Fig. 6.

Lysis of E-M-MBL via the lectin pathway and EA via the classical pathway in agammaglobulinemic human serum (AHS), AHS depleted of C4bp (RC4bp), AHS depleted of factor H (RH) and AHS depleted of both C4bp and factor H designated as R(C4bp + H), using otherwise unmodified sera (open bars) and sera which first had been depleted of factor D (RD, solid bars) to exclude alternative pathway amplification. Lysis via the lectin pathway was much greater with an intact alternative pathway, but nonetheless could occur in absence of the alternative pathway in serum depleted of either C4bp or factor H. Standard errors of the mean are indicated by error bars.