CD40LG and Epstein-Barr virus infection: As defined in Table 1, criteria to determine a recent or reactivated EBV infection can be determined by using four different antibody titer assays, including IgM and IgG antibodies against the viral capsid antigen (VCA), IgG against the nuclear antigen 1 (EBNA1), and IgG against a complex of early antigens (EA).