Human CD2 is also referred as LFA-2 (leukocyte function-associated antigen-2), which belongs to the immunoglobulin supergene family. CD2 is a monomeric transmembrane glycoprotein with a weight of 45–50 kDa and binds CD58, CD48, or CD59. It consists of two extracellular Ig-like domains (one V-like and one C-like) and a proline-rich cytoplasmic tail. CD2 is commonly expressed on most mature peripheral T cells, NK-cells, and a subset of thymic B-cells during human thymocyte development. CD2 is crucial in T-cell activation, T- or NK-mediated cytolysis, apoptosis in activated peripheral T-cells, and the production of cytokines by T-cells. CD2 is an excellent pan-T-cell marker. The low expression level of CD2 is thought to associated with some of the T-lymphoid malignancies, particularly peripheral T-cell lymphomas. The epidermal growth factor receptor (EGFR) is over-expressed in various human epithelial tumors usually due to the gene amplification. EGFR gene amplification in tumors frequently contain its rearrangements and among them, the most common extracellular domain mutation is receptor variant III, EGFRvIII (also known as de2-7EGFR or DEGFR). The molecular mass of EGFRvIII is approximately 145 kDa and this genetic change of tumor-specific mutation results from a deletion of 267 amino acids spanning exons 2-7 of the EGFR gene. These consequences make the variant EGFRvIII incapable of binding known ligand. It is expressed in a majority of patients with glioblastoma multiforme. And the evidence shows aberrant EGFRvIII signaling is important for driving tumor progression.