Activated T-Cell Marker Test: HLA-DR, CD38, Immune Activation, and Inflammation
An activated T-cell marker test uses flow cytometry to estimate how many T lymphocytes are showing signs of recent or ongoing stimulation. Laboratories may...
B-Cell Count Test: CD19, CD20, Immune Function, and Antibody Production
A B-cell count test measures the number and percentage of B lymphocytes in blood, usually by flow cytometry. Laboratories most often identify B cells...
CD4 Count Test: Helper T Cells, Immune Function, HIV Monitoring, and Meaning
A CD4 count measures helper T cells, a group of lymphocytes that coordinate immune responses against infections and support B cells, macrophages, and cytotoxic...
CD4/CD8 Ratio Test: Immune Balance, High and Low Ratio, and Meaning
The CD4/CD8 ratio compares helper T cells with cytotoxic T cells in a blood sample. It is calculated by dividing the absolute CD4 count...
CD8 Count Test: Cytotoxic T Cells, Immune Function, and Viral Response
A CD8 count measures a major group of T lymphocytes involved in recognizing and removing virus-infected, damaged, or abnormal cells. The cells are often...
Chemokine Panel Test: Immune Signaling, Inflammation, and Cell Migration Markers
A chemokine panel measures several small immune-signaling proteins that help direct white blood cells toward infection, injury, tumors, or inflamed tissue. Unlike a routine...
Cytokine Panel Test: IL-1, IL-6, IL-8, TNF-Alpha, Interferon-Gamma, and Immune Activation
A cytokine panel measures a group of proteins that immune and tissue cells use to communicate. Common targets include interleukin-1 beta, interleukin-6, interleukin-8, tumor...
Cytokine Storm Blood Test Panel: IL-6, Ferritin, CRP, D-Dimer, and Severe Inflammation
A “cytokine storm blood test panel” is not one standardized laboratory test. It is a group of tests used to look for severe, dysregulated...
Flow Cytometry Immune Panel: Lymphocyte Markers, Immune Cells, and Immune Deficiency
A flow cytometry immune panel identifies and counts immune-cell populations by detecting markers on or inside individual cells. A basic lymphocyte panel usually reports...
Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) Test: Immune Activation and Inflammation
A granulocyte-macrophage colony-stimulating factor test measures GM-CSF, also called CSF2, in blood or another specimen. GM-CSF is a cytokine that helps myeloid cells—including monocytes,...
Interferon-Alpha Test: Antiviral Immune Activity and Inflammation Meaning
An interferon-alpha test looks at one part of the body’s early antiviral defense system. Interferon-alpha, usually written IFN-α, is a family of type I...
Interferon-Gamma Test: Immune Activation, Infection Response, and T-Cell Activity
An interferon-gamma test can mean several different laboratory procedures, and the distinction changes the interpretation. Interferon-gamma, or IFN-γ, is a cytokine made mainly by...
Interleukin-1 Beta (IL-1β) Test: Inflammation, Immune Activation, and Autoinflammatory Disease
An interleukin-1 beta test measures a powerful inflammatory cytokine, but it is not a general-purpose test that can diagnose inflammation by itself. Interleukin-1 beta,...
Interleukin-2 (IL-2) Test: T-Cell Activation, Immune Response, and Meaning
An interleukin-2 (IL-2) test measures a cytokine that activated T cells release to coordinate immune-cell growth, survival, and regulation. Although IL-2 is often described...
Interleukin-4 (IL-4) Test: Allergy, Th2 Immune Response, and Immune Signaling
An interleukin-4 (IL-4) test measures a cytokine central to type 2 immunity, the immune program involved in defense against parasites, tissue repair, antibody class...
Interleukin-5 (IL-5) Test: Eosinophilic Inflammation, Allergy, Asthma, and Meaning
An interleukin-5 (IL-5) test measures a cytokine that promotes eosinophil development, survival, activation, and movement from bone marrow into blood and tissues. IL-5 is...
Interleukin-6 (IL-6) Test: High Levels, Inflammation, Cytokine Activity, and Immune Response
An interleukin-6 (IL-6) test measures a rapidly changing cytokine involved in infection defense, inflammation, antibody responses, blood-cell production, metabolism, and tissue repair. IL-6 can...
Interleukin-8 (IL-8) Test: Neutrophil Inflammation, Infection Response, and Meaning
An interleukin-8 (IL-8) test measures a chemokine—also named CXCL8—that directs neutrophils toward infection, tissue injury, and other inflammatory signals. IL-8 can rise quickly when...
Interleukin-10 (IL-10) Test: Immune Regulation, Inflammation Control, and Meaning
An interleukin-10 test measures a cytokine that helps prevent an immune response from causing unnecessary damage. Interleukin-10, abbreviated IL-10, is often described as anti-inflammatory,...
Interleukin-12 (IL-12) Test: Immune Activation, T-Cell Response, and Meaning
An interleukin-12 test measures a cytokine that connects early innate immune sensing with a strong cellular immune response. Interleukin-12, or IL-12, is produced mainly...



















