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Updated: May 17, 2026
07:58
qKAT: Quantitative Semi-automated Typing of Killer-cell Immunoglobulin-like Receptor Genes
Published on: March 6, 2019
KIR2DL5: An Orphan Inhibitory Receptor Displaying Complex Patterns of Polymorphism and Expression
Elisa Cisneros1, Manuela Moraru, Natalia Gómez-Lozano
1Immunogenetics-HLA, Immunology Department, Hospital Universitario Puerta de Hierro Majadahonda, Spain.
Frontiers in Immunology
|October 13, 2012
Summary
The discovery of KIR2DL5 (CD158f) on NK and T cells reveals the last functional KIR. Its unique genetic and functional traits offer insights into immune regulation and KIR transcription.
Area of Science:
- Immunology
- Genetics
- Cell Biology
Background:
- KIR2DL5 (CD158f) is the final identified functional killer cell immunoglobulin-like receptor (KIR) in the human genome.
- It shares structural similarities with KIR2DL4 but exhibits functional characteristics akin to KIRs recognizing classical HLA class I molecules.
- KIR2DL5 expression is found on natural killer (NK) and T lymphocytes.
Purpose of the Study:
- To review the unique genetic, structural, and functional features of KIR2DL5.
- To explore the implications of KIR2DL5's complex genetics, including gene duplication and epigenetic regulation.
- To discuss the potential role of KIR2DL5 in immune responses, despite its ligand remaining undefined.
Main Methods:
- Utilized a newly developed anti-KIR2DL5 (CD158f) antibody for detection.
- Analyzed the genetic history, including gene duplication events and allelic diversification.
- Investigated epigenetic regulation, specifically DNA methylation, affecting KIR2DL5 transcription.
- Examined functional aspects, such as NK cell inhibition via SHP-2 phosphatase and clonal distribution.
Main Results:
- Confirmed KIR2DL5 expression on NK and T cells, identifying it as the last functional KIR.
- Demonstrated that surface-expressed KIR2DL5 inhibits NK cells through SHP-2 phosphatase.
- Highlighted the complex genetics of KIR2DL5, including duplications and epigenetically silenced alleles.
- Noted the absence of any described activating KIR2DL5 homologues across species.
Conclusions:
- KIR2DL5 possesses a unique combination of genetic, structural, and functional properties.
- Its epigenetic regulation provides a model for studying KIR transcription.
- Further research is needed to fully elucidate KIR2DL5's role in immunity and identify its ligand.
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