Seroatlas · Human Serome Atlas

A1BG

Alpha-1B-glycoprotein

Also known as: A1BG_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P04217
Gene
A1BG
Ensembl
ENSG00000121410
Chromosome
19
Canonical length
495 aa
Protein class
Plasma proteins, Predicted intracellular proteins, Predicted secreted proteins
Secretome location
Secreted to blood

OverviewNCBI Gene

The protein encoded by this gene is a plasma glycoprotein of unknown function. The protein shows sequence similarity to the variable regions of some immunoglobulin supergene family member proteins. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

495 residues, UniProt reviewed canonical sequence.

>P04217|A1BG
     1  MSMLVVFLLL WGVTWGPVTE AAIFYETQPS LWAESESLLK PLANVTLTCQ AHLETPDFQL
    61  FKNGVAQEPV HLDSPAIKHQ FLLTGDTQGR YRCRSGLSTG WTQLSKLLEL TGPKSLPAPW
   121  LSMAPVSWIT PGLKTTAVCR GVLRGVTFLL RREGDHEFLE VPEAQEDVEA TFPVHQPGNY
   181  SCSYRTDGEG ALSEPSATVT IEELAAPPPP VLMHHGESSQ VLHPGNKVTL TCVAPLSGVD
   241  FQLRRGEKEL LVPRSSTSPD RIFFHLNAVA LGDGGHYTCR YRLHDNQNGW SGDSAPVELI
   301  LSDETLPAPE FSPEPESGRA LRLRCLAPLE GARFALVRED RGGRRVHRFQ SPAGTEALFE
   361  LHNISVADSA NYSCVYVDLK PPFGGSAPSE RLELHVDGPP PRPQLRATWS GAVLAGRDAV
   421  LRCEGPIPDV TFELLREGET KAVKTVRTPG AAANLELIFV GPQHAGNYRC RYRSWVPHTF
   481  ESELSDPVEL LVAES

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against A1BG 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
565 nTPM

Expression across tissuesHPA

Tissue

  • liver: 565 nTPM
  • fallopian tube: 0.7 nTPM
  • cerebral cortex: 0.3 nTPM
  • lymph node: 0.3 nTPM
  • endometrium: 0.2 nTPM
  • heart muscle: 0.2 nTPM

Single-cell type

  • oligodendrocytes: 23 nCPM
  • ependymal cells: 17 nCPM
  • podocytes: 7.7 nCPM
  • brain excitatory neurons: 7.3 nCPM
  • other brain neurons: 5.5 nCPM
  • microglia: 4.9 nCPM

Immune cell

  • plasmacytoid DC: 0.2 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • choroid plexus: 1.1 nTPM
  • cerebellum: 0.9 nTPM
  • basal ganglia: 0.8 nTPM
  • midbrain: 0.8 nTPM
  • white matter: 0.8 nTPM
  • cerebral cortex: 0.7 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)
1.21
gnomAD pLI
0
gnomAD missense Z
-0.09
DepMap mean gene effect
-0.08
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of A1BG 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 A1BG as an antibody target. Whether an autoantibody or antibody against A1BG could matter depends on whether native A1BG is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

A1BG is annotated as secreted, so native A1BG 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 A1BG as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/A1BG. 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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