Protective Effect of Stem Cells from Toxicity Induced by Gulf War Illness (GWI) Serum in N2A Neuroblastoma Cells.

Gulf War Illness (GWI) afflicted many veterans of the 1990-91 Gulf War with multiple symptoms worsening with time. The reasons for GWI have not been elucidated but may include toxicity due to inflammatory factors induced by vaccines administered to deployed and nondeployed veterans. In particular, the anthrax vaccine may have harmful effects in veterans lacking specific protective HLA alleles, as we reported previously, using a murine neuroblastoma N2A cell culture system. Lack of these protective alleles could allow several vaccine antigens to circulate chronically, resulting in protracted low-grade inflammation accompanying the disease. When N2A cells were exposed to GWI serum or the antigen of the anthrax vaccine, the cells underwent apoptosis due to compromised cell membrane, mitochondrial and cytoskeletal function. Elucidation of mechanisms of GWI should provide clues for therapy. Since antigen-induced inflammation accompanies GWI and stem cells were reported to have antimicrobial activity, we examined the effect of murine stem cells co-cultured with N2A cells before exposure to GWI serum and also Protective Antigen PA63, the main component of the anthrax vaccine. The presence of stem cells completely prevented GWI serum toxicity, since it resulted in inhibition of apoptosis. Moreover, cultures of stem cells exposed to PA63 resulted in the degradation of this antigen. We conclude that stem cells can protect against vaccine-induced toxic components of the GWI serum in N2A cells, prompting further studies on the possible beneficial effects of these cells in GWI.