How can CD45 antibodies for mice become a core tool in universal blood cancer therapies and immunology research?

I. What key role does CD45 play in the immune system?

CD45, fully named Protein Tyrosine Phosphatase Receptor Type C (PTPRC), is also known as Leukocyte Common Antigen (LCA). As a transmembrane glycoprotein, its molecular weight ranges from 180 to 220 kDa. This molecule is expressed in all hematopoietic lineage cells except mature erythrocytes, including T cells, B cells, natural killer cells, monocytes, macrophages, granulocytes, and their various precursor cells. The core biological function of CD45 lies in its intracellular protein tyrosine phosphatase activity, which is crucial for immune cell signal transduction. Specifically, CD45 positively regulates the initiation of T cell receptor (TCR) and B cell receptor (BCR) signaling pathways by dephosphorylating and activating Src family kinases (such as Lck and Fyn in T cells, Lyn in B cells, etc.), serving as an indispensable molecular switch for lymphocyte activation. Additionally, CD45 participates in regulating cytokine receptor signaling pathways and influences lymphocyte survival. Dysfunction of CD45 is closely associated with various immune deficiencies, autoimmune diseases, and hematologic malignancies.

II. What are the core challenges and innovative strategies in CD45-targeted therapy?

Given that CD45 is widely expressed on almost all hematopoietic cells, it has become an attractive target for developing universal therapies for hematologic malignancies. For example, CD45-targeted CAR-T cell therapy could theoretically eliminate all malignant hematopoietic cells. However, the greatest challenge lies in the fact that CD45 is also highly expressed on normal T cells (including CAR-T cells themselves) and hematopoietic stem cells (HSCs). If unmodified CD45 CAR-T cells are used directly, it would trigger a "fratricide" effect—where CAR-T cells kill each other—while also destroying the patient's normal hematopoietic system, leading to fatal myelosuppression. Recent studies have proposed an innovative solution: using CRISPR-mediated base editing technology to modify the epitopes of CD45 proteins on CAR-T cells and HSCs. The edited CD45 molecules retain their normal physiological functions but have altered key antigen epitopes, enabling them to evade CAR recognition. This lays the foundation for a "universal" treatment paradigm: first infusing edited, "stealth" CAR-T cells that are invisible to their own CD45 to eliminate tumors, then transplanting similarly edited HSCs to rebuild normal hematopoietic and immune systems, thereby achieving systemic treatment of hematologic malignancies.

III. What is the research value of the expression profiles of different CD45 isoforms?

Another important feature of CD45 is the existence of multiple isoforms, determined by alternative splicing of its gene (located on chromosome 1 in mice). Specific exons (corresponding to human exons 4, 5, and 6) can be selectively included or excluded, producing subtypes such as CD45RA, CD45RB, CD45RC, and CD45RO. These isoforms exhibit differential expression in immune cells at different developmental stages and subsets. For example, naïve T cells primarily express the RA isoform of CD45, while memory T cells mainly express CD45RO. Therefore, specific antibodies targeting different epitopes of mouse CD45 (such as anti-CD45R, anti-CD45RB, etc.) have become key tools for precisely identifying and distinguishing immune cell subsets (e.g., T cells, B cells, monocytes) and their activation states via flow cytometry. This isoform-based cell typing has broad applications in basic immunology research, disease model analysis, and immunophenotypic diagnosis of hematologic malignancies.

IV. What are the core applications of mouse CD45 antibodies in basic and translational research?

Mouse CD45 antibodies are indispensable reagents in immunology research and preclinical drug development. Their main applications include:

1. Immune cell identification and sorting: As a pan-leukocyte marker, anti-mouse CD45 antibodies are fundamental for efficiently isolating and enriching all leukocytes from complex tissues (e.g., spleen, lymph nodes, bone marrow, tumors) in flow cytometry or immunomagnetic bead sorting.

2. Fine subtyping of cell populations: Combined with antibodies recognizing different CD45 isoforms (e.g., CD45R) or other surface markers (e.g., CD3, CD4, CD8, CD19, CD11b), they enable more precise subset classification and functional state analysis of T cells, B cells, and myeloid cells.

3. Disease model analysis: In mouse models of autoimmune diseases, infections, transplant rejection, and hematologic malignancies, CD45 antibodies are used to dynamically monitor the quantity, proportion, and infiltration of different immune cell populations in peripheral blood and target organs, serving as a core method for evaluating disease progression and immune responses.

4. Support for targeted therapy research: In developing the aforementioned CD45-targeted therapies (e.g., CAR-T, antibody-drug conjugates), anti-mouse CD45 antibodies can validate target expression, assess target cell clearance before and after treatment, and analyze immune reconstitution, making them critical tools for preclinical efficacy and safety evaluation.

V. Which manufacturers provide mouse CD45 antibodies?

Hangzhou Start Biotech Co., Ltd. has independently developed the "Alexa Fluor® 647 Mouse Anti-Rat CD45 Antibody (S-R591)" (Catalog No.: S0B8252), a ready-to-use flow cytometry detection antibody with high fluorescence brightness, excellent photostability, and outstanding specificity. This product uses highly purified mouse anti-rat CD45 monoclonal antibodies labeled with Alexa Fluor® 647 fluorescent dye through optimized processes. It efficiently and specifically binds to rat CD45 molecules (leukocyte common antigen), enabling sensitive and accurate identification and sorting of various leukocytes in multicolor flow cytometry (FACS) analysis. It is a core tool for rat immunology research and disease model analysis.

Technical Support: We provide detailed technical parameters for this product, including recommended concentrations, applicable sample types (whole blood, tissue suspensions), and its core position and combination suggestions in multicolor flow panels. Our technical team offers professional consultation on experimental design and data analysis.

Hangzhou Start Biotech Co., Ltd. is committed to providing high-performance, high-quality multicolor flow cytometry detection antibodies for rat disease model immunology research. For more information about the "Alexa Fluor® 647 Mouse Anti-Rat CD45 Antibody" (Catalog No. S0B8252), to obtain technical documentation, or to request a sample trial, please feel free to contact us.

Product Information

Disclaimer: This article partially utilizes artificial intelligence assistance in its creation. If any content involves copyright or intellectual property issues, please let us know and we promise to verify and remove it as soon as possible.

ANT BIO PTE. LTD. – Empowering Scientific Breakthroughs

At ANTBIO, we are committed to advancing life science research through high-quality, reliable reagents and comprehensive solutions. Our specialized sub-brands (Absin, Starter, UA) cover a full spectrum of research needs, from general reagents and kits to antibodies and recombinant proteins. With a focus on innovation, quality, and customer-centricity, we strive to be your trusted partner in unlocking scientific mysteries and driving medical progress. Explore our product portfolio today and elevate your research to new heights.