Back to discover

Protein / target

Natural killer cells antigen CD94

Encoded byKLRD1Q13241Homo sapiensSwiss-Prot
Antibody-tractable
Druggability
UniProt loc high conf
1
Research papers

Protein at a glance

Biological role

HLA-E specific inhibitory MHC class Ib receptor

Strongest disease association

Neoplasms

Via encoding gene KLRD1 · Literature evidence · score 0.10

Research activity

Emerging research

1 papers · latest 2025

Derived from structured UniProt, Open Targets and literature data on this page.

Protein profile

UniProt 2026_02

Canonical identity and biological annotation from UniProt.

Function overview

Immune receptor involved in self-nonself discrimination.

View complete UniProt function annotation

Immune receptor involved in self-nonself discrimination. In complex with KLRC1 or KLRC2 on cytotoxic and regulatory lymphocyte subsets, recognizes non-classical major histocompatibility (MHC) class Ib molecule HLA-E loaded with self-peptides derived from the signal sequence of classical MHC class Ia and non-classical MHC class Ib molecules (PubMed:10023772, PubMed:18064301, PubMed:18083576, PubMed:37264229, PubMed:9486650, PubMed:9754572). Enables cytotoxic cells to monitor the expression of MHC class I molecules in healthy cells and to tolerate self (PubMed:12387742, PubMed:18064301, PubMed:9430220). Primarily functions as a ligand binding subunit as it lacks the capacity to signal

Subcellular location

Cell membrane
Domains and Gene Ontology detail (20)

Domains & features

C-type lectin

Gene Ontology

  • Ccell surface
  • Cexternal side of plasma membrane
  • Cplasma membrane
  • Creceptor complex
  • Fcarbohydrate binding
  • FHLA-A specific activating MHC class I receptor activity
  • FHLA-E specific inhibitory MHC class Ib receptor activity
  • FMHC class I protein complex binding
  • FMHC class Ib protein binding, via antigen binding groove
  • Fprotein antigen binding
  • Ftransmembrane signaling receptor activity
  • Padaptive immune response

179 aa · 21 kDa · 3 isoforms

Biological roles

What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.

Immune signallingGO
View supporting evidence

Immune signalling

  • ·MHC class Ib protein binding, via antigen binding groove
  • ·protein antigen binding
  • ·adaptive immune response
  • ·negative regulation of T cell mediated cytotoxicity

Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.

Translational evidence

Open Targets 26

Why this target matters therapeutically, strongest evidence first. Disease associations are gene-level (via the gene that encodes this protein) and open into the full confidence synthesis; the development universe, tractability and safety annotations are target-level, from Open Targets.

Strongest disease associations · via encoding gene KLRD1

Gene-level evidence surfaced through the gene KLRD1 that encodes this protein — not a direct protein–disease relationship. Ranked by Forefront's causal-directness weighting, so genetically- and clinically-evidenced diseases lead over ones that merely share the literature.

Neoplasms
0.12Preliminary

Literature evidence dominant · Open Targets 0.10 · no direct causal or clinical evidence

Celiac Disease
0.10Preliminary

Literature evidence dominant · Open Targets 0.08 · no direct causal or clinical evidence

Graft vs Host Disease
0.09Preliminary

Literature evidence dominant · Open Targets 0.07 · no direct causal or clinical evidence

Lupus Erythematosus, Systemic
0.07Preliminary

Literature evidence dominant · Open Targets 0.06 · no direct causal or clinical evidence

Precursor Cell Lymphoblastic Leukemia-Lymphoma
0.07Preliminary

Literature evidence dominant · Open Targets 0.06 · no direct causal or clinical evidence

View evidence synthesis (5)
NeoplasmsPreliminary
0.12
agreement 0.000.39
Literature100%

Open Targets aggregate 0.10 · 1 independent evidence family · no direct causal or clinical evidence

Celiac DiseasePreliminary
0.10
agreement 0.000.37
Literature100%

Open Targets aggregate 0.08 · 1 independent evidence family · no direct causal or clinical evidence

Graft vs Host DiseasePreliminary
0.09
agreement 0.000.36
Literature100%

Open Targets aggregate 0.07 · 1 independent evidence family · no direct causal or clinical evidence

Lupus Erythematosus, SystemicPreliminary
0.07
agreement 0.000.35
Literature100%

Open Targets aggregate 0.06 · 1 independent evidence family · no direct causal or clinical evidence

Precursor Cell Lymphoblastic Leukemia-LymphomaPreliminary
0.07
agreement 0.000.34
Literature100%

Open Targets aggregate 0.06 · 1 independent evidence family · no direct causal or clinical evidence

The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the per-type scores above show the calculation.

Show all associations
Neoplasms0.10
Celiac Disease0.08
Graft vs Host Disease0.07
Lupus Erythematosus, Systemic0.06
Precursor Cell Lymphoblastic Leukemia-Lymphoma0.06
Influenza, Human0.05
Pulmonary Disease, Chronic Obstructive0.05
Central Nervous System Neoplasms0.05
Glioma0.05

Tractability

AntibodiesEmerging

Feasibility evidence (uniprot loc high conf and go cc high conf) — no clinical-stage drug of this modality recorded.

View underlying tractability evidence (3)
AB · UniProt loc high confAB · GO CC high confAB · UniProt SigP or TMHMM

Raw Open Targets tractability assessment buckets, by modality.

Research activity

1 papers · to 2025

Papers linked directly to this protein. This is the protein's own literature — descriptor-derived papers are kept separate below.

Most cited

Gillespie GM · Immunological reviews · 2025

Recent

Europe PMC papers linked directly to this protein.