Anti-Mouse Dendritic Cells – Purified in vivo GOLD™ Functional Grade

Clone 33D1 is extensively used in in vivo mouse studies as a tool for dendritic cell depletion to investigate the functional roles of dendritic cells in various biological processes and disease models.

Primary Application: Dendritic Cell Depletion

The 33D1 monoclonal antibody serves as a powerful research tool for selectively removing dendritic cells from living mice to study their functional importance. The antibody works through complement-mediated cytotoxicity, where it binds specifically to the DCIR2 (Dendritic cell inhibitory receptor 2) antigen expressed on dendritic cells and kills them in the presence of complement.

Mechanism of Action

The 33D1 antibody demonstrates remarkable specificity for dendritic cells, with quantitative binding studies showing that dendritic cells have an average of 14,000 binding sites per cell. This specificity is crucial for in vivo studies because the antibody kills 80-90% of dendritic cells from spleen and lymph nodes while leaving other immune cell populations, including macrophages, lymphocytes, and granulocytes, completely unaffected.

Research Applications

Disease Model Studies: The 33D1 antibody has been particularly valuable in studying autoimmune and inflammatory conditions. Research has demonstrated that DCIR2-expressing dendritic cells can ameliorate diseases with strong immune inflammatory components, including experimental autoimmune encephalomyelitis (EAE), experimental melanoma, and diabetes.

Metabolic Research: Recent studies have utilized 33D1 for investigating the role of conventional type 2 dendritic cells (cDC2) in diet-induced obesity and inflammation, revealing how specific dendritic cell subsets contribute to metabolic disorders.

Immune Function Studies: In vivo depletion studies using 33D1 have shown that removing dendritic cells from unfractionated spleen suspensions reduces stimulatory capacity by 75-90 percent in mixed leukocyte reactions, demonstrating their critical role as the principal stimulators of primary immune responses.

Methodological Advantages

The 33D1 system offers several key advantages for in vivo research. The antibody recognizes a stable antigen that dendritic cells continue to express even after 4 days in culture, while other cell types do not acquire this marker. This stability makes it reliable for longitudinal studies. Additionally, the high specificity ensures that observed effects can be attributed specifically to dendritic cell depletion rather than off-target effects on other immune cell populations.

The correct storage temperature for sterile packaged clone 33D1 (a monoclonal antibody) is 2°C to 8°C (refrigerated), protected from light, and do not freeze.

• According to multiple antibody suppliers and manufacturers, clone 33D1 should be stored in the refrigerator, undiluted.
• Freezing is not recommended as it can compromise antibody integrity.
• For most formats, store in the dark to prevent photodegradation.
• These recommendations are specific to antibody reagents. If you are referring to a different context (such as live cloned cells or a different clone 33D1 product), please clarify, as storage requirements may differ.

Always follow the manufacturer's instructions provided with the product for the most reliable results.

Other commonly used antibodies or proteins in the literature alongside 33D1 (which recognizes mouse DCIR2, marking conventional type 2 dendritic cells, or cDC2) include markers that distinguish dendritic cell subsets, as well as markers for T cells, B cells, and macrophages for immune cell characterization.

Key antibodies and proteins used with 33D1:

• CD11c: A standard marker for all dendritic cells (DCs), often used for gating DC populations in flow cytometry and distinguishing dendritic cell subsets from other immune cells.
• F4/80: Recognizes macrophages; often used in combination to discriminate DCs (33D1+ and CD11c+) from macrophages (F4/80+).
• CD8?: Used to distinguish cDC1 (CD8?+ dendritic cells) from cDC2 (DCIR2/33D1+ dendritic cells). Researchers often compare responses or deplete specific DC subsets using anti-CD8? and anti-33D1 antibodies.
• CD4 and CD3: Frequently used in studies involving T cell priming to monitor interaction with 33D1+ DCs.
• MHC-II (I-A/I-E): Used for identifying antigen-presenting cells and assessing their maturation status alongside dendritic and T cell markers.
• B220 (CD45R): Used to distinguish plasmacytoid dendritic cells (B220+) from conventional dendritic cells (CD11c+ DCIR2/33D1+).
• DEC-205 (CD205): Another dendritic cell surface marker; anti-DEC205 antibody often paired with 33D1 to differentiate cDC2 (33D1+) from cDC1 (DEC205+).

These markers are widely used in applications such as flow cytometry, immunofluorescence, and cell sorting to define DC subset composition, study immune responses, or selectively deplete or target dendritic cell populations in experimental mouse models.

Summary Table: Common Markers Used with 33D1

For subset gating and functional studies, combinations like 33D1/CD11c, 33D1/DEC205, and 33D1/F4/80 are very common in mouse immunology research.

Clone 33D1 is a well-characterized monoclonal antibody widely used for identifying and functionally depleting specific subpopulations of mouse dendritic cells (DCs), particularly those expressing the DCIR2 (Clec4a4) antigen. Key scientific findings from its extensive citations are summarized below:

• Specificity for Mouse Dendritic Cells:
  33D1 binds specifically to dendritic cells, and not to macrophages or other splenocytes, as demonstrated by both immunofluorescence and cytotoxicity assays. This makes it a precise tool for targeting DCs in both in vitro and in vivo experiments.

• Functional Depletion of DCs:
  In the presence of rabbit complement, 33D1 can selectively kill dendritic cells, allowing researchers to study the consequences of DC depletion on immune responses. Removing DCs using 33D1 and complement severely reduces the immune system’s capacity to stimulate mixed leukocyte reactions (MLR)—by about 75-90%—showing that DCs are principal stimulators of primary immune responses.

• Comparison with Other Antibodies:
  While F4/80 is a marker for macrophages, 33D1 exclusively binds DCs, confirming its unique specificity for the dendritic cell lineage in mouse models.

• Antigen Identity and Expression:
  The antigen recognized by 33D1 is known as DCIR2 (Dendritic cell inhibitory receptor 2, gene symbol Clec4a4), predominantly expressed on conventional type 2 dendritic cells (cDC2) in the mouse spleen, thymus, lymph node, and Peyer's patch. DCIR2+ DCs are involved in antigen presentation, suppression of autoimmunity, T cell priming modulation, metabolic inflammation, and tolerance induction.

• Regulation and Disease Association:
  The expression of DCIR2/33D1 is upregulated by GM-CSF and downregulated by IL-4 in experiments using bone marrow-derived DCs. DCs rich in DCIR2 ameliorate autoimmune and inflammatory conditions in experimental models, including encephalomyelitis, melanoma, and diabetes.

• Complementation Experiments:
  The removal of DCs with 33D1 and complement ablates stimulatory function in spleen cell preparations, which can be restored by re-adding small numbers of purified DCs, confirming the essential role of DCs in antigen-specific T cell activation.

These findings establish 33D1 as a foundational tool in immunology for dissecting dendritic cell function and their roles in immune modulation, tolerance, and disease models.