Anti-Mouse CD19 [Clone 1D3] — Purified in vivo GOLD™ Functional Grade

In in vivo mouse studies, clone 1D3 is primarily used as a monoclonal antibody targeting mouse CD19, a B cell–specific marker, and as the antigen-binding domain for constructing mouse-specific anti-CD19 chimeric antigen receptor (CAR) T cells.

• As a monoclonal antibody (mAb): 1D3 can be administered directly to mice for selective depletion of B cells or to study B cell function and depletion in disease models such as lymphoma. The 1D3 mAb has demonstrated noncurative antilymphoma activity in vivo and can mediate antibody-dependent cell-mediated cytotoxicity against murine lymphoma cells.
• As a CAR component: The single-chain variable fragment (scFv) derived from 1D3 is commonly used in constructing murine anti-CD19 CARs, enabling mouse T cells to specifically recognize and eliminate CD19^+^ B cells and B-cell malignancies in mouse models. CAR-T cells expressing 1D3-based CARs have shown efficacy in eradicating murine lymphoma and depleting normal B cells, resulting in both tumor clearance and B cell aplasia. 1D3-derived CAR-T cells are generated by transducing mouse T cells with retroviral or lentiviral vectors encoding the 1D3 scFv fused to mouse costimulatory and signaling domains, then adoptively transferring these engineered T cells into tumor-bearing or disease-model mice.

Experimentally, 1D3 is used in:

• Inducing B cell depletion by systemic administration of the mAb (for immunophenotyping, immunotherapy, and studying B cell biology).
• Generating and testing murine CAR-T cells for anti-lymphoma efficacy, B cell ablation, and autoimmunity models.
• In vitro as a blocking antibody or detection reagent in B cell assays and flow cytometry.

The choice of 1D3, particularly in CAR constructs, is driven by its specificity for mouse CD19 and effectiveness in mediating B cell and B-cell–tumor targeting without cross-reactivity with human CD19.

Summary Table:

This dual utility makes 1D3 a standard tool for mouse B cell targeting and modeling B cell–directed therapies.

The correct storage temperature for sterile packaged clone 1D3 (Anti-mouse CD19 monoclonal antibody) depends on the intended storage duration:

• For long-term storage (up to 12 months), keep it at -20°C to -70°C in a manual defrost freezer and avoid repeated freeze-thaw cycles.
• For short-term storage (up to 1 month), it may be kept at 2–8°C (standard refrigerator temperature) as supplied.
• For ready-to-use, fluorochrome-conjugated forms (such as for flow cytometry), manufacturers may recommend 2–8°C storage and specifically advise not to freeze.

Always refer to the product's datasheet or label upon receipt, as certain conjugates or formulations can have unique requirements. Protect from light and store as indicated to maintain sterility and functionality.

Commonly used antibodies or proteins that are combined with 1D3 (which typically refers to the anti-mouse CD19 monoclonal antibody clone 1D3) in the literature include anti-mouse B220 (clone RA3-6B2), anti-mouse CD22 (clone Cy34.1), and anti-rat ? light chain (clone MAR 18.5).

These antibodies are often used in combination with 1D3 for the following purposes:

• B cell depletion protocols: 1D3 is sometimes insufficient alone for maximum B cell depletion; thus, protocols frequently combine it with anti-B220, anti-CD22, and anti-rat ? light chain antibodies to increase efficiency and specificity.
• Phenotyping B cell populations: Other B cell markers such as B220 (CD45R), CD22, and additional lineage markers are commonly used with 1D3 in multicolor flow cytometry panels to distinguish between different stages or subtypes of B cells.

Frequently used combinations (summarized):

In summary, the most commonly cited antibodies used with 1D3 are those targeting B220, CD22, and ? light chain, especially in experiments involving mouse B cells. Their primary use is to increase the specificity and effectiveness of B cell targeting for either depletion protocols or detailed B cell phenotyping.

Clone 1D3 is a monoclonal antibody directed against mouse CD19, a protein expressed on the surface of B cells. Here are the key findings from citations in scientific literature related to clone 1D3:

1. Epitope Overlap and Competition Assays:

   • Clone 1D3 has been used in competition assays with other anti-mouse CD19 clones, demonstrating overlapping epitopes. This suggests that different clones may target similar regions on the CD19 antigen, which can affect their binding characteristics and effectiveness in various applications.

2. Isolation and Characterization:

   • The antibody sequence of the 1D3 clone was isolated from monoclonal hybridoma cells. This involved RNA extraction, cDNA conversion, and nested PCR to sequence the heavy and light chains of the antibody.
   • The clone was kinetically characterized using surface plasmon resonance (SPR) on a Biacore system to assess its binding properties to mouse CD19-expressing cells.

3. CAR T-Cell Applications:

   • Clone 1D3 has been incorporated into chimeric antigen receptor (CAR) T-cell structures for targeting mouse CD19-expressing cells. This involves modifying T cells to recognize and attack B cells expressing CD19, which is relevant for B cell malignancies and autoimmune diseases.
   • In vitro studies have shown that 1D3-based CAR T cells can effectively target and eliminate A20 cells, a murine B cell lymphoma line expressing CD19.

4. Blocking Antibody Assays:

   • The 1D3 clone has been used as a blocking antibody in assays to inhibit the interaction between CAR T cells and CD19-expressing target cells. This demonstrates its specificity and utility in studying B cell interactions.

In summary, clone 1D3 is a valuable tool for studying mouse CD19 expression and for developing therapeutic strategies involving CAR T cells against B cell targets.