The online version of this article (doi:10.1186/1475-2875-11-314) contains supplementary material, which is available to authorized users.
The author(s) declare that they have no competing interests.
RW participated in study design, experimentation, data analysis and drafted the manuscript. GF participated in study design, GC-MS optimization, data analysis and critical revision of the manuscript. TD conceived the study, and participated in its design and coordination, and critical revision of the manuscript. All authors read and approved the final manuscript.
There remains a need for techniques that improve the sensitive detection of viable Plasmodium falciparum as part of diagnosis and therapeutic monitoring in clinical studies and usual-care management of malaria infections. A non-invasive breath test based on P. falciparum- associated specific volatile organic compounds (VOCs) could fill this gap and provide insights into parasite metabolism and pathogenicity. The aim of this study was to determine whether VOCs are present in the headspace above in vitro P. falciparum cultures.
A novel, custom-designed apparatus was developed to enable efficient headspace sampling of infected and non-infected cultures. Conditions were optimized to support cultures of high parasitaemia (>20%) to improve the potential detection of parasite-specific VOCs. A number of techniques for VOC analysis were investigated including solid phase micro-extraction using two different polarity fibres, and purge and trap/thermal desorption, each coupled to gas chromatography–mass spectrometry. Each experiment and analysis method was performed at least on two occasions. VOCs were identified by comparing their mass spectra against commercial mass spectral libraries.
No unique malarial-specific VOCs could be detected relative to those in the control red blood cell cultures. This could reflect sequestration of VOCs into cell membranes and/or culture media but solvent extractions of supernatants and cell lysates using hexane, dichloromethane and ethyl acetate also showed no obvious difference compared to control non-parasitized cultures.
Future in vivo studies analysing the breath of patients with severe malaria who are harbouring a parasite biomass that is significantly greater than achievable in vitro may yet reveal specific clinically-useful volatile chemical biomarkers.
Safeukui I, Correas JM, Brousse V, Hirt D, Deplaine G, Mule S, Lesurtel M, Goasguen N, Sauvanet A, Couvelard A, Kerneis S, Khun H, Vigan-Womas I, Ottone C, Molina TJ, Treluyer JM, Mercereau-Puijalon O, Milon G, David PH, Buffet PA: Retention of Plasmodium falciparum ring-infected erythrocytes in the slow, open microcirculation of the human spleen. Blood. 2008, 112: 2520-2528. 10.1182/blood-2008-03-146779. CrossRefPubMed
Phillips M, Greenberg J: Ion-trap detection of volatile organic compounds in alveolar breath. Clin Chem. 1992, 38: 60-65. PubMed
Gordon SM, Szidon JP, Krotoszynski BK, Gibbons RD, O'Neill HJ: Volatile organic compounds in exhaled air from patients with lung cancer. Clin Chem. 1985, 31: 1278-1282. PubMed
Phillips M, Cataneo RN, Condos R, Ring Erickson GA, Greenberg J, La Bombardi V, Munawar MI, Tietje O: Volatile biomarkers of pulmonary tuberculosis in the breath. Tuberculosis (Edinb). 2007, 87: 44-52. 10.1016/j.tube.2006.03.004. CrossRef
Anstey NM, Handojo T, Pain MC, Kenangalem E, Tjitra E, Price RN, Maguire GP: Lung injury in vivax malaria: pathophysiological evidence for pulmonary vascular sequestration and posttreatment alveolar-capillary inflammation. J Infect Dis. 2007, 195: 589-596. 10.1086/510756. PubMedCentralCrossRefPubMed
Trager W: Cultivation of parasites in vitro. Am J Trop Med Hyg. 1978, 27: 216-222. PubMed
Wong RP, Salman S, Ilett KF, Siba PM, Mueller I, Davis TM: Desbutyl-lumefantrine is a metabolite of lumefantrine with potent in vitro antimalarial activity that may influence artemether-lumefantrine treatment outcome. Antimicrob Agents Chemother. 2011, 55: 1194-1198. 10.1128/AAC.01312-10. PubMedCentralCrossRefPubMed
Radfar A, Mendez D, Moneriz C, Linares M, Marin-Garcia P, Puyet A, Diez A, Bautista JM: Synchronous culture of Plasmodium falciparum at high parasitemia levels. Nat Protoc. 2009, 4: 1899-1915. PubMed
Chambers ST, Bhandari S, Scott-Thomas A, Syhre M: Novel diagnostics: progress toward a breath test for invasive Aspergillus fumigatus. Med Mycol. 2010, 49 (Suppl 1): S54-S61. PubMed
Preti G, Thaler E, Hanson CW, Troy M, Eades J, Gelperin A: Volatile compounds characteristic of sinus-related bacteria and infected sinus mucus: analysis by solid-phase microextraction and gas chromatography–mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci. 2009, 877: 2011-2018. 10.1016/j.jchromb.2009.05.028. CrossRefPubMed
Roth B, Herkenrath P, Lehmann HJ, Ohles HD, Homig HJ, Benz-Bohm G, Kreuder J, Younossi-Hartenstein A: Di-(2-ethylhexyl)-phthalate as plasticizer in PVC respiratory tubing systems: indications of hazardous effects on pulmonary function in mechanically ventilated, preterm infants. Eur J Pediatr. 1988, 147: 41-46. 10.1007/BF00442609. CrossRefPubMed
Mirovsky P: Continuous culture of Plasmodium falciparum asexual stages in "normal" air atmosphere. Folia Parasitol (Praha). 1989, 36: 107-112.
- Investigation of volatile organic biomarkers derived from Plasmodium falciparum in vitro
Rina PM Wong
Gavin R Flematti
Timothy ME Davis
- BioMed Central
Neu im Fachgebiet Innere Medizin
Meistgelesene Bücher aus der Inneren Medizin
e.Med Kampagnen-Visual, Mail Icon II