Sex-based differences in plasma autoantibodies to Central Nervous System proteins in Gulf War veterans versus healthy and symptomatic controls, by Mohamed B Abou-Donia, Maxine H Krengel, Elizabeth S Lapadula, Clara G Zundel, Jessica LeClair, Joseph Massaro, Emily Quinn, Lisa A Conboy, Efi Kokkotou, Daniel D Nguyen, Maria Abreu, Nancy G Klimas, Kimberly Sullivan in Brain Sci. 2021 Jan 23;11(2):148 [doi: 10.3390/brainsci11020148] (This article belongs to the Special Issue Advancing the Role of Neuroimmunity and Genetic Susceptibility in Gulf War Illness)
Veterans from the 1991 Gulf War (GW) have suffered from Gulf War illness (GWI) for nearly 30 years. This illness encompasses multiple body systems, including the central nervous system (CNS). Diagnosis and treatment of GWI is difficult because there has not been an objective diagnostic biomarker. Recently, we reported on a newly developed blood biomarker that discriminates GWI from GW healthy controls, and symptomatic controls with irritable bowel syndrome (IBS) and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).
The present study was designed to compare levels of these biomarkers between men and women with GWI, as well as sex-specific effects in comparison to healthy GW veterans and symptomatic controls (IBS, ME/CFS). The results showed that men and women with GWI differ in 2 of 10 plasma autoantibodies, with men showing significantly elevated levels. Men and women with GWI showed significantly different levels of autoantibodies in 8 of 10 biomarkers to neuronal and glial proteins in plasma relative to controls.
In summary, the present study addressed the utility of the use of plasma autoantibodies for CNS proteins to distinguish among both men and women veterans with GWI and other healthy and symptomatic control groups.
Our next analyses compared male veterans with GWI to all male controls from our prior study (healthy GW veterans, non-veterans with IBS or ME/CFS) . We then performed the same analyses comparing women veterans with GWI to the combined all women control group (non-veterans with IBS and ME/CFS). The results showed that men with GWI had significantly higher levels of autoantibodies for 9 out of the 10 autoantibodies when compared with male healthy GW veterans or with the combined male control group. Women with GWI showed significantly higher values for 2 out of the 10 autoantibodies when compared with women healthy GW veterans and with 8 out of 10 autoantibodies when compared with their respective combined women control group (nonveterans with IBS and ME/CFS).
These results suggest that women with GWI appear to be showing more neuronal cytoskeletal and neuroinflammatory changes when compared to healthy GW controls or women with IBS or ME/CFS
This suggests that male GWI veterans may be showing more chronic glial activation, neuronal damage, and neuroinflammation than their male control healthy and symptomatic counterparts with IBS and ME/CFS because S100B is a marker of current BBB disruption and GFAP is a marker of current neuroinflammation [39,40]. This is because GFAP is secreted by activated astrocytes, which leads to neuroinflammation [41,42,43].
A major strength of our study is that it represents both healthy and symptomatic GW veteran groups as well as symptomatic non-veteran controls with ME/CFS or IBS. This suggests that both men and women veterans with GWI differ not only from their healthy GW veteran controls but also have more CNS differences than other groups of men and women with chronic multi-symptom illnesses. In addition, the CNS autoantibody analyses were performed with the laboratory staff blinded to the case status of all participants.