Part of Thermo Fisher Scientific




Proline-rich acidic protein 1

See alternative names Epididymis tissue protein Li 178,
Uterine-specific proline-rich acidic protein

Uniprot Function Description

Lipid-binding protein which promotes lipid absorption by facilitating MTTP-mediated lipid transfer (mainly triglycerides and phospholipids) and MTTP-mediated apoB lipoprotein assembly and secretion (By similarity). Protects the gastrointestinal epithelium from irradiation-induced apoptosis (By similarity). May play an important role in maintaining normal growth homeostasis in epithelial cells (PubMed:14583459). Involved in p53/TP53-dependent cell survival after DNA damage (PubMed:23235459). May downregulate the expression of MAD1L1 and exert a suppressive role in mitotic spindle assembly checkpoint in hepatocellular carcinomas (PubMed:24374861).

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

Within run precision Coefficient of Variation (CV)
Between run precision Coefficient of Variation (CV)

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

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.

14121086420−2−4−6NPXControl SamplesDisease Samples