CD56 (NCAM) Antibodies

Function and NK Cell Identification

What Is CD56 (NCAM)?

CD56, also referred to as neural cell adhesion molecule (NCAM), is a surface glycoprotein involved in cell adhesion, migration, and signaling. In immunology, it is commonly used as a marker for natural killer (NK) cells and certain T-cell subsets to support identification and characterization of immune populations.

Which Cells Express CD56?

CD56 expression is typically observed on:

  • Natural killer (NK) cells
  • CD56+ T-cell subsets—also known as NK-like T cells
  • Neuroendocrine and neural-derived cells

Because it is expressed across both immune and non-immune cell types, CD56 is often used alongside other markers to provide additional context.

CD56 in Flow Cytometry and Immunophenotyping

CD56 antibodies are frequently used in flow cytometry to identify and assess NK cells in peripheral blood, bone marrow, and tissue samples. When combined with markers such as CD3 or CD16, CD56 can support more detailed analysis of immune cell subsets.

Common CD56 Panel Combinations

  • CD56 + CD3 — distinguishes NK cells (CD56+CD3−) from T cells (CD3+)
  • CD56 + CD16 — helps differentiate NK cell functional subsets 
  • CD56 + CD45 — used within broader leukocyte gating strategies

CD56 Bright and CD56 Dim NK Cells

Differences in CD56 expression levels define two main NK cell subsets with distinct roles:

Subset CD56 Expression Function Location
CD56bright High Cytokine production and immune regulation Lymphoid tissues
CD56dim Low Cytotoxic activity (target cell killing) Peripheral blood

These subsets contribute differently to immune responses, including roles in infection, inflammation, and tumor surveillance.

Applications of CD56 Antibodies

  • Identification and quantification of NK cells in flow cytometry
  • Immunophenotyping of lymphocyte populations
  • Characterization of T-cell subsets
  • Detection of neuroendocrine and neural-derived tumors
  • Research into immune responses and disease biology

CD56 in Research and Disease

CD56 is used as a marker in a range of research and clinical contexts. In immunology studies, it is associated with NK-cell activity, while in oncology it is expressed in neuroendocrine tumors and some hematological malignancies, including NK/T-cell lymphomas.

Selecting a CD56 Antibody

  • Application — consider compatibility with your chosen application, such as flow cytometry, IHC, or western blotting
  • Fluorophore — align with instrument configuration and consider panel design for multicolor assays
  • Clone — use validated clones suitable for the species and assay
  • Panel design — minimize spectral overlap in multicolor experiments

Appropriate selection can help support clear separation of CD56+ and CD56− populations and improve reproducibility.

Our range of CD56 antibodies (also known as NCAM, Leu-19, or NKH1) are available in a range of formats suitable for applications including flow cytometry, western blotting, immunohistochemistry, immunoprecipitation, and ELISA.

Please use the filters in the table below to refine results based on your experimental requirements. For further guidance, you can contact technical support.

Our CD56 Antibody Range

    DescriptionSpecificityTargetFormatHostIsotypeClone Applications Citations Product Type Code Validation Types

    Frequently Asked Questions

    What is CD56 used for?

    CD56 is used to help identify natural killer (NK) cells and certain T-cell subsets in immunophenotyping workflows.

    Is CD56 a marker for NK cells?

    Yes, CD56 is widely used as a marker for NK cells, typically in combination with CD3 to distinguish them from T cells.

    What does CD56 positive mean?

    CD56 positivity indicates that a cell expresses the NCAM protein on its surface. Interpretation depends on the broader panel and sample context.

    What is the difference between CD56 bright and dim?

    CD56bright NK cells are mainly involved in cytokine production and immune regulation, while CD56dim NK cells are more cytotoxic.

    Related NK Cell Resources

    CD56 is commonly included in NK cell immunophenotyping panels. For additional markers associated with NK cell receptors and function, see:

    NK cell receptor antibodies