Answer :
antigen is any substance capable of inducing a specific immune response and of reacting with the products of that response, i.e., with specific antibody or specifically sensitized T lymphocytes, or both.
autologous means obtained from the same individual.
autologous means obtained from the same individual.
Antigens are agents that are capable of eliciting an immune response in our body. Mostly they are foreign agents.The antigen may originate from within the body ("self") or from the external environment ("non-self"). The antigens that are produced by our body itself are called autologous antigens.