Application of imprint cytology in assessment of immunological effects of isolated and combined action of selenium and copper nanoparticles

Introduction. Touch Imprint Cytology as the method of impression cytology of smears-prints is of great diagnostic value not only in clinical practice but is also of interest as an express method for assessing the immunological effects of the influence of metal-containing nanoparticles on the tissues of laboratory animals in an experiment.

Materials and methods. The study involved the spleen and mesenteric lymph nodes (MLN) of outbred male rats (24 individuals), with an initial weight of 220–230 g, after subchronic intoxication, which was caused by repeated intraperitoneal injections of metal-containing nanoparticles of selenium (SeO) and copper (CuO) nanoparticles (NPs) at a dose of 0.5 mg/kg and their combination three times a week (a total of 18 injections). After sacrificing the rats by decapitation, the spleen and MLN were removed from the animals from each group; made smears were dried at room temperature. Stained according to Leishman. Cell composition and cytological signs were assessed in a light binocular microscope by Carl Zeiss Primo Star with a USCMOS video imaging system at a magnification of 100x and 1000x under cytological criteria. Cell counting in the analysis of spleen and MLN preparations was carried out in percentage — 100 cells from each smear (48 studies), as well as calculating the number of cellular elements per 1 mm² of the smear surface area, by calculating the absolute amount of each cellular element in the microscope field of view of 0.03 mm², followed by recalculation per 1 mm² (the number of studies is 48). Differences between the mean group quantitative results were processed using Student’s criteria using Excel software. Differences between mean values ​​were considered statistically significant if the probability of a random difference did not exceed 5% (р < 0.05).

Results. The main results obtained in the study of cytomorphological parameters of smears — spleen prints and MLN of rats after exposure to SeO and CuO NPs, both independently and their combination using two methods for calculating the cellular composition of preparations, are presented. The main changes in the cellular composition during immunological effects are highlighted. Inflammatory reactions of the hyperergic type were revealed when exposed to selenium nanoparticles, both in autonomous action and in combination with copper nanoparticles. The formation of local cellular immunity was noted due to an increase in the level of plasma cells in smears imprints when exposed to copper nanoparticles.

Conclusion. Using the impression method of smears-prints in conjunction with the histological examination of tissue preparations allows implementing complete cytomorphological parameters in studying the immunological effects of metal-containing nanoparticles.

Contribution:

Bushueva T.V. — design of the study, text writing;

Sakhautdinova R.R. — data collection, data processing, text writing;

Riabova Iu.V. — the collection and processing of the material;

Panov V.G. — statistics;

Sutunkova M.P., Minigalieva I.A. — editing.

All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

The conclusion of the committee on biomedical ethics: the Local Ethics Committee of the Yekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial Workers, Russian Agency for Consumer Rights Protection, Yekaterinburg, 620014, Russian Federation approved this study, protocol number 2 of 20.04.21.

Conflict of interest. The authors declare no conflict of interest.

Acknowledgement. The study had no sponsorship.

Received: October 6, 2021 / Accepted: November 25, 2021 / Published: December 30, 2021