XI International Meeting on Paracoccidioidomycosis

XI International Meeting on Paracoccidioidomycosis

Resume:16-3

Poster (Painel)

16-3

LIPIDOMIC ANALYSIS OF EXTRACELLULAR VESICLES FROM PARACOCCIDIOIDES BRASILIENSIS: COMPARISON BETWEEN Pb18 AND Pb3

Authors:

Milene Vallejo (UNIFESP - UNIVERSIDADE FEDERAL DE SAO PAULO) ; Ernesto Nakayasu (UTEP - UNIVERSITY OF TEXAS AT EL PASO) ; Luciane Ganiko (UTEP - UNIVERSITY OF TEXAS AT EL PASO) ; Felipe Lopes (UTEP - UNIVERSITY OF TEXAS AT EL PASO) ; Alisson Matsuo (UNIFESP - UNIVERSIDADE FEDERAL DE SAO PAULO) ; Larissa Longo (UNIFESP - UNIVERSIDADE FEDERAL DE SAO PAULO) ; Igor Almeida (UTEP - UNIVERSITY OF TEXAS AT EL PASO) ; Rosana Puccia (UNIFESP - UNIVERSIDADE FEDERAL DE SAO PAULO)

Abstract

Pb18 represents the major paraphyletic group S1 of the Paracoccidioides complex and has been widely used by researchers due to its virulence; Pb3 represents a cryptic PS2 species. These P. brasiliensis isolates evoke opposite types of disease progression in a B.10A mouse model. In the present work we showed that extracellular vesicles from Pb3 and Pb18 isolates were both able to stimulate cytokine production in RAW264.7 macrophages. However, tumor necrosis factor-α (TNF-α) production was higher when cells were stimulated with vesicles isolated from Pb3. Interestingly, a distinct phenomenon was observed for interleukin-10 expression, being the production of this cytokine higher when macrophages were stimulated with Pb18 vesicles. These results suggested that P. brasiliensis vesicles carry immunomodulatory components that might differentially interfere with the host-fungal relationship. We presently focused on finding differences between Pb3 and Pb18 extracellular vesicle lipidomes. Vesicle lipids were extracted with chloroform:methanol, chloroform:methanol:water, and fractionated in silica-gel 60. Phospholipids and glycolipids were analyzed by ESI-LIT-MS/MS, while sterols and fatty acid were analyzed by GC-MS/MS. We found phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA), phosphatidylinositol (PI), phosphatidylserine (PS), and phosphatidylglycerol (PG) with distinct fatty acid chains. In Pb18 vesicles, two different species of PI, namely alkyl-C16:0-acyl-C18:1 and alkyl-C16:0-acyl-C18:2, which were absent in Pb3, were detected. Fatty acid analysis showed that the predominant fatty acid in Pb3 vesicles was oleic acid (C18:1) followed by linoleic acid (C18:2), which was the most abundant in Pb18 vesicles. The prevalent sterol in Pb3 and Pb18 vesicles was ergosta-7,22-dien-3βol. The ratio of ergosta-7,22-dien-3βol:ergosterol in Pb3 vesicles was 8, while in Pb18 vesicles it was 1.13. The predominant species of neutral glycosphingolipids in both isolates was a glycosylceramide, Hex-h18:0/d19:2-Cer. Our lipidomics data will hopefully help identify immunomodulatory components differentially expressed among P. brasiliensis isolates and which might be responsible for their distinct interactions with the host. Support: FAPESP, CNPq, NIH (grants # 5G12RR008124-16A1 and 5G12RR008124-16A1S1)

Keyword: PARACOCCIDIOIDES BRASILIENSIS, LIPIDOMIC, EXTRACELLULAR VESICLES

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