Lifting the Veil: Characteristics, Clinical Significance, and Application of β-2-Microglobulin as Biomarkers and Its Detection with Biosensors

Because β-2-microglobulin (β2M) is a surface protein that is present on most nucleated cells, it plays a key role in the human immune system and the kidney glomeruli to regulate homeostasis. The primary clinical significance of β2M is in dialysis-related amyloidosis, a complication of end-stage renal disease caused by a gradual accumulation of β2M in the blood. Therefore, the function of β2M in kidney-related diseases has been extensively studied to evaluate its glomerular and tubular functions. Because increased β2M shedding due to rapid cell turnover may indicate other underlying medical conditions, the possibility to use β2M as a versatile biomarker rose in prominence across multiple disciplines for various applications. Therefore, this work has reviewed the recent use of β2M to detect various diseases and its progress as a biomarker. While the use of state-of-the-art β2M detection requires sophisticated tools, high maintenance, and labor cost, this work also has reported the use of biosensor to quantify β2M over the past decade. It is hoped that a portable and highly efficient β2M biosensor device will soon be incorporated in point-of-care testing to provide safe, rapid, and reliable test results.