Your Friend Ellie Is Pregnant

Your friend Ellie is pregnant. She tells you that her mother, a microbiologist, has warned her not to clean out the cat's litter box while she is pregnant in case she contracts a disease called toxoplasmosis, which can affect her fetus. She says her mom told her toxoplasmosis is caused by a parasite called Toxoplasma gondii, that may be found in the feces of infected cats and also in raw meat. Your friend's mom tells her that when a person has not had a particular disease, they are not immune to the pathogen that causes the disease, and lack antibodies against that microbe. Your friend has never had toxoplasmosis but she doesn't quite understand why this, and the fact that she doesn't have antibodies to T. gondii, is important. You help her understand some facts about her adaptive immune system.
-Ellie doesn't understand why it is important as to whether a woman has a first or subsequent exposure to a pathogen such as T. gondii when she is pregnant. You explain to her the difference between a primary and a secondary immune response. Which of the following would you NOT say to her?

A) When memory B cells become activated, some quickly differentiate to form plasma cells, resulting in the rapid production of antibodies. IgG crosses the placenta and protects the fetus.
B) In the first (primary) exposure to an antigen, it takes about 10 to 14 days for a significant concentration of antibodies to accumulate. IgM is made, followed by IgG.
C) The second exposure to an antigen, which characterizes the memory of adaptive immunity, causes rapid production of relatively large quantities of IgM but no IgG.
D) If the same antigen is encountered later in life, a stronger antigen-specific adaptive immune response occurs, called the secondary response. Large amounts of IgG are made.
E) The first adaptive immune response to an antigen is the primary response; effector cells and memory cells are formed as a result of this initial encounter.