4. The idea – Why?
to treat not to treatOR
Hypothesis:
Proper diagnosis will
reduce antimicrobial
(mis)-use.
5. The idea – How?
Development of a test that discriminates
between bacterial and viral infections
How ?
Identify host responses typical
for bacterial versus viral infections
6. Background
Sligthly modified from: Mittal, R et al. 2014. Int J. Infectious Diseases 29: 259-267
Overlap between bacterial and viral pathways
8. Selection of candidate genes
Gene Name Definition
Definite Bacterial vs.
Definite Viral
log2 FC q-value
Upregulated in viral infections
IFI27 interferon alpha inducible protein 27 -4.32 4.78E-21
IFI44L Homo sapiens interferon-induced protein 44-like, mRNA. -3.79 1.36E-22
IFIT1 interferon induced protein with tetratricopeptide repeats 1 -3.49 2.90E-20
RSAD2 radical S-adenosyl methionine domain containing 2 -3.28 5.14E-19
IFIT3 interferon induced protein with tetratricopeptide repeats 3 -2.66 2.47E-16
OTOF otoferlin -2.53 1.73E-14
MxA MX dynamin like GTPase 1
Upregulated in bacterial infections
FAM89A family with sequence similarity 89 member A 1.21 2.97E-14
UPB1 beta-ureidopropionase 1 1.23 5.27E-13
PTPN20 protein tyrosine phosphatase non-receptor type 20 1.35 1.88E-11
TMEM119 transmembrane protein 119 1.35 1.76E-08
SLPI secretory leukocyte peptidase inhibitor 1.84 2.44E-12
S100P S100 calcium binding protein P 2.35 1.39E-16
PI3 peptidase inhibitor 3; elafin precursor 2.58 4.52E-10
CRP C-reactive protein
9. Primer design
• Orthologues for selected genes were identified in S.
scrofa by sequence homology.
• 6 reference genes were identified from Uddin et al.
(2011) and new primer pairs designed for them.
• Primers were designed using NCBI’s Primer-BLAST
tool and their specificity confirmed using BLASTN.
14. Testing on reference and clinical samples
Refgenes
Viral
Bacterial
2216/polyIC PMA/ionomycin
15. Testing on reference and clinical samples
Refgenes
Viral
Bacterial
Haemophilus day 0 Haemophilus day 4
Actinobacillus acute
16. Testing on reference and clinical samples
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
LF524 SH86 pig No 14 day 4 Actbac pig 25
Average viral vs bacterial
viral bacterial
17. Conclusion
Development of a test that discriminates
between bacterial and viral infections
- Is it possible?
18. Conclusion
Development of a test that discriminates
between bacterial and viral infections
- Is it possible?
- Yes it is!
19. Conclusion
Development of a test that discriminates
between bacterial and viral infections
- Is it possible?
- Yes it is!
20. Next steps
• Improve/ test further bacterial biomarkers
• Optimization of assays
• Test on more clinical/trial samples (viral and bacterial
infections
• Develop similar assays for other livestock (cattle and goats)
• Identify suitable technology for the final test
22. This presentation is licensed for use under the Creative Commons Attribution 4.0 International Licence.
better lives through livestock
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