Imunomodulatorna aktivnost rekombinanatne izoforme lektina iz banane u fiziološkim i patološkim uslovima u debelom crevu miševa BALB/c soja

Banana lectin (BanLec) is primarily isolated from the fruit of banana (Musa paradisiac). It is glucose / mannose-specific lectin that belongs to the jackalin superfamily of lectins. There are several naturally occurring BanLec isoforms. Nowadays BanLec can also be produced by recombinant technology (rBanLec). rBanLec possesses structural and functional characteristics that highly resemble those reported for its natural counterparts. As most plant lectins, (r)BanLec is resistant to denaturation/proteolytic cleavage in the gastrointestinal tract. It has been reported that rBanLec attaches specifically to the mucosal surface of small intestine and passes into subepithelial compartment. (r)BanLec has been recognized as a potential immunomodulator. It has been shown that (r)BanLec modulates functional characteristics of lymphocytes but the effects of (r)BanLec stimulation in other immune cells are not yet elucidated. The aim of this study was to investigate immunomodulatory / immunostimulatory activity of rBanLec in the colon of BALB/c mice. This aim was accomplished through evaluation of the impact of rBanLec stimulation on 1) functional characteristics of antigen presenting cells (APC) isolated from BALB/c mice 2) local immune system in the large intestine of healthy BALB/c mice, and 3) the course of TNBS-induced experimental colitis in BALB/c mice. Peritoneal macrophages and spleen dendritic cells (DC) isolated from BALB/c mice were used in vitro for the evaluation of rBanLec influence on functional characteristics of APC. Generally, it is shown that rBanLec in a dose-dependent manner modulated the functional characteristics of APCs. By using resident (RMs) and thioglycollate-elicited (TGMs) peritoneal macrophages, it has been shown that effects of rBanLec stimulation depend on its concentration but also on the functional status of macrophages. Obtained results have clearly shown that rBanLec, in a positive dosedependent manner, promotes pro-inflammatory phenotype with BALB/c RMs (enhancement of NO and IL-12, reduction of arginase activity and IL-4 secretion) while, in the same manner, it tends to skew BALB/c TGMs towards anti-inflammatory profile (reduction of NO and IL-12 production, enhancement of arginase activity and IL-4 secretion). The dose-dependent changes in production of TGF-β by peritoneal macrophages also depended on their functional status: rBanLec stimulated the production of TGF-β by RMs in a negative dose-dependent manner, while in TGMs production of TGF-β positively correlated to the rBanLec concentration. The activity of myeloperoxidase (MPO) and productions of TNF-α and IL-10 were enhanced upon rBanLec stimulation in a positive dose-dependent manner with both RMs and TGMs. Further, it was shown that interactions of rBanLec with TLR2 and TLR4 / CD14 are important for initiations of the production of pro-inflammatory mediators by peritoneal macrophages irrespective to their functional status. rBanLec also stimulated in a specific dose-dependent manner the secretion of effector cytokines IFN-γ and IL-4 (negative dose dependent manner) and regulatory cytokine IL-10 (positive dose-dependent manner) by spleen DCs...Lektin banane (BanLec) pripada podgrupi lektina koji vezuju glukozu ili manoza- u okviru familije lektina sličnih žakalinu. U plodu banane, koji predstavlja prirodni izvor BanLec-a, javlja se u više izoformi, a može se proizvesti i rekombinantnom DNK tehnologijom. Rekombinantna izoforma BanLec-a (rBanLec) je po svojim strukturnim karakteristikama i specifičnosti vrlo slična prirodnim izoformama. Kao i većina biljnih lektina, (r)BanLec ne podleže brzo denaturaciji / razgradnji u uslovima digestivnog trakta, a pokazano je da se vezuje za epitel tankog creva i postepeno prolazi u subepitelni prostor. Danas je poznato da BanLec, nezavisno od izoforme, ima imunomodulatorni potencijal. Dosadašnja istraživanja su se dominantno bavila uticajem (r)BanLec-a na funkcionalne karakteristike limfocita i pokazano je da stimulacije određene ćelijske populacije prirodnim i rekombinantnom izoformom kvalitativno imaju isti ishod. Uticaj (r)BanLec-a na funkcionalne karakteristike drugih ćelija imunskog sistema nije detaljno analiziran. Cilj ove doktorske teze je da se kroz ispitivanja (1) modulatornog dejstva rBanLeca na funkcionalne karakteristike antigen-prezentujućih ćelija (APĆ) BALB/c miša, (2) imunomodulatornog dejstva rBanLec-a u debelom crevu BALB/c miša u fiziološkim uslovima, i (3) efekata profilaktičke i terapijske primene rBanLec-a u modelu TNBS-om indukovanog kolitisa kod BALB/c miša, dobije uvid u imunomodulatorni efekat rBanLec-a na imunski sistem u mukozi debelog creva miševa BALB/c soja pod specifičnim uslovima. Koristeći peritonealne makrofage i dendritske ćelije slezine (DĆ) kao in vitro model sisteme, pokazano je da rBanLec dozno-zavisno moduliše funkcionalne karakteristike APĆ BALB/c miševa. Analiza uticaja rBanLec stimulacije na karakteristike rezidentnih (RM) i tioglikolatom-indukovanh (TGM) peritonealnh makrofaga, pokazala je da ishod stimulacije određene ćelijske populacije nije jednoznačan već zavisi od njihovog funkcionalnog stanja. rBanLec na pozitivan dozno-zavisan način pospešuje proinflamatorni kapacitet RM (povećanje produkcije NO i IL-12 i smanjenje aktivnosti arginaze i sekrecije IL-4), a na isti način smanjuje proinflamatorni kapacitet TGM (smanjenje produkcije NO i IL-12 i povećanje aktivnosti arginaze i sekrecije IL-4). Uticaj rBanLec-a na produkciju TGF-β kod peritonealnih makrofaga takođe zavisi od funkcionalnog stanja makrofaga (kod RM, rBanLec negativno dozno-zavisan, a kod TGM pozitivno dozno-zavisno utiče na produkciju TGF-β). I kod RM i kod TGM, rBanLec na pozitivan dozno-zavisan način podstiče aktivnost mijeloperoksidaze (MPO), produkciju TNF-α i IL-10. Za stimulaciju produkcije proinflamatornih medijatora, nezavisno od funkcionalnog stanja makrofaga, značajno je vezivanje rBanLec-a za TLR2 i TLR4 / CD14. rBanLec utiče na sekreciju efektorskih citokina IFN-γ i IL-4 (negativno dozno-zavisno) i regulatornog citokina IL-10 (pozitivno dozno-zavisno) od strane DĆ slezine. rBanLec TLR2-posredovana stimulacija DĆ slezine nije ključna za promene u ekspresiji Ifn-γ i Il-4..

Immunomodulatory activity of recombinant banana lectin isoform in large intestine of BALB/c mice under physiological and pathological conditions

Lektin banane (BanLec) pripada podgrupi lektina koji vezuju glukozu ili manoza- u okviru familije lektina sličnih žakalinu. U plodu banane, koji predstavlja prirodni izvor BanLec-a, javlja se u više izoformi, a može se proizvesti i rekombinantnom DNK tehnologijom. Rekombinantna izoforma BanLec-a (rBanLec) je po svojim strukturnim karakteristikama i specifičnosti vrlo slična prirodnim izoformama. Kao i većina biljnih lektina, (r)BanLec ne podleže brzo denaturaciji / razgradnji u uslovima digestivnog trakta, a pokazano je da se vezuje za epitel tankog creva i postepeno prolazi u subepitelni prostor. Danas je poznato da BanLec, nezavisno od izoforme, ima imunomodulatorni potencijal. Dosadašnja istraživanja su se dominantno bavila uticajem (r)BanLec-a na funkcionalne karakteristike limfocita i pokazano je da stimulacije određene ćelijske populacije prirodnim i rekombinantnom izoformom kvalitativno imaju isti ishod. Uticaj (r)BanLec-a na funkcionalne karakteristike drugih ćelija imunskog sistema nije detaljno analiziran. Cilj ove doktorske teze je da se kroz ispitivanja (1) modulatornog dejstva rBanLeca na funkcionalne karakteristike antigen-prezentujućih ćelija (APĆ) BALB/c miša, (2) imunomodulatornog dejstva rBanLec-a u debelom crevu BALB/c miša u fiziološkim uslovima, i (3) efekata profilaktičke i terapijske primene rBanLec-a u modelu TNBS-om indukovanog kolitisa kod BALB/c miša, dobije uvid u imunomodulatorni efekat rBanLec-a na imunski sistem u mukozi debelog creva miševa BALB/c soja pod specifičnim uslovima. Koristeći peritonealne makrofage i dendritske ćelije slezine (DĆ) kao in vitro model sisteme, pokazano je da rBanLec dozno-zavisno moduliše funkcionalne karakteristike APĆ BALB/c miševa. Analiza uticaja rBanLec stimulacije na karakteristike rezidentnih (RM) i tioglikolatom-indukovanh (TGM) peritonealnh makrofaga, pokazala je da ishod stimulacije određene ćelijske populacije nije jednoznačan već zavisi od njihovog funkcionalnog stanja. rBanLec na pozitivan dozno-zavisan način pospešuje proinflamatorni kapacitet RM (povećanje produkcije NO i IL-12 i smanjenje aktivnosti arginaze i sekrecije IL-4), a na isti način smanjuje proinflamatorni kapacitet TGM (smanjenje produkcije NO i IL-12 i povećanje aktivnosti arginaze i sekrecije IL-4). Uticaj rBanLec-a na produkciju TGF-β kod peritonealnih makrofaga takođe zavisi od funkcionalnog stanja makrofaga (kod RM, rBanLec negativno dozno-zavisan, a kod TGM pozitivno dozno-zavisno utiče na produkciju TGF-β). I kod RM i kod TGM, rBanLec na pozitivan dozno-zavisan način podstiče aktivnost mijeloperoksidaze (MPO), produkciju TNF-α i IL-10. Za stimulaciju produkcije proinflamatornih medijatora, nezavisno od funkcionalnog stanja makrofaga, značajno je vezivanje rBanLec-a za TLR2 i TLR4 / CD14. rBanLec utiče na sekreciju efektorskih citokina IFN-γ i IL-4 (negativno dozno-zavisno) i regulatornog citokina IL-10 (pozitivno dozno-zavisno) od strane DĆ slezine. rBanLec TLR2-posredovana stimulacija DĆ slezine nije ključna za promene u ekspresiji Ifn-γ i Il-4...Banana lectin (BanLec) is primarily isolated from the fruit of banana (Musa paradisiac). It is glucose / mannose-specific lectin that belongs to the jackalin superfamily of lectins. There are several naturally occurring BanLec isoforms. Nowadays BanLec can also be produced by recombinant technology (rBanLec). rBanLec possesses structural and functional characteristics that highly resemble those reported for its natural counterparts. As most plant lectins, (r)BanLec is resistant to denaturation/proteolytic cleavage in the gastrointestinal tract. It has been reported that rBanLec attaches specifically to the mucosal surface of small intestine and passes into subepithelial compartment. (r)BanLec has been recognized as a potential immunomodulator. It has been shown that (r)BanLec modulates functional characteristics of lymphocytes but the effects of (r)BanLec stimulation in other immune cells are not yet elucidated. The aim of this study was to investigate immunomodulatory / immunostimulatory activity of rBanLec in the colon of BALB/c mice. This aim was accomplished through evaluation of the impact of rBanLec stimulation on 1) functional characteristics of antigen presenting cells (APC) isolated from BALB/c mice 2) local immune system in the large intestine of healthy BALB/c mice, and 3) the course of TNBS-induced experimental colitis in BALB/c mice. Peritoneal macrophages and spleen dendritic cells (DC) isolated from BALB/c mice were used in vitro for the evaluation of rBanLec influence on functional characteristics of APC. Generally, it is shown that rBanLec in a dose-dependent manner modulated the functional characteristics of APCs. By using resident (RMs) and thioglycollate-elicited (TGMs) peritoneal macrophages, it has been shown that effects of rBanLec stimulation depend on its concentration but also on the functional status of macrophages. Obtained results have clearly shown that rBanLec, in a positive dosedependent manner, promotes pro-inflammatory phenotype with BALB/c RMs (enhancement of NO and IL-12, reduction of arginase activity and IL-4 secretion) while, in the same manner, it tends to skew BALB/c TGMs towards anti-inflammatory profile (reduction of NO and IL-12 production, enhancement of arginase activity and IL-4 secretion). The dose-dependent changes in production of TGF-β by peritoneal macrophages also depended on their functional status: rBanLec stimulated the production of TGF-β by RMs in a negative dose-dependent manner, while in TGMs production of TGF-β positively correlated to the rBanLec concentration. The activity of myeloperoxidase (MPO) and productions of TNF-α and IL-10 were enhanced upon rBanLec stimulation in a positive dose-dependent manner with both RMs and TGMs. Further, it was shown that interactions of rBanLec with TLR2 and TLR4 / CD14 are important for initiations of the production of pro-inflammatory mediators by peritoneal macrophages irrespective to their functional status. rBanLec also stimulated in a specific dose-dependent manner the secretion of effector cytokines IFN-γ and IL-4 (negative dose dependent manner) and regulatory cytokine IL-10 (positive dose-dependent manner) by spleen DCs..

LEAD – A PREANALYTICAL/ANALYTICAL VARIABLE IN CLINICAL CHEMISTRY

Lead is one of the most studied clinically important metals due its high toxicity and a high number of workers exposed to it. The interest toward Pb is elevated by the fact that children are especially susceptible to lead poisoning. Research regarding lead poisoning requires a complex, multi-disciplinary (clinical medical and clinical chemical) approach. Monitoring human exposure to lead (intake, i.e. poisoning) may be achieved by quantification of Pb in tissues and body fluids. For that reason, a number of accurate and reliable analytical methods for the determination of Pb (analytical/preanalytical variable) were developed. An objective of this review paper is to provide key information necessary for proper interpretation of results of lead related clinical/laboratory tests. OLOVO - PREANALITIČKA/ANALITIČKA VARIJABLA U KLINIČKOJ HEMIJI Olovo spada u red najizučavanijih klinički relevantnih metala zbog svoje toksičnosti i broja radnika izloženih ovom metalu. Povećano interesovanje prema ovom metalu je posledica i toga što su deca naročito podložna trovanju njime. Ispitivanja koja se tiču trovanja olovom zahtevaju kompleksan, multidisciplinaran (kliničko-medicinski i kliničko-hemijski) pristup. Monitoring izlaganja olovu (unos, odnosno trovanje) se može ostvariti kvantifikacijom Pb u tkivima i telesnim tečnostima. Iz tog razloga je razvijen veliki broj preciznih i pouzdanih metoda za njegovo određivanje (analitička/preanalitička varijabla). Cilj ovog preglednog članka je da sumira ključne informacije neophodne za valjanu interpretaciju rezultata kliničkih/laboratorijskih testova vezanih za olovo

Antiproliferative and antimigratory effects of 3-(4-substituted benzyl)-5-isopropyl-5-phenylhydantoin derivatives in human breast cancer cells

In this study, a series of synthesized 3-(4-substituted benzyl)-5-isopropyl-5-phenylhydantoin derivatives as a potential antiproliferative and antimigratory agents were investigated. The possible antitumor mechanisms of investigated hydantoin derivatives were examined on human breast cancer cell line MDA-MB-231. The cells were treated with different concentrations of compounds (from 0.01 mu M to 100 mu M) during 24 h and 72 h. The proliferation index, nitric oxide production, apoptosis rate, and migration capacity were measured. The cell invasion potential was examined by measuring the level of MMP-9 and COX-2 gene expression. All tested compounds expressed antiproliferative activity and induced dose- and time-dependent increase in the level of nitrites. The investigated molecules significantly decreased cell survival rate, migration capacity and the expression levels of genes included in the process of tumor invasion. Obtained data suggest that the tested hydantoin derivatives express considerable antitumor activity by reducing cell division rate, elevating apoptosis level, and inhibiting the motility and invasiveness of breast cancer cells. The results obtained in this study indicate that investigated compounds express potential as a novel chemotherapeutic agents against breast cancer growth and progression. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of King Saud University

Effects of iota-carrageenan on ocular Chlamydia trachomatis infection in vitro and in vivo

Ocular chlamydial infections with the ocular serovars A, B, Ba, and C of Chlamydia trachomatis represent the world's leading cause of infectious blindness. Carrageenans are naturally occurring, sulfated polysaccharides generally considered safe for food and topical applications. Carrageenans can inhibit infection caused by a variety of viruses and bacteria. To investigate whether iota-carrageenan (I-C) isolated from the red alga Chondrus crispus could prevent ocular chlamydial infection, we assessed if targeted treatment of the conjunctival mucosa with I-C affects chlamydial attachment, entry, and replication in the host cell. Immortalized human conjunctival epithelial cells were treated with I-C prior to C. trachomatis infection and analyzed by flow cytometry and immunofluorescence microscopy. In vivo effects were evaluated in an ocular guinea pig inclusion conjunctivitis model. Ocular pathology was graded daily, and chlamydial clearance was investigated. Our study showed that I-C reduces the infectivity of C. trachomatis in vitro. In vivo results showed a slight reduced ocular pathology and significantly less shedding of infectious elementary bodies by infected animals. Our results indicate that I-C could be a promising agent to reduce the transmission of ocular chlamydial infection and opens perspectives to develop prophylactic approaches to block C. trachomatis entry into the host cell

Different immobilization methods of soybean hull peroxidase on macroporous glycidyl methacrylate copolymers

Wastewater treatment is a current and important environmental issue. Phenolic compounds most of which are toxic and many even carcinogens, found in various polluted waters are non-biodegradable and present a serious health hazard. Enzymatic treatment, using peroxidase and H2O2, provides a highly selective and efficient alternative to current phenol removal methods, with low energy requirements and minimal environmental impact. Soybean hull peroxidase (SHP) isolated from soybean hulls, which are inexpensive agricultural waste products, offers a cheap source of crude enzyme available for various applications. In this study we used macroporous glycidyl methacrylate based copolymers with various surface characteristics and mean pore size diameter ranging from 40-200 nm as carriers and compared two different immobilization methods for SHP – glutaraldehyde and periodate. Our results demonstrate that SHP immobilization with both methods is influenced by the pore size of the carrier matrix with both the specific activity of the immobilized enzyme and immobilization yeald increased with pore size. Glutaraldehyde immobilization method proved to be substantially better than periodate with the highest specific activities obtained 22.8 U/g and 3.4 U/g of carrier respectively. Thermal stability at 85°C and stability in 80% dioxane solution indicate a stabilization of the immobilized enzyme compared to the free form. Although having the same pH optimum, immobilized enzyme operates over a broader pH range. Obtained biocatalyst shows an increased specific activity, higher thermal and organic solvent stability and operates over wider pH range and it’s suitable for wastewater treatment

Cross-Reactive Effects of Vaccines: Heterologous Immunity between Tetanus and Chlamydia

Vaccines can have heterologous effects on the immune system, i.e., effects other than triggering an immune response against the disease targeted by the vaccine. We investigated whether monoclonal antibodies (mAbs) specific for tetanus could cross-react with Chlamydia and confer heterologous protection against chlamydial infection. The capability of two tetanus-specific mAbs, namely mAb26 and mAb51, to prevent chlamydial infection has been assessed: (i) in vitro, by performing a neutralization assay using human conjunctival epithelial (HCjE) cells infected with Chlamydia trachomatis serovar B, and (ii) in vivo, by using a guinea pig model of Chlamydia caviae-induced inclusion conjunctivitis. The mAb26 has been superior in comparison with mAb51 in the prevention of chlamydial infection in HCjE cells. The mAb26 has conferred approximate to 40% inhibition of the infection, compared to less than 5% inhibition in the presence of the mAb51. In vivo, mAb26 significantly diminished ocular pathology intensity in guinea pigs infected with C. caviae compared to either the mAb51-treated or sham-treated guinea pigs. Our data provide insights that tetanus immunization generates antibodies which induce heterologous chlamydial immunity and promote protection beyond the intended target pathogen

Supplementary data for the article: Spasojević, D.; Zmejkoski, D.; Glamočlija, J.; Nikolić, M.; Soković, M.; Milošević, V.; Jarić, I.; Stojanović, M.; Marinković, E.; Barisani-Asenbauer, T.; et al. Lignin Model Compound in Alginate Hydrogel: A Strong Antimicrobial Agent with High Potential in Wound Treatment. International Journal of Antimicrobial Agents 2016, 48 (6), 732–735. https://doi.org/10.1016/j.ijantimicag.2016.08.014

Supplementary material for: [https://doi.org/10.1016/j.ijantimicag.2016.08.014]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2364

Modulation of functional characteristics of murine peritoneal macrophages by dehydrogenate polymer from coniferyl alcohol and alginate

The dehydrogenate polymer from coniferyl alcohol (DHP; a lignin model compound) in alginate hydrogel (ALG) has been shown to exert a strong antibacterial activity. To broadens a spectrum of potential DHP/ALG application, we aimed this study to evaluate the immunomodulatory activity of DHP/ALG. DHP and ALG were tested separately and in mixture (1:2 w/w) for their impact on in vitro production of cytokines (IL-6, IL-12, and IL-10) and reactive oxygen (ROS) and nitrogen (RNS) species by resident (RMs) and thioglycolate-elicited (TGMs) peritoneal macrophages of BALB/c mice. RMs and TGMs were stimulated (48h) with ALG and DHP in concentrations previously shown to be non-cytotoxic (up to 50 and 25 μg/ml, respectively). DHP/ALG promotes simultaneous production of inflammatory (IL-6, IL-12) and regulatory cytokines by RMs in a positive dose-dependent manner. Production of inflammatory cytokines was stimulated by ALG, while an increase in IL-10 production positively correlated to the concentration of DHP. ALG also stimulated the production of IL-12 by TGMs, which was mirrored in the outcome of ALG/DHP stimulation. The significant increase in the activity of myeloperoxidase (MPO) due to DHP and/or ALG stimulation was recorded in TGMs, while a slight increase in MPO activity in RMs was recorded only upon stimulation with the higher amount of ALG. ALG in a positive dose-dependent manner stimulated the production of ROS and RNS by both RMS and TGMs. In all cases, except ROS production by RMs, the impact of ALG stimulation was mirrored in the outcome of ALG/DHP stimulation. Our results suggest that DHP/ALG exerts an immunomodulatory activity that could complement already reported antimicrobial activity and warrants further investigation on the use of DHP/ALG in the treatment of infectious diseases