Immunoadjuvant Effect of Chitosan Oligosaccharide and Its Feasibility of Being Used as an Adjuvant for Attenuated Live Bacteria Vector Vaccines

• Published in: Sichuan da xue xue bao. Journal of Sichuan University. Yi xue ban 2024-03, Vol.55 (2), p.441-446
• Main Authors: Ou, Qian, Chen, Zhaobin, Tang, Jing, Chen, Mengdie, Zhang, Yunwen, Chen, Zinan, Liu, Qu, Luo, Junrong, Wang, Chuan
• Format: Article
• Language: Chinese
• Subjects: Adjuvants, Immunologic - pharmacology; Animals; Bacterial Vaccines - immunology; Cell Survival - drug effects; Chitosan; Cytokines - metabolism; Macrophages - drug effects; Macrophages - immunology; Macrophages - metabolism; Mice; Oligosaccharides - pharmacology; RAW 264.7 Cells; Vaccines, Attenuated - immunology
• ISSN: 1672-173X
• DOI: 10.12182/20240360207

To study the immunoadjuvant effects of chitosan oligosaccharide (COS), including the immune activation and the triggering of lysosomal escape, and to explore whether COS can be used as an adjuvant for attenuated live bacteria vector vaccines. 1) Mouse macrophages RAW264.7 cells were cultured with COS at 0 mg/mL (the control group) and 0.1-4 mg/mL for 24 h and the effect on cell viability was measured by CCK8 assay. Mouse macrophages RAW264.7 were treated with COS at 0 (the control group), 1, 2, and 4 mg/mL for 24 h. Then, the mRNA expression levels of the cytokines, including , -10, , and 4, were determined by RT-qPCR assay. 2) RAW264.7 cells were treated with 1 mL of PBS containing different components, including calcein at 50 μg/mL, COS at 2 mg/mL, and bafilomycin A1, an inhibitor, at 1 μmol/mL, for culturing. The cells were divided into the Calcein group, Calcein+COS group, and Calcein+COS+Bafilomycin A1 group accordingly. Laser scanning confocal microscopy was used to observe the phagocytosis and the intr