Bordetella bronchiseptica antigen enhances the production of Mycoplasma hyopneumoniae antigen-specific immunoglobulin G in mice
Seol-Hwa Yim1, Tae-Wook Hahn2, Hong-Gu Joo1,*
1College of Veterinary Medicine, Jeju National University, Jeju 63243, Korea 2College of Veterinary Medicine, Kangwon National University, Chuncheon 24341, Korea
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Received: May 4, 2016; Revised: August 5, 2016; Accepted: September 22, 2016; Published online: September 23, 2016.
We previously demonstrated that Bordetella bronchiseptica (B. bronchiseptica) antigen (Ag) showed high immunostimulatory effects on mouse bone marrow cells (BMs) while Mycoplasma hyopneumoniae (M. hyopneumoniae) Ag showed low. The focus of this study was if B. bronchiseptica Ag may enhance M. hyopneumoniae Ag-specific immune response, and also the host immune system can recognize both Ags. MTT assay revealed that each or both Ags did not significantly change the cell metabolic activity of BMs. Flow cytometry analysis using carboxyfluorescein succinimidyl ester presented that B. bronchiseptica Ag can promote the cell division of BMs. In cytokine and nitric oxide (NO) assays, B. bronchiseptica Ag can boost the production of tumor necrosis factor-alpha in M. hyopneumoniae Ag-treated BMs and the combined treatment of both Ags elevated the level of NO in BMs compared to the treatment of M. hyopneumoniae Ag alone. Immunoglobulin (Ig)G ELISA using the sera of Ag-injected mice clearly indicated that B. bronchiseptica Ag can increase the production of M. hyopneumoniae Ag-specific IgG. This study provides valuable information to develop M. hyopneumoniae vaccines, and also a proof that B. bronchiseptica Ag can be used as a vaccine adjuvant as well as vaccine Ag itself.