Spleen ?????

Hi
I have not had a spleen all my life! Mine ruptured at birth, What would taking a spleen glandular do as I do not have one to strengthen. My ND said it will help my immune system, and wants me to take it. Not having something for so long and then bam, I don't want to be more sick, I am just starting to feel better. I am a little leery(sp?)Although the Adrenal glandular has helped me quite abit.

Thanks