Olink

Olink®
Part of Thermo Fisher Scientific

ONCOLOGY

Gene
SFTPA1

Uniprot
Q8IWL2

Protein
Pulmonary surfactant-associated protein A1

See alternative names Collectin-4,
Alveolar proteinosis protein,
35 kDa pulmonary surfactant-associated protein

Uniprot Function Description

(Microbial infection) Recognition of M.tuberculosis by dendritic cells may occur partially via this molecule (PubMed:17158455, PubMed:21203928). Can recognize, bind, and opsonize pathogens to enhance their elimination by alveolar macrophages (PubMed:21123169).

In presence of calcium ions, it binds to surfactant phospholipids and contributes to lower the surface tension at the air-liquid interface in the alveoli of the mammalian lung and is essential for normal respiration. Enhances the expression of MYO18A/SP-R210 on alveolar macrophages (By similarity).

Sample type

Human EDTA plasma and serum are the recommended sample types. Human citrate plasma and heparin plasma are also accepted. For other samples types e.g cerebrospinal fluid, (CSF), tissue or cell lysates please we recommend Olink Target 96 panels. Please note that protein expression levels are expected to vary in different sample types and certain assays may be affected by interfering substances such as hemolysate.

Precision

Precision (repeatability) is calculated from linearized NPX values over LOD.

Within run precision Coefficient of Variation (CV)
10%
Between run precision Coefficient of Variation (CV)
29%

Analytical measuring range

The technical data reported below refers to the measured value in the in vitro validation assays run using known concentrations of recombinant antigen. Please note that these figures are for reference only and CANNOT be used to convert NPX values to absolute concentrations for proteins measured in plasma or serum samples.

LOD (pg/mL)
3125
LLOQ (pg/mL)
3125
ULOQ (pg/mL)
100000
Hook (pg/mL)
400000
Range (logs)
1.5

Dilution factor

For optimal assay readout, Olink Explore is run using different dilutions of the original samples (undiluted, 1:10, 1:100 or 1:1000). The dilution factor for this assay is noted below and should be taken into account when estimating the appropriate addressable biological concentration of the protein based on the in vitro validation data.

Dilution factor
1:1

Sensitivity plot

The calibrator curve shown below visualizes the analytical measuring range data based on in vitro measurement of recombinant antigen. Please note that this is shown for reference only and CANNOT be used to convert NPX values to absolute concentrations for proteins measured in plasma or serum samples. The vertical dotted lines represent LLOQ and ULOQ respectively, and the horizontal line indicates the LOD.

10⁻⁴10⁻³10⁻²10⁻¹10⁰10¹10²10³10⁴10⁵10⁶10⁷181614121086420−2pg/mLNPXReplicate4PLLODLLOQULOQ

Sample distribution plot

The plot below shows the levels of protein measured in a number of commercial plasma samples. Healthy subjects are shown in blue and samples obtained from patients with a range of diseases are shown in red. The latter include inflammatory, cardiovascular, autoimmune & neurological diseases, as well as cancer. The data is shown to give a general idea of the sort of data range to expect, but cannot cover all potential levels that may be seen in clinical samples.

181614121086420−2NPXControl SamplesDisease Samples

Biomarker Validation Data

Additional validation data, as well as a more detailed description of how the Olink panels are quality controlled can be found in our Data Validation documents – go to Document download center

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