Full length article Screening for novel central nervous system biomarkers in veterans with Gulf War Illness Mohamed B. Abou-Donia a, ⁎, Lisa A. Conboy b ,Efi Kokkotou c , Eric Jacobson d,i , Eman M. Elmasry e , Passent Elkafrawy f , Megan Neely g , Cameron R. 'Dale' Bass h , Kimberly Sullivan h a Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, United States b Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States c Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States d Department of Global Health and Social Development, Harvard Medical School, United States e Department of Microbiology, Zagazig University, Zagazig, Egypt f Department of Math and Computer Science, Menoufia University, Shebin ElKom, Egypt g Department of Biostatistics & Bioinformatics, Duke University Medical Center, United States h Biomedical Engineering Department, Duke University, United States i Department of Environmental Health, Boston University School of Public Health, Boston, MA, United States abstract article info Article history: Received 10 May 2016 Received in revised form 2 March 2017 Accepted 3 March 2017 Available online 9 March 2017 Gulf War illness (GWI) is primarily diagnosed by symptom report; objective biomarkers are needed that distin- guish those with GWI. Prior chemical exposures during deployment have been associated in epidemiologic stud- ies with altered central nervous system functioning in veterans with GWI. Previous studies from our group have demonstrated the presence of autoantibodies to essential neuronal and glial proteins in patients with brain injury and autoantibodies have been identified as candidate objective markers that may distinguish GWI. Here, we screened the serum of 20 veterans with GWI and 10 non-veteran symptomatic (low back pain) controls for the presence of such autoantibodies using Western blot analysis against the following proteins: neurofilament triplet proteins (NFP), tubulin, microtubule associated tau proteins (Tau), microtubule associated protein-2 (MAP-2), myelin basic protein (MBP), myelin associated glycoprotein (MAG), glial fibrillary acidic protein (GFAP), calcium-calmodulin kinase II (CaMKII) and glial S-100B protein. Serum reactivity was measured as arbi- trary chemiluminescence units. As a group, veterans with GWI had statistically significantly higher levels of au- toantibody reactivity in all proteins examined except S-100B. Fold increase of the cases relative to controls in descending order were: CaMKII 9.27, GFAP 6.60, Tau 4.83, Tubulin 4.41, MAG 3.60, MBP 2.50, NFP 2.45, MAP-2 2.30, S-100B 1.03. These results confirm the continuing presence of neuronal injury/gliosis in these veterans and are in agreement with the recent reports indicating that 25 years after the war, the health of veterans with GWI is not improving and may be getting worse. Such serum autoantibodies may prove useful as bio- markers of GWI, upon validation of the findings using larger cohorts. © 2017 Elsevier Inc. All rights reserved. Keywords: Gulf War Illness Brain injury Autoantibodies Cytoskeletal proteins Serum biomarkers 1. Introduction Approximately one third of the 697,000 US military personnel who served in the Gulf War (GW) from August 1990 to June 1991, have re- ported persistent symptoms for many years after the war (RAC, 2008; IOM, 2012, RAC, 2016; White et al., 2016). This complex of symptoms, known as Gulf War Illness (GWI), include memory and attention prob- lems, profound fatigue, chronic muscle and joint pain, severe headaches, persistent diarrhea, respiratory difficulties and skin rashes. GWI is primarily diagnosed by symptom report and no validated objective diagnostic biomarkers currently exist that fully segregate cases from controls. This study was designed to identify objective central nervous system (CNS) biomarkers of GWI using clues from prior clinical studies with GW veterans and from animal studies that modeled chemical exposures experienced by GW veterans. Clinical studies have reported impaired cognitive functioning and reduced MRI volume and altered white matter microstructural integrity in organophosphate (OP) pesticide, sarin nerve agent and pyridogstigmine bromide (PB) anti-nerve gas pill-exposed GW veteran cohorts (White et al., 2016; Sullivan et al., 2013; Chao et al., 2010; Neurotoxicology and Teratology 61 (2017) 36–46 ⁎ Corresponding author at: Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, United States. E-mail address: donia@duke.edu (M.B. Abou-Donia). http://dx.doi.org/10.1016/j.ntt.2017.03.002 0892-0362/© 2017 Elsevier Inc. All rights reserved. Contents lists available at ScienceDirect Neurotoxicology and Teratology journal homepage: www.elsevier.com/locate/neutera