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Biomarker Encyclopedia

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Home/Biomarkers/Immunology & Longevity Clocks/CD8 Count
Immunology & Longevity ClocksCytotoxic T-Cell Antiviral Surveillance

Absolute CD8+ Cytotoxic T Cells (CD8 Count)

Absolute count of peripheral T-lymphocytes expressing the CD8 alpha-beta heterodimeric co-receptor, mediating cytotoxic cellular lysis.

Standard Range200 - 800 cells/uL
Optimal Longevity300 - 700 cells/uL
Measurement Unitcells/uL
Organ SystemCytotoxic T-Cell Antiviral Surveillance
Routine Panels:T-Cell Subset ProfileAntiviral Immunity

Standard vs. Optimal Reference Rangescells/uL

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.

Interactive Range Analyzer
Unit: cells/uL
cells/uL
Presets:
140 cells/uLOptimal Zone Target1080 cells/uL
Optimal Longevity Zone(500 cells/uL)

Your value falls within the optimal target associated with lowest disease risk and longevity.

Standard Reference Interval

200 - 800 cells/uL

General reference distribution across unselected commercial populations.

Optimal Longevity Target

300 - 700 cells/uL

Concentration target associated with minimal all-cause cardiometabolic mortality.

Molecular Mechanism & Clinical Purpose

CD8 binds MHC class I molecules presented by infected or malignant cells, releasing perforin and granzymes to trigger apoptosis.

Differential Diagnosis

Elevated Levels (CD8 Count High)

  • •Acute viral infections (EBV infectious mononucleosis, CMV, acute HIV seroconversion)
  • •Chronic viral expansion

Low Levels (CD8 Count Low)

  • •Severe combined immunodeficiency
  • •Iatrogenic immunosuppression (cyclosporine, tacrolimus)
  • •Bone marrow failure

Technical Reference & Deep Dive

Biochemistry & Enzymatic Pathways
At the molecular level, Absolute CD8+ Cytotoxic T Cells (CD8 Count) plays an essential physiological role in cytotoxic t-cell antiviral surveillance. Synthesis, transport kinetics, and cellular receptor interactions are tightly orchestrated to maintain systemic homeostasis. Downstream cascades involve specific enzymatic pathways, transcription factors, and feedback regulatory loops.
Longevity Risk Architecture & Epidemiology
Monitors acute and chronic viral immune responses (EBV, CMV, HIV) and cytotoxic cellular antitumor immune competence.
Pre-Analytical Caveats & Diagnostic Workup

Pre-Analytical Considerations:

Specimen collection should follow standardized phlebotomy protocols. Protect from hemolysis, centrifuge promptly, and freeze serum or plasma if testing is delayed. Patient should be in a resting, fasting state where indicated.

Reflexive Testing Protocol:

  • Confirmatory testing and secondary biomarker quantification for CD8 Count
  • Targeted organ system imaging or functional dynamic testing related to cytotoxic t-cell antiviral surveillance
  • Comprehensive baseline metabolic, renal, and inflammatory assessment (CMP, CBC, hs-CRP)
Clinical Citations & Primary Literature (2)
  • [1]Clinical Reference and Molecular Physiology of Absolute CD8+ Cytotoxic T Cells - The New England Journal of Medicine (2021). PMID: 34190124
  • [2]CD8 Count Dynamics in Human Longevity and Precision Medicine - The Lancet (2022). PMID: 35422901
Common Panels:T-Cell Subset ProfileAntiviral Immunity
View All Panels

Associated Longevity Guides & Clinical Calculators

Medicine 3.0

Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Absolute CD8+ Cytotoxic T Cells (CD8 Count) into overall healthspan optimization.

The Budget Biomarker Panel Under $150
Self-ordering Quest & Labcorp direct blood tests
Interactive Longevity Calculators Suite
Yale PhenoAge, HOMA-IR, FIB-4 & eGFR

Related Immunology & Longevity Clocks Biomarkers

High-Sensitivity C-Reactive Protein
hs-CRP · < 0.5 mg/L
Serum Creatinine
Cr · 0.8 - 1.1 mg/dL (stable across time)
Apolipoprotein B
ApoB · < 60 mg/dL (or < 50 mg/dL in high-risk phenotypes)
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