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1

Wpływ nanocząstek metali szlachetnych na układ immunologiczny zwierząt

100%
Malaczewska J.
Medycyna Weterynaryjna
|
2014
|
tom 70
|
nr 04
Noble metal nanoparticles, especially silver due to its antimicrobial properties, are amongst the most widely used types of nanomaterials, and so the possibility of an organism’s exposure to them is relatively high. Excluding injections, there are three natural routes they can accidentally enter the body – the skin, lungs and the alimentary tract. Research on rodents indicate that after inhalation, injection or oral administration silver, gold and copper nanoparticles can easily enter the systemic circulation and reach the internal organs. Particularly vulnerable to the harmful effects of nanoparticles are organs with an extended reticuloendothelial system, such as the spleen, where the accumulation of nanoparticles occurs. It is well proved that metallic nanoparticles are easily absorbed by macrophages located in lymphoid tissues but cannot be destroyed inside the cells. They remain unchanged in phagosomes and chronically stimulate the cells to pro-inflammatory cytokine production. They can also interact with other cell types present in the local environment, e.g. lymphocytes, which can lead to an inadequate immunological response of the organism. Many authors have described the pro-inflammatory effect of noble metal nanoparticles, both local to the application site and generalized. What is more, silver nanoparticles were able to disturb the Th1/Th2 balance or even cause an allergic response of the organism. The beneficial impact of silver nanoparticles on the immune response occurs only when they were applied externally in the form of dressings or ointments in the treatment of wounded or inflamed skin. In such cases nanosilver exhibited immunoregulatory properties accelerating the healing. An explanation for this mode of action may be the fact of relatively poor skin penetration by nanoparticles, limiting their effect to the local tissues only.
2
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The in vitro effect of commercially available noble metal nanocolloids on the splenocyte proliferative response and cytokine production in mice

100%
Malaczewska J.
Polish Journal of Veterinary Sciences
|
2014
|
tom 17
|
nr 1
Noble metal nanoparticles, currently among the most popular types of nanomaterials, are capable of penetrating through biological barriers once they enter a living organism. There, they can permeate into organs possessing the reticuloendothelial system, such as the spleen. The objective of this study was to determine the effect of commercial nanocolloids of noble metals (silver, gold and copper), recommended by the manufacturer as dietary supplements, on the in vitro viability, proliferative activity and production of cytokines (IL-1β, IL-2, IL-6, IL- 10 and TNF-α) by mouse splenocytes. All of the analyzed colloids had some effect on the activity of mouse splenocytes. Silver colloid was characterized by high toxicity - concentrations of 1.25 ppm and above substantially depressed the viability of cells as well as their proliferative activity and ability to synthesize cytokines. The other two colloids were far less toxic than nanosilver, although their non-toxic concentrations had a significant effect on the production of cytokines by mitogen activated splenocytes. The colloid of gold decreased the level of IL-2, and the colloid of copper caused an increase in IL-2, IL6 and Il-10. At the same time, copper colloid alone induced the synthesis of IL-1β in mitogen unstimulated cells. The results indicate that colloids of noble metals are capable of affecting the activity of immunocompetent cells in important peripheral organs of the immune system.
3
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Effect of 28-day oral administration of silver nanocolloid on the peripheral blood leukocytes in mice

100%
Malaczewska J.
Polish Journal of Veterinary Sciences
|
2014
|
tom 17
|
nr 2
Silver nanoparticles, which have found a wide range of applications owing to their antimicrobial properties, are also recommended as dietary supplements in alternative medicine. Studies on rodents confirm that nanosilver is absorbed from the digestive tract into the bloodstream, which implies its possible interactions with leukocytes. The objective of the experiment discussed herein has been to determine the effect of 28-day oral administration of different doses (0.25, 2.5, 25 ppm) of commercial silver nanocolloid on hematological parameters, percentages of particular lymphocyte populations and activity of the peripheral blood leukocytes in mice. All the tested colloid doses decreased the counts of monocytes in the animals’ blood and induced phenotypic modifications among lymphocytes: an increase in CD4+/CD8+ T cell distribution, a decrease in NK and NKT cell distribution (doses of 0.25 and 2.5 ppm) and an increased CD4+:CD8+ ratio (25 ppm). Silver nanocolloid also affected the activity of cells, depressing the proliferation of lymphocytes (0.25 ppm) and stimulating phagocytosis as well as the respiratory burst of granulocytes and monocytes (all doses). The results verify the influence of orally administered silver colloid on the peripheral blood leukocytes, at the same time implying the potential risk of developing an inappropriate immune response of an organism exposed to prolonged administration of this substance.
4
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The effect of silver nanoparticles on splenocytes activity and selected cytokine levels in the mouse serum at early stage of experimental endotoxemia

100%
Malaczewska J.
Polish Journal of Veterinary Sciences
|
2011
|
tom 14
|
nr 4
The objective of this study was to determine the effect of a nonionic silver nanocolloid administered orally for 7 or 14 days at three concentration levels (25 ppm, 2.5 ppm, and 0.25 ppm) on the phagocytic activity and mitogenic response of splenocytes and selected cytokine serum levels (IL-1β, IL-6, IL-10, IL-12 p70, TNF-α) in NMRI mice at the early stage of experimental endotoxemia induced with single 30 μg/mouse dose of bacterial LPS. Regardless of the period of administration, silver nanoparticles enhanced the production of proinflammatory cytokines and anti-inflammatory cytokine IL-10, and they inhibited IL-12 p70 levels in response to LPS challenge. The studied nanoparticles' effect on splenocyte activity was determined by the period of administration. After 7 days of use, silver nanoparticles enhanced the phagocytic activity, and doses of 2.5 ppm stimulated the mitogenic response of splenocytes. After 14 days of administration, silver nanoparticles lowered the phagocytic activity regardless of the dose applied. Although the results obtained are ambiguous, they suggest that silver nanoparticles administered via the alimentary tract are more likely to increase an inflammatory response of an organism than offer protection after LPS challenge.
5
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The splenocyte proliferative response and cytokine secretion in mice after 28-day oral administration of silver nanocolloid

100%
Malaczewska J.
Polish Journal of Veterinary Sciences
|
2014
|
tom 17
|
nr 1
An increasing number of applications of silver nanoparticles in industry, medicine and everyday life means that the risk of exposure of the human organism to their potential harmful influence is growing. This study has sought to assess the effect of 28-day alimentary administration of different concentrations (0.25, 2.5 and 25 ppm) of a commercial silver nanocolloid on the proliferative activity and synthesis of cytokines by mouse splenocytes. All of the analyzed doses of the colloid had a significant, albeit different, effect on the activity of splenocytes. At the lowest dose, a significant decrease in the proliferation of T cells and more intensive synthesis of pro-inflammatory cytokines, both by non-stimulated and LPS-stimulated cells, was observed. The intermediate dose, on the other hand, stimulated proliferation of B cells while producing a pro-inflammatory effect regarding the synthesis of cytokines. Finally, the highest dose decreased the synthesis of cytokines by non-stimulated cells, but after LPS stimulation, through the strong activation of the IL-10 synthesis, it raised the proliferation of B cells and decreased the synthesis of pro-inflammatory cytokines. The results suggest that silver nanoparticles administered orally have an easy access to the peripheral organs of the immune system, such as the spleen, but the effect of long-term exposure of this organ to the effect of silver nanocolloid depends on several factors, including the dose of nanoparticles, and seems as difficult to predict.
6

Cytotoksyczność nanocząsteczek srebra

100%
Malaczewska J.
Medycyna Weterynaryjna
|
2010
|
tom 66
|
nr 12
s.833-838,bibliogr.
Nanotechnology concerns the study, creation and manipulation of structures, devices, and systems at a nanoscale level. Such materials exhibit unique biological, physical and chemical properties compared to bulk materials, and are readily utilized in modern medicine and industry. Currently silver nanoparticles (SNP) are among the most commonly used nanomaterials due to their antimicrobial properties. Nanosilver can be found in medical devices, filters for water purification and in many consumer products as well. However, some recent studies indicate that nanosilver formulations may be cytotoxic to various types of both animal and human cells. Because their size is similar to cellular components they are able to bypass cell membranes, which results in cytotoxicity, although the exact mechanism of such an interaction is yet to be established. Several studies have reported the accumulation of SNP inside cells and their impact on cell morphology, while many of them claim that nanosilver induces cell necrosis or apoptosis due to decreasing function of mitochondria and catalyzes the production of reactive oxygen species, which leads to oxidative stress. Some reports indicate NPS can affect the physiology of immune competence and even of stem cells, which is of great importance for such crucial biological phenomena as the immunity and fertility of organisms. Taking into consideration all of the above and the fact of growing exposure of human bodies to increasing doses of nanoparticles, there is a real need for evaluating the potential risks of using nanosilver in our everyday lives.
7

Wpływ nanocząsteczek srebra na żywotność i aktywność proliferacyjną jednojądrzastych leukocytów krwi obwodowej i splenocytów mysich - badania in vitro

100%
Malaczewska J.
Medycyna Weterynaryjna
|
2010
|
tom 66
|
nr 12
s.847-851,tab.,bibliogr.
Silver nanoparticles (SNP) have been recently one of the most widely utilized nanomaterials, mostly because of their antimicrobial activity. For some time there has been a great interest in SNP of unconventional medicine, which recommends their use not only as an antimicrobial, but also as an immunostimulant. However, little is known about SNP’s impact on immunocompetent cells in vitro. The aim of a present study was to investigate the influence of the colloidal nano-silver solution on the viability and proliferative response of mice peripheral blood mononuclear leukocytes and splenocytes in vitro. After isolation cells were cultured in complete RPMI-1640 medium containing 0 (control), 20, 10, 5, 2, 1, 0.5, 0.2, 0.1 and 0.05 ppm of SNP, for 24 and 48 h to investigate SNP’s impact on cell viability, and for 72 h to evaluate their effect on the proliferative response of cells. Both parameters were assessed using MTT assay. Obtained results suggest that SNP have significant influence on the both investigated parameters. High doses of SNP significantly decreased (p < 0.01) the viability (concentrations of 5-20 ppm for splenocytes and 2-20 ppm for leukocytes, respectively) and proliferative response of cells (splenocytes: 5-20 ppm, leukocytes: 10-20 ppm) whereas low SNP’s doses slightly increased (p > 0.05) the viability of cells (splenocytes: 1 ppm, leukocytes: 0.2 ppm) and significantly increased stimulation index of both cell types induced by mitogens (splenocytes: 0.2-0.5 ppm, p < 0.05; leukocytes: 0.1-0.5 ppm, p < 0.01). These experimental data constitute an encouragement for further investigations concerning the possibility of therapeutic use of SNP’s low doses.
8
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Effect of oral administration of commercial gold nanocolloid on peripheral blood leukocytes in mice

100%
Malaczewska J.
Polish Journal of Veterinary Sciences
|
2015
|
tom 18
|
nr 2
During the last few decades, owing to their unique properties, gold nanoparticles (AuNPs) have found numerous biomedical applications. Studies on rodents prove that AuNPs entering an organism easily reach the bloodstream and undergo wide tissue distribution. The presence of nanoparticles inside blood and bone marrow cells of exposed animals may implicate its influence on hematopoesis and the functions of peripheral blood leukocytes. The aim of this study was to determine the effect of oral administration of commercial gold nanocolloid, recommended by the producer as a dietary supplement, on the percentage of lymphocyte populations and proliferative response, as well as the activity of phagocytes in the peripheral blood of mice. The colloid was given to the animals in three different doses (0.25, 2.5, 25 ppm), for three different time periods (7, 14, 28 days). Mice given nanoparticles showed increased activity of phagocytes and some changes in the lymphocyte phenotypes. The elevated activity of granulocytes and monocytes, in terms of both phagocytic and respiratory burst activity, was transient and noticed only after a short time of administration, which may indicate some adaptability of blood phagocytes to prolonged presence of gold nanoparticles in the body. However, phenotypic modifications among lymphocytes in the group of animals given the middle dose of colloid (i.e. increased percentage of B and CD4+CD8+ DP T cells) did not occur until after the 28-day administration, which in turn seems indicative of some immune dysregulation due to the prolonged contact with nanogold.
9
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The splenocyte proliferative response and cytokine secretion in mice after oral administration of commercial gold nanocolloid

100%
Malaczewska J.
Polish Journal of Veterinary Sciences
|
2015
|
tom 18
|
nr 1
Owing to their unique physicochemical properties, gold nanoparticles find numerous biomedical applications. Experiments on rodents prove that the main target organs of gold nanoparticles entering an organism are the liver and spleen, whose reticuloendothelial system removes foreign particles from the bloodstream. Through interactions with resident tissue macrophages, nanoparticles can evoke a systemic immunological response. The aim of this study has been to determine the effect of oral administration of commercial gold nanocolloid, recommended by the producer inter alia as a dietary supplement, on the proliferative activity and cytokine secretion by murine splenocytes. The colloid was given to the animals in three different doses (0.25, 2.5, 25 ppm), for three different time periods (7, 14, 28 days). The influence of nanogold on splenocyte functions was time-dependent and the various doses were distinguished by distinct modes of action. The lowest dose had a pro-inflammatory or immunostimulating effect, enhancing the synthesis of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-a). The effect of the highest dose can be considered as a pro-inflammatory, or immunotoxic one, because the stimulated cytokine synthesis was accompanied by a drastic decline in the proliferative activity of lymphocytes. The medium dose, while inhibiting the synthesis of pro-inflammatory cytokines of macrophages, simultaneously stimulated the proliferation of lymphocytes. All the doses also modulated the synthesis of IL-2, which may implicate their effect on the immunoregulatory mechanisms of an organism. The effect of alimentary administration of gold nanocolloid on the immune system seems to be difficult to predict, hence a risk that this type of dietary supplements might have some adverse impact on the immunity cannot be excluded, especially after their chronic administration.
10

Effect of KLP-602 on virus replication in cell cultures

63%
Malaczewska J., Rotkiewicz Z.
Polish Journal of Veterinary Sciences
|
2004
|
tom 07
|
nr 2
11

Laktoferyna - bialko multipotencjalne

63%
Malaczewska J., Rotkiewicz Z.
Medycyna Weterynaryjna
|
2007
|
tom 63
|
nr 02
136-139
Lactoferrin is an iron-binding protein from the transferrin family and was first isolated from milk. Lactoferrin is produced by polymorph nuclear leukocytes and epithelial cells of many mammalian species and is present in such mucosal secretions as tears, saliva, seminal and vaginal fluids as well as in several organs and blood. Many biological functions of lactoferrin have been identified: iron absorption, bacteriostatic, bactericidal, fungicidal, antiviral, antiparasitic and antitumour activities. It is also well known for its immunomodulatory and antiinflammatory properties. Additionally, lactoferrin is thought to possess protease, ribonuclease, procoagulant and transcription factor activities. Nowadays bovine lactoferrin is isolated and purified on an industrial scale and used for food preservation and production of infant formulas, yogurt, skim milk, chewing gum, cosmetic formulas, nutritional supplements and therapeutic supplements for pets. The use of lactoferrin as an immunostimulator is a promising area especially in the case of patients with immunosupression.
12

Commercial metal-based nanocolloids - evaluation of cytotoxicity

63%
Malaczewska J., Siwicki A. K.
Bulletin of the Veterinary Institute in Puławy
|
2015
|
tom 59
|
nr 1
The purpose of the study was to determine the cytotoxicity of commercial silver, gold, and copper nanocolloids towards two established cell lines (NIH/3T3 and GMK) and primar) chick embryo cell culture (CECC), using routine colorimetric assays: MTT, NRU, and LDH, which enable a preliminary evaluation of the mechanism of cytotoxic effect of the tested substances. The MTT assay evaluates the activity of mitochondria, NRU assay reveals the damage to lysosomes, while LDH assay shows injuries to the cytoplasmic membrane. The NRU assay proved to be non-applicable to the tested nanocolloids, most probably due to the interaction of nanoparticles with neutral red dye, which affected the colorimetric reaction. The MTT assay was more sensitive than LDH because the intercellular effect of a substance occurs before permanent damage to the cytoplasmic membrane. Silver nanocolloid was distinguished by the highest cytotoxicity, irrespective of the applied cell model, although the other two metals showed some cytotoxic effects as well, with gold nanocolloid being more toxic than copper one. Although the primary chick embryo cell culture, as a model reflecting more faithfully the conditions in a living organism than continuous cell lines, was undistinguished by elevated tolerance to the most toxic silver nanocolloid, it showed the tendency to recovery from the growth suppression with longer exposure after the application of less toxic gold and copper nanocolloids.
13
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The in vitro effect of commercially available noble metal nanocolloids on the rainbow trout (Oncorhynchus mykiss) leukocyte and splenocyte activity

63%
Malaczewska J., Siwicki A. K.
Polish Journal of Veterinary Sciences
|
2013
|
tom 16
|
nr 1
The growing popularity of nanotechnology in the past decade has increased nanomaterial concentrations in the environment and the risk of their toxicity for aquatic organisms. Metal nanoparticles, which are easily absorbed and accumulated by fish, are probably able to interact directly with their immunocompetent cells. The objective of this study was to evaluate the in vitro effect of commercially available silver, gold and copper nanocolloids on the rainbow trout leukocyte and splenocyte activity. At high concentrations, all of the nanocolloids studied had adverse effects on the proliferative response of trout lymphocytes, and the most toxic of them, silver, decreased also the respiratory burst activity of splenocytes. Low concentrations of silver nanocolloid, however, had a stimulating effect on the lymhocyte proliferation.
14
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Commercial metal-based nanocolloids - lack of virucidal activity against ECBO virus

63%
Malaczewska J., Siwicki A. K.
Polish Journal of Veterinary Sciences
|
2014
|
tom 17
|
nr 3
Metallic nanoparticles, mainly silver ones, have been widely used as antibacterial agents, and some studies shown they also exert direct antiviral activity against both enveloped and non-enveloped viruses. The objective of this study has been to evaluate the virucidal activity of commercial silver, gold, copper and platinum nanocolloids, recommended by the manufacturer as antimicrobials, against the ECBO virus, according to Polish Standard PN-EN 14675:2006. The highest experimentally observed decrease in the viral load was 0.875 log, which - when contrasted with the reduction in virus titre of at least 4 log expected from disinfectants - indicates that none of the analyzed nanocolloids had a disinfectant power towards the ECBO virus under the conditions defined by the standard.
15

Effect of methisoprinol and KLP-602 on virus replication in chicken embryos

63%
Malaczewska J., Rotkiewicz Z.
Polish Journal of Veterinary Sciences
|
2005
|
tom 08
|
nr 4
16

Effect of methisoprinol on virus replication in cell cultures

63%
Malaczewska J., Rotkiewicz Z.
Polish Journal of Veterinary Sciences
|
2004
|
tom 07
|
nr 2
17
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Immunomodulating effect of Inter Yeast S on the non-specific and specific cellular and humoral immunity in lambs

63%
Malaczewska J., Milewski S.
Polish Journal of Veterinary Sciences
|
2010
|
tom 13
|
nr 1
163-170
The objective of this study was to determine the stimulating effect of the Inter Yeast S dietary supplement on selected parameters of specific and non-specific humoral and cellular immunity in lambs. The study involved 32 lambs aged 30±3 days, divided into two equal groups: I - control, and II - experimental. Experimental group animals were fed a C-J concentrate mixed with a prebiotic, the Inter Yeast S, commercially available, containing dried brewer's yeast Saccharomyces cerevisiae in the amount of 3 g/kg of the concentrate. At the beginning of the experiment (day 0) and on the 15th, 30th and 60th day of the study, blood was sampled from the jugular vein to determine selected parameters of biochemical, specific and non-specific humoral and cellular immunity in lambs (total protein levels, gamma globulin levels, lysozyme activity, ceruloplasmin activity, proliferative response of blood lymphocytes (MTT) after stimulation with LPS or ConA, the metabolic activity (RBA) and potential killing activity (PKA) of phagocytes). As regards humoral immunity parameters, significantly higher gamma globulin levels and higher lysozyme and ceruloplasmin activity were found in blood serum of experimental lambs administered the Inter Yeast S, compared with those determined in control lambs not fed the supplement. No statistically significant differences in serum total protein were found between the control and experimental groups. An analysis of cellular immunity indicators revealed significantly higher levels of RBA and PKA, and higher proliferative response of blood lymphocytes (MTT) after stimulation with LPS and ConA in the experimental group, compared with those observed in the control group.
18

Biological properties of Roakin strain of NDV and TK900 strain of ADV after serial passages in CECC in the presence of Methisoprinol and KLP-602

63%
Malaczewska J., Rotkiewicz Z.
Polish Journal of Veterinary Sciences
|
2005
|
tom 08
|
nr 1
19

Laktoferyna - mechanizmy dzialania przeciwwirusowego

51%
Malaczewska J., Rotkiewicz Z., Siwicki A. K.
Medycyna Weterynaryjna
|
2006
|
tom 62
|
nr 10
1104-1107
Lactoferrin (LF) is an iron-binding protein from the transferrin family present in mucus secretions such as milk, tears, saliva, seminal and vaginal fluids and also found in several organs and blood. It is well known for having antibacterial, immunomodulatory and anti-inflammatory properties. Lactoferrin is also capable of inhibiting the replication of both DNA- and RNA-viruses. Studies indicate that LF inhibits infection of the host cell by directly binding to virus particles or by binding to target cell molecules that the virus uses as a receptor or co-receptor. Additionally, LF regulates the antiviral response of the immune system through stimulating cells which play an important role during the early phases of viral infection, e.g. natural killer cells, monocytes, macrophages and granulocytes. The use of lactoferrin as an antiviral drug has a promising future, especially in cases of patients with immunosupression.
20

Effect of beta-1,3-1,6-D-glucan on the phagocytic activity and oxidative metabolism of pripheral blood granulocytes and monocytes in rats

51%
Wojcik R., Janowska E., Malaczewska J., Siwicki A. K.
Bulletin of the Veterinary Institute in Puławy
|
2009
|
tom 53
|
nr 2
241-246
The experiment was performed on 20 adult Wistar rats aged 12 weeks, divided into two equal groups (control and experimental), each comprised of five males and five females. From the first day of the experiment, the experimental group rats were fed Murigran feed supplemented with ß-l,3/l,6-D-glucan at a dosage of 12-19 mg/rat/d, subject to body weight, while the control- group was administered the same feed without any additives. At the beginning of the experiment and then after 14 days, arterial blood samples were collected from the rats and diluted with heparin to measure and compare the phagocytic activity and oxidative metabolism of peripheral blood granulocytes and monocytes by flow cytometry. Statistically higher levels of the activity were observed in the group of rats administered glucan than in controls, expressed in terms of the percentage of phagocytic cells as well as average fluorescence intensity. ß-l,3/l,6-D-glucan also had a positive effect on the oxidative metabolism of both granulocytes and monocytes after stimulation with E. coli, and on the oxidative metabolism of granulocytes after stimulation with PMA.
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