GLOSSARY
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ICAM-2 (CD102) #
Alternative names: ICAM-2, LY-60
In humans and in mice, ICAM-2 can be found on the surface of: T cells, B cells, macrophages/monocytes, endothelial cells
Ligands and associated molecules: LFA-1, CD11b/CD18, Integrin ɑLβ2, MAC-1
Function: cell adhesion, costimulation, lymphocyte recirculation
Additional information: ICAM-2 is also known as CD102. CD102 facilitates the interaction between T cells and B cells during lymphocyte development. CD102 mediates the cell adhesive interactions necessary for an antigen-specific immune response, and other cellular interactions important for immune surveillance and response.
ICOS (CD278) #
Alternative names: MGC39850, AILIM, Ly115, H4
In humans and in mice, ICOS can be found on the surface of: T cells
Ligands and associated molecules: CD275 (B7-H2)
Function: costimulation, T cell development
Additional information: ICOS is also known as CD278. CD278 cell surface expression is upregulated upon T cell activation. Upon binding by CD275, CD278 induces T cell proliferation and the production of cytokines for Th2 differentiation.
ICOS Ligand (CD275) #
Alternative names: B7-H2, B7RP1, LICOS, B7RP-1, KIAA0653, ICOSLG
ICOS Ligand can be found on the surface of:
- Human: T cells, B cells, dendritic cells, macrophages/monocytes, granulocytes
- Murine: B cells, dendritic cells, macrophages/monocytes
Ligands and associated molecules: CD278 (ICOS)
Function: costimulation, T cell and B cell activation, T cell proliferation
Additional information: ICOS Ligand (ICOSL) is also known as CD275. CD275 is part of the B7 family. Upon ligand binding on B cells, CD275 promotes B cell differentiation, activation, and antibody secretion. Upon ligand binding on T cells, CD275 promotes T cell activation, proliferation, differentiation, and cytokine production.
IL-12Rβ1 (CD212) #
Alternative names: Interleukin-12 receptor β1 chain, CD212b1
IL-12Rβ1 can be found on the surface of:
- Human: T cells, B cells, NK cells
- Murine: T cells, B cells, dendritic cells, NK cells, macrophages/monocytes
Ligands: IL-12, IL-23
Associated molecules: IL-12Rβ2, IL-23R, Tyk2
Function: IL-12 and IL-23 receptor, signal transduction
Additional information: IL-12Rβ1 is also known as CD212. On its own, CD212 is a low-affinity receptor for IL-12. When CD212 associates with IL-12Rβ2, it becomes a high-affinity receptor for IL-12. The IL-12/IL-12R pathway is critical for IFNγ production and subsequent immune activation, including NK cell activation and Th1 cell differentiation. When IL-12 binds to the receptor, CD212 associates with Tyk2 while IL-12Rβ2 associates with JAK2 as part of the signaling pathway. CD212 is also a receptor for IL-23 which is a cytokine involved in inflammation and Th17 immunity.
IL-15R (CD215) #
Alternative names: IL15RA
In humans and in mice, IL-15R can be found on the surface of: T cells, B cells
Ligands: IL-15
Associated molecules: CD132, CD122
Function: Receptor for interleukin 15
Additional information: IL-15R is also known as CD215. CD215 interacts with CD132 and CD122 to form the receptor for IL-15. IL-15 is critical for formation and survival of CD8+ memory cells.
IL-18Rβ (CD218b) #
Alternative names: IL18RAP, IL-1R7, CDw218b
IL-18Rβ can be found on the surface of:
- Human: T cells, B cells, NK cells, dendritic cells, granulocytes
- Murine: T cells, NK cells, dendritic cells, macrophages/monocytes, endothelial cells
Ligands: IL-18
Associated molecules: CD218a
Function: Receptor for IL-18
Additional information: IL-18Rβ is also known as CD218b. CD218b associates with CD218a to form the heterodimeric receptor for IL-18. CD218b is the signal-transducing chain of the receptor complex, whereas CD128a is the ligand-binding chain. CD218a has a low affinity to IL-18, but when associated with CD218b, the binding affinity is increased. The IL-18 signal pathway is critical for the production and release of various cytokines and expression of adhesion molecules involved in the Th1 and Th2 inflammatory response.
Further reading:
IL-21R (CD360) #
IL-21R can be found on the surface of:
- Human: T cells, B cells, NK cells, dendritic cells, granulocytes, macrophages/monocytes, stem cells
- Murine: T cells, B cells
Ligands: IL-21
Associated molecules: CD132, JAK-1, JAK-3 and STAT
Function: Receptor for IL-21
Additional information: IL-21R is also known as CD360. CD360 is a type I cytokine receptor and forms a receptor complex with the common gamma chain cytokine receptor subunit (CD132). Binding of IL-21 activates the Janus-kinase pathway and downstream, the STAT signaling pathway. The IL-21/IL-21R pathway is crucial for increasing T cell differentiation and proliferation, NK cell differentiation and cytotoxicity, and differentiating B cells into antigen-specific memory B cells.
IL-2Rα (CD25) #
Alternative names: Tac antigen, p55, TCGFR, Ly-43
In humans and mice, IL-2Rα can be found on the surface of: T cells, B cells, NK cells, macrophages/monocytes
Ligands: IL-2 (interleukin-2)
Associated molecules: CD122
Function: IL-2 receptor
Additional information: IL-2Rα is also known as CD25. Along with other markers, CD25 is a surface marker used to identify regulatory T cells (Tregs). CD25 is the alpha chain of the IL-2 receptor and forms together with CD122 and CD132 to form high-affinity IL-2 receptors.
IL-2Rβ (CD122) #
Alternative names: p70-75, IL-2 and IL-15 receptor β chain
In humans and in mice, IL-2Rβ can be found on the surface of: T cells, B cells, NK cells, macrophages/monocytes
Ligands: IL-2, IL-15
Associated molecules: CD25, CD132, Syk, Lck, Jak1, Stat5
Function: β subunit of the IL-2 and IL-15 receptor, Signal transduction
Additional information: IL-2Rβ is also known as CD122. CD122 is the beta subunit of the IL-2 receptor and IL-15 receptor. Both IL-2 and IL-15 are critical cytokines in the signaling pathways that lead to naive and memory T cell development and effector functions. Recent research has focused on blocking CD122 to promote immune tolerance to transplants. The CD122/IL-15 and CD122/IL-2 pathways play a definitive role in inducing NK cell maturation and maintaining NK cell cytotoxic activity against infection. CD122 expression is upregulated on the surface of NK cell progenitors in preparation for differentiation/maturation.
IL-3RA (CD123) #
Alternative names: IL3R, IL3RAY, IL3RX, IL3RY, MGC34174, hIL-3Ra
In humans and in mice, IL-3RA can be found on the surface of: dendritic cells, endothelial cells, granulocytes, macrophages/monocytes, stem cells/precursors
Ligands: IL-3
Associated molecules: CD131
Function: Interleukin-3 receptor
Additional information: IL-3RA is also known as CD123. CD123 is the IL-3-specific alpha subunit of the IL-3 receptor and forms a complex with CD131 (the common beta chain). IL-3 signals through the heterodimeric IL-3 receptor complex and stimulates proliferation and differentiation.
IL-4 receptor ɑ chain (CD124) #
Alternative names: IL4RA, IL4R
IL-4 receptor ɑ chain can be found on the surface of:
- Human: T cells, B cells, stem cells/precursors, macrophages/monocytes, epithelial cells
- Murine: T cells, B cells, dendritic cells, granulocytes, epithelial cells
Ligands: IL-4, IL-13
Associated molecules: CD132, Jak1, Fes, Stat6, IRS-2
Function: Interleukin-4 and Interleukin-13 receptor
Additional information: IL-4 receptor ɑ chain is also known as CD124. CD124 is the alpha chain of the IL-4 and IL-13 receptors. CD124 interacts with CD132 to form a functional receptor. IL-4 or IL-13 signaling pathways are important for IgE production, differentiation of Th2 cells, alternative activation of B cells, and the regulation of CD20 levels on B cells.
IL-7Rα (CD127) #
Alternative names: p90
In humans and mice, IL-7Rα can be found on the surface of: T cells, precursor cells, macrophages/monocytes
Function: receptor for IL-7 and thymic stromal lymphopoietin (TSP), T cell maturation and proliferation.
Ligands: IL-7, TSLP
Associated molecules: CD132, Fyn, lyn, Jak1, P13-Kinase, Lck
Additional information: IL-7Rα is also known as CD127. CD127, together with CD132, forms the IL-7 receptor. Binding of IL-7 to the IL-7 receptor causes a signal cascade that stimulates the first stage of thymic T cell development by protecting from apoptosis and promoting VDJ TCR recombination. CD127 signaling is crucial for the survival of mature T cells within the periphery. CD127 transcription and expression is homeostatically controlled in a negative feedback loop by IL-7 levels. CD127, together with the TSLP receptor chain (TSLPR or CRLF2), forms a high-affinity receptor for TSLP, which plays a pivotal role in T cell maturation, promoting T cell proliferation, driving T helper cytokine production, and inducing dendritic cell polarization.
Further reading:
Immune Checkpoint Blockade (ICB) #
A type of immunotherapy aimed at blocking interactions involving important regulatory molecules on immune cells (immune checkpoints) that modulate immune responses. Interactions between these molecules can activate or suppress an immune response. Key examples of immune checkpoint molecules include CTLA-4, PD-1, PD-L1, TIM3, LAG3, OX40, GITR, and others. Blockade of interactions between these molecules and their ligands have dramatically improved anti-cancer immunotherapy by enhancing anti-cancer immune responses. Additional immune checkpoint molecules have been identified and are being studied to assess the clinical benefit of blocking their interactions.
Immune Checkpoints #
A group of molecules that regulate immune responses. Immune checkpoints can be present on T cells, antigen-presenting cells, and tumor cells in the tumor bed and periphery. Interactions between the molecules can activate or suppress an immune response. Key examples of immune checkpoint molecules include CTLA-4, PD-1, PD-L1, TIM3, LAG3, OX40, GITR, and others.
Immune Epitope Database and Analysis Resource (IEDB) #
A searchable compilation of immune response-related antigens and epitopes relevant to infectious disease, allergy, autoimmunity, and transplantation in humans and other species. IEDB also provides tools to assist in predicting and analyzing immune epitopes. IEDB is supported by the National Institute of Allergy and Infectious Diseases.
International ImMunoGeneTics information system® (IMGT) #
An access point and resource of sequence, structure, antibodies, and web resources relevant for studying B and T cell receptors, major histocompatibility (MHC) molecules, the immunoglobulin and major histocompatibility superfamily, and related proteins of the immune system of vertebrates and invertebrates. Visit IMGT here.
