Selection of Unique Markers for Mouse Cells

When reviewing literature, you may come across references to distinctive mouse markers such as F4/80, NK1.1, CD90.1/CD90.2, CD45.1/CD45.2. Are you puzzled by these unique markers? Why do some mouse use one marker while others use a different one? How should these markers be chosen? Additionally, what is the significance of mouse CD16/32 surface Fc receptors and how should they be blocked? Let's explore these questions together.

1. F4/80 - Mature Mouse Macrophage Marker

F4/80, also known as EMR1 or Ly71, is a widely used marker for mouse macrophages. It is expressed in various mature macrophage populations, including Kupffer cells, Langerhans cells, microglia, and macrophages in the peritoneum, lungs, intestines, thymus, red pulp of the spleen, and bone marrow stroma. F4/80 serves as a marker for mature mouse macrophages, and in flow cytometry, using F4/80+CD11b+ can distinguish them from other monocytes, as shown below ：

Detection of Mouse Peritoneal Macrophages

2. CD16/32 - Cell Surface Fc Receptors

CD16 represents low-affinity IgG Fc receptor III (FcR III), and CD32 is Fc receptor II. They can bind to antibody-antigen immune complexes and mediate adaptive immune responses. CD16/32 is expressed on B cells, monocytes/macrophages, NK cells, granulocytes, mast cells, and dendritic cells. When detecting mouse samples, using purified anti-mouse CD16/32 monoclonal antibody as an Fc receptor blocker is recommended. Generally, with a reaction volume of 100 μL, 10^6 cells, and adding 0.5-1 μg of Purified Anti-Mouse CD16/32 Antibody, incubating at room temperature for 10 minutes effectively blocks mouse Fc receptors, as following: 

Impact of FcR on Mouse Peritoneal Macrophage Detection

3. CD49b/NK1.1 - Mouse NK Cell Markers

CD49b and NK1.1 are markers for identifying mouse NK cells. Depending on the mouse strain, one of these markers is chosen. For instance, CD49b (DX5) is used for BALB/c mice, while NK1.1 is used for C57BL/6 mice. Analysis involves gating CD3-CD49b+ or CD3-NK1.1+ cells. The results of NK cell detection in C57BL/6 mice are depicted in below: 

Detection of C57BL/6 Mouse NK Cells

4. Differences between Mouse CD90 and CD90.1/CD90.2

Mouse CD90 protein has two alleles, Thy1.1 (CD90.1) and Thy1.2 (CD90.2), differing at the 108th amino acid position. CD90 is expressed on hematopoietic stem cells, neurons, all thymocytes, and peripheral T cells. Mouse strains expressing CD90.1 include AKR, BDP, MA/MyJ, while those expressing CD90.2 include BALB/c, CBA/J, C3H/He, C57BL/-, DBA, NZB/-, among others. CD90.1 and CD90.2 can be utilized for cell transfer experiments to study cell proliferation, differentiation, and distribution.

5. Differences between Mouse CD45 and CD45.1/CD45.2

Mouse CD45 protein has two alleles, CD45.1 and CD45.2. CD45.1 is found in mouse strains like FVB, RIII, SJL/J, while CD45.2 is found in AKR, BALB/c, CBA/Ca, CBA/J, C3H/He, C57BL, C57BR, C57L, C58, DBA/1, DBA/2, NZB, SWR, 129, and others. CD45.1 and CD45.2 are used for cell transfer experiments similar to CD90.1 and CD90.2 to study cell characteristics.

In summary, F4/80 is specific to mouse macrophages, mouse surface FcRs can be effectively blocked with purified anti-mouse CD16/32 antibodies, and different markers might be chosen for cell identification based on the mouse strain. If you have further questions about other mouse markers used in flow cytometry, feel free to leave us a message, and we will get back to you ASAP.