THE RELEVANCE OF USING THE SOFTWARE PACKAGE R-MALDIQUANT FOR THE CONVERSION OF RAW MAA-SPECTRA OF DIROFILARIA

Abstract

Diagnosis of human tissue helminthiasis remains a complex problem of practical medicine. Therefore, the search for alternative direct methods of their verification is an important area of laboratory diagnostics. Proteomic research methods are one of the most modern areas of laboratory practice. Updating the database of reference protein profiles of parasitic pathogens is one of the main priorities of mass spectrometry. To convert digital data of protein extract spectra, the R-MALDIquant software package for dirofilaria differentiation (Dirofilaria immitis, Dirofilaria repens) was used. For the study, two D. repens females were taken, removed from the subcutaneous fat of two patients (one from each patient), two D. immitis females obtained from the heart after autopsy of two fallen dogs. In the study, only the head ends were taken (where the stichocytes are concentrated), without reproductive organs (where the main excretory-secretory antigens of the parasite are located). The profiles of the mass spectra of the homogenate proteins were obtained using the standard Sepsityper Kit 50 and the “Formic Acid Extraction” for Microflex LT MALDI–TOF MS (Bruker Daltonics) with flexControl software (Bruker Daltonics). Visualization was performed using Flexanalysis 3.3 software (Bruker Daltonics). Preliminary processing of mass spectra was carried out using the R software environment in the MALDIquant package. The coincidence rate in the dendrogram sections for D. immitis individuals was 96-99 %, and for D. repens – 73-100 %, which is probably due to phenotypic differences in helminths isolated from different patients. The results obtained by us of processing two types of dirofilaria using the R-MALDIquant software environment are the first step in creating a library of reference protein profiles of nematodes of the genus Dirofilaria. Key words: Dirofilaria repens, Dirofilaria immitis, MALDI-TOF MS, R package, MALDIquant. erroneous identification of the causative agent of the disease D. latum, which did not affect the results of treatment