trastuzumab Humanized antibody to HER-2/neu used in treatment of breast cancer.
TRECs See T-cell receptor excision circles.
TRIF An adaptor protein that alone is involved in signaling by TLR-3, and that when paired with TRAM, functions in signaling by TLR-4.
TRIKA1 A complex of the E2 ubiquitin ligase UBC13 and cofactor Uve1A, that interacts with TRAF6 in forming the K63 polyubiquitin signaling scaffold in TLR signaling downstream of MyD88.
TRIM21 (tripartite motif-containing 21) A cytosolic Fc receptor and E3 ligase that is activated by IgG and can ubiquitinate viral proteins after an antibody-coated virus enters the cytoplasm.
TRIM25 An E3 ubiquitin ligase involved in signaling by RIG-I and MDA-5 for the activation of MAVS.
tropism The characteristic of a pathogen that describes the cell types it will infect.
TSC Protein complex that acts as a GTPase-activating protein (GAP) for Rheb in its non-phosphorylated state. TSC is inactivated when phosphorylated by Akt.
TSLP Thymic stroma-derived lymphopoietin. A cytokine thought to be involved in promoting B-cell development in the embryonic liver.
tumor necrosis factor-α See TNF family.
tumor rejection antigens Antigens on the surface of tumor cells that can be recognized by T cells, leading to attack on the tumor cells. TRAs are peptides of mutant or overexpressed cellular proteins bound to MHC class I molecules on the tumor-cell surface.
type 1 diabetes mellitus Disease in which the β cells of the pancreatic islets of Langerhans are destroyed so that no insulin is produced. The disease is believed to result from an autoimmune attack on the β cells. It is also known as insulin-dependent diabetes mellitus (IDDM), because the symptoms can be ameliorated by injections of insulin.
type 1 immunity Class of effector activities aimed at elimination of intracellular pathogens.
type 2 immunity Class of effector activities aimed at elimination of parasites and promoting barrier and mucosal immunity.
type 3 immunity Class of effector activities aimed at elimination of extracellular pathogens such as bacteria and fungi.
type I interferons The antiviral interferons IFN-α and IFN-β.
type II interferon The antiviral interferon IFN-γ.
type III secretion system (T3SS) Specialized appendage of Gram-negative bacteria used to aid infection of eukaryotic cells by direct secretion of effector proteins into their cytoplasm.
tyrosinase Enzyme in melanin synthesis pathway and frequently a tumor rejection antigen in melanoma.
tyrosine phosphatases Enzymes that remove phosphate groups from phosphorylated tyrosine residues on proteins. See also CD45.
tyrosine protein kinases   Enzymes that specifically phosphorylate tyrosine residues in proteins. They are critical in the signaling pathways that lead to Tand B-cell activation.
UBC13 See TRIKA1.
ubiquitin A small protein that can be attached to other proteins and functions as a protein interaction module or to target them for degradation by the proteasome.
ubiquitin ligase Enzyme that attaches ubiquitin covalently to exposed lysine residues on the surfaces of other proteins.
ubiquitin–proteasome system (UPS) A quality control system in the cell that involves K48-linked ubiquitination of target proteins that are then recognized by the proteasome for degradation.