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Antibody titer

Antibody titer

Overview

The antibody level in the blood is a reflection of the body's past experience or exposure to an antigen, or something that the body does not recognize as self. Every living cell has different protein markers on its surface called antigens, and the body's immune system identifies those cells that are not part of its structure by those surface proteins.

Review Date 3/31/2024

Updated by: Deborah Pedersen, MD, MS, Allergy & Asthma Care, PC, Taunton, MA. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.