Leishmania Infection: A Bioorganic Model Under the Light of Benchtop Low Field Nuclear Magnetic Resonance

Low-field benchtop Nuclear Magnetic Resonance (NMR) spectrometers rely on permanent magnets and do not require deuterated solvents, being increasingly employed for quality control and the profilometric assays of complex matrices from food products to metabolically enriched exudates. In this study, the non-destructive, non-invasive, low-cost and time-effective nature of benchtop NMR investigations was exploited to separate Leishmania infantum -positive and -negative dog (Canis lupus familiaris) sera. Moreover, among the Leishmania-positive samples, sera with either circulating free or complexed antibody molecules displayed distinctive NMR profiles with promising discriminatory potential. This approach is made possible by the identification of specific bioorganic 1D and 2D NMR signals, such as protons found in pyranose (PYR), phospholipid (SPC), and acetyl moieties (Glyc), whose distribution in serum samples varies in association with specific parasitic infections. The discrimination among Leishmania Negative (n=5) vs Low positive (n=8) samples was successfully performed using the summed integration areas of 3 main buckets (SPC, Glyc, late PYR), while the analytical speciation of High (Ab+) positive (n=8) samples was reached recurring to a further integrated area, belonging to early PYR signals. The characterization of inflammatory states through traces of oxidized lipids, and the study of immunological activation using bioorganic signals of glycoproteins, can be easily exploited on a broad scale even in different pathological contexts with features similar to the Leishmania case report.