Neutrophil Extracellular Traps Formation: Effect of Leishmania major promastigotes and salivary gland homogenates of Phlebotomus papatasi in human neutrophil culture

• DOI: 10.21203/rs.3.rs-3804428/v1
• Publication Date: 2024-01-03T18:08:52Z
• Authors: Fahimeh Firouzjaie; Niloofar Taghipour; Amir Ahmad Akhavan; Seyyed Javad Seyy...; Soheila Rouhani; Maryam Shirazian; Ameneh Koochaki; Mahboubeh Fatemi; Nariman Mossafa; Vahideh Moin Vaziri
• Keywords: Neutrophil Extracellular Traps; Acridine orange; Azurophilic granule; Ethidium bromide; Giemsa stain

Abstract Background Leishmaniasis as a neglected tropical disease (NTD) is caused by the inoculation of Leishmania parasites via bite phlebotomine sand flies. After an infected bite, series innate and adaptive immune responses occurs, among which neutrophils can be mentioned initiators. Among multiple functions these fighting cells, neutrophil extracellular traps (NETs) were studied in presence major promastigotes salivary gland homogenates (SGH) Phlebotomus papatasi alone, combination to mimic natural conditions transmission. Material & Methods The effect L. SGH on NETs formation was three different groups: + (NS), (NL), (NLS) along with negative positive controls 2, 4 6 hours post-incubation. Different microscopic methods used visualize comprising: fluorescence microscopy Acridine Orange/ Ethidium Bromide staining, optical Giemsa staining scanning electron microscopy. In addition, expression level genes NE, MPO MMP9 evaluated Real-Time PCR. Results All microscopical revealed similar results, NS group, chromatin extrusion sign NETosis, not very evident each time points; but, NL especially NLS more NETosis observed interaction between also saliva gradually increased over times. Real-time reveals that, MPO, NE during 2 after exposure, then decreased at most groups. Conclusion Hence, it determined that simultaneous parasite group has greater impact compared