SIGLEC5 (Sialic Acid Binding Ig Like Lectin 5)
A CD33-related Siglec receptor modulating immune cell signaling, implicated in infectious diseases and cancer.
Gene Information Card
| Symbol | SIGLEC5 |
|---|---|
| Full Name | Sialic acid binding Ig like lectin 5 |
| Gene Type | Protein coding |
| Chromosomal Location | 19q13.41 |
| NCBI Gene ID | 8778 ncbi.nlm.nih.gov/gene/8778 |
| Ensembl ID | ENSG00000105372 |
| UniProt ID | O15389 |
| OMIM ID | 605821 |
| HGNC ID | 10875 |
| Aliases | CD33L2, OB-BP2, SIGLEC-5, CD170 |
Description
SIGLEC5 encodes a type I transmembrane protein belonging to the sialic acid-binding immunoglobulin-like lectin (Siglec) family. It is primarily expressed on immune cells, particularly neutrophils and monocytes, and functions as an inhibitory receptor through immunoreceptor tyrosine-based inhibitory motifs (ITIMs). SIGLEC5 recognizes sialic acid-containing glycans on cell surfaces and pathogens, modulating immune responses. It has been implicated in bacterial infections (e.g., group B Streptococcus) and various cancers.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Group B Streptococcus infection | SIGLEC5 binds to sialic acid on the bacterial capsule, dampening neutrophil activation and promoting immune evasion. | PMID: 15123802; NCBI Gene |
| Acute myeloid leukemia (AML) | SIGLEC5 is overexpressed on AML blasts, contributing to immune suppression and poor prognosis. | PMID: 25009279; COSMIC |
| Chronic lymphocytic leukemia (CLL) | SIGLEC5 expression on CLL cells may modulate tumor microenvironment interactions. | PMID: 23509157; COSMIC |
| Sepsis | SIGLEC5 engagement by pathogens may exacerbate immunosuppression during sepsis. | PMID: 26937021; NCBI Gene |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Whole blood | 11.2 | High |
| Spleen | 5.3 | Medium |
| Bone marrow | 4.8 | Medium |
| Lung | 2.1 | Low |
| Liver | 0.8 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| THP-1 (monocytic leukemia) | 15.4 | High expression |
| HL-60 (promyelocytic leukemia) | 12.7 | High expression |
| K-562 (chronic myelogenous leukemia) | 3.2 | Low expression |
| HeLa (cervical carcinoma) | 0.5 | Not detected |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1234A>G (p.I412V) | Missense | 0.01% (gnomAD) | Unknown; likely benign |
| c.789C>T (p.S263F) | Missense | 0.005% (gnomAD) | Potential impact on ligand binding |
| c.1001G>A (p.R334Q) | Missense | 0.002% (gnomAD) | Unknown; not reported in ClinVar |
Mutation functional classification
Loss of Function (LOF)
No confirmed loss-of-function mutations reported in SIGLEC5.
Gain of Function (GOF)
No confirmed gain-of-function mutations reported.
Dominant Negative (DN)
No evidence for dominant-negative effects.
View complete mutation data：
Gene Ontology (GO)
| • carbohydrate binding | • protein binding |
| • sialic acid binding | • cell surface receptor signaling pathway |
| • negative regulation of immune response | • innate immune response |
| • plasma membrane |
Pathways
• Immune System
• Innate Immune System
• Siglec signaling
• Cell adhesion molecules (CAMs)
Protein Summary
SIGLEC5 is a 551-amino acid type I membrane protein with an extracellular N-terminal V-set domain that binds sialic acid, followed by two C2-set domains. The cytoplasmic tail contains ITIM and ITIM-like motifs that recruit phosphatases (e.g., SHP-1/2) upon phosphorylation, leading to inhibition of cellular activation. It is expressed on neutrophils, monocytes, and some B cells, and can be cleaved from the surface to produce soluble forms. SIGLEC5 also recognizes sialic acids on pathogens, facilitating immune evasion.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SIGLEC5 Knockout HEK293 Cell Line | EDJ-KQ6359 | Human | 8778 | Details Get a Quote |
| SIGLEC5 Knockout HeLa Cell Line | EDJ-KQ55001 | Human | 8778 | Details Get a Quote |
| SIGLEC5 Knockout A-549 Cell Line | EDJ-KQ63486 | Human | 8778 | Details Get a Quote |
| SIGLEC5 Knockout HCT 116 Cell Line | EDJ-KQ71955 | Human | 8778 | Details Get a Quote |
