Seroatlas · Human Serome Atlas

SFTPA1

Pulmonary surfactant-associated protein A1

Also known as: COLEC4, SFTA1_HUMAN, SFTP1, SP-A, SP-A1

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

Protein identityUniProt · HPA

UniProt accession
Q8IWL2
Gene
SFTPA1
Ensembl
ENSG00000122852
Chromosome
10
Canonical length
248 aa
Protein class
Disease related genes, Human disease related genes, Predicted secreted proteins
Secretome location
Secreted in other tissues
Quaternary structure
Homotrimer

OverviewNCBI Gene

This gene encodes a lung surfactant protein that is a member of a subfamily of C-type lectins called collectins. The encoded protein binds specific carbohydrate moieties found on lipids and on the surface of microorganisms. This protein plays an essential role in surfactant homeostasis and in the defense against respiratory pathogens. Mutations in this gene are associated with idiopathic pulmonary fibrosis. Alternate splicing results in multiple transcript variants. [provided by RefSeq, May 2010]

Canonical amino-acid sequenceUniProt

248 residues, UniProt reviewed canonical sequence.

>Q8IWL2|SFTPA1
     1  MWLCPLALNL ILMAASGAVC EVKDVCVGSP GIPGTPGSHG LPGRDGRDGL KGDPGPPGPM
    61  GPPGEMPCPP GNDGLPGAPG IPGECGEKGE PGERGPPGLP AHLDEELQAT LHDFRHQILQ
   121  TRGALSLQGS IMTVGEKVFS SNGQSITFDA IQEACARAGG RIAVPRNPEE NEAIASFVKK
   181  YNTYAYVGLT EGPSPGDFRY SDGTPVNYTN WYRGEPAGRG KEQCVEMYTD GQWNDRNCLY
   241  SRLTICEF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SFTPA1 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)
0.48
Highest tissue expression
6,680 nTPM

Expression across tissuesHPA

Tissue

  • lung: 6,680 nTPM
  • adrenal gland: 6.3 nTPM
  • ovary: 5.6 nTPM
  • spleen: 4.6 nTPM
  • seminal vesicle: 4.5 nTPM
  • stomach: 3.6 nTPM

Single-cell type

  • alveolar cells type 2: 15,063 nCPM
  • transitional alveolar cells: 2,015 nCPM
  • alveolar cells type 1: 262 nCPM
  • respiratory ionocytes: 109 nCPM
  • submucosal glandular cells: 43 nCPM
  • respiratory secretory cells: 40 nCPM

Immune cell

  • plasmacytoid DC: 2.7 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • cerebellum: 2.3 nTPM
  • cerebral cortex: 2 nTPM
  • amygdala: 1.7 nTPM
  • hippocampal formation: 1.4 nTPM
  • basal ganglia: 1.3 nTPM
  • white matter: 1.3 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SFTPA1.

Disease | AllUniProt

Conditions SFTPA1 is implicated in, by any mechanism.

  • Interstitial lung disease 1 (ILD1) MIM:619611
  • Respiratory distress syndrome in premature infants (RDS) MIM:267450

Disease | GeneticClinVar

4 pathogenic / likely-pathogenic of 104 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Interstitial lung disease 1

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)
1.45
gnomAD pLI
0
gnomAD missense Z
-0.71
DepMap mean gene effect
-0.09
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

InteractionsUniProt · HPA

Protein binding partners of SFTPA1 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 SFTPA1 as an antibody target. Whether an autoantibody or antibody against SFTPA1 could matter depends on whether native SFTPA1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SFTPA1 is annotated as secreted, so native SFTPA1 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 SFTPA1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SFTPA1. 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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