Immunoaffinity Purification of Acinetobacter baumannii Antigen(s) That Potentially Induce Multiple Sclerosis — 27p — Kelsey Morrison, Cane Schmitt, Dr. Chun Wu

Multiple sclerosis (MS) is an autoimmune disease disorder in which the body’s immune system attacks the protective covering of the nerve cells, specifically the myelin sheath. Patients with MS were observed and found to have abnormally elevated levels of a certain Gram-negative bacteria called Acinetobacter baumannii. Our previous “in silico” study identified sequence homologies between the protein sequence of Acinetobacter baumannii and the peptide sequences present in human Myelin Oligodendrocyte Glycoprotein (MOG). Western blot analysis indicated that human polyclonal anti-MOG IgG antibodies demonstrated recognition of the same protein(s) in Acinetobacter baumannii around 25 kilodalton. In this study, we employed immunoaffinity chromatography and immunoprecipitation to isolate the antigen-antibody complex. We have used non-reducing SDS-PAGE and Western Blot analysis and were shown 2 bands located at 175 and 25 kilodalton. Proteomic analysis demonstrated that the 25 kilodalton band is a member of CoA transferase, which was not previously identified. In addition, the 175 kilodalton band is confirmed to be the conjugate of this same member of CoA transferase and anti-MOG IgG. Recently, we purchased our second human protein complex, Proteolipid Protein (PLP) and initiated the identification of AB protein which recognizes Anti-PLP IgG. These results imply an antigen-antibody complex, and are under further analysis at the USD Proteomics lab. These approaches have helped enable us to gain a better understanding of the specific molecular interactions between the Acinetobacter baumannii antigens and the anti-MOG, anti-PLP antibodies, all shedding light on the potential mechanisms underlying the pathogenesis of MS. The identification of Acinetobacter baumannii antigen(s) which recognize human myelin peptide antibodies holds significant promise in advancing our understanding of MS etiology.

Mount Marty University
Dr. Chun Wu