The cluster of differentiation (CD) is a nomenclature system that identifies and classifies antigens found on the cell surface of leukocytes. The CD nomenclature is a standardized system developed to classify and name CD molecules based on monoclonal antibody binding, facilitating consistent identification and study of immune cells. Adopted in 1982, the Human Leukocyte Differentiation Antigens organization continues to hold HLDA conferences to maintain and develop the list of known CD markers. CD markers are key cell markers used to identify and classify immune cells, especially white blood cells, in humans.

Explore the complete chart and find your human CD antigen quicker

Under the CD system, antigens that are well characterized are assigned an arbitrary number (eg CD1, CD2, etc.), and these numbers are assigned to specific proteins that are identified on the cell surface. In contrast, molecules recognized by just one monoclonal antibody have the provisional designation ‘CDw’ (eg, CDw50). Lower class letters indicate larger molecules with a chain in common (eg, CD1a or CD1d). Physiologically, CD molecules do not belong to any particular class, with functions ranging from cell surface receptors to adhesion molecules; many CD molecules act as receptor proteins that bind to ligands or other molecules, influencing immune cell activity. The CD molecule naming convention has expanded to cover different species (eg, mice) and other cell types.

The attached poster provides our best products to detect your target of interest, as well as information on the target's expression and functions from relevant scientific literature. The presence or present status of specific CD markers is crucial for identifying cell types and disease states.

CD1a

CD1a is a glycoprotein expressed on dendritic cells and Langerhans cells, playing a role in lipid antigen presentation. It belongs to the CD1 family, which is structurally similar to MHC class I molecules. CD1a is often used in immunophenotyping to identify specific cell populations in dermatological and hematological research. Its expression can help distinguish between different types of skin lesions and leukemias. Researchers continue to explore CD1a’s involvement in immune responses, making it a useful marker in both diagnostic and investigative settings.

Figure 1. Multiplex immunohistochemistry - Anti-CD1a antibody [EPR26526-62] (ab313875).

Recommended products

CD1b

CD1b is a transmembrane glycoprotein that presents lipid and glycolipid antigens to T-cell receptors, particularly on natural killer T (NKT) cells. Unlike classical MHC molecules, CD1b specializes in non-peptide antigen presentation, contributing to immune responses against microbial lipids. It is expressed on dendritic cells and monocytes and is used in studies of tuberculosis, autoimmune diseases, and cancer. CD1b’s unique antigen presentation pathway makes it a valuable marker for investigating host–pathogen interactions and the role of lipid-reactive T cells in immunity.

Figure 2. Immunohistochemistry (Formalin/PFA-fixed paraffin-embedded sections) - Anti-CD1b antibody [EP7251] (ab173576).

Recommended products

CD1c

CD1c is a membrane-bound glycoprotein involved in presenting lipid and glycolipid antigens to T-cell receptors, including those on natural killer T (NKT) cells. It plays a role in non-peptide antigen presentation, contributing to immune responses against bacterial and fungal pathogens. CD1c is expressed on dendritic cells and B cells and is commonly used in immunophenotyping and research on antigen processing. Its unique function in lipid antigen presentation makes CD1c a useful marker in studies of infectious disease, autoimmunity, and cancer immunology.

Figure 3. Western blot - Anti-CD1c antibody [OTI2F4] (ab156708).

Recommended products

CD1d

CD1d is a membrane glycoprotein that presents lipid-based antigens to T-cell receptors, particularly on invariant natural killer T (iNKT) cells. Unlike classical MHC molecules, CD1d specializes in non-peptide antigen presentation, supporting immune responses to self and microbial lipids. It is expressed on dendritic cells, B cells, and some epithelial cells. CD1d is widely studied in immunology for its role in inflammation, infection, and tumor surveillance. Its unique function makes it a useful marker in research exploring lipid-reactive T cells and immune regulation.

Figure 4. Flow Cytometry - Anti-CD1d antibody [EPR22526-9] (ab256344).

Recommended products

CD1e

CD1e is a unique member of the CD1 family involved in processing lipid antigens within endosomal compartments. Unlike other CD1 molecules, CD1e does not present antigens directly to T cells but facilitates the loading of lipid antigens onto CD1b and CD1c. It is expressed in dendritic cells and plays a role in shaping immune responses to microbial lipids. CD1e is studied in the context of antigen presentation, intracellular trafficking, and host–pathogen interactions, making it a useful marker in immunological research.

Figure 5. Immunohistochemistry (Formalin/PFA-fixed paraffin-embedded sections) - Anti-CD1E antibody [EPR15746(B)] - BSA and Azide free (ab250917).

Recommended products