Seroatlas · Human Serome Atlas

SERPINB4

Serpin B4

Also known as: LEUPIN, PI11, SCCA-2, SCCA1, SCCA2, SPB4_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P48594
Gene
SERPINB4
Ensembl
ENSG00000206073
Chromosome
18
Canonical length
390 aa
Protein class
Cancer-related genes, Plasma proteins, Predicted intracellular proteins
Subcellular location
Plasma membrane,Cytosol

OverviewNCBI Gene

The protein encoded by this gene is a member of the serpin family of serine protease inhibitors. The encoded protein is highly expressed in many tumor cells and can inactivate granzyme M, an enzyme that kills tumor cells. This protein, along with serpin B3, can be processed into smaller fragments that aggregate to form an autoantigen in psoriasis, probably by causing chronic inflammation. [provided by RefSeq, Jan 2017]

Canonical amino-acid sequenceUniProt

390 residues, UniProt reviewed canonical sequence.

>P48594|SERPINB4
     1  MNSLSEANTK FMFDLFQQFR KSKENNIFYS PISITSALGM VLLGAKDNTA QQISKVLHFD
    61  QVTENTTEKA ATYHVDRSGN VHHQFQKLLT EFNKSTDAYE LKIANKLFGE KTYQFLQEYL
   121  DAIKKFYQTS VESTDFANAP EESRKKINSW VESQTNEKIK NLFPDGTIGN DTTLVLVNAI
   181  YFKGQWENKF KKENTKEEKF WPNKNTYKSV QMMRQYNSFN FALLEDVQAK VLEIPYKGKD
   241  LSMIVLLPNE IDGLQKLEEK LTAEKLMEWT SLQNMRETCV DLHLPRFKME ESYDLKDTLR
   301  TMGMVNIFNG DADLSGMTWS HGLSVSKVLH KAFVEVTEEG VEAAAATAVV VVELSSPSTN
   361  EEFCCNHPFL FFIRQNKTNS ILFYGRFSSP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SERPINB4 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.24
Highest tissue expression
151 nTPM

Expression across tissuesHPA

Tissue

  • vagina: 151 nTPM
  • cervix: 149 nTPM
  • esophagus: 92 nTPM
  • salivary gland: 21 nTPM
  • urinary bladder: 20 nTPM
  • skin: 8.9 nTPM

Single-cell type

  • esophageal apical cells: 1,424 nCPM
  • esophageal suprabasal cells: 1,305 nCPM
  • respiratory secretory cells: 290 nCPM
  • respiratory basal cells: 250 nCPM
  • suprabasal keratinocytes: 145 nCPM
  • endometrial secretory cells: 113 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • thalamus: 0.1 nTPM
  • amygdala: 0 nTPM
  • basal ganglia: 0 nTPM
  • cerebellum: 0 nTPM
  • cerebral cortex: 0 nTPM
  • choroid plexus: 0 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SERPINB4.

Disease | ImmuneIEDB

Conditions an epitope on SERPINB4 was assayed in.

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)
1.88
gnomAD pLI
0
gnomAD missense Z
-1.87
DepMap mean gene effect
0.17
DepMap dependency class
none

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

InteractionsUniProt · HPA

Protein binding partners of SERPINB4 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 SERPINB4 as an antibody target. Whether an autoantibody or antibody against SERPINB4 could matter depends on whether native SERPINB4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SERPINB4 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Source-annotated serology context

The source annotations explicitly mention antibody, autoantibody, autoantigen, or autoimmune context. This is biological context, not study-specific reactivity.

  • This protein, along with serpin B3, can be processed into smaller fragments that aggregate to form an autoantigen in psoriasis, probably by causing chronic inflammation.

Canonical record: https://seroatlas.com/gene/SERPINB4. 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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