Circulating IgA antibodies against Fusobacterium nucleatum amyloid adhesin FadA are a potential biomarker for colorectal neoplasia

摘要: Fusobacterium nucleatum (Fn) is a gram-negative oral anaerobe and prevalent in colorectal cancer. Fn encodes a unique amyloid-like adhesin, FadA complex (FadAc), consisting of intact pre-FadA and cleaved mature FadA, to promote colorectal cancer tumorigenesis. We aimed to evaluate circulating anti-FadAc antibody levels as a biomarker for colorectal cancer. Circulating anti-FadAc IgA and IgG levels were measured by ELISA in two study populations. In study 1, plasma samples from patients with colorectal cancer (n = 25) and matched healthy controls (n = 25) were obtained from University Hospitals Cleveland Medical Center. Plasma levels of anti-FadAc IgA were significantly increased in patients with colorectal cancer (mean ± SD: 1.48 ± 1.07 μg/mL) compared with matched healthy controls (0.71 ± 0.36 μg/mL; P = 0.001). The increase was significant in both early (stages I and II) and advanced …