Yazar "Abamor, Emrah Sefik" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • Küçük Resim
    Öğe
    Evaluation Of İn Vitro And İn Vivo İmmunostimulatory Activities Of Poly (Lactic-Co-Glycolic Acid) Nanoparticles Loaded With Soluble And Autoclaved Leishmania İnfantum Antigens: A Novel Vaccine Candidate Against Visceral Leishmaniasis
    (Wolters Kluwer, 2019) Abamor, Emrah Sefik; Allahverdiyev, Adil; Tosyalı, Özlem Ayşe; Bağırova, Melahat; Acar, Tayfun; Mustafaeva, Zeynep; Derman, Serap
    Objective: To prepare and characterize poly lactic-co-glycolic acid (PLGA) nanoparticles loaded with soluble leishmanial antigen or autoclaved leishmanial antigen and explore in vitro and in vivo immunogenicity of antigen encapsulated nanoparticles. Methods: Water/oil/water double emulsion technique was employed to synthesize PLGA nanoparticles, and scanning electron microscopy, Fourier transform infrared spectroscopy and Zeta-potential measurements were used to identify the characteristics of nanoparticles. Cytotoxicity of synthetized nanoparticles on J774 macrophage were investigated by MTT assays. To determine the in vitro immunostimulatory efficacies of nanoparticles, griess reaction and ELISA was used to measure the amounts of NO and cytokines. During the in vivo analysis, Balb/c mice were immunized with vaccine formulations, and protective properties of nanoparticles were measured by Leishman Donovan unit in the liver following the infection. Cytokine levels in spleens of mice were determined by ELISA. Results: MTT assay showed that neither soluble leishmanial antigen nor autoclaved leishmanial antigen encapsulated anoparticles showed cytotoxicity against J774 macrophage cells. Contrary to free antigens, both autoclaved leishmanial antigen-nanoparticle and soluble leishmanial antigen-nanoparticle formulations led to a 10 and 16-fold increase in NO amounts by macrophages, respectively. Leishman Donovan unit calculations revealed that soluble leishmanial antigen-nanoparticles and autoclaved leishmanial antigen-nanoparticles yielded 52% and 64% protection against visceral leishmaniasis in mouse models. Besides, in vitro and in vivo tests demonstrated that by increasing IFN-? and IL-12 levels and inhibiting IL-4 and IL10 secretions, autoclaved leishmanial antigen-nanoparticles and soluble leishmanial antigennanoparticles triggered Th1 immune response. Conclusions: Both autoclaved leishmanial antigen-nanoparticles and soluble leishmanial antigen-nanoparticles formulations provide exceptional in vitro and in vivo immunostimulatory activities. Hence, PLGA-based antigen delivery systems are recommended as potential vaccine candidates against visceral leishmaniasis
  • Küçük Resim Yok
    Öğe
    Nano-co-delivery of lipophosphoglycan with soluble and autoclaved leishmania antigens into PLGA nanoparticles: Evaluation of in vitro and in vivo immunostimulatory effects against visceral leishmaniasis
    (Elsevier, 2021) Tosyali, Ozlem Ayse; Allahverdiyev, Adil; Bagirova, Melahat; Abamor, Emrah Sefik; Aydogdu, Mehmet; Dinparvar, Sahar; Acar, Tayfun
    The aim of the present study was to encapsulate lipophosphoglycan molecule (LPG) which is one of the most immunogenic antigens of Leishmania parasites into PLGA nanoparticles with autoclaved or soluble leishmanial antigens, characterize synthetized nanoparticles with different methods and evaluate their in vitro/in vivo immunostimulatory activities to develop new vaccine candidates. PLGA nanoparticles including LPG and autoclaved leishmania antigen (ALA) or soluble leishmania antigen (ALA) were synthetized by double emulsion solvent evaporation method. The synthetized nanoparticles were characterized by SEM and Zeta-sizer instruments for determination of size, zeta potentials and polydispersity index (PDI) values. The antigen release profiles and encapsulation efficiencies were determined by UV-Vis spectroscopy. Griess reaction and ELISA tests were used for measurements of produced nitric oxide (NO) and cytokine levels of macrophages and splenocytes treated with nanoparticles. For determination of protective effects of nanoparticles, parasite reduction in livers and spleens of immunized mice were calculated by LDU values post-infection. According to results, (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs possessed the sizes of 253 and 307 nm respectively. Antigen-loaded nanoparticles elevated the released NO amounts from macrophages for 14 and 18-folds in contrast to control. Furthermore, synthetized nanoparticles significantly triggered macrophages to produce excessive levels of IFN-gamma and IL-12 cytokines. Besides it was detected that vaccination of mice with (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs elicited approximately 80% protection from Visceral Leishmaniasis. Furthermore, (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs lead to 10 to 14-folds increase in secreted Th1 cytokine levels from splenocytes than control demonstrating abundantly stimulation of T cell response following to vaccination with nano-vaccine formulations. These results reveal that both (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs have excellent immunostimulatory activities and they are promising nanovaccine formulations for the prevention of leishmaniasis in near future.
  • Küçük Resim Yok
    Öğe
    Polymeric Approach to Adjuvant System in Antibody Production against Leishmaniasis Based on Hybridoma Technology
    (Iranian Scientific Society Medical Entomology, 2022) Yildiz, Asli Pinar Zorba; Koken, Gulnaz Yildirim; Abamor, Emrah Sefik; Bagirova, Melahat; Tosyali, Ozlem Ayse; Kocagoz, Tanil; Allahverdiyev, Adil
    Background: Leishmaniasis is a zoonotic disease, which is one of the serious public health problems in the world. Nowadays, antibody production using hybridoma technology may be a correct approach in terms of sensitivity in the diagnosis of diseases such as leishmaniasis. The aim of this study was investigation of the effectiveness of different adjuvants on polyclonal antibody production against L. tropica based on hybridoma technique.Methods: Accordingly, Freund's adjuvant (1956, M. tuberculosis), as a classic adjuvant in studies, was used comparatively with the non-toxic polymeric based Polyoxidonium adjuvant. All animal immunization procedures were conducted at Bezm-i Alem University Experimental Animal Research Center. The adjuvant response was tested both in the serum sample and in the antibodies produced by the hybridomas. The antibody titers were determined with ELISA.Results: Freund's and Polyoxidonium (PO) group blood titer's increased approximately 5.5 fold compared to control after the 6(th) and 8(th) immunization. Hybridomas produced from mice immunized with PO adjuvant induced only antigen-specific antibody response and did not develop an immune response against the adjuvant.Conclusion: Adjuvant selection is very important in terms of the specificity of antibody responses of cells produced in hybridoma technology. Therefore, PO is recommended as a new adjuvant system in this study.