UDC: 616.94:576.8.06:616.155.34:616.155.321]-002.828-092.9

   Background. Sepsis is a major global health problem, with fungal pathogens such as Candida albicans emerging as a significant cause of invasive infection. Fungal sepsis has a higher mortality rate than bacterial sepsis and is complicated by antifungal resistance. Although neutrophil extracellular traps (NETs) help to contain fungi, excessive NETs can contribute to inflammation and tissue injury. Understanding these mechanisms could reveal markers of disease activity and new therapeutic targets. Materials and Methods. Fungal sepsis was induced in twelve male BALB/c mice via an intraperitoneal injection of Meyerozyma guilliermondii (107 cells per mouse). Blood was collected at the beginning of the study and then on days 1–3, 7–9, and 13–15. Serum was analyzed for IgG, IgM, circulating immune complexes (ELISA), and extracellular DNA (fluorescence assay). 
   Results and Discussion. In mice with fungal sepsis, IgG levels remained stable while IgM levels increased significantly between days 7 and 9, before declining from day 13. IgG–IgM immune complexes peaked around days 8–9, reflecting active antigenantibody responses. Free DNA levels, which indicate NETs formation, increased by day 7 and then declined, showing early neutrophil activation followed by humoral control. Together, these findings suggest a coordinated immune response in which NETs and immune complexes contribute to both pathogen control and inflammation.
   Conclusion. Fungal sepsis induced by Meyerozyma guilliermondii resulted in early NETosis and an increase in IgM and immune complexes. IgM levels peaked on days 7–9 before declining. Unlike Candida albicans, this strain does not cause rapid lethality, enabling detailed tracking of disease progression over time. After day 9, immune parameters began to normalize, indicating the resolution of the acute phase and supporting the usefulness of this model for studying host immune dynamics in fungal sepsis.
   Keywords: fungal sepsis, Meyerozyma guilliermondii, acute inflammation, immune defense, circulating immune complexes, neutrophil extracellular traps
(NETs)

UDC 577.615.324-027.2.615.076

   Creation of novel remedies efficient in supporting wound healing remains an actual task in pharmacology. Hydrogels showed high efficiency in wound healing and tissue regeneration due to viscosity, elasticity and fluidity that provide them with functional characteristics similar to that in extracellular matrix. The aim of the study was to create chitosan-based hydrogels functionalized with different components (chondroitin-6-sulfate, hyaluronic acid, N-stearoylethanolamine) and to estimate their biocompatibility and biodegradability in vitro. For the first time, a lipid substance N-stearoylethanolamine (NSE) known as suppressor of pro-inflammatory cytokines expression was used as hydrogel component (1.95 mg/g). FTIR analysis confirmed the complexation of chitosan molecule with hyaluronate, chondroitin-6-sulfate, NSE. MTT-test and Trypan blue exclusion test were used to study hydrogels cytotoxicity towards human cells of different tissue origin. Biodegradability of hydrogels was evaluated using direct hydrogel contact with cells and cellindependent degradation. It was shown that chondroitin-6-sulfate (<2 mg/ml), hyaluronic acid (<2 mg/ml) and NSE (26 μg/ml) did not demonstrate significant toxic effects towards pseudonormal human cells of the MCF10A, HaCat, HEK293 lines and mouse cells of the Balb/3T3 line. The studied hydrogels were stable in saline solution, while in a complete culture medium containing 10% fetal bovine blood serum they underwent degradation in >24 h. The identified biodegradability of the chitosan-based hydrogels is important for the release of noncovalently immobilized NSE into biological medium. Further studies on laboratory animals with experimental wounds are expected to explore the potential of created hydrogels as anti-inflammatory
and wound-healing agents.
K e y w o r d s: chitosan hydrogels, chondroitin-6-sulfate, hyaluronic acid, N-stearoylethanolamine, FTIR analysis, human pseudonormal cells, toxicity, biodegradability


Колективом кафедри гістології, цитології та ембріології Львівського національного медичного університету імені Данила Галицького укладений ілюстрований посібник, метою якого є допомогти студентам при самопідготовці та на практичних заняттях у вивченні мікроскопічних препаратів клітин, тканин і органів, інтерпретації отриманих зображень та опануванні специфічної гістологічної та ембріологічної термінології. Запропонована структура посібника покликана допомагати студентам у вивченні матеріалу, а також підготуватися до здачі іспиту з гістології, цитології та ембріології. Навчальний посібник обговорено та затверджено на засіданні профільної методичної комісії з медико-біологічних дисциплін
Протокол № 4 від 30 серпня 2022 року