ICOSLG

Function

Ligand for the T-cell-specific cell surface receptor ICOS. Acts as a costimulatory signal for T-cell proliferation and cytokine secretion (PubMed:11007762, PubMed:11023515, PubMed:30498080). Also induces B-cell proliferation and differentiation into plasma cells. Could play an important role in mediating local tissue responses to inflammatory conditions, as well as in modulating the secondary immune response by co-stimulating memory T-cell function (By similarity). In endothelial cells, required for proper neutrophil transmigration in response to chemoattractants, such as CXCL8/IL8 or N-formyl-methionyl peptides (fMLP) (PubMed:30498080).

Involvement in disease

Immunodeficiency 119

IMD119

An autosomal recessive immunologic disorder characterized by childhood-onset of recurrent respiratory tract infections, susceptibility to chronic DNA-based viral infections, hypogammaglobulinemia, and panlymphopenia.

None

The disease may be caused by variants affecting the gene represented in this entry.

Sequence Similarities

Belongs to the immunoglobulin superfamily. BTN/MOG family.

Tissue Specificity

Expressed on peripheral blood B-cells and monocytes, as well as on monocyte-derived dendritic cells (at protein level).

Isoform 1

Widely expressed (brain, heart, kidney, liver, lung, pancreas, placenta, skeletal muscle, bone marrow, colon, ovary, prostate, testis, lymph nodes, leukocytes, spleen, thymus and tonsil).

Isoform 2

Detected only in lymph nodes, leukocytes and spleen. Expressed on activated monocytes and dendritic cells.

Cellular localization

• Cell membrane
• Single-pass type I membrane protein
• Isoform 2
• Cell membrane

Alternative names

CD275, B7H2, B7RP1, ICOSL, KIAA0653, ICOSLG, ICOS ligand, B7 homolog 2, B7-like protein Gl50, B7-related protein 1, B7-H2, B7RP-1

Database links

swissprot:O75144 entrezGene:23308 omim:605717

Other research areas

• Immunology & Infectious Disease