Preferred Label : Bispecific CD80-lgG4Fc-IL-2v Fusion Protein GI-101;
NCIt synonyms : Bispecific Fusion Protein GI-101;
NCIt definition : A bi-specific Fc fusion protein composed of the N-terminal extracellular domain (ECD)
of human CD80 (B7.1) fused to a human immunoglobulin G4 (IgG4) Fc fragment and linked
to an interleukin (IL)-2 variant (IL-2v) as a C-terminal moiety, with potential immunostimulatory,
immune checkpoint inhibitory and antineoplastic activities. Upon administration of
bispecific CD80-IgG4Fc-IL-2v fusion protein GI-101, the CD80 moiety targets and binds
to CTL-associated antigen 4 (CTLA4; CTLA-4) expressed on T-cells. This prevents the
binding of CTLA-4 to endogenous CD80, enables the binding of CD80 to CD28, which leads
to CD28-mediated signaling, and results in the activation of T-cells in the tumor
microenvironment (TME). This promotes T-cell activity. The IL-2 moiety may stimulate
a local immune response and activate natural killer (NK) cells and cytotoxic T-cells.
This may enhance the activity of neoantigen specific T-cells and potentiates the T-cell-mediated
immune response against tumor cells. CD80 is a co-stimulatory molecule expressed on
activated antigen presenting cells (APCs) that plays a key role in T-cell activation
upon binding to CD28 on T-cells. On the other hand, binding of CD80 to CTLA-4 prevents
CD80-CD28 engagement, thereby inhibiting T-cell activity and immune activation. CTLA-4
is a member of the immunoglobulin superfamily (IgSF) and an inhibitory molecule upregulated
by T-cells following T-cell activation. It plays a key role in the downregulation
of the immune system. IL-2v cannot bind to IL-2 receptor-alpha (CD25, IL2Ra) and does
not activate regulatory T-cells (Tregs).;
Molecule name : GI 101; GI-101;
NCI Metathesaurus CUI : CL1664640;
Origin ID : C181773;
UMLS CUI : C5557257;
Semantic type(s)
- concept_is_in_subset
- has_target
