TNFSF13B and serum lipopolysaccharide activity: We reached the following conclusions: (1) BAFF is overexpressed in the serum and in multiple organ tissues of mice with endotoxemia; (2) BAFF blockade improves survival rate and multi-organ dysfunction, and alleviates systemic and intestinal inflammatory response; and (3) BAFF blockade improves intestinal barrier function via upregulating the expression of ZO-1 and occludin TJ proteins.