Seroatlas · Human Serome Atlas

SFTPD

Pulmonary surfactant-associated protein D

Also known as: COLEC7, SFTP4, SFTPD_HUMAN, SP-D

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

Protein identityUniProt · HPA

UniProt accession
P35247
Gene
SFTPD
Ensembl
ENSG00000133661
Chromosome
10
Canonical length
375 aa
Protein class
Predicted secreted proteins
Secretome location
Secreted in other tissues
Quaternary structure
Homotrimer

OverviewNCBI Gene

The protein encoded by this gene is part of the innate immune response, protecting the lungs against inhaled microorganisms and chemicals. The encoded protein may also be involved in surfactant metabolism. [provided by RefSeq, Jul 2015]

Canonical amino-acid sequenceUniProt

375 residues, UniProt reviewed canonical sequence.

>P35247|SFTPD
     1  MLLFLLSALV LLTQPLGYLE AEMKTYSHRT MPSACTLVMC SSVESGLPGR DGRDGREGPR
    61  GEKGDPGLPG AAGQAGMPGQ AGPVGPKGDN GSVGEPGPKG DTGPSGPPGP PGVPGPAGRE
   121  GPLGKQGNIG PQGKPGPKGE AGPKGEVGAP GMQGSAGARG LAGPKGERGV PGERGVPGNT
   181  GAAGSAGAMG PQGSPGARGP PGLKGDKGIP GDKGAKGESG LPDVASLRQQ VEALQGQVQH
   241  LQAAFSQYKK VELFPNGQSV GEKIFKTAGF VKPFTEAQLL CTQAGGQLAS PRSAAENAAL
   301  QQLVVAKNEA AFLSMTDSKT EGKFTYPTGE SLVYSNWAPG EPNDDGGSED CVEIFTNGKW
   361  NDRACGEKRL VVCEF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SFTPD 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)
0.57
Highest tissue expression
479 nTPM

Expression across tissuesHPA

Tissue

  • lung: 479 nTPM
  • bone marrow: 19 nTPM
  • choroid plexus: 8.8 nTPM
  • thyroid gland: 5.4 nTPM
  • skin: 4.7 nTPM
  • basal ganglia: 4.2 nTPM

Single-cell type

  • alveolar cells type 2: 1,442 nCPM
  • transitional alveolar cells: 367 nCPM
  • alveolar cells type 1: 184 nCPM
  • cardiomyocytes: 167 nCPM
  • myonuclei: 65 nCPM
  • ependymal cells: 26 nCPM

Immune cell

  • non-classical monocyte: 37 nTPM
  • intermediate monocyte: 10 nTPM
  • myeloid DC: 1.9 nTPM
  • total PBMC: 0.9 nTPM
  • eosinophil: 0.6 nTPM
  • classical monocyte: 0.4 nTPM

Brain region

  • hypothalamus: 4.5 nTPM
  • basal ganglia: 4.2 nTPM
  • choroid plexus: 4.2 nTPM
  • cerebral cortex: 4.1 nTPM
  • thalamus: 3.6 nTPM
  • amygdala: 3.4 nTPM

ReferencesPubMed · IEDB

Publications for SFTPD from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

1 publication

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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)
0.98
gnomAD pLI
0
gnomAD missense Z
0.58
DepMap mean gene effect
-0.02
DepMap dependency class
none

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

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

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

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

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