Relative Hypoxia in Immunized Mice Spleen Macrophages as Indicated by Hypoxia Inducible Factors, Cytoglobin and Peroxisome Proliferator Activated Receptor Gamma Coactivator (PGC)‑1α

Abstract

Introduction: Spleen is the largest lymphatic organ in the body that is responsible for initiating an immune response to antigens, consistof macrophages and lymphocytes. Macrophages are cells that engulf foreign bodies by migration, phagocytosis, O 2 burst, lysosomes fusion, synthesis and secretion of various cytokines which would require enormous amounts of energy. Therefore, macrophages needs of O 2 to increase resulting in hypoxia relative. To overcome this situation, the cell is equipped with a special mechanism which is under the control of HIF. They are highly dependent to O 2 existence to produce energy. This process is important for biochemical adaptation in homeostasis. Macrophages expressing Cygb for supplying O 2 and PGC‑1 for mitochondrial biogenesis in producing energy. This study aims to determine whether the spleen macrophages in mice being immunized intraperitoneally with SRBC increase the expression of HIF, Cygb and PGC‑1α. Method: 24 male BALB/c mice, aged 2 months were immunized by injecting 0.2 ml SRBC 2%. Macrophages were taken from spleen of mice. Expression of mRNA and protein levels of HIF‑1α, HIF‑2α, Cygb, PGC‑1α in macrophages were measured by real time RT‑PCR and ELISA, respectively. Level of O 2 burst were measured with WST Salts. Observations were made at 24, 48, and 72 hours post‑immunization. Results: The ability to oxidize antigen levels (O 2 burst) found higher at 24 hours after immunization. The levels of protein and mRNA expression of HIF‑1α and HIF‑2α showed the highest increase at 24 and 48 hours after immunization. The levels of Cygb protein increased at 48 hours group after immunization while mRNA expression increased at 24 hours after immunization. PGC‑1α protein levels decreased in 24 hours after immunization and then increased gradually. Conclusion: This study shows the expression pattern of several proteins in spleen macrophages of mice that was immunized