CD40LG and infection: Reactivity to all three carbohydrates was higher for the IgM response in the first week post infection (IgM fold changes from pre-challenge samples: LPSA 6.0, LPSB 2.1, CPS 13.1; IgG fold changes from pre-challenge samples: LPSA 5.2, LPSB 1.8, CPS 9.2).