CD40LG and vibrio infectious disease: We found that a ≥1.5 fold increase in anti-OSP antibody responses highly correlated with protection against cholera: none of 27 vaccinees who developed ≥1.5 fold increase in any antibody isotype (IgM, IgA, IgG) targeting OSP on day 10 following vaccination compared to baseline developed moderate or severe cholera following experimental challenge, while 5 of 19 (26%) who did not develop any such anti-OSP responses did develop moderate or severe diarrhea (P = 0.01; Table 3 and S1 Table).