CD58 Antibody, FITC

CD58, also known as Lymphocyte Function-Associated Antigen-3 (LFA-3), is a glycoprotein member of the immunoglobulin superfamily. It plays a crucial role in the immune response by facilitating cell adhesion and enhancing antigen-specific T-cell activation through its interaction with CD2 on T lymphocytes .

CD58 is a membrane glycoprotein with a molecular weight ranging from 55 to 70 kDa. It exists in two isoforms:

1. Transmembrane Isoform: This form has a cytoplasmic domain and is anchored in the membrane.
2. Glycosylphosphatidylinositol (GPI)-Linked Isoform: This form is anchored in the membrane via a GPI tail .

Both isoforms can be expressed on the same cell type, except for erythrocytes, which only express the GPI-linked isoform .

CD58 has a wide tissue distribution and is expressed on both hematopoietic and non-hematopoietic cells, including endothelial cells, fibroblasts, erythrocytes, platelets, monocytes, a subset of lymphocytes, and bone marrow cells . There are approximately 5,000 CD58 molecules on each erythrocyte .

The primary function of CD58 is to mediate cell adhesion by binding to CD2 on T lymphocytes. This interaction enhances antigen-specific T-cell activation and plays a role in cell-mediated cytotoxicity . CD58 is also involved in the facilitation of antigen-specific recognition, which is critical for the immune response .

The monoclonal antibody against human CD58, derived from mouse, is purified from tissue culture supernatant or ascites by affinity chromatography. The antibody is then conjugated with Fluorescein Isothiocyanate (FITC) under optimal conditions, and unreacted FITC is removed . FITC is a fluorophore that emits green fluorescence when excited by light, making it useful for flow cytometry and other fluorescence-based assays .

The FITC-conjugated mouse anti-human CD58 antibody is routinely used in flow cytometry to analyze the expression of CD58 on various cell types . It is also used in research to study cell adhesion, T-cell activation, and immune response mechanisms .

The antibody should be stored undiluted at 4°C and protected from prolonged exposure to light. It should not be frozen. The storage buffer typically contains bovine serum albumin (BSA) and sodium azide as a preservative .

Sodium azide, present in the storage buffer, is highly toxic and can form explosive compounds under acidic conditions. It should be diluted in running water before disposal to prevent accumulation in plumbing .