Activated Vitamin B12, also known as holotranscobalamin (holo-TC), is a significant biomarker for Vitamin B12 status in the body. Unlike total B12, which measures both active and inactive forms, holo-TC specifically indicates the amount of Vitamin B12 that is available for cellular uptake and use. This makes it a more precise marker for assessing B12 deficiency, especially in clinical situations where accurate diagnosis is crucial. Holo-TC is particularly useful because it correlates well with intracellular erythrocyte B12 levels, providing a clearer picture of B12 availability at the cellular level. This biomarker is crucial for diagnosing and monitoring conditions related to Vitamin B12 deficiency, such as neurological disorders and certain types of anemia. The method commonly used for measuring holo-TC is flow cytometry.
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