Question

Why is a 500-Da plasma protein from a chimpanzee likely to "fall under the radar" of the adaptive immune system?

a) Because it is a bacterial toxin.
b) Because it lacks sufficient numbers of epitopes.
c) Because it's an immunogenic molecule.
d) Because it's a cholesterol molecule.
e) Because it's a carbohydrate molecule expressed by host tissues.

Answer 1

A 500-Da chimpanzee plasma protein is likely ignored by the adaptive immune system due to insufficient epitopes. The immune system, while effective and diverse in antibody production, can still be evaded by pathogens that develop escape mechanisms.

Step-by-step explanation:

A 500-Da plasma protein from a chimpanzee is likely to "fall under the radar" of the adaptive immune system because it lacks sufficient numbers of epitopes. Proteins need to be of a certain size and complexity to present multiple epitopes, which are parts of antigens that immune cells recognize and to which antibodies can bind. A small protein like one that is only 500-Da may not have enough epitopes to be effectively recognized by the immune system, especially if it is similar to the host's own proteins, causing the immune system to overlook it as a potential threat.

The adaptive immune system is highly efficient and effective, capable of producing a vast diversity of antibodies due to mechanisms such as V(D)J recombination, somatic hypermutation, and class switching. These allow the immune system to respond to a wide variety of antigens with a limited number of genes. Despite its sophistication, pathogens can evolve mechanisms to avoid immune detection, emphasizing the importance of both innate and adaptive immunity in defending against disease.