Final answer:
a. Rh antibodies may cause delayed HTR, can bind complement on RBC membrane, RBC destruction is usually extravascular, Rh Ab may cause secondary immune response.
Step-by-step explanation:
a. Rh Ab's may cause delayed HTR:
Although Rh antibodies can cause a delayed hemolytic transfusion reaction (HTR), this is not true for all Rh individuals. Only individuals who have been sensitized to Rh antigens through exposure to Rh-positive red blood cells (RBCs) can develop Rh antibodies and experience a delayed HTR.
Rh Ab's can bind complement on the RBC membrane:
Rh antibodies have the ability to bind complement proteins on the surface of Rh-positive RBCs, leading to complement-mediated lysis of the RBCs. This process is an important mechanism in the destruction of RBCs in Rh incompatibility reactions.
RBC destruction is usually extravascular:
In most cases of Rh incompatibility, RBC destruction occurs extravascularly, meaning it takes place outside of the bloodstream. The RBCs are usually sequestered and destroyed in the spleen or liver.
An individual with a low titer Rh Ab may experience a secondary immune response on antigen exposure:
This statement is true. Individuals with a low titer (low concentration) of Rh antibodies may still experience a secondary immune response upon exposure to Rh antigens. The secondary immune response is faster and stronger compared to the primary response, resulting in a more rapid hemolytic transfusion reaction (HTR) upon subsequent exposure to Rh-positive RBCs.