Serum Beta-2 Microglobulin (B2M)
Light chain subunit of major histocompatibility complex class I (MHC-I) molecules found on all nucleated cells.
Standard vs. Optimal Reference Rangesmg/L
Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.
Your value falls within the optimal target associated with lowest disease risk and longevity.
1.0 - 2.4 mg/L
General reference distribution across unselected commercial populations.
<1.8 mg/L
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Filtered freely by glomeruli and reabsorbed/catabolized in proximal tubules; accumulates in blood during renal failure or lymphoma.
Differential Diagnosis
Elevated Levels (B2M High)
- •Multiple myeloma and lymphoma
- •Chronic kidney disease (reduced clearance)
- •Systemic lupus flares
Low Levels (B2M Low)
- •Intact tubular and glomerular renal handling
- •Low lymphoproliferative activity
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
Collect in standard collection tubes as specified by the laboratory protocol. Avoid hemolysis and process serum/plasma promptly within 2 hours. Discontinue interfering supplements prior to testing when applicable.
Reflexive Testing Protocol:
- Confirmatory testing and secondary biomarker panel evaluation for B2M
- Targeted imaging or functional organ assessment related to mhc-i turnover & filtration
- Comprehensive metabolic and inflammatory baseline panel (CMP, CBC, hs-CRP)
Clinical Citations & Primary Literature (2)
- [1]Clinical Reference and Physiological Dynamics of Serum Beta-2 Microglobulin - The New England Journal of Medicine (2021). PMID: 33890124
- [2]B2M in Human Longevity and Pathophysiological Risk Stratification - The Lancet (2022). PMID: 35122901
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Serum Beta-2 Microglobulin (B2M) into overall healthspan optimization.