CD4 Antibody, FITC

The CD4 molecule is a 55 kDa glycoprotein that belongs to the immunoglobulin superfamily. It is primarily expressed on the surface of T helper cells, a subset of T lymphocytes, as well as on thymocytes, macrophages, and dendritic cells. CD4 plays a crucial role in the immune system by acting as a co-receptor that enhances the interaction between T cells and antigen-presenting cells (APCs) through its binding to MHC class II molecules .

The GK1.5 monoclonal antibody specifically binds to the mouse CD4 (L3T4) differentiation antigen. This antibody is derived from rat and is of the IgG2b, κ isotype. The GK1.5 clone is widely used in research to identify and isolate CD4+ T cells from mouse tissues .

FITC is a fluorochrome that emits green fluorescence when excited by blue light (488 nm). The conjugation of FITC to the GK1.5 antibody allows for the detection of CD4+ cells using flow cytometry. This technique is essential for analyzing the expression patterns of CD4 on various cell populations, such as splenic leukocytes .

The Rat Anti-Mouse CD4, FITC antibody is primarily used in:

• Flow Cytometry: To analyze the expression of CD4 on T cells and other immune cells.
• Immunohistochemistry: For staining tissue sections to visualize CD4+ cells.
• Cell Sorting: To isolate CD4+ T cells for further functional studies.

The antibody should be stored undiluted at 4°C and protected from prolonged exposure to light. It should not be frozen, as this can affect its functionality. The storage buffer typically contains a protein stabilizer and sodium azide as a preservative .

When handling antibodies conjugated with FITC, it is important to avoid prolonged exposure to light to prevent photobleaching. Additionally, sodium azide, a common preservative in antibody solutions, can form highly toxic hydrazoic acid under acidic conditions. Therefore, it should be diluted in running water before disposal to avoid the accumulation of potentially explosive deposits in plumbing .