Question

1) Phage therapy is challenging to develop because

a) phages can readily infect human cells

b) patients refuse to be injected with virions

c) target bacteria evolve rapidly to escape infection

d) all answers are wrong

2) what will happen if there is no negative selection of T-cell receptors?

a) T cell receptors could not bind to CD4 or CD8 proteins

b) T cell receptors could not bind to MHC proteins

c) the immune system could not recognize pathogen antigens.

d) the immune system could not distinguish self-antigens

Answer 1

1- (d) All answers are worng.

Because bacteriophage cannot infect and replicted inside the human cell. The injection is a big issue. But here the problems is the safety and reliability of the trial of phase therapy on animals or human bodies.

2- (b) T cell receptors could not bind to MHC protein.

Because T cell receptors must be negatively selected to bind with the MHC protein. If there is no negatively selected T cell that means the receptors never bind with the MHC protein.