereby can be considered as a safe and reliable vaccine against the H1N1 virus for further investigations.


Assuntos
Hemaglutininas/imunologia , Imunidade/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/imunologia , Esqualeno/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Antivirais/imunologia , Linhagem Celular , Modelos Animais de Doenças , Feminino , Testes de Inibição da Hemaglutinação/métodos , Camundongos , Camundongos Endogâmicos BALB C , Polissorbatos , Células Sf9 , Vacinação/métodos
15.
Microb Pathog ; 140: 103945, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31874228

RESUMO

Staphylococcus aureus is an important cause of both hospital and community acquired infections worldwide. S.aureus can develop multidrug resistance; thus, immunotherapy can be a rational alternative. High level ß-lactam resistance of S. aureus has been attributed to the penicillin binding protein 2a (PBP2a). In this study, we assessed the immunogenicity and protectivity of PBP2a formulated in Montanide ISA266 and Alum adjuvants. Recombinant PBP2a with a molecular weight of approximately 13 kDa was expressed and purified by nickel-nitrilotriacetic acid (NI-NTA) affinity chromatography and characterized by SDS-PAGE and Western blot. To investigate the immunogenicity and protective effects of recombinant protein, 20 µg of r-PBP2a in various formulations were subcutaneously injected in different groups. Two booster vaccinations were carried out in two-week intervals and blood samples were collected two weeks after each injection. To determine the type of induced immune response, sera and splenocytes were analyzed by ELISA for total IgG and isotypes (IgG1 and IgG2a) and cytokine secretion (IFN-γ, IL-4, IL-17 and TNF-α), respectively. Three weeks following the last immunization, experimental mice were challenged with 5 × 108 CFU of bacteria intraperitoneally and mortality rate and bacterial load were assessed. Interestingly, analysis of humoral immune responses revealed that administration of r-PBP2a with Montanide ISA266 significantly increased specific IgG responses and also IgG1 isotype compared to alum-adjuvanted vaccine group. Also, r-PBP2a formulation with alum and MontanideISA266 adjuvants raised IFN-γ, IL-4, IL-17 cytokines secretion, and protectivity following experimental challenge. The results of the present study provide evidences for immunogenicity and protectivity of PBP2a protein as a vaccine candidate.


Assuntos
Adjuvantes Farmacêuticos/administração & dosagem , Proteínas de Bactérias/administração & dosagem , Staphylococcus aureus Resistente à Meticilina/imunologia , Proteínas de Ligação às Penicilinas/administração & dosagem , Infecções Estafilocócicas/imunologia , Adjuvantes Farmacêuticos/análise , Compostos de Alúmen/administração & dosagem , Compostos de Alúmen/análise , Animais , Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Composição de Medicamentos , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunoglobulina G/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-4/genética , Interleucina-4/imunologia , Manitol/administração & dosagem , Manitol/agonistas , Staphylococcus aureus Resistente à Meticilina/genética , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Ligação às Penicilinas/genética , Proteínas de Ligação às Penicilinas/imunologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle
16.
Microb Pathog ; 140: 103932, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31857237

RESUMO

Today's, vaccination is the most cost-effective approaches for preventing infectious diseases. In this strategy, adjuvants play an important role. Propolis from honey bee can stimulate the immune system and several studies have shown the modulating effects of Propolis on the immune responses. Here, the adjuvant effects of aqueous and alcoholic extracts of Propolis were studied on the multi-epitope vaccines against HIV-1. A recombinant vaccine against HIV-1 was prepared and BALB/c mice were immunized. subcutaneously on day 0 with 100 µl of candidate vaccine (10 µg) formulated in an alcoholic extract of Propolis. The second group of mice was immunized with the vaccine (10 µg) formulated in aqueous extract of Propolis. Also, candidate vaccine was formulated in Freund's and Alum adjuvants in the third and fourth groups. Experimental mice were immunized three times with two week intervals under the same conditions and suitable control groups. After final injection, lymphocyte proliferation was measured by BrdU method, IL-4 and IFN-γ cytokines, specific total IgG antibodies, IgG1 and IgG2a isotypes were evaluated using ELISA. The results show that the aqueous and alcoholic extracts were able to enhance lymphocyte proliferation, IL-4 and IFN-γ cytokines and antibody responses with dominant IgG1 pattern and comparable to Freund's and Alum adjuvants. It seems that aqueous and alcoholic extracts of Propolis show adjuvant activity and may be useful for vaccine formulation.


Assuntos
Adjuvantes Imunológicos/farmacologia , HIV-1/imunologia , Própole/farmacologia , Compostos de Alúmen/farmacologia , Animais , Formação de Anticorpos/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Adjuvante de Freund/farmacologia , Imunidade Celular/efeitos dos fármacos , Imunoglobulina G/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Vacinas Sintéticas/imunologia
17.
Immunol Invest ; 49(8): 875-896, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31856615

RESUMO

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.


Assuntos
Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/terapia , Controle de Infecções , Anticorpos de Domínio Único/farmacologia , Anticorpos de Domínio Único/uso terapêutico , Gerenciamento Clínico , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Humanos , Controle de Infecções/métodos , Anticorpos de Domínio Único/imunologia , Resultado do Tratamento
18.
IUBMB Life ; 72(2): 226-236, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31573748

RESUMO

Staphylococcus aureus is one of the most common pathogens in the hospital and the community. The emergence of broad-spectrum antibiotic resistance in S. aureus has made the treatment process more difficult. Therefore, it is obvious that an effective prevention strategy against the pathogen could significantly reduce costs related to care in hospitals. In this report, we describe a simple approach to conjugate S. aureus capsular polysaccharide 5 (CP5) from S. aureus Reynolds strain and 8 (CP8) from S. aureus Becker strain to a fusion protein (Hla-MntC-SACOL0723) and investigation of its bioactivity. The conjugation was done by using ADH (as a bridge) and EDAC (as a coupling agent). The immunoconjugates were characterized by routine polysaccharide/protein contents assays followed by reverse phase chromatography and FTIR spectroscopy. The groups of mice were immunized with conjugate vaccines, capsular polysaccharides, and phosphate-buffered saline (PBS) as a control group. The functional activity of the vaccine candidates was evaluated by ELISA, opsonophagocytosis tests, and determination of bacterial load in challenge study. The results showed that the specific antibody (total IgG) titers raised against conjugate molecules were higher than those of the nonconjugated capsular polysaccharides. The opsonic activity of the conjugate vaccines antisera was significantly higher than polysaccharides alone (58% reduction in the number of bacteria versus 16.3% at 1:2 dilution, p < .05), Further, the conjugate vaccine group had a significant reduction in bacterial load after challenge with S. aureus COL strain cells as compared to the PBS and nonconjugated controls. In conclusion, the immunoconjugates could be developed as a potential vaccine candidate against S. aureus.


Assuntos
Cápsulas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Imunoconjugados/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/imunologia , Vacinas Conjugadas/administração & dosagem , Animais , Anticorpos Antibacterianos , Feminino , Imunoconjugados/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Coelhos , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Vacinas Conjugadas/imunologia
19.
Curr Drug Discov Technol ; 17(2): 225-232, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30417790

RESUMO

OBJECTIVE: This investigation evaluates the pro-apoptotic and anti-inflammatory effects of ß-D-mannuronic acid [M2000] compared to diclofenac, based on gene expression involved in apoptosis and inflammation process [including Bcl2, NFκB, IL-8 and Cd49d] in Peripheral Blood Mononuclear Cells [PBMCs] of healthy donors under exvivo conditions. MATERIALS: The venous blood samples of twelve healthy volunteers with aged 25-60 years were collected in heparinized tubes. The healthy volunteers were selected from no smoking group and without using illicit drugs and suffering from diabetes. The PBMCs were separated and divided into untreated and treated groups. METHODS: The PBMCs of each sample were cultured in 5 wells of culture plate, so that the first well consisted of 2×106 cells exposed by LPS-EB [1µg/ml] to stimulate PBMCs and absence of M2000 [untreated well]. The second, third, fourth and fifth wells containing 2×106 cells/well and LPS-EB, after 4 hours incubation at 37ºC, received 5, 25 and 50 µg/well of M2000 and 5 µg/well of diclofenac, respectively as treated group. RESULTS: The PBMCs were separated and RNAs were then extracted and cDNAs synthesized and gene expression levels were assessed by qRT-PCR. Furthermore, we studied whether M2000 is able to facilitate apoptosis in PBMCs. Our findings represent that the high dose of M2000 could significantly decrease the expression level of NFκB gene compared to untreated group (p < 0.0002). On the other hand, no significant change was observed in treated cells with diclofenac. All doses of M2000 could significantly augment apoptosis compared to untreated group [p < 0.0001]. Additionally, we observed the same apoptotic effects between the medium dose of M2000 and diclofenac. Besides, no significant reduction was shown in expression levels of IL8, Bcl2 and Cd49d genes in all doses of M2000 and diclofenac compared to untreated group. This experiment demonstrates M2000 as a new effective NSAID with immunosuppressive characteristics capable of stimulating apoptosis through lowering expression levels of NFκB gene, which might be probably considered as an appropriate drug for reducing the risk of developing inflammatory diseases and cancer.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/efeitos dos fármacos , Ácidos Hexurônicos/farmacologia , Imunossupressores/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Apoptose/genética , Apoptose/imunologia , Diclofenaco/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Voluntários Saudáveis , Ácidos Hexurônicos/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/imunologia , Integrina alfa4/metabolismo , Interleucina-8/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Adulto Jovem
20.
Gastroenterol Hepatol Bed Bench ; 12(4): 292-300, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31749917

RESUMO

Aim: In the present study, a new formulation of HBsAg vaccine was developed and compared with a commercial peer. Background: Vaccination of hepatitis B infection has been an unavoidable affair since the 1980s, though it has numerous limitations such as inefficacy in the induction of cellular immune responses. To address these limitations, research on novel formulations is necessary to develop a superior formulation with the potency of induction of both cellular and humoral immune responses. Methods: HBsAg was formulated in oil-in-water adjuvant Montanide ISA-266 (5 µg/dose) using homogenizer. Balb/C mice were then immunized three times at days 0, 14, and 28 with HBsAg/Montanide ISA-266 or HBsAg/alum with proper control groups. Two weeks after the last immunization, immunological parameters including IL-2, IL-4, TNF-α, IFN-γ, total IgG and IgG1/IgG2a isotypes were assessed by ELISA. Results: The results demonstrated that the formulation of HBsAg with Montanide ISA-266 enhanced humoral immune responses versus the commercial vaccine and control groups. No significant difference in terms of Th1 pattern was found between HBsAg/Montanide ISA-266 and the commercial vaccine. Conclusion: Formulation of HBsAg with an oil-based adjuvant may be useful for the induction of a more potent humoral immune response compared to the commercially available HBV vaccine.

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