Our Health Library information does not replace the advice of a doctor. Please be advised that this information is made available to assist our patients to learn more about their health. Our providers may not see and/or treat all topics found herein.

Alloimmunization

Alloimmunization is a response by the body's immune system to donated blood or bone marrow or a transplanted organ. In alloimmunization, a person's body develops antibodies—proteins that attack and destroy foreign substances—that target the donated material.

A person receiving repeat blood transfusions may develop antibodies to the donor blood. Alloimmunization makes repeated transfusions more difficult.

Current as of: May 1, 2026

Author: WebMD Ignite Staff

Clinical Review Board
All WebMD Ignite education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

News & Events

View All

Low Iron in Teen Athletes: Signs, Symptoms & What Parents Should Know

Low Iron in Teen Athletes: What Parents Should Know Written in collaboration with Dr. Petra Hackenberg-Bauer, MD School sports are back,

Call

Directions

Facebook

YouTube