CD40LG and infection: As would have been anticipated, IgG half-maximal binding dilution (ED50) values correlated best with the serum dilution that inhibits 50% infection (ID50) values for the BTI group, whereas IgM ED50 values correlated best with ID50 values for the vaccine-naive group (Fig. 2E and F), further highlighting the priming capacity of both the AZ1222 and BNT162b2 vaccines.