
Quantitation of reduced IL-33 levels in human serum: mitigating interference from endogenous binding partners
Author(s) -
Joshua Zylstra,
M. Partridge,
Giane Sumner
Publication year - 2021
Publication title -
bioanalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.566
H-Index - 58
eISSN - 1757-6199
pISSN - 1757-6180
DOI - 10.4155/bio-2021-0172
Subject(s) - endogeny , chemistry , interleukin 33 , pharmacology , chromatography , immunology , biochemistry , medicine , interleukin , cytokine
Aim: IL-33 is a potential therapeutic target but commercially available assays for the quantitation of systemic IL-33 have poor reliability. Results: In commercial IL-33 kits, interference from endogenous binding partners (e.g., soluble ST2) causes under-quantitation. Mitigating this required acid dissociation and addition of the detection reagent simultaneously with the capture step. This enabled detection of total, reduced (active) levels of IL-33 in human serum (LLOQ 6.25 pg/ml). Conclusion: Acid treatment of serum samples dissociates IL-33 from endogenous binding partners, increasing soluble ST2 tolerance to >1000 ng/ml. The modified method was specific for reduced endogenous IL-33. Analysis of over 300 samples from individuals with and without asthma and with different smoking status revealed no difference in serum IL-33.