Seroatlas · Human Serome Atlas

SERPIND1

Heparin cofactor 2

Also known as: D22S673, HC-II, HC2, HCF2, HEP2_HUMAN, HLS2

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
P05546
Gene
SERPIND1
Ensembl
ENSG00000099937
Chromosome
22
Canonical length
499 aa
Protein class
Candidate cardiovascular disease genes, Disease related genes, FDA approved drug targets, Human disease related genes, Plasma proteins, Predicted secreted proteins
Subcellular location
Vesicles
Secretome location
Secreted to blood

OverviewNCBI Gene

This gene belongs to the serpin gene superfamily. Serpins play roles in many processes including inflammation, blood clotting, and cancer metastasis. Members of this family have highly conserved secondary structures with a reactive center loop that interacts with the protease active site to inhibit protease activity. This gene encodes a plasma serine protease that functions as a thrombin and chymotrypsin inhibitor. The protein is activated by heparin, dermatan sulfate, and glycosaminoglycans. Allelic variations in this gene are associated with heparin cofactor II deficiency. [provided by RefSeq, Jul 2015]

Canonical amino-acid sequenceUniProt

499 residues, UniProt reviewed canonical sequence.

>P05546|SERPIND1
     1  MKHSLNALLI FLIITSAWGG SKGPLDQLEK GGETAQSADP QWEQLNNKNL SMPLLPADFH
    61  KENTVTNDWI PEGEEDDDYL DLEKIFSEDD DYIDIVDSLS VSPTDSDVSA GNILQLFHGK
   121  SRIQRLNILN AKFAFNLYRV LKDQVNTFDN IFIAPVGIST AMGMISLGLK GETHEQVHSI
   181  LHFKDFVNAS SKYEITTIHN LFRKLTHRLF RRNFGYTLRS VNDLYIQKQF PILLDFKTKV
   241  REYYFAEAQI ADFSDPAFIS KTNNHIMKLT KGLIKDALEN IDPATQMMIL NCIYFKGSWV
   301  NKFPVEMTHN HNFRLNEREV VKVSMMQTKG NFLAANDQEL DCDILQLEYV GGISMLIVVP
   361  HKMSGMKTLE AQLTPRVVER WQKSMTNRTR EVLLPKFKLE KNYNLVESLK LMGIRMLFDK
   421  NGNMAGISDQ RIAIDLFKHQ GTITVNEEGT QATTVTTVGF MPLSTQVRFT VDRPFLFLIY
   481  EHRTSCLLFM GRVANPSRS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SERPIND1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.3
Highest tissue expression
1,172 nTPM

Expression across tissuesHPA

Tissue

  • liver: 1,172 nTPM
  • choroid plexus: 260 nTPM
  • parathyroid gland: 9.5 nTPM
  • lung: 2.3 nTPM
  • basal ganglia: 2.2 nTPM
  • endometrium: 1.8 nTPM

Single-cell type

  • hepatocytes: 326 nCPM
  • epicardial cells: 55 nCPM
  • granulosa cells: 16 nCPM
  • retinal ganglion cells: 16 nCPM
  • choroid plexus epithelial cells: 13 nCPM
  • cardiomyocytes: 12 nCPM

Immune cell

  • naive B-cell: 0.5 nTPM
  • plasmacytoid DC: 0.5 nTPM
  • MAIT T-cell: 0.3 nTPM
  • NK-cell: 0.3 nTPM
  • gdT-cell: 0.2 nTPM
  • naive CD4 T-cell: 0.2 nTPM

Brain region

  • choroid plexus: 191 nTPM
  • cerebellum: 9 nTPM
  • hippocampal formation: 8.8 nTPM
  • basal ganglia: 7.2 nTPM
  • cerebral cortex: 6.7 nTPM
  • amygdala: 5.3 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SERPIND1.

Disease | AllUniProt

Conditions SERPIND1 is implicated in, by any mechanism.

  • Thrombophilia due to heparin cofactor 2 deficiency (THPH10) MIM:612356

Disease | GeneticClinVar

4 pathogenic / likely-pathogenic of 101 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.5
gnomAD pLI
0
gnomAD missense Z
-0.06
DepMap mean gene effect
-0.02
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SERPIND1 as an antibody target. Whether an autoantibody or antibody against SERPIND1 could matter depends on whether native SERPIND1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SERPIND1 is annotated as secreted, so native SERPIND1 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label SERPIND1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SERPIND1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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