The functional capacity of Complement was compared in the serum samples obtained from two different individuals. The test was run by incubatng RBCâs, coated with anti-RBC antibodies, with each of the serum samples. Incubation with serum from donor A for an appropriate period of )me resulted in the lysis of the RBCâs. However, the same test run with serum from donor B failed to show lysis of the RBCâs. Interestingly, when bacteria were incubated with either of the serum samples, the bacteria were opsonized with C3b. The bacteria used to perform the opsonization test had been engineered so that they could not ac)vate the alternative or MBL pathways of complement.
Based on your knowledge of Complement activation, defect in which of the following complement components in donor B would explain the above findings?
A. C1q
B. C4
C. C2
D. C3
E. C5
The functional capacity of Complement was compared in the serum samples obtained from two different individuals. The test was run by incubatng RBCâs, coated with anti-RBC antibodies, with each of the serum samples. Incubation with serum from donor A for an appropriate period of )me resulted in the lysis of the RBCâs. However, the same test run with serum from donor B failed to show lysis of the RBCâs. Interestingly, when bacteria were incubated with either of the serum samples, the bacteria were opsonized with C3b. The bacteria used to perform the opsonization test had been engineered so that they could not ac)vate the alternative or MBL pathways of complement.
Based on your knowledge of Complement activation, defect in which of the following complement components in donor B would explain the above findings?
A. C1q
B. C4
C. C2
D. C3
E. C5
