Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

Browse

Search Results

Now showing 1 - 2 of 2
  • Article
    Citation - WoS: 9
    Citation - Scopus: 8
    Astragalus Saponins, Astragaloside Vii and Newly Synthesized Derivatives, Induce Dendritic Cell Maturation and T Cell Activation
    (MDPI, 2023) Yakuboğulları, Nilgün; Çağır, Ali; Bedir, Erdal; Sağ, Duygu
    Astragaloside VII (AST VII), a triterpenic saponin isolated from Astragalus species, shows promise as a vaccine adjuvant, as it supported a balanced Th1/Th2 immune response in previous in vivo studies. However, the underlying mechanisms of its adjuvant activity have not been defined. Here, we investigated the impact of AST VII and its newly synthesized semi-synthetic analogs on human whole blood cells, as well as on mouse bone marrow-derived dendritic cells (BMDCs). Cells were stimulated with AST VII and its derivatives in the presence or absence of LPS or PMA/ionomycin and the secretion of cytokines and the expression of activation markers were analyzed using ELISA and flow cytometry, respectively. AST VII and its analogs increased the production of IL-1β in PMA/ionomycin-stimulated human whole blood cells. In LPS-treated mouse BMDCs, AST VII increased the production of IL-1β and IL-12, and the expression of MHC II, CD86, and CD80. In mixed leukocyte reaction, AST VII and derivatives increased the expression of the activation marker CD44 on mouse CD4+ and CD8+ T cells. In conclusion, AST VII and its derivatives strengthen pro-inflammatory responses and support dendritic cell maturation and T cell activation in vitro. Our results provide insights into the mechanisms of the adjuvant activities of AST VII and its analogs, which will be instrumental to improve their utility as a vaccine adjuvant. © 2023 by the authors.
  • Article
    Citation - WoS: 21
    Citation - Scopus: 21
    Development of Adjuvant Nanocarrier Systems for Seasonal Influenza a (h3n2) Vaccine Based on Astragaloside Vii and Gum Tragacanth (aps)
    (Elsevier, 2019) Yakuboğulları, Nilgün; Genç, Rukan; Coven, Fethiye; Nalbantsoy, Ayşe; Bedir, Erdal
    Adjuvants are chemical/biological substances that are used in vaccines to increase the immunogenicity of antigens. A few adjuvants have been developed for use in human vaccines because of their limitations including lack of efficacy, unacceptable local or systemic toxicity, the difficulty of manufacturing, poor stability, and high cost. For that reasons, novel adjuvants/adjuvant systems are under search. Astragaloside VII (AST-VII), isolated from Astragalus trojanus, exhibited significant cellular and humoral immune responses. The polysaccharides (APS) obtained from the roots of Astragalus species have been used in traditional Chinese medicine and possess strong immunomodulatory properties. In the present study, the immunomodulatory effects of a newly developed nanocarrier system (APNS: APS containing carrier) and its AST-VII containing formulation (ANS: AST-VII + APNS), on seasonal influenza A (H3N2) vaccine were investigated. Inactivated H3N2 alone or its combinations with test compounds/formulations were intramuscularly injected into Swiss albino mice. Four weeks after immunization, the immune responses were evaluated in terms of antibody and cytokine responses as well as splenocyte proliferation. APNS demonstrated Th2 mediated response by increasing IgG1 antibody titers, whereas ANS showed response towards Th1/Th2 balance and Th17 by producing of IFN-gamma, IL-17A and IgG2a. Based on these results, we propose that APNS and ANS are good candidates to be utilized in seasonal influenza A vaccines as adjuvants/carrier systems. (C) 2019 Elsevier Ltd. All rights reserved.