Label-free Quantitative Proteomics

Label-free Proteome Analysis Technology

Label-free, is label-free quantitative technology, is a mass spectrometry analysis of protein enzymatic peptide fragments by liquid chromatography-mass spectrometry technology, which overcomes the shortcomings of traditional isotope labeling, that is, high sample concentration, and less pretreatment, more retention of original information of samples;the coverage of low-abundance peptides is higher; it is not limited by the labeling kit, and large-scale sample detection can be performed.

Research Process

Sample Requirements

Normal animal tissue ≥ 70mg
Normal plant tissue ≥ 300mg
Microorganisms ≥ 80 μL
Cells ≥ 30 μL
Pure protein≥30µg
Serum/Plasma ≥ 450µL
Urine ≥ 7.5ml
Saliva, tears ≥ 1 mL
CSF ≥ 450µL
Lymph fluid, synovial fluid, puncture fluid ≥ 4.5ml

FFPE paraffin-embedded sections (10 μm thick, 1.5×2 cm area)≥15
Exosomes ≥ 50μL

Analysis Result

Case Analysis

Cerebrospinal Fluid Macrophage bBiomarkers in Amyotrophic Lateral Sclerosis

Journal：Annals of Neurology Impact factor: 9.037 Published date: 2018 Published by: Department of Clinical Neuroscience, University of Oxford, UK

Research Background

The neurodegenerative disease, amyotrophic lateral sclerosis (ALS), is a heterogeneous clinical syndrome involving multiple molecular pathways.

Research Result

Three macrophage-derived chitinases showed increased abundance in ALS: chitotriosidase (CHIT1), chitinase-3-like protein 1 (CHI3L1), and chitinase-3-like protein 2 (CHI3L2).

Figure 1 Differential protein content and ROC curve

Figure 2 Correlation analysis of differential proteins and disease progression

Conclusion

Elevated CHI3L1 was common to ALS and PLS, whereas CHIT1 and CHI3L2 levels differed. Chitinase levels correlated with disease progression rate CHIT1, CHI3L1, and CHI3L2 levels correlated with phosphorylated neurofilament heavy chain. CHI3L1 levels, but not CHIT1 or CHI3L2, increased over time in those with low initial levels. High CHIT1 was associated with shortened survival.

Reference

Thompson A G ,Gray E ,Marie-Laëtitia Thézénas, et al. Cerebrospinal fluid macrophage biomarkers in amyotrophic lateral sclerosis[J]. Annals of Neurology, 2018, 83(2)