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Journal of fungi (Basel, Switzerland)2021; 7(6); 474; doi: 10.3390/jof7060474

Immunological Cross-Reactivity of Proteins Extracted from the Oomycete Pythium insidiosum and the Fungus Basidiobolus ranarum Compromises the Detection Specificity of Immunodiagnostic Assays for Pythiosis.

Abstract: Pythiosis, a life-threatening disease caused by , has been increasingly diagnosed worldwide. A recently developed immunochromatographic test (ICT) enables the rapid diagnosis of pythiosis. During the 3-year clinical implementation of ICT in Thailand, we collected the laboratory reports of 38 animals with suspected pythiosis and detected ICT false-positive results in three horses and a dog with basidiobolomycosis. and cause infections with indistinguishable clinical and microscopic features. This study investigated cross-reactive antibodies by probing and crude extracts and cell-free synthesized I06 protein (encoded in genome, not other fungi) against a panel of pythiosis, basidiobolomycosis, rabbit anti-I06 peptide, and control sera by Western blot analyses. ICT false-positive results occurred from the cross-reactivity of anti- antibodies to the 15, 50, 60, and 120 kDa proteins of , not double infections caused by both pathogens. Notably, ICT could help to screen pythiosis, and the positive test requires confirmation by culture or molecular method. The detection specificity of ICT requires improvement. The crude extract containing multispecies antigens needs replacement with a refined -specific protein. We proposed that the 55 kDa I06 protein is an excellent candidate for developing a more specific serodiagnostic test for pythiosis.
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Publication Date: 2021-06-11 PubMed ID: 34208304PubMed Central: PMC8231275DOI: 10.3390/jof7060474Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research investigates the misdiagnosis of pythiosis, a severe disease in animals caused by Pythium insidiosum, due to the cross-reactivity of disease proteins with Basidiobolus ranarum, a different infectious agent. The study proposes that using a refined, species-specific protein may improve the accuracy of detection tests for pythiosis.

Research Background and Motivation

  • Pythiosis is an acute, life-threatening disease caused by the oomycete Pythium insidiosum, with increasing cases being reported globally.
  • Currently, a rapid diagnostic tool known as immunochromatographic test (ICT) is utilized to diagnose pythiosis. However, during ICT’s application in Thailand over a span of 3 years, researchers noticed some false-positive results in animals suspected of having pythiosis but actually suffering from Basidiobolomycosis, an entirely different disease caused by the fungus Basidiobolus ranarum.
  • The researchers realized that these misdiagnoses occurred due to the similarity in clinical and microscopic characteristics between diseases caused by Pythium insidiosum and Basidiobolus ranarum, leading to an urgent need to improve the specificity of the ICT diagnostic tool.

Investigation and Key Findings

  • The study essentially probes the cross-reactive antibodies in these distinct pathogens by analyzing the reactions between crude extracts and a specific protein, termed I06, found only in Pythium insidiosum, to various sera in laboratory settings.
  • The false-positive results in ICT were found to be resulting from a cross-reactive phenomenon. Here the anti-Pythium insidiosum antibodies cross-reacted with proteins of Basidiobolus ranarum, thus incorrectly indicating an infection with Pythium insidiosum.
  • Importantly, it was noted that these misdiagnosis events were not due to co-infections with both pathogens but solely due to the cross-reactive antibodies.

Implications and Proposed Solutions

  • Since the ICT diagnostic tool was prone to cross-reactive errors, researchers suggested improvements in test specificity to reduce false diagnosis rates.
  • The study proposed removing the crude extract employed in the test, which contained antigens from multiple species, and replacing it with a refined, Pythium insidiosum-specific protein.
  • The I06 protein, distinctive to Pythium insidiosum and not present in other fungi, was proposed as an excellent candidate protein for developing a more specific diagnostic test for pythiosis.

Conclusion

  • The research illuminates the importance of refining diagnostic materials to increase specificity and reduce false-positives, contributing to better health outcomes for animals suspected of pythiosis.

Cite This Article

APA
Rotchanapreeda T, Sae-Chew P, Lohnoo T, Yingyong W, Rujirawat T, Kumsang Y, Payattikul P, Jaturapaktrarak C, Intaramat A, Pathomsakulwong W, Yurayart C, Krajaejun T. (2021). Immunological Cross-Reactivity of Proteins Extracted from the Oomycete Pythium insidiosum and the Fungus Basidiobolus ranarum Compromises the Detection Specificity of Immunodiagnostic Assays for Pythiosis. J Fungi (Basel), 7(6), 474. https://doi.org/10.3390/jof7060474

Publication

Journal of fungi (Basel, Switzerland)
ISSN: 2309-608X
NlmUniqueID: 101671827
Country: Switzerland
Language: English
Volume: 7
Issue: 6
PII: 474

Researcher Affiliations

Rotchanapreeda, Tiwa
  • Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Sae-Chew, Pattarana
  • Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Lohnoo, Tassanee
  • Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Yingyong, Wanta
  • Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Rujirawat, Thidarat
  • Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Kumsang, Yothin
  • Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Payattikul, Penpan
  • Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Jaturapaktrarak, Chalisa
  • Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Intaramat, Akarin
  • Translational Research Unit and Laboratory of Immunology, Chulabhorn Research Institute, Bangkok 10210, Thailand.
Pathomsakulwong, Watcharapol
  • Equine Clinic, Kasetsart University Veterinary Teaching Hospital, Nakhon Pathom 73140, Thailand.
Yurayart, Chompoonek
  • Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand.
Krajaejun, Theerapong
  • Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.

Grant Funding

  • MU-PD_2020_7 / Mahidol University
  • RSA6280092 / Thailand Research Fund
  • CF_63008 / Mahidol University
  • (none) / Kasetsart University

Conflict of Interest Statement

The authors declare no conflict of interest.

References

This article includes 34 references
  1. Krajaejun T, Imkhieo S, Intaramat A, Ratanabanangkoon K. Development of an immunochromatographic test for rapid serodiagnosis of human pythiosis.. Clin Vaccine Immunol 2009 Apr;16(4):506-9.
    doi: 10.1128/CVI.00276-08pmc: PMC2668273pubmed: 19225072google scholar: lookup
  2. Intaramat A, Sornprachum T, Chantrathonkul B, Chaisuriya P, Lohnoo T, Yingyong W, Jongruja N, Kumsang Y, Sandee A, Chaiprasert A, Banyong R, Santurio JM, Grooters AM, Ratanabanangkoon K, Krajaejun T. Protein A/G-based immunochromatographic test for serodiagnosis of pythiosis in human and animal subjects from Asia and Americas.. Med Mycol 2016 Aug 1;54(6):641-7.
    doi: 10.1093/mmy/myw018pubmed: 27118800google scholar: lookup
  3. Jaturapaktrarak C, Payattikul P, Lohnoo T, Kumsang Y, Laikul A, Pathomsakulwong W, Yurayart C, Tonpitak W, Krajaejun T. Protein A/G-based enzyme-linked immunosorbent assay for detection of anti-Pythium insidiosum antibodies in human and animal subjects.. BMC Res Notes 2020 Mar 6;13(1):135.
    doi: 10.1186/s13104-020-04981-ypmc: PMC7059324pubmed: 32143691google scholar: lookup
  4. Chareonsirisuthigul T, Khositnithikul R, Intaramat A, Inkomlue R, Sriwanichrak K, Piromsontikorn S, Kitiwanwanich S, Lowhnoo T, Yingyong W, Chaiprasert A, Banyong R, Ratanabanangkoon K, Brandhorst TT, Krajaejun T. Performance comparison of immunodiffusion, enzyme-linked immunosorbent assay, immunochromatography and hemagglutination for serodiagnosis of human pythiosis.. Diagn Microbiol Infect Dis 2013 May;76(1):42-5.
    doi: 10.1016/j.diagmicrobio.2013.02.025pubmed: 23537786google scholar: lookup
  5. Jindayok T, Piromsontikorn S, Srimuang S, Khupulsup K, Krajaejun T. Hemagglutination test for rapid serodiagnosis of human pythiosis.. Clin Vaccine Immunol 2009 Jul;16(7):1047-51.
    doi: 10.1128/CVI.00113-09pmc: PMC2708401pubmed: 19494087google scholar: lookup
  6. Krajaejun T, Kunakorn M, Niemhom S, Chongtrakool P, Pracharktam R. Development and evaluation of an in-house enzyme-linked immunosorbent assay for early diagnosis and monitoring of human pythiosis.. Clin Diagn Lab Immunol 2002 Mar;9(2):378-82.
    doi: 10.1128/CDLI.9.2.378-382.2002pmc: PMC119942pubmed: 11874882google scholar: lookup
  7. Pracharktam R, Changtrakool P, Sathapatayavongs B, Jayanetra P, Ajello L. Immunodiffusion test for diagnosis and monitoring of human pythiosis insidiosi.. J Clin Microbiol 1991 Nov;29(11):2661-2.
    doi: 10.1128/jcm.29.11.2661-2662.1991pmc: PMC270400pubmed: 1774283google scholar: lookup
  8. Supabandhu J, Vanittanakom P, Laohapensang K, Vanittanakom N. Application of immunoblot assay for rapid diagnosis of human pythiosis.. J Med Assoc Thai 2009 Aug;92(8):1063-71.
    pubmed: 19694332
  9. Chitasombat MN, Jongkhajornpong P, Lekhanont K, Krajaejun T. Recent update in diagnosis and treatment of human pythiosis.. PeerJ 2020;8:e8555.
    doi: 10.7717/peerj.8555pmc: PMC7036273pubmed: 32117626google scholar: lookup
  10. Gaastra W, Lipman LJ, De Cock AW, Exel TK, Pegge RB, Scheurwater J, Vilela R, Mendoza L. Pythium insidiosum: an overview.. Vet Microbiol 2010 Nov 20;146(1-2):1-16.
    doi: 10.1016/j.vetmic.2010.07.019pubmed: 20800978google scholar: lookup
  11. Krajaejun T, Sathapatayavongs B, Pracharktam R, Nitiyanant P, Leelachaikul P, Wanachiwanawin W, Chaiprasert A, Assanasen P, Saipetch M, Mootsikapun P, Chetchotisakd P, Lekhakula A, Mitarnun W, Kalnauwakul S, Supparatpinyo K, Chaiwarith R, Chiewchanvit S, Tananuvat N, Srisiri S, Suankratay C, Kulwichit W, Wongsaisuwan M, Somkaew S. Clinical and epidemiological analyses of human pythiosis in Thailand.. Clin Infect Dis 2006 Sep 1;43(5):569-76.
    doi: 10.1086/506353pubmed: 16886148google scholar: lookup
  12. Mendoza L., Ajello L., McGinnis M.R.. Infection Caused by the Oomycetous Pathogen Pythium Insidiosum. J. Mycol. Med. 1996;6:151–164.
  13. Krajaejun T, Kunakorn M, Pracharktam R, Chongtrakool P, Sathapatayavongs B, Chaiprasert A, Vanittanakom N, Chindamporn A, Mootsikapun P. Identification of a novel 74-kiloDalton immunodominant antigen of Pythium insidiosum recognized by sera from human patients with pythiosis.. J Clin Microbiol 2006 May;44(5):1674-80.
    doi: 10.1128/JCM.44.5.1674-1680.2006pmc: PMC1479217pubmed: 16672392google scholar: lookup
  14. Yolanda H, Krajaejun T. Review of methods and antimicrobial agents for susceptibility testing against Pythium insidiosum.. Heliyon 2020 Apr;6(4):e03737.
    doi: 10.1016/j.heliyon.2020.e03737pmc: PMC7160450pubmed: 32322727google scholar: lookup
  15. Lerksuthirat T, Sangcakul A, Lohnoo T, Yingyong W, Rujirawat T, Krajaejun T. Evolution of the Sterol Biosynthetic Pathway of Pythium insidiosum and Related Oomycetes Contributes to Antifungal Drug Resistance.. Antimicrob Agents Chemother 2017 Apr;61(4).
    doi: 10.1128/AAC.02352-16pmc: PMC5365696pubmed: 28115356google scholar: lookup
  16. Tonpitak W, Pathomsakulwong W, Sornklien C, Krajaejun T, Wutthiwithayaphong S. First confirmed case of nasal pythiosis in a horse in Thailand.. JMM Case Rep 2018 Jan;5(1):e005136.
    doi: 10.1099/jmmcr.0.005136pmc: PMC5857371pubmed: 29568533google scholar: lookup
  17. Rujirawat T, Sridapan T, Lohnoo T, Yingyong W, Kumsang Y, Sae-Chew P, Tonpitak W, Krajaejun T. Single nucleotide polymorphism-based multiplex PCR for identification and genotyping of the oomycete Pythium insidiosum from humans, animals and the environment.. Infect Genet Evol 2017 Oct;54:429-436.
    doi: 10.1016/j.meegid.2017.08.004pubmed: 28826756google scholar: lookup
  18. Keeratijarut A, Lohnoo T, Yingyong W, Rujirawat T, Srichunrusami C, Onpeaw P, Chongtrakool P, Brandhorst TT, Krajaejun T. Detection of the oomycete Pythium insidiosum by real-time PCR targeting the gene coding for exo-1,3-β-glucanase.. J Med Microbiol 2015 Sep;64(9):971-977.
    doi: 10.1099/jmm.0.000117pubmed: 26296566google scholar: lookup
  19. Keeratijarut A., Lohnoo T., Yingyong W., Nampoon U., Lerksuthirat T., Onpaew P., Chongtrakool P., Krajaejun T.. PCR Amplification of a Putative Gene for Exo-1, 3-Beta-Glucanase to Identify the Pathogenic Oomycete Pythium Insidiosum. Asian Biomed. 2014;8:637–644.
    doi: 10.5372/1905-7415.0805.338google scholar: lookup
  20. Htun ZM, Rotchanapreeda T, Rujirawat T, Lohnoo T, Yingyong W, Kumsang Y, Sae-Chew P, Payattikul P, Yurayart C, Limsivilai O, Sonthayanon P, Mangmee S, Chongtrakool P, Krajaejun T. Loop-mediated Isothermal Amplification (LAMP) for Identification of Pythium insidiosum.. Int J Infect Dis 2020 Dec;101:149-159.
    doi: 10.1016/j.ijid.2020.09.1430pubmed: 32987181google scholar: lookup
  21. Sae-Chew P, Rujirawat T, Kumsang Y, Payattikul P, Lohnoo T, Yingyong W, Jaturapaktrarak C, Rotchanapreeda T, Reamtong O, Srisuk T, Kittichotirat W, Krajaejun T. Automated Cell-Free Multiprotein Synthesis Facilitates the Identification of a Secretory, Oligopeptide Elicitor-Like, Immunoreactive Protein of the Oomycete Pythium insidiosum.. mSystems 2020 May 12;5(3).
    doi: 10.1128/mSystems.00196-20pmc: PMC7219551pubmed: 32398276google scholar: lookup
  22. Irinyi L, Lackner M, de Hoog GS, Meyer W. DNA barcoding of fungi causing infections in humans and animals.. Fungal Biol 2016 Feb;120(2):125-36.
    doi: 10.1016/j.funbio.2015.04.007pubmed: 26781368google scholar: lookup
  23. Mar Htun Z, Laikul A, Pathomsakulwong W, Yurayart C, Lohnoo T, Yingyong W, Kumsang Y, Payattikul P, Sae-Chew P, Rujirawat T, Jittorntam P, Jaturapaktrarak C, Chongtrakool P, Krajaejun T. Identification and Biotyping of Pythium insidiosum Isolated from Urban and Rural Areas of Thailand by Multiplex PCR, DNA Barcode, and Proteomic Analyses.. J Fungi (Basel) 2021 Mar 24;7(4).
    doi: 10.3390/jof7040242pmc: PMC8063814pubmed: 33804838google scholar: lookup
  24. Keeratijarut A, Karnsombut P, Aroonroch R, Srimuang S, Sangruchi T, Sansopha L, Mootsikapun P, Larbcharoensub N, Krajaejun T. Evaluation of an in-house immunoperoxidase staining assay for histodiagnosis of human pythiosis.. Southeast Asian J Trop Med Public Health 2009 Nov;40(6):1298-305.
    pubmed: 20578465
  25. White T., Bruns T., Lee S., Taylor J.. PCR Protocols: A Guide to Methods and Applications. Academic Press; Orlando, FL, USA: 1990. Amplification and Direct Sequencing of Fungal Ribosomal RNA Genes for Phylogenetics; pp. 315–322.
  26. Lohnoo T, Jongruja N, Rujirawat T, Yingyon W, Lerksuthirat T, Nampoon U, Kumsang Y, Onpaew P, Chongtrakool P, Keeratijarut A, Brandhorst TT, Krajaejun T. Efficiency comparison of three methods for extracting genomic DNA of the pathogenic oomycete Pythium insidiosum.. J Med Assoc Thai 2014 Mar;97(3):342-8.
    pubmed: 25123015
  27. Kamoun S. Molecular genetics of pathogenic oomycetes.. Eukaryot Cell 2003 Apr;2(2):191-9.
    doi: 10.1128/EC.2.2.191-199.2003pmc: PMC154851pubmed: 12684368google scholar: lookup
  28. Prabhu RM, Patel R. Mucormycosis and entomophthoramycosis: a review of the clinical manifestations, diagnosis and treatment.. Clin Microbiol Infect 2004 Mar;10 Suppl 1:31-47.
    doi: 10.1111/j.1470-9465.2004.00843.xpubmed: 14748801google scholar: lookup
  29. Shaikh N, Hussain KA, Petraitiene R, Schuetz AN, Walsh TJ. Entomophthoramycosis: a neglected tropical mycosis.. Clin Microbiol Infect 2016 Aug;22(8):688-94.
    doi: 10.1016/j.cmi.2016.04.005pubmed: 27109491google scholar: lookup
  30. Gugnani HC. Entomophthoromycosis due to Conidiobolus.. Eur J Epidemiol 1992 May;8(3):391-6.
    doi: 10.1007/BF00158574pubmed: 1397203google scholar: lookup
  31. Vilela R, Mendoza L. Human Pathogenic Entomophthorales.. Clin Microbiol Rev 2018 Oct;31(4).
    doi: 10.1128/CMR.00014-18pmc: PMC6148186pubmed: 30158298google scholar: lookup
  32. Rujirawat T, Patumcharoenpol P, Lohnoo T, Yingyong W, Lerksuthirat T, Tangphatsornruang S, Suriyaphol P, Grenville-Briggs LJ, Garg G, Kittichotirat W, Krajaejun T. Draft Genome Sequence of the Pathogenic Oomycete Pythium insidiosum Strain Pi-S, Isolated from a Patient with Pythiosis.. Genome Announc 2015 Jun 18;3(3).
    doi: 10.1128/genomeA.00574-15pmc: PMC4472884pubmed: 26089407google scholar: lookup
  33. Rujirawat T, Patumcharoenpol P, Lohnoo T, Yingyong W, Kumsang Y, Payattikul P, Tangphatsornruang S, Suriyaphol P, Reamtong O, Garg G, Kittichotirat W, Krajaejun T. Probing the Phylogenomics and Putative Pathogenicity Genes of Pythium insidiosum by Oomycete Genome Analyses.. Sci Rep 2018 Mar 7;8(1):4135.
    doi: 10.1038/s41598-018-22540-1pmc: PMC5841299pubmed: 29515152google scholar: lookup
  34. Rujirawat T, Patumcharoenpol P, Kittichotirat W, Krajaejun T. Oomycete Gene Table: an online database for comparative genomic analyses of the oomycete microorganisms.. Database (Oxford) 2019 Jan 1;2019.
    doi: 10.1093/database/baz082pmc: PMC6601393pubmed: 31260041google scholar: lookup

Citations

This article has been cited 4 times.
  1. Yolanda H, Krajaejun T. History and Perspective of Immunotherapy for Pythiosis. Vaccines (Basel) 2021 Sep 26;9(10).
    doi: 10.3390/vaccines9101080pubmed: 34696188google scholar: lookup
  2. Gurnani B, Kaur K. Immune Camouflage in Pythium insidiosum Keratitis: A Hypothesis on Molecular Mimicry and Host Pattern Recognition Receptor Evasion. Clin Ophthalmol 2025;19:4855-4873.
    doi: 10.2147/OPTH.S560311pubmed: 41446892google scholar: lookup
  3. Yurayart N, Jittorntam P, Kumsang Y, Rujirawat T, Jiaranaikulwanich A, Krajaejun T. Enhanced detection of Pythium insidiosum via lipid profiling with matrix-assisted laser desorption ionization time of flight mass spectrometry. IMA Fungus 2024 Nov 1;15(1):32.
    doi: 10.1186/s43008-024-00163-8pubmed: 39482776google scholar: lookup
  4. Luangnara A, Chuamanochan M, Chiewchanvit S, Pattamapaspong N, Salee P, Chaiwarith R. Pythiosis presenting with chronic swelling and painful subcutaneous lesion at right deltoid. IDCases 2023;33:e01873.
    doi: 10.1016/j.idcr.2023.e01873pubmed: 37637497google scholar: lookup
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