Dominika Nguyen Ngoc

Excessive inflammation following implant insertion may impair early healing and predispose to postoperative complications. Since neutrophils constitute the predominant leukocyte population during the initial inflammatory phase, and monocytes subsequently orchestrate tissue resolution and repair, understanding their direct response to biomaterials and bioactive compounds is essential. In the present study, we evaluated the effect of purified bioactive extract combined with biomaterial on neutrophil and monocyte activity in vitro, comparing their modulatory potential with that of non-purified extract. Porcine neutrophils and monocytes were cultured in contact with hydroxyapatite (HA) mixed with purified fractions obtained through sequential chromatographic isolation. Cellular responses were assessed by measuring enzyme release and reactive oxygen/nitrogen species (ROS/RNS) generation. Neutrophils exposed to HA alone displayed a pronounced oxidative response, confirming strong activation. Purified extracts, however, significantly reduced ROS/RNS production (NO: 2.71 ± 0.07 µM vs. HA-only group 5.72 ± 0.10 µM, p < 0.05), whereas non-purified extracts elicited only a partial reduction. Enzyme release followed the same trend, with purified fractions demonstrating a markedly higher inhibitory effect on neutrophil degranulation. Similarly, monocytes exposed to HA exhibited prolonged oxidative stress at 24 h and 48 h, which was markedly downregulated by the purified extract (HA + EX), demonstrating significant reductions in both nitric oxide (NO) and superoxide generation. These findings indicate that purification enhances the bioactivity and specificity of the tested extracts, improving their capacity to modulate excessive neutrophil and monocyte activation. To address this challenge, this study introduces a novel, advanced purification method designed to isolate and refine AMPNE-type particles from the crude extract. Furthermore, we investigated whether the purified particles retain their structural and functional integrity post-purification. By comparing the biological efficacy of the extract before and after purification, we evaluated whether the cleaning process maintains, enhances, or modifies their original bioactive properties, providing crucial insights into the viability of the proposed technology. Our study highlights the potential of purified bioactive molecules to more effectively regulate early inflammatory responses to biomaterials. These results provide a foundation for further research into targeted immunomodulatory strategies aimed at improving implant integration and reducing inflammatory complications.

Ozone (O₃) is a reactive oxidant increasingly applied in biomedical settings, yet its dose-dependent effects on innate immune cells, particularly those from non-human species, remain insufficiently defined. Within a One Health framework, this study examined how two clinically relevant O₃ exposure regimens (30 µg/mL and 90 µg/mL) affect porcine neutrophils and monocytes isolated from peripheral blood. Cell viability, reactive oxygen and nitrogen species (RONS) production, and the activity of key enzymes (myeloperoxidase, elastase, alkaline phosphatase, arginase) were assessed at 1 h and 24 h post-exposure. The lower dose induced mild functional activation without compromising viability, whereas the higher dose triggered pronounced oxidative stress, enhanced degranulation, and reduced neutrophil viability by more than 60%. Neutrophils exhibited a stronger and more dynamic response than monocytes, which retained viability and differentiation capacity at 30 µg/mL but showed impaired function at 90 µg/mL. These findings highlight the dual nature of O₃, where controlled exposure may support immunomodulation, while excessive dosing disrupts cell function. Defining safe and effective therapeutic windows remains critical for future applications.

Osteomyelitis, a severe bone infection, poses a significant therapeutic challenge in both human and veterinary medicine, especially due to the increasing prevalence of antibiotic-resistant pathogens like methicillin-resistant Staphylococcus aureus (MRSA). Conventional treatments, including surgical debridement and systemic antibiotics, often prove inadequate due to the ability of bacteria to form biofilms and evade host immune responses. Antimicrobial peptides (AMPs), such as LL-37 and β-defensins, have emerged as a promising alternative therapeutic strategy. AMPs exhibit broad-spectrum antimicrobial activity, including efficacy against resistant strains, and possess immunomodulatory properties that can promote bone regeneration. This article comprehensively reviews AMP applications in treating osteomyelitis across both human and veterinary medicine. We discuss diverse therapeutic approaches, including free AMPs, their conjugation with biomaterials such as collagen and chitosan to enhance delivery and stability, and the development of AMP-based nanoparticles. Furthermore, we analyze preclinical and clinical findings, highlighting the efficacy and safety of AMPs in combating osteomyelitis in both human and animal patients. Finally, we explore future perspectives and challenges, such as optimizing delivery, stability, and efficacy, while minimizing cytotoxicity, and in translating AMP-based therapies into clinical practice to effectively manage this debilitating disease.

Background: Protein adsorption on medical devices in contact with blood is a significant issue during renal replacement therapy. Main forces determining fouling are the electrostatic interactions between membrane and charged protein, but the dialysis membrane surface charges can be adjusted by modifying the polymer matrix to decrease the blood plasma protein adsorption. Methods: In this study, polysulfone membranes (PSU) were modified by incorporation of carbon nanoparticles such as: multiwall carbon nanotubes (2 wt.% MWCNT), graphene oxide (1 wt.% GO), and graphite (5 wt.% GR) during manufacturing process (nonsolvent-induced phase separation, NIPS). The PSU flat sheet membrane was the reference sample. Results: Observed morphology of nanocomposite membranes was similar (SEM imaging); all of them had finger-like pore structure with unimodal distribution of pore size and similar skin-to-support ratio (1:3). The carbon nanoadditives also influenced the surface wettability: hydrophobicity and surface free energy of membranes increased (polar components of energy were reduced, while the dispersive components were increased). Conclusion: The surface charge of nanocomposite membranes increased, when the polymer matrix has been modified with CNT or GR. This significantly affects the adsorption of proteins such as chicken (CSA) and bovine serum albumin (BSA) and reduces blood clotting on the membrane.

Introduction: Macrophages are crucial immune cells that play a role in tissue repair and can exhibit pro- or anti-inflammatory behaviour based on environmental stimulation. Their functional phenotype can be affected by platelet-derived products as determined by those products’ composition. When the inflammatory response caused by implantation is excessive, it can lead to rejection of the implant. Therefore, a thorough evaluation of implant haemocompatibility is necessary to minimise undesirable consequences. Material and Methods: In an in vitro study, monocyte-derived macrophages (MDMs) were obtained from the whole blood of sheep after a silicon-doped diamond-like carbon–coated implant insertion. These MDMs were then exposed to autologous platelet-derived products for functional marker analysis. Results: Platelet-poor plasma (PPP) and pure platelet-rich plasma (P-PRP) stimulation increased arginase-1 activity, while leukocyte-rich PRP stimulation produced a mixed response involving higher O₂ ⁻ (6.49 ± 2.43 nM vs non-stimulated 3.51 ± 1.23 nM, P-value < 0.05) and NO (3.28 ± 1.38 μM vs non-stimulated 2.55 ± 0.32μM, P-value < 0.05) generation. Conclusion: Using PPP and P-PRP stimulation in post-implantation procedures may contribute to the polarisation of macrophages towards the M2-like pro-resolving phenotype, thereby accelerating wound healing. This would also prevent implant degradation due to an excessive inflammatory process.

Neutrophils play a pivotal role in both the inflammatory phase and subsequent repair processes, making their activity crucial after contact with biomaterials. Excessive neutrophil activation can lead to complications, including implant rejection, highlighting the importance of modulating their activity. This study investigates the long-term interaction of circulating ovine neutrophils with titanium (Ti) and silicon-doped layer (Si-DLC) coated implants. Additionally, the effects of platelet-rich plasma (PRP), platelet-poor plasma (PPP), and antimicrobial neutrophil crude extract (ANE) on neutrophil activity were assessed. Twelve female sheep were divided into Ti, Si-DLC implant and a control group. Neutrophils were stimulated with PRP, PPP, ovine ANE (oANE), or rabbit ANE (rANE), and their enzymatic activity and reactive oxygen and nitrogen species (RONS) generation were evaluated. Hematological parameters were also analyzed. Results showed no adverse effects at implant sites, and all hematological parameters remained within reference values. Ti and Si-DLC implants did not alter neutrophil activity. PRP significantly increased neutrophil activity and RONS production, while PPP decreased activity. oANE reduced enzymatic activity and RONS generation, indicating potential antiinflammatory effects. rANE showed varied effects on neutrophil function. Both ANEs lacked antimicrobial activity against tested pathogens. This study demonstrates the hemocompatibility of Ti and Si-DLC implants and highlights the potential of blood-derived products in modulating the inflammatory response to implants.

Implant insertion can evoke excessive inflammation which disrupts the healing process and potentially leads to complications such as implant rejection. Neutrophils and macrophages play a vital role in the early inflammatory phase of tissue repair, necessitating the study of cellular responses in host–implant interactions. In order to deepen the knowledge about these interactions, the response of neutrophils and macrophages to contact with selected biomaterials was examined in vitro on the basis of secretory response as well as reactive oxygen species/reactive nitrogen species (ROS/RNS) generation. Porcine neutrophils exposed to hydroxyapatite (HA) released more enzymes and generated higher levels of ROS/RNS compared to the control group. The addition of AMPNE diminished these responses. Although the results from porcine cells can provide valuable preliminary data, further validation using human cells or clinical studies would be necessary to fully extrapolate the findings to human medicine. Our study revealed that human neutrophils after contact of with HA increased the production of nitric oxide (NO) (10.00 ± 0.08 vs. control group 3.0 ± 0.11 µM, p < 0.05), while HAP or FAP did not elicit a significant response. Human macrophages cultured with HA produced more superoxide and NO, while HAP or FAP had a minimal effect, and curdlan reduced ROS/RNS generation. The addition of AMPNE to cultures with all biomaterials, except curdlan, reduced neutrophil activity, regardless of the peptides’ origin. These results highlight the potential of antimicrobial peptides in modulating excessive biomaterial/host cell reactions involving neutrophils and macrophages, enhancing our understanding of immune reactions, and suggesting that AMPNE could regulate leukocyte response during implantation.

The pathologically changed pattern of gonadotropin secretion, responsible for ovulation disorders in fatty ewes, may result from the prolonged increase in leptin concentration as well as from diminution of leptin receptors expression in anterior pituitary cells. Leptin acting peripherally reduces the secretion of insulin – the potent inhibitor of lipolysis. Consequently, an increment in plasma fatty acids level is observed. It was also found that in ewe lambs born to obese sheep carrying twins or triplets, a high plasma level of saturated fatty acids (SFA) is in positive correlation with the delay in puberty. However, the relationship between SFA and gonadotropin secretion from the ovine pituitary cells in pubescent ewe lambs is not clear. Therefore, the aim of the study was to establish the effect of SFA on GnRH-induced secretion of FSH and LH. Pituitary glands were isolated from 7 month old ewe lambs. Pituitary cells were cultured in McCoy 5A medium without GnRH and SFA (negative control), with GnRH only (positive control), with GnRH and 10–9-10–3 M/l of the butyric (C4:0), caprylic (C8:0), lauric (C12:0), palmitic (C16:0) or stearic acid (C18:0). After 2 or 6 h of exposure to SFA followed by 2, 6, 12, 18, 24 or 30 h incubation, the media for LH and FSH analysis were collected. It was found that all used SFA reduce GnRH-induced LH and FSH secretion from pituitary cells in vitro. The most significant (P ≤ 0.05) suppressive effect was observed after 6 h exposure of cells to 10–3 M/l of caprylic acid, 10–4 M/l of palmitic acid and 10–4 M/l of stearic acid compared to the positive control.

The aim of this review is to present information about leukemia caused by feline leukemia virus (FeLV) infection in felids. Despite widespread vaccinations, leukemia is still one of the most common diseases in cats. FeLV infection occurs by direct contact between animals, especially through contact with saliva. Infection with this highly contagious virus is characterized by immunosuppression and non-specific signs, such as cytopenia or tumorigenesis. The virus is transmitted horizontally through close contact between cats and vertically from infected queens to their kittens. Persistently infected cats are the reservoir of the virus. Rapid ELISA tests and immunochromatography play a major role in diagnosis, but RT-PCR is the most reliable diagnostic method. There is no specific therapy against FeLV, so treatment is mainly symptomatic. Research on the use of antiviral drugs, i.e. tenofovir, raltegravir, and fozyvudine, is underway. Proper prophylaxis, including regular vaccination of animals, is important to minimize the risk and consequences of infection