Superparamagnetic iron oxide nanoparticles (SPIONs) are recognized as one of the most beneficial tools for biomedicine, especially in theranostic applications. Even though SPIONs have excellent properties regarding their biocompatibility and unique magnetic properties, they lack stability in biological fluids. To stabilize and increase the specificity of the SPIONs to target desirable cells or tissues, several surface coatings have been introduced. These surface coatings can lead to different preferences of serum protein bindings, which ultimately determine their behaviors in vitro and in vivo. Thus, understanding the interaction of SPIONs with biological systems is important for their biocompatible design and clinical applications. In this study, using proteomic analyses, we analyzed the protein corona fingerprints on SPIONs with two different coatings, including citrate and riboflavin, that have been widely used as surface coatings and ligands for enhancing cellular uptake in breast cancer cells. Though both citrate-coated SPIONs (C-SPIONs) and riboflavin-coated SPIONs (Rf-SPIONs) showed similar sizes and zeta potentials, we found that Rf-SPIONs adsorbed more serum proteins than bare SPIONs (B-SPIONs) or C-SPIONs, which was likely due to the higher hydrophobicity of the riboflavin. The enriched proteins consisted mainly of immune-responsive and blood coagulation proteins with different fingerprint profiles. Cellular uptake studies in MCF-7 breast cancer cells comparing the activities of preformed and in situ coronas showed different uptake behaviors, suggesting the role of protein corona formation in promoting the interaction between the SPIONs and the cells. The results obtained here provide the essential information for further development of the potential strategy to reduce or stimulate immune response in vivo to increase therapeutic applications of both C-SPIONs and Rf-SPIONs.

BackgroundThe pteropine orthoreovirus (PRV) was isolated from monkey (Macaca fascicularis) faecal samples collected from human-inhabited areas in Lopburi Province, Thailand. These samples were initially obtained to survey for the presence of hepatitis E virus (HEV).ResultsTwo virus isolates were retrieved by virus culture of 55 monkey faecal samples. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was successfully used to identify the viruses as the segmented dsRNA orthoreovirus. Phylogenetic analysis of the Lopburi orthoreovirus whole-genomes revealed relationships with the well-characterised PRVs Pulau (segment L1), Cangyuan (segments L2, M3 and S3), Melaka (segments L3 and M2), Kampar (segments M1 and S2) and Sikamat (segments S1 and S4) of Southeast Asia and China with nucleotide sequence identities of 93.5–98.9%. RT-PCR showed that PRV was detected in 10.9% (6/55) and HEV was detected in 25.5% (14/55) of the monkey faecal samples.ConclusionsPRV was isolated from monkey faeces for the first time in Thailand via viral culture and LC-MS/MS. The genetic diversity of the virus genome segments suggested a re-assortment within the PRV species group. The overall findings emphasise that monkey faeces can be sources of zoonotic viruses, including PRV and HEV, and suggest the need for active virus surveillance in areas of human and monkey co-habitation to prevent and control emerging zoonotic diseases in the future.Electronic supplementary materialThe online version of this article (10.1186/s12866-018-1302-9) contains supplementary material, which is available to authorized users.

Schistosomiasis remains a global health problem. In the Mekong river basin, approximately 80,000 people are at risk of infection by Schistosoma mekongi. The parasite's eggs become entrapped in the host's organs and induce massive inflammation, contributing to the pathogenesis of schistosomiasis. In addition, egg antigens are important in circumoval precipitin tests (COPTs) and other diagnostic techniques. Little is known regarding the egg proteins of S. mekongi, and so we applied immunoblotting and mass spectrometry-based proteomic approaches to study these proteins and their antigenicity. A total of 360 unique proteins were identified in S. mekongi eggs using proteomic analyses. The major protein components of S. mekongi eggs were classified into several groups by functions, including proteins of unknown function, structural proteins, and regulators of transcription and translation. The most abundant proteins in S. mekongi eggs were antioxidant proteins, potentially reflecting the need to neutralize reactive oxidative species released from host immune cells. Immunomic analyses revealed that only DNA replication factor Cdt1 and heat shock protein 70 overlap between the proteins recognized by sera of infected mice and humans, illustrating the challenges of knowledge transfer from animal models to human patients. Forty-one immunoreactive protein bands were recognized by either mouse or patient sera. Phosphoglycerate kinase, fructose-1,6-bisphosphate aldolase and elongation factor 1 appeared to be interesting immunogens of S. mekongi eggs as these proteins were recognized by polyclonal IgMs and IgGs in patient sera. Our findings provide new information on the protein composition of S. mekongi eggs as well as the beginnings of a S. mekongi immunogen dataset. These data may help us better understand the pathology of schistosomiasis as well as natural antibody responses against S. mekongi egg proteins, both of which may be useful in including S. mekongi to other schistosoma diagnostic, vaccine and immunotherapy development.