Validation of quantitative polymerase chain reaction assays for measuring cytokine expression in equine macrophages.
- Journal Article
- Research Support
- N.I.H.
- Extramural
- Research Support
- U.S. Gov't
- Non-P.H.S.
- Validation Study
Summary
This research focused on validating a set of quantitative real-time polymerase chain reaction (QPCR) tests for measuring equine cytokine expression, which is a crucial part of studying horse immune system and inflammatory responses.
Explanation of the Research
The research focused on developing and validating a set of quantitative real-time polymerase chain reaction (QPCR) tests that can measure the expression of cytokines in the immune cells of horses. This can generate crucial insights into the pathogenesis of various diseases in horses.
- The tests were validated using QPCR primers and probes synthesized for the cytokine genes IL-1alpha, IL-1beta, IL-6, IL-8, and TNF-alpha, along with the 18S gene.
- To determine the amplification efficiency and variation within and between the tests, the researchers used 10-fold dilutions of plasmid corresponding to each gene. The amplification efficiencies for the probes and primers used ranged from 99% to 101%, indicating high efficiency.
- The mean coefficient of variation (CV) across the trials for both within and between variations was 0.63%, indicating high reliability of the tests.
Evidence of Specificity and Efficiency
The researchers presented evidence of the tests’ efficiency and specificity.
- Amplification efficiency was also determined using 2-fold dilutions of cDNA with results that ranged from 83% to 95%.
- To confirm the specificity of amplification, the researchers sequenced the DNA products of the reactions. This allowed them to verify that the reactions were targeting the correct genes.
Practical Application
The QPCR tests were also applied in practice on cDNA from equine monocyte derived macrophages (EMDM) stimulated with lipopolysaccharide (LPS).
- Three sets of EMDM were examined, with IL-1alpha showing the greatest amplification and IL-6 showing the least. The range of cytokine induction was greater than previously reported, ranging from 12-fold to 30,000-fold.
- This demonstrated that the developed QPCR tests were not only efficient and specific, but also applicable in practice for measuring cytokine expression in equine immune cells.
Conclusion
In conclusion, a new set of QPCR primers and probes suitable for quantifying the expression of equine cytokines was presented. The set had been rigorously tested, and the research demonstrated that it specifically targets the intended genes, presents high amplification efficiency, and is highly reproducible.
Cite This Article
Publication
Researcher Affiliations
- Department of Veterinary Pathobiology, Texas A&M University, MS 4467, College Station, TX 77843-4467, USA.
MeSH Terms
- Animals
- Cytokines / analysis
- Cytokines / biosynthesis
- DNA Primers / genetics
- Gene Expression
- Gene Expression Profiling / methods
- Gene Expression Profiling / veterinary
- Horses
- Macrophages / immunology
- RNA, Messenger / analysis
- Reproducibility of Results
- Reverse Transcriptase Polymerase Chain Reaction / methods
- Reverse Transcriptase Polymerase Chain Reaction / veterinary
Grant Funding
- R01 CA059278 / NCI NIH HHS
- R01 CA059278-11 / NCI NIH HHS
- CA059278 / NCI NIH HHS
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Citations
This article has been cited 2 times.- Ownby SL, Fortuno LV, Au AY, Grzanna MW, Rashmir-Raven AM, Frondoza CG. Expression of pro-inflammatory mediators is inhibited by an avocado/soybean unsaponifiables and epigallocatechin gallate combination.. J Inflamm (Lond) 2014 Mar 28;11(1):8.
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