Concanavalin A (Con A), a mannose/glucose-binding lectin isolated from Jack beans (Canavalia ensiformis), is a well-known T cell mitogen that can activate the immune system, recruit lymphocytes and elicit cytokine production. In addition to its mitogenic activity, ConA can induce programmed cell death via mitochondria-mediated apoptosis and autophagy. Interestingly, ConA has been reported to activate NFAT (nuclear factor of activated T cells), a family of transcription factors that are important in the development and function of the immune system, including T cell receptor (TCR) engagement. Specifically, binding of ConA triggers cross-linking of the TCR complex leading to T cell activation.

Concanavalin A (Con A) has 4 subunits and a molecular weight of 104 kDa. Con A is the most widely used lectin and has broad applicability. For example, immobilized Con A has been used in affinity chromatography purifications of a wide variety of glycoproteins and cellular structures.