Seroatlas · Human Serome Atlas

SPINT1

Kunitz-type protease inhibitor 1

Also known as: HAI, HAI-1, MANSC2, SPIT1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
O43278
Gene
SPINT1
Ensembl
ENSG00000166145
Chromosome
15
Canonical length
529 aa
Protein class
Cancer-related genes, Plasma proteins, Predicted intracellular proteins, Predicted membrane proteins, Predicted secreted proteins, Transporters
Subcellular location
Nucleoplasm,Plasma membrane,Cytosol
Secretome location
Secreted to blood

OverviewNCBI Gene

The protein encoded by this gene is a member of the Kunitz family of serine protease inhibitors. The protein is a potent inhibitor specific for HGF activator and is thought to be involved in the regulation of the proteolytic activation of HGF in injured tissues. Alternative splicing results in multiple variants encoding different isoforms. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

529 residues, UniProt reviewed canonical sequence.

>O43278|SPINT1
     1  MAPARTMARA RLAPAGIPAV ALWLLCTLGL QGTQAGPPPA PPGLPAGADC LNSFTAGVPG
    61  FVLDTNASVS NGATFLESPT VRRGWDCVRA CCTTQNCNLA LVELQPDRGE DAIAACFLIN
   121  CLYEQNFVCK FAPREGFINY LTREVYRSYR QLRTQGFGGS GIPKAWAGID LKVQPQEPLV
   181  LKDVENTDWR LLRGDTDVRV ERKDPNQVEL WGLKEGTYLF QLTVTSSDHP EDTANVTVTV
   241  LSTKQTEDYC LASNKVGRCR GSFPRWYYDP TEQICKSFVY GGCLGNKNNY LREEECILAC
   301  RGVQGGPLRG SSGAQATFPQ GPSMERRHPV CSGTCQPTQF RCSNGCCIDS FLECDDTPNC
   361  PDASDEAACE KYTSGFDELQ RIHFPSDKGH CVDLPDTGLC KESIPRWYYN PFSEHCARFT
   421  YGGCYGNKNN FEEEQQCLES CRGISKKDVF GLRREIPIPS TGSVEMAVAV FLVICIVVVV
   481  AILGYCFFKN QRKDFHGHHH HPPPTPASST VSTTEDTEHL VYNHTTRPL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SPINT1 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
Cell surface
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.37
Highest tissue expression
223 nTPM

Expression across tissuesHPA

Tissue

  • esophagus: 223 nTPM
  • duodenum: 144 nTPM
  • salivary gland: 143 nTPM
  • placenta: 127 nTPM
  • small intestine: 126 nTPM
  • skin: 124 nTPM

Single-cell type

  • esophageal apical cells: 2,822 nCPM
  • syncytiotrophoblasts: 2,063 nCPM
  • cytotrophoblasts: 1,471 nCPM
  • migrating cytotrophoblasts: 978 nCPM
  • enterocytes: 488 nCPM
  • colonocytes: 382 nCPM

Immune cell

  • myeloid DC: 32 nTPM
  • neutrophil: 25 nTPM
  • classical monocyte: 19 nTPM
  • non-classical monocyte: 18 nTPM
  • intermediate monocyte: 16 nTPM
  • eosinophil: 14 nTPM

Brain region

  • choroid plexus: 12 nTPM
  • cerebellum: 9.9 nTPM
  • midbrain: 6.7 nTPM
  • hypothalamus: 6.3 nTPM
  • medulla oblongata: 5.6 nTPM
  • thalamus: 5.6 nTPM

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)
0.82
gnomAD pLI
0
gnomAD missense Z
0.07
DepMap mean gene effect
-0.29
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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

InteractionsUniProt · HPA

Protein binding partners of SPINT1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SPINT1 as an antibody target. Whether an autoantibody or antibody against SPINT1 could matter depends on whether native SPINT1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SPINT1 is annotated at the cell surface, where native SPINT1 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label SPINT1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SPINT1. 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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