Anti-Human CD5 (Clone UCHT-2) – Purified in vivo Functional GOLD^TM Functional Grade

Clone UCHT-2 is a mouse anti-human CD5 monoclonal antibody commonly used in humanized mouse models to specifically target and study human CD5-positive T cells and B cells in vivo. Its primary use in these studies is to deplete, modulate, or trace human CD5-expressing immune cells, enabling analysis of human immune cell function, trafficking, or depletion within a mouse environment.

Essential context for in vivo mouse studies:

• UCHT-2 specifically recognizes human CD5, a 67 kDa transmembrane glycoprotein present on most human thymocytes, the majority of peripheral T cells, and a subset of B cells. This specificity allows researchers to interrogate human immune responses in mice engrafted with human hematopoietic or immune cells.
• In vivo applications include:
  • Depletion of human T cells: UCHT-2 can be administered to humanized mice in order to selectively eliminate human CD5+ T cells, helping to study their roles in immune responses, tolerance, or disease models (e.g. autoimmunity, graft-versus-host disease).
  • Cellular tracking and tissue localization: By labeling human CD5+ cells, researchers can analyze cell migration, tissue localization, and compartmentalization using flow cytometry or histology in mouse tissues.
  • Modulation of immune responses: The antibody may be used to alter functional states of human T cells in vivo, such as activation or inhibition, depending on experimental goals.
• Functional Grade Antibody Use: The product description from Leinco specifically mentions that UCHT-2 is available in a “Functional GOLD™” grade for in vivo studies, indicating it is purified and formulated to minimize adverse effects (such as endotoxin contamination) and maximize functional efficacy in live animal models.

Additional relevant information:

• UCHT-2 is a mouse IgG1 isotype.
• Species cross-reactivity is highly selective for human CD5—it does not cross-react with mouse CD5, making it ideally suited for distinguishing human cells in mouse models.
• Humanized mouse platforms, such as those described for studying human immunity and antibody responses, frequently use such antibodies to probe specific human leukocyte subsets in vivo for therapeutic and mechanistic studies.

In summary, UCHT-2 is used in vivo in mouse studies to identify, deplete, or modulate human CD5+ T and B cells in humanized mouse models, supporting investigations in immunology, cell therapy, and disease modeling.

The correct storage temperature for the sterile packaged clone UCHT-2 (Anti-Human CD5 antibody) is 2-8°C (35-46°F).

Storage Guidelines

Short-term Storage: The UCHT-2 clone should be stored at 2-8°C and remains stable for at least one week to four weeks at this temperature range, depending on the specific formulation. The antibody solution should be kept undiluted and protected from prolonged exposure to light.

Long-term Storage: For extended storage periods, the antibody can be aliquoted in working volumes without diluting and stored at -20°C. However, it's important to note that most sources specifically advise do not freeze for the standard formulations.

Important Storage Considerations

The antibody should be stored in tightly closed containers in a dry, cool environment. When storing in refrigerated conditions, avoid repeated temperature fluctuations by keeping the antibody in the back of the refrigerator rather than near the door. For fluorescent-conjugated versions (such as PE or APC conjugates), protection from light exposure is particularly important.

The UCHT-2 clone is typically formulated in phosphate-buffered solution with pH 7.2, containing preservatives like sodium azide, which helps maintain stability during storage.

The UCHT-2 antibody specifically targets CD5, a surface marker found on T cells and a subset of B cells. In the scientific literature, when UCHT-2 (anti-CD5) is used, it's commonly part of multicolor flow cytometry panels or immunophenotyping assays alongside several other antibodies and markers to distinguish and subclassify lymphocyte populations or analyze immune cell states.

Frequently used antibodies or proteins in combination with UCHT-2 include:

• Anti-CD3 (e.g., clone UCHT1): A pan-T cell marker used to broadly define mature T cells. Co-staining with anti-CD3 and anti-CD5 helps further resolve T cell populations and potential T cell abnormalities.
• Anti-CD19 or Anti-CD20: B cell markers; used to distinguish T cells (CD3?CD5?) from the subset of B cells that co-express CD5 (CD19?CD5?, often implicated in certain leukemias and lymphomas).
• Anti-CD4 and Anti-CD8: Markers for helper and cytotoxic T cell subsets, respectively, often used in multicolor panels with anti-CD5 to delineate T cell differentiation and subset frequencies.
• Anti-CD45: A pan-leukocyte marker for gating leukocytes and further refining analysis of T versus B cells in immunophenotyping studies.
• Anti-CD7, CD2, CD56: Additional T/NK cell-related markers that may be included depending on the research or clinical focus.
• Anti-CD22, CD79a/b: Used in some advanced phenotypic or functional screens, especially for B cell studies or bispecific antibody screening, as shown in high-throughput approaches identifying combinations like CD22 and CD79 for modulating B cell activation.

Typical applications using these combinations include:

• Flow cytometry for lymphocyte subset discrimination
• Immunohistochemistry for tissue analysis of lymphoid organs or pathology
• Advanced functional screens for therapeutic antibody target discovery and immune modulation studies

In summary, UCHT-2 (anti-CD5) is most commonly used in conjunction with major T and B cell markers—CD3, CD19, CD20, CD4, CD8, CD45—and, increasingly, with novel or functional markers like CD22 or CD79 in more specialized settings. This approach allows for detailed immune profiling in both basic research and clinical diagnostics.

Summary of Key Findings from Clone UCHT-2 (Anti-CD5 Antibody) in Scientific Literature

Clone UCHT-2 is a widely used monoclonal antibody against human CD5, a 67 kDa glycoprotein expressed on most T lymphocytes, thymocytes, and a subset of B lymphocytes. The antibody has been utilized in research and clinical diagnostics for several decades, with findings spanning immunophenotyping, hematological malignancies, and fundamental immunology.

Specificity and Cellular Localization

• T-cell specific staining: UCHT-2 specifically recognizes human CD5 and is routinely used to identify and characterize human T-lymphocytes in both peripheral blood and tissues.
• B-cell subpopulation reactivity: Importantly, UCHT-2 also reacts with a distinct subset of normal B-lymphocytes, particularly B-chronic lymphocytic leukemia (CLL) cells and some lymphomas.
• Absence on monocytes, granulocytes, and NK cells: The antibody does not stain these cell types, emphasizing its specificity for lymphocytes within the immune system.
• Differential staining intensity: Peripheral blood T-cells typically show strong staining, while thymic T-cells exhibit weaker staining with UCHT-2.

Applications in Research and Diagnostics

• Leukemia and lymphoma characterization: UCHT-2 has been instrumental in the classification of leukemias and lymphomas, particularly for distinguishing CD5+ B-cell malignancies, which are a key diagnostic feature in chronic lymphocytic leukemia.
• Flow cytometry validation: The antibody is validated for flow cytometry, with peripheral blood lymphocytes clearly differentiated by positive staining in flow cytometric profiles.
• Benchmark for other reagents: UCHT-2 is frequently used as a positive control in experimental settings, including the development of novel CD5-targeting reagents.

Technical Notes and Limitations

• Optimal dilution varies: Each investigator must titrate UCHT-2 to determine the best working dilution for their specific application, as optimal conditions can vary with experimental setup.
• Safety considerations: Some commercial preparations contain sodium azide, which is toxic and requires careful handling.

Molecular Insights

• CD5 ligand: CD72 has been identified as the natural physiological ligand for CD5, and UCHT-2 is a tool to study this interaction in immune regulation.
• B-cell polyreactivity: CD5+ B cells targeted by UCHT-2 are known for producing polyreactive antibodies, mostly IgM, which is significant in understanding innate-like B-cell responses.

Conclusion

Clone UCHT-2 is a highly specific and reliable antibody for the identification of human T lymphocytes and CD5+ B-cell subsets, with broad applications in research and clinical diagnostics—especially in hematological malignancy classification, immunophenotyping, and basic immunology studies. It remains a benchmark reagent for studying CD5 biology and its role in human immune cell populations.