THEMIS antibody

Background of THEMIS antibody

Thymocyte-expressed molecule involved in selection (THEMIS) is a protein coding gene that plays a regulatory role in positive and negative T-cell selection during late thymocyte development (1). THEMIS is located on human chromosome 6q22.33. It is a member of a new metazoan gene family and is required for completion of thymocyte positive selection (2). THEMIS contains a tandem repeat of a unique globular domain which includes cysteine motif that defines a family consisting of five uncharacterized vertebrae proteins that have orthologs in most animal species (2). THEMIS appears to be related to TCR signaling and, because it is quickly phosphorylated after TCR stimulation, it is necessary for optimal TCR-driven calcium mobilization as well as being necessary for activation of the ErK-Kinase (3).
Recently it was reported that THEMIS is essential for the transition of CD4+ CD8+ double-positive (DP) cells to MHC class I-restricted CD4- CD8+ and MHC class II-restricted CD4+ CD8- single positive (SP) cells (4) In agreement with these findings THEMIS deficient thymocytes showed defective positive selection which caused fewer thymocytes to reach maturation (5). In these mice, CD4SP thymocyte maturation was more severely affected than CD8SP due to the fact that sustained signaling is essential for CD4SP thymocyte development (6). A large percentage of THEMIS-deficient cells had a CD4(+)CD25(+)Foxp3(t) regulatory and CD62L(10)CD44(hi) memory phenotypes than compared to wild type of T cells (3). THEMIS is expressed in thymocytes between the Pre-T cell antigen receptor (pre-TCR) and positive selection checkpoints.
THEMIS is approximately a 77kDa protein (641 amino acids).