Cell Adherence Research Articles

Monocyte adhesion to and transmigration through endothelium following cardiopulmonary bypass shearing is mediated by IL-8 signaling

IntroductionThe use of cardiopulmonary bypass (CPB) can induce sterile systemic inflammation that contributes to morbidity and mortality, especially in children. Patients have been found to have increased expression of cytokines and transmigration of leukocytes during and after CPB. Previous work has demonstrated that the supraphysiologic shear stresses existing during CPB are sufficient to induce proinflammatory behavior in non-adherent monocytes. The interactions between shear stimulated monocytes and vascular endothelial cells have not been well studied and have important translational implications. With these studies, we tested the hypothesis that non-physiological shear stress experienced by monocytes during CPB affects the integrity and function of the endothelial monolayer.MethodsWe have used an in vitro CPB model to study the interaction between THP-1 monocyte-like cells and human neonatal dermal microvascular endothelial cells (HNDMVECs). THP-1 cells were sheared in polyvinyl chloride (PVC) tubing at 2.1 Pa, twice of the physiological shear stress, for 2 h. ELISA, adhesion and transmigration assays, qPCR, and RNA silencing were used to assess the interactions between THP-1 cells and HNDMVECs were characterized after co-culture.ResultsWe found that sheared THP-1 cells adhered to and transmigrated through the HNDMVEC monolayer more readily than static THP-1 controls. Sheared THP-1 cells disrupted the VE-cadherin and led to the reorganization of cytoskeletal F-actin of HNDMVECs. A higher level of IL-8 was detected in the sheared THP-1 and HNDMVEC co-culture medium compared to the static THP-1 and HNDMVEC medium. Further, treating HNDMVECs with IL-8 resulted in increased adherence of non-sheared THP-1 cells, and upregulation in HNDMVECs of vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1). Finally, inhibition of HNDMVECs CXCR2/IL-8 receptor with Reparixin and of IL-8 expression with siRNA blocked sheared THP-1 cell adhesion to the endothelial monolayer.ConclusionsThese results suggest that CPB-like sheared monocytes promote IL-8 production followed by increased endothelium permeability, and monocyte adhesion and transmigration. This study revealed a novel mechanism of post-CPB inflammation and will contribute to the development of targeted therapeutics to prevent and repair the damage to neonatal patients.

Deciphering Cronobacter sakazakii pathogenicity: Exploring virulence factors and host interactions": A short review

Opportunistic human pathogen called Cronobacter spp. can cause severe illnesses in immunocompromised individuals and newborns. These species are mostly responsible for disorders like meningitis, necrotizing enterocolitis, and bacteremia because they can survive in very dry foods like PIF and have also been identified in various environmental niches, including plants. These species' contamination is ascribed to biofilms, which are biotic or abiotic surface communities. Because they build biofilms on a variety of surfaces, identifying and eliminating them is extremely difficult. For the purpose of creating efficient treatment interventions and preventative measures, it is essential to comprehend the processes of virulence and the relationship between this pathogen and its host. A variety of virulence factors, such as adhesion factors, invasion proteins, biofilm formation components, and secreted toxins, contribute to Cronobacter spp. pathogenicity. Genes involved in capsule formation—such as those involved in exopolysaccharide synthesis—are essential to its pathogenicity because they are critical in desiccation resistance and resistance to host immunological defenses. Furthermore, genes that encode flagella, fimbriae, and outer membrane proteins are linked to host cell adherence and invasion. This review also explores the emerging link between Cronobacter spp. and plants, highlighting the bacterium's ability to survive and persist in the environment because Plants may act as reservoirs, contributing to the contamination of raw agricultural products, which can subsequently enter the food supply chain. Developing focused preventative measures and treatment approaches requires knowledge of the various biological as well as genetic factors that contribute to Cronobacter spp. virulence and how it affects the host. This review clarifies the effects of Cronobacter spp. on the host and investigates the genes linked to virulence in Cronobacter.

Melt Electrowriting of Polyhydroxyalkanoates for Enzymatically Degradable Scaffolds.

Melt electrowriting (MEW) enables precise scaffold fabrication for biomedical applications. With a limited number of processable materials with short and tunable degradation times, polyhydroxyalkanoates (PHAs) present an interesting option. Here, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and a blend of PHBV and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (PHBV+P34HB) are successfully melt electrowritten into scaffolds with various architectures. PHBV+P34HB exhibits greater thermal stability, making it a superior printing material compared to PHBV in MEW. The PHBV+P34HB scaffolds subjected to enzymatic degradation show tunable degradation times, governed by enzyme dilution, incubation time, and scaffold surface area. PHBV+P34HB scaffolds seeded with human dermal fibroblasts (HDFs), demonstrate enhanced cell adherence, proliferation, and spreading. The HDFs, when exposed to the enzyme solutions and enzymatic degradation residues, show good viability and proliferation rates. Additionally, HDFs grown on enzymatically pre-incubated scaffolds do not show any difference in behavior compared those grown on control scaffolds. It is concluded that PHAs, as biobased materials with enzymatically tunable degradability rates, are an important addition to the already limited set of materials available for MEW technology.

Serologic investigation and management of an antibody screen negative para-Bombay phenotype during pregnancy

Abstract Introduction/Objective Individuals with the Bombay and para-Bombay red blood cell (RBC) phenotypes express anti- H antibodies associated with acute hemolytic transfusion reactions. The rarity of compatible donor units creates unique logistical challenges. However, para-Bombay individuals have been shown to tolerate transfusion of non- Bombay RBCs without acute hemolysis. Therefore, accurate serologic identification and judicious management of blood products are crucial when planning to transfuse patients with anti-H. This is especially true during pregnancy, as early onset of labor and fetal distress can occur without warning. Methods/Case Report A 24-year-old gravida 2 para 1 (G2P1) at approximately 38 weeks gestation with the fetus in breech position was transferred to our hospital after anti-H antibodies were detected. Although our in-house antibody screen was negative on automated solid-phase red cell adherence (SPRCA) testing, manual tube testing revealed the presence of anti-H antibodies, and forward typing with Ulex europaeus lectin confirmed the absence of H-antigen. Further, Lewis B phenotyping and saliva neutralization demonstrated the presence of H-antigen in secretions, consistent with the O-para-Bombay phenotype. Finally, differential adsorption ruled out other clinically significant allo- antibodies. An external cephalic version (ECV) was initially planned since vaginal delivery carries lower bleeding risk than cesarean section (CS). Three frozen Bombay RBC units were obtained, with one possibly compromised before arrival. Four pre-warmed, cross-match compatible units of O-positive RBCs (non-Bombay) were also prepared. Acknowledging the unpredictability of ECV, the challenge of timing thawed frozen units, and the possibilities of massive hemorrhage versus wasting rare donor blood, our transfusion service ultimately recommended an elective CS with only one Bombay unit deglycerolized. The patient underwent an uneventful procedure without transfusion. Results (if a Case Study enter NA) NA Conclusion Overall, this case highlights key diagnostic and management considerations for patients with Bombay and para-Bombay phenotypes. First, automated SPRCA testing may provide false negative results for anti-H antibodies. Second, backup transfusion strategies for para-Bombay patients may include non-Bombay RBCs. Finally, the procurement, preparation, and use of rare donor blood products requires multidisciplinary clinical decision-making to optimize patient outcomes, especially for high-risk labor when unexpected acute bleeding events can occur.

Pepgen-P15 delivery to bone: A novel 3D printed scaffold for enhanced bone regeneration

Pepgen-P15 is a combination of an organic hydroxyapatite matrix derived from bovine sources, combined with a synthetic peptide known as P-15. The interaction between α2β1 integrin and the P15 chain triggers both intracellular and extracellular signaling pathways, resulting in the production of growth factors. Three-dimensional (3D) printing has recently emerged as an innovative strategy for developing personalized therapies in bone tissue regeneration. In this research, various ratios of calcium magnesium silicate (bredigite) nanoparticles were used to modify 3D printed scaffolds made of xanthan gum and polycaprolactone (PCL) via fused deposition modeling (FDM). Scaffolds were subsequently treated with an alkaline solution, covered with graphene oxide, and finally, Pepgen-P15 was applied. the effects of xanthan gum were assessed using swellability and contact angle tests. The results indicated that, the prepared scaffolds exhibited suitable degradation rates, mechanical characteristics, and apatite formation. Alizarin red and alkaline phosphatase assays were also conducted to evaluate the scaffolds’ effectiveness in promoting bone cell differentiation during cell culture. Furthermore, the surface of the scaffold was examined to determine the amount of Pepgen-P15 loaded and released. According to the findings, the scaffold composed of 20 % bredigite and 0.3 % graphene oxide, coated with Pepgen-P15, demonstrate optimal mechanical properties, cell adherence, development, and proliferation. Typically, it is a good candidate for use in bone tissue engineering.

Advances in Electrospun Poly(ε-caprolactone)-Based Nanofibrous Scaffolds for Tissue Engineering.

Tissue engineering has great potential for the restoration of damaged tissue due to injury or disease. During tissue development, scaffolds provide structural support for cell growth. To grow healthy tissue, the principal components of such scaffolds must be biocompatible and nontoxic. Poly(ε-caprolactone) (PCL) is a biopolymer that has been used as a key component of composite scaffolds for tissue engineering applications due to its mechanical strength and biodegradability. However, PCL alone can have low cell adherence and wettability. Blends of biomaterials can be incorporated to achieve synergistic scaffold properties for tissue engineering. Electrospun PCL-based scaffolds consist of single or blended-composition nanofibers and nanofibers with multi-layered internal architectures (i.e., core-shell nanofibers or multi-layered nanofibers). Nanofiber diameter, composition, and mechanical properties, biocompatibility, and drug-loading capacity are among the tunable properties of electrospun PCL-based scaffolds. Scaffold properties including wettability, mechanical strength, and biocompatibility have been further enhanced with scaffold layering, surface modification, and coating techniques. In this article, we review nanofibrous electrospun PCL-based scaffold fabrication and the applications of PCL-based scaffolds in tissue engineering as reported in the recent literature.

Development of a Human Recombinant Collagen for Vat Polymerization-Based Bioprinting.

In light-based 3D-bioprinting, gelatin methacrylate (GelMA) is one of the most widely used materials, as it supports cell attachment, and shows good biocompatibility and degradability in vivo. However, as an animal-derived material, it also causes safety concerns when used in medical applications. Gelatin is a partial hydrolysate of collagen, containing high amounts of hydroxyproline. This causes the material to form a thermally induced gel at ambient temperatures, a behavior also observed in GelMA. This temperature-dependent gelation requires precise temperature control during the bioprinting process to prevent the gelation of the material. To avoid safety concerns associated with animal-derived materials and reduce potential issues caused by thermal gelation, a recombinant human alpha-1 collagen I fragment was expressed in Komagataella phaffii without hydroxylation. The resulting protein was successfully modified with methacryloyl groups and underwent rapid photopolymerization upon ultraviolet light exposure. The developed material exhibited slightly slower polymerization and lower storage modulus compared to GelMA, while it showed higher stretchability. However, unlike the latter, the material did not undergo physical gelation at ambient temperatures, but only when cooled down to below 10°C, a characteristic that has not been described for comparable materials so far. This gelation was not caused by the formation of triple-helical structures, as shown by the absence of the characteristic peak at 220nm in CD spectra. Moreover, the developed recombinant material facilitated cell adherence with high cell viability after crosslinking via light to a 3D structure. Furthermore, desired geometries could be easily printed on a stereolithographic bioprinter.

Unveiling the anti-giardial properties of Andrographis paniculata leaf extract through in vitro studies.

Giardiasis, caused by the parasite Giardia lamblia, is a prevalent and serious public health concern, particularly affecting children worldwide. The primary mode of transmission for the parasite is through contaminated food and water sources and often leads to the onset of diarrhoea in infected individuals. However, the present medications for Giardiasis treatment often come with numerous side effects, while the growing problem of drug resistance adds a significant complication. Therefore, there is an urgent need for alternative treatments. In this study, we explored the in-vitro potential of Andrographis paniculata leaf extract as a possible alternative treatment for Giardiasis. Our investigation involved assessing the impact of the ethanolic extract on Giardia trophozoites through the analysis of parameters such as cell death, morphological alterations, adherence, ROS generation, and cell cycle dynamics. A. paniculata leaf extracts demonstrated significant inhibitory activity against the growth of Giardia trophozoites. After being incubated for 24 hours, the test results revealed an IC50 value of 51.26µg/ml (95% CI 37.17- 65.35) for inducing cell death in Giardia trophozoites. We observed a substantial degradation of DNA, alteration in morphology, inhibition in adherence, ROS generation and inhibition of the cell cycle in Giardia trophozoites. The findings indicate that A. paniculata extract has the potential to be used as a therapeutic treatment for giardiasis. This approach aims to offer a natural therapeutic solution for giardiasis, minimizing side effects and reducing the risk of drug resistance.

Developing a multifunctional chitosan composite sponge for managing traumatic injuries

Developing porous hemostatic sponges that are both biosafe and multifunctional remains a complex challenge. Conventional hemostatic techniques often fall short in managing bleeding effectively, leading to severe critical cases such as suboptimal hemostasis, increased infection risk, and complications arising from profuse bleeding. To address these deficits, our study introduces a novel multifunctional nanocomposite sponge that synergistically incorporates chitosan (CS), cellulose (Cel), graphene oxide (GO), and silver (Ag) nanoparticles. The resulting CS/Cel/GO/Ag developed demonstrates a swelling rate exceeding 3000 %, an absorption rate of over 2100 %, and the lowest stress surpassing 20 kPa at an initial 80 % strain. In vitro analyses reveal that the CS/Cel/GO/Ag sponge has excellent cytocompatibility, non-hemolytic nature, and competence in blood cell adherence and bacterial inhibition. In vivo evaluations further demonstrate that compared to conventional hemostatic methods, the sponge substantially enhances hemostatic efficacy, as evidenced by the marked reductions in clotting times and diminished blood loss compared to conventional hemostatic methods. Specifically, the test results of the CS/Cel/GO/Ag sponge across three different models are as follows: for the rat tail amputation model, the clotting time was 99 s, while blood loss was 222 mg; for the rat liver injury model, the clotting time was 129 s. while blood loss was 812 mg; for the rat femoral artery laceration model, the clotting time was 96 s, while blood loss was 758 mg. The compelling attributes of the CS/Cel/GO/Ag sponges position them as a promising solution for the acute management of bleeding. Their excellent performance indicates they have potential role to play in trauma care.

Chungtaejeon (CTJ) inhibits adhesion and migration of VSMC through cytoskeletal remodeling pathway

IntroductionVascular remodeling is crucial for the progression of vascular disease such as atherosclerosis. We utilize the in vitro experimental model of atherosclerosis to elucidate the activity of Chungtaejeon (CTJ), a Korean fermented tea on adhesion and migration of human aortic vascular smooth muscle cells (HASMC). Materials and methodsVarious in vitro assays such as cell viability, cell adhesion, Western blot, immunofluorescence, were carried out on HASMC to explore pathway associated with cytoskeletal remodeling during the progression of atherosclerosis. ResultsIn result, CTJ significantly inhibited adhesion of HASMC as revealed by collagen assay. Similarly, CTJ inhibited the β1-integrin protein expression as well as FAK phosphorylation. Treatment of CTJ also inhibited stress fiber formation. Likewise, adherence of cells on collagen optimally increased the expression of both RhoA and Cdc42, however, treatment of CTJ dose dependently decreased their expression. The lysophosphatidic acid stimulation of HASMC rapidly increased the level of phosphorylated forms of MLC20 within 15 min, followed by an extended level of MLC20 phosphorylation. The treatment of CTJ at a dose of 50, 100 and 250 μg/ml remarkably reduced the diphosphorylated form while decreased the level of monophosphorylated form of MLC20. ConclusionsOur results suggests that, with further validation CTJ could be a promising herbal resource for prevention of atherosclerosis.

Cardioprotective action of apocynin in isoproterenol-induced cardiac damage is mediated through Nrf-2/HO-1 signaling pathway.

This investigation evaluated the therapeutic benefit of apocynin in isoproterenol (ISO)-induced cardiac damage in rats. ISO-administered male Wistar rats were treated with apocynin for 2 weeks. Blood plasma and left ventricle of heart tissues were collected and analyzed for oxidative stress-related parameters such as malondialdehyde (MDA), advanced oxidation protein product (AOPP), and nitric oxide (NO). The activities of endogenous antioxidant enzymes such as superoxide dismutase (SOD) and catalase were also measured. The gene expressions of oxidative stress-related proteins such as Nrf-2, HO-1, and HO-2 in cardiac tissues were also measured. In silico studies like molecular docking and molecular dynamics were also performed to detect how apocynin interacts with NADPH and nitric oxide synthase at the molecular level. This investigation revealed significant elevation of serum transferase enzymes and creatinine kinase-Muscle Brain (CK-MB) activities in ISO-administered rats compared to the control. Apocynin effectively normalized the serum transferases and CK-MB activities in the blood of ISO-stressed rats. Moreover, ISO-induced elevations of MDA, NO, and AOPP levels were also suppressed by apocynin treatment. Consistently, apocynin restored the reduced SOD and catalase activities in ISO-administered rats. This restoration of enzyme activity might be due to the increased expression of Nrf-2 and HO-1 and reduced expression of iNOS and TNF-α in ISO-administered rats. Histological analysis revealed that apocynin treatment ameliorated the mononuclear cell adherence and fibrosis in the cardiac tissue of ISO-administered rats. Computational studies also support the experimental findings. This study demonstrates that apocynin prevents ISO-induced cardiac injury not only by preventing inflammation but also by empowering the antioxidant defense system.

Investigating the Impact of Flavonoids on Aspergillus flavus: Insights into Cell Wall Damage and Biofilms.

Aspergillus flavus, a fungus known for producing aflatoxins, poses significant threats to agriculture and global health. Flavonoids, plant-derived compounds, inhibit A. flavus proliferation and mitigate aflatoxin production, although the precise molecular and physical mechanisms underlying these effects remain poorly understood. In this study, we investigated three flavonoids-apigenin, luteolin, and quercetin-applied to A. flavus NRRL 3357. We determined the following: (1) glycosylated luteolin led to a 10% reduction in maximum fungal growth capacity; (2) quercetin affected cell wall integrity by triggering extreme mycelial collapse, while apigenin and luteolin caused peeling of the outer layer of cell wall; (3) luteolin exhibited the highest antioxidant capacity in the environment compared to apigenin and quercetin; (4) osmotic stress assays did not reveal morphological defects; (5) flavonoids promoted cell adherence, a precursor for biofilm formation; and (6) RNA sequencing analysis revealed that flavonoids impact expression of putative cell wall and plasma membrane biosynthesis genes. Our findings suggest that the differential effects of quercetin, luteolin, and apigenin on membrane integrity and biofilm formation may be driven by their interactions with fungal cell walls. These insights may inform the development of novel antifungal additives or plant breeding strategies focusing on plant-derived compounds in crop protection.

Harnessing piperine for enhanced antimicrobial activity of carbon dot-modified cellulose fibers

Microbial infections are a global health challenge often treated with antibiotics, but their overuse can lead to antibiotic resistance. To address this, there is a need for more efficient personal protective equipment (PPE) with novel antimicrobial techniques. One such technique involves using carbon dots (CDs) to create self-disinfecting fabrics. This study focused on synthesizing phenylboronic-acid-functionalized piperine-based carbon dots (PBA-PPCDs) and boronic acid carbon dots (BACDs) as potential antimicrobial agents. The materials were successfully synthesized using a hydrothermal method and characterized using various techniques to confirm the size, charge, fluorescence properties, and inner morphology of the CDs. The CDs showed bactericidal activity against gram-positive and gram-negative bacteria, with potent inhibition in growth especially in the presence of simulated sunlight. The antibacterial properties of the CDs were tested on cellulose discs, demonstrating strong adherence and significant inhibition of bacterial cells. The cytotoxicity studies showed that these CDs, at concentrations up to 0.1 mg/mL, and the CD-modified fibers are benign to mammalian cells, emphasizing their safety for human use. Overall, the study concluded that PBA-PPCDs and BACDs are promising candidates for modifying fibers and inducing antimicrobial activity in fabrics made of cellulose fibers.Graphical

Synthetic Extracellular Matrix of Polyvinyl Alcohol Nanofibers for Three-Dimensional Cell Culture.

An ideal extracellular matrix (ECM) replacement scaffold in a three-dimensional cell (3D) culture should induce in vivo-like interactions between the ECM and cultured cells. Highly hydrophilic polyvinyl alcohol (PVA) nanofibers disintegrate upon contact with water, resulting in the loss of their fibrous morphology in cell cultures. This can be resolved by using chemical crosslinkers and post-crosslinking. A crosslinked, water-stable, porous, and optically transparent PVA nanofibrous membrane (NM) supports the 3D growth of various cell types. The binding of cells attached to the porous PVA NM is low, resulting in the aggregation of cultured cells in prolonged cultures. PVA NMs containing integrin-binding peptides of fibronectin and laminin were produced to retain the blended peptides as cell-binding substrates. These peptide-blended PVA NMs promote peptide-specific cell adherence and growth. Various cells, including epithelial cells, cultured on these PVA NMs form layers instead of cell aggregates and spheroids, and their growth patterns are similar to those of the cells cultured on an ECM-coated PVA NM. The peptide-retained PVA NMs are non-stimulatory to dendritic cells cultured on the membranes. These peptide-retaining PVA NMs can be used as an ECM replacement matrix by providing in vivo-like interactions between the matrix and cultured cells.

Copper ions-photo dual-crosslinked alginate hydrogel for angiogenesis and osteogenesis.

Early healing of bone defects is still a clinical challenge. Many bone-filling materials have been studied, among which photocrosslinked alginate has received significant attention due to its good biocompatibility and morphological plasticity. Although it has been confirmed that photocrosslinked alginate can be used as an extracellular matrix for 3D cell culture, it lacks osteogenesis-related biological functions. This study constructed a copper ions-photo dual-crosslinked alginate hydrogel scaffold by controlling the copper ion concentration. The scaffolds were shaped by photocrosslinking and then endowed with biological functions by copper ions crosslinking. According to in vitro research, the dual-crosslinked hydrogel increased the compressive strength and favored copper dose-dependent osteoblast differentiation and cell surface adherence of rat bone marrow mesenchymal stem cells and the expression of type I collagen (Col1), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), vascular endothelial growth factor (VEGF). In addition, hydrogel scaffolds were implanted into rat skull defects, and more angiogenesis and osteogenesis could be observed in in vivo studies. The above results show that the copper-photo-crosslinked hydrogel scaffold has excellent osseointegration properties and can potentially promote angiogenesis and early healing of bone defects, providing a reference solution for bone tissue engineering materials.

Assessing Microstructural, Biomechanical, and Biocompatible Properties of TiNb Alloys for Potential Use as Load-Bearing Implants.

Titanium-Niobium (TiNb) alloys are commonly employed in a number of implantable devices, yet concerns exist regarding their use in implantology owing to the biomechanical mismatch between the implant and the host tissue. Therefore, to balance the mechanical performance of the load-bearing implant with bone, TiNb alloys with differing porosities were fabricated by powder metallurgy combined with spacer material. Microstructures and phase constituents were characterized with energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The mechanical properties were tested by uniaxial compression, and the corrosion performance was determined via a potentiodynamic polarization experiment. To evaluate a highly matched potential implant with the host, biocompatibilities such as cell viability and proliferation rate, fibronectin adsorption, plasmid-DNA interaction, and an SEM micrograph showing the cell morphology were examined in detail. The results showed that the alloys displayed open and closed pores with a uniform pore size and distribution, which allowed for cell adherence and other cellular activities. The alloys with low porosity displayed compressive strength between 618 MPa and 1295 MPa, while the alloys with high porosity showed significantly lower strength, ranging from 48 MPa to 331 MPa. The biological evaluation of the alloys demonstrated good cell attachment and proliferation rates.

Antioxidant, antibacterial, and anti-biofilm activities of selected indigenous plant species against nosocomial bacterial pathogens.

Biofilms are responsible for over 60% of nosocomial infections. The focus of this study was to investigate the antioxidant, antibacterial, antibiofilm, and anti-motility activities of Gardenia volkensii, Carissa bispinosa, Peltophorum africanum, and Senna petersiana. Antioxidant activity was evaluated using free radical (DPPH) scavenging and ferric reducing power assays. Antibacterial and antibiofilm activities were evaluated using the broth micro-dilution and the crystal violet assays, respectively. Anti-motility was evaluated using anti-swarming activities, and the brine shrimp lethality assay was used for cytotoxicity. Gardenia volkensii and C. bispinosa acetone extracts had low EC50 values of 9.59 and 9.99μg ml-1on the free-radical scavenging activity, respectively. All the plant extracts demonstrated broad-spectrum antibacterial activity against Klebsiella pneumoniae, Pseudomonasa aeruginosa, Escherichia coli, Enterococcus faecalis, and Staphylococcus aureus [minimum inhibitory concentration (MIC)<0.63mg ml-1]. The initial cell adherence stage of P. aeruginosa and E. coli was the most susceptible stage where sub-MICs resulted in inhibitions>50%. Peltophorum africanum had the least cytotoxic effects. All extracts had anti-motility activity against P. aeruginosa and E. coli. This study showed that not only do the plants have strong antibacterial activity but had noteworthy inhibition (>50%) of initial cell adherence and may be suitable candidates for the treatment of nosocomial pathogens.

Adaptation of Rhizobium leguminosarum sv. trifolii strains to low temperature stress in both free-living stage and during symbiosis with clover

Legume-rhizobial symbiosis plays an important role in agriculture and ecological restoration. This process occurs within special new structures, called nodules, formed mainly on legume roots. Soil bacteria, commonly known as rhizobia, fix atmospheric dinitrogen, converting it into a form that can be assimilated by plants. Various environmental factors, including a low temperature, have an impact on the symbiotic efficiency. Nevertheless, the effect of temperature on the phenotypic and symbiotic traits of rhizobia has not been determined in detail to date. Therefore, in this study, the influence of temperature on different cell surface and symbiotic properties of rhizobia was estimated. In total, 31 Rhizobium leguminosarum sv. trifolii strains isolated from root nodules of red clover plants growing in the subpolar and temperate climate regions, which essentially differ in year and day temperature profiles, were chosen for this analysis. Our results showed that temperature has a significant effect on several surface properties of rhizobial cells, such as hydrophobicity, aggregation, and motility. Low temperature also stimulated EPS synthesis and biofilm formation in R. leguminosarum sv. trifolii. This extracellular polysaccharide is known to play an important protective role against different environmental stresses. The strains produced large amounts of EPS under tested temperature conditions that facilitated adherence of rhizobial cells to different surfaces. The high adaptability of these strains to cold stress was also confirmed during symbiosis. Irrespective of their climatic origin, the strains proved to be highly effective in attachment to legume roots and were efficient microsymbionts of clover plants. However, some diversity in the response to low temperature stress was found among the strains. Among them, M16 and R137 proved to be highly competitive and efficient in nodule occupancy and biomass production; thus, they can be potential yield-enhancing inoculants of legumes.

3D Culture Analysis of Cancer Cell Adherence to Ex Vivo Lung Microexplants.

Ex vivo 3D culture of human tissue explants addresses many limitations of traditional monolayer cell culture techniques, namely the lack of cellular heterogeneity and absence of 3D intercellular spatial relationships, but presents challenges with regard to repeatability owing to the difficulty of acquiring multiple tissue samples from the same donor. In this study, we used a cryopreserved bank of human lung microexplants, ∼1 mm3 fragments of peripheral lung from donors undergoing lung resection surgery, and a liquid-like solid 3D culture matrix to describe a method for the analysis of non-small-cell lung cancer adhesion to human lung tissue. H226 (squamous cell carcinoma), H441 (lung adenocarcinoma), and H460 (large cell carcinoma) cell lines were cocultured with lung microexplants. Confocal fluorescence microscopy was used to visualize the adherence of each cell line to lung microexplants. Adherent cancer cells were quantified following filtration of nonadherent cells, digestion of cultured microexplants, and flow cytometry. This method was used to evaluate the role of integrins in cancer cell adherence. A statistically significant decrease in the adherence of H460 cells to lung microexplants was observed when anti-integrins were administered to H460 cells before coculture with lung microexplants.

Secretome from iPSC-derived MSCs exerts proangiogenic and immunosuppressive effects to alleviate radiation-induced vascular endothelial cell damage

BackgroundRadiation therapy is the standard of care for central nervous system tumours. Despite the success of radiation therapy in reducing tumour mass, irradiation (IR)-induced vasculopathies and neuroinflammation contribute to late-delayed complications, neurodegeneration, and premature ageing in long-term cancer survivors. Mesenchymal stromal cells (MSCs) are adult stem cells that facilitate tissue integrity, homeostasis, and repair. Here, we investigated the potential of the iPSC-derived MSC (iMSC) secretome in immunomodulation and vasculature repair in response to radiation injury utilizing human cell lines.MethodsWe generated iPSC-derived iMSC lines and evaluated the potential of their conditioned media (iMSC CM) to treat IR-induced injuries in human monocytes (THP1) and brain vascular endothelial cells (hCMEC/D3). We further assessed factors in the iMSC secretome, their modulation, and the molecular pathways they elicit.ResultsIncreasing doses of IR disturbed endothelial tube and spheroid formation in hCMEC/D3. When IR-injured hCMEC/D3 (IR ≤ 5 Gy) were treated with iMSC CM, endothelial cell viability, adherence, spheroid compactness, and proangiogenic sprout formation were significantly ameliorated, and IR-induced ROS levels were reduced. iMSC CM augmented tube formation in cocultures of hCMEC/D3 and iMSCs. Consistently, iMSC CM facilitated angiogenesis in a zebrafish model in vivo. Furthermore, iMSC CM suppressed IR-induced NFκB activation, TNF-α release, and ROS production in THP1 cells. Additionally, iMSC CM diminished NF-kB activation in THP1 cells cocultured with irradiated hCMEC/D3, iMSCs, or HMC3 microglial lines. The cytokine array revealed that iMSC CM contains the proangiogenic and immunosuppressive factors MCP1/CCL2, IL6, IL8/CXCL8, ANG (Angiogenin), GROα/CXCL1, and RANTES/CCL5. Common promoter regulatory elements were enriched in TF-binding motifs such as androgen receptor (ANDR) and GATA2. hCMEC/D3 phosphokinome profiling revealed increased expression of pro-survival factors, the PI3K/AKT/mTOR modulator PRAS40 and β-catenin in response to CM. The transcriptome analysis revealed increased expression of GATA2 in iMSCs and the enrichment of pathways involved in RNA metabolism, translation, mitochondrial respiration, DNA damage repair, and neurodevelopment.ConclusionsThe iMSC secretome is a comodulated composite of proangiogenic and immunosuppressive factors that has the potential to alleviate radiation-induced vascular endothelial cell damage and immune activation.