Investigations on blood physiology, tissues histology and gene expression profile of Fusarium oxysporum challenged fish

Labeo rohita was challenged with Fusarium oxysporum to demonstrate a thorough immune response. Significant alterations in hematological parameters viz; erythrocyte, hemoglobin, hematocrit, mean corpuscular hemoglobin concentration, mean corpuscular volume, packed cell volume, platelets, and leukocytes were observed. Total serum protein, albumin, globulin, A/G ratio, aspartate aminotransferase, alkaline aminotransferase, alkaline phosphatase activity, and cholesterol were also altered in the infected fish. Marked histopathological lesions in gills, liver, and kidney (fusion of gill lamella, necrosis, edema, vacuolization, glomerulus congestion, dilated bowman’s space and renal tubules alterations) were recorded. Tissue specific gene expression data showed that interleukin was upregulated in infected fish gills, liver, and kidney but was downregulated in blood. Tumor necrosis factor-α expression was upregulated in blood, liver, and kidney and was downregulated in gills. Upregulation of interferon-γ was observed in blood, gills, and kidney but downregulated in liver. All the cellular and molecular findings from this study can be taken as critical biomarkers in the advancement of diagnostic techniques against fungal infections as a part of wide-ranging programs of systematic and comprehensive monitoring of fish health and immune system

RNAseq Profiling of Leukocyte Populations in Zebrafish Larvae Reveals a cxcl11 Chemokine Gene as a Marker of Macrophage Polarization During Mycobacterial Infection

Macrophages are phagocytic cells from the innate immune system, which forms the first line of host defense against invading pathogens. These highly dynamic immune cells can adopt specific functional phenotypes, with the pro-inflammatory M1 and anti-inflammatory M2 polarization states as the two extremes. Recently, the process of macrophage polarization during inflammation has been visualized by real time imaging in larvae of the zebrafish. This model organism has also become widely used to study macrophage responses to microbial pathogens. To support the increasing use of zebrafish in macrophage biology, we set out to determine the complete transcriptome of zebrafish larval macrophages. We studied the specificity of the macrophage signature compared with other larval immune cells and the macrophage-specific expression changes upon infection. We made use of the well-established mpeg1, mpx, and lck fluorescent reporter lines to sort and sequence the transcriptome of larval macrophages, neutrophils, and lymphoid progenitor cells, respectively. Our results provide a complete dataset of genes expressed in these different immune cell types and highlight their similarities and differences. Major differences between the macrophage and neutrophil signatures were found within the families of proteinases. Furthermore, expression of genes involved in antigen presentation and processing was specifically detected in macrophages, while lymphoid progenitors showed expression of genes involved in macrophage activation. Comparison with datasets of in vitro polarized human macrophages revealed that zebrafish macrophages express a strongly homologous gene set, comprising both M1 and M2 markers. Furthermore, transcriptome analysis of low numbers of macrophages infected by the intracellular pathogen Mycobacterium marinum revealed that infected macrophages change their transcriptomic response by downregulation of M2-associated genes and overexpression of specific M1-associated genes. Among the infection-induced genes, a homolog of the human CXCL11 chemokine gene, cxcl11aa, stood out as the most strongly overexpressed M1 marker. Upregulation of cxcl11aa in Mycobacterium-infected macrophages was found to require the function of Myd88, a critical adaptor molecule in the Toll-like and interleukin 1 receptor pathways that are central to pathogen recognition and activation of the innate immune response. Altogether, our data provide a valuable data mining resource to support infection and inflammation research in the zebrafish model

Corrigendum: RNAseq Profiling of Leukocyte Populations in Zebrafish Larvae Reveals a cxcl11 Chemokine Gene as a Marker of Macrophage Polarization During Mycobacterial Infection.

[This corrects the article DOI: 10.3389/fimmu.2019.00832.]

Size- and Shape-Dependent Antibacterial Studies of Silver Nanoparticles Synthesized by Wet Chemical Routes

Silver nanoparticles (AgNPs) of different shapes and sizes were prepared by solution-based chemical reduction routes. Silver nitrate was used as a precursor, tri-sodium citrate (TSC) and sodium borohydride as reducing agents, while polyvinylpyrrolidone (PVP) was used as a stabilizing agent. The morphology, size, and structural properties of obtained nanoparticles were characterized by scanning electron microscopy (SEM), UV-visible spectroscopy (UV-VIS), and X-ray diffraction (XRD) techniques. Spherical AgNPs, as depicted by SEM, were found to have diameters in the range of 15 to 90 nm while lengths of the edges of the triangular particles were about 150 nm. The characteristic surface plasmon resonance (SPR) peaks of different spherical silver colloids occurring in the wavelength range of 397 to 504 nm, whereas triangular particles showed two peaks, first at 392 nm and second at 789 nm as measured by UV-VIS. The XRD spectra of the prepared samples indicated the face-centered cubic crystalline structure of metallic AgNPs. The in vitro antibacterial properties of all synthesized AgNPs against two types of Gram-negative bacteria, Pseudomonas aeruginosa and Escherichia coli were examined by Kirby–Bauer disk diffusion susceptibility method. It was noticed that the smallest-sized spherical AgNPs demonstrated a better antibacterial activity against both bacterial strains as compared to the triangular and larger spherical shaped AgNPs

Random mutagenesis to enhance the toxicity of Bacillus thuringiensisCcry proteins against Earias vittella (F.)

Insecticidal proteins derived from Bacillus thuringiensis (Bt) are widely utilized in a variety of insect control applications, including sprays and transgenic crops. The development of resistance in pests, on the other hand, can lessen the effectiveness of Bt toxins. In this study, we made efforts to enhance the toxicity of two cry proteins Cry1Ac and Cry2Aa through random mutagenesis against cotton bollworm (Earias vitella), one of the most destructive cotton pests in Pakistan. Random mutagenesis is an important tool for elucidating protein structure-function relationships and for modifying proteins to enhance or change their characteristics. We focused on whole cry proteins for random mutagenesis through error-prone PCR and constructed a recombinant library of cry proteins. Sequence analysis of eight mutants showed the mutations of 34 different nucleotides in Cry1Ac and Cry2Aa genes. All mutants were spared for toxicity bioassays against 2nd instar larvae of spotted bollworm. Cry1Ac mutant RM1AcM4 (D242E) and Cry2Aa mutants RM2AaM2 (T354A, T492R, F511L, G585E, D606Y) showed enhanced toxicity as compared to proteins without mutation. These two mutants comprise the mutations in domain-II of cry proteins important in specificity determining regions on midgut receptors in insect pests

A Comparative Assessment of Nanotoxicity Induced by Metal (Silver, Nickel) and Metal Oxide (Cobalt, Chromium) Nanoparticles in <i>Labeo rohita</i>

In the present in vivo study, we provide a comparison of toxicological consequences induced by four different types of spherical nanoparticles (NPs)&#8212;silver nanoparticles (AgNPs, 40 &#177; 6 nm), nickel (NiNPs, 43 &#177; 6 nm), cobalt oxide (Co3O4NPs, 60 &#177; 6 nm), and chromium oxide (Cr3O4NPs, 50 &#177; 5 nm)&#8212;on freshwater fish Labeo rohita. Fish were exposed to NPs (25 mg/L) for 21 days. We observed a NPs type-dependent toxicity in fish. An altered behavior showing signs of stress and a substantial reduction in total leukocyte count was noticed in all NP-treated groups. A low total erythrocyte count in all NP-treated fish except for Co3O4NPs was discerned while a low survival rate in the case of Cr3O4NP-treated fish was observed. A significant decrease in growth and hemoglobin were noticed in NiNP- and Cr3O4NP-treated fish. A considerable total protein elevation was detected in NiNP-, Co3O4NP-, and Cr3O4NP-treated groups. An upgrading in albumin level was witnessed in Co3O4NP- and Cr3O4NP-treated groups while a high level of globulin was noted in NiNP- and Co3O4NP-exposed groups. In all NP-treated groups, a depleted activity of antioxidative enzymes and pathological lesions in liver and kidney were noticed

UV-vis data

UV-vis dat

Data from: Synthesis and characterization of silver nanoparticles decorated cobalt nanocomposites (Co@AgNPs) and their density-dependent antibacterial activity

Magnetic cores loaded with metallic nanoparticles can be promising nano-carriers for successful drug delivery at infectious sites. We report fabrication, characteristic analysis and in vitro antibacterial performance of nanocomposites comprising of cobalt cores (Co-cores) functionalized with varied concentration of silver nanoparticles (AgNPs). A two-step polyol process synchronized with transmetallation reduction method was used. Co-cores were synthesized by cobalt acetate and decoration of AgNPs was carried out by silver acetate. The density of AgNPs was varied by changing the amount of silver content as 0.01 g, 0.1g and 0.2 g in the synthesis solution. Both AgNPs and Co-cores were spherical in shape having size range of 30-80 nm and 200 nm to more than one micron respectively as determined by scanning electron microscopy. The metallic nature and face centred cubic crystalline phase of prepared nanocomposites were confirmed by x-ray diffraction. Biocompatibility analysis confirmed high cell viability of MCF7 at low concentrations of tested particles. The antibacterial performance of nanocomposites (Co@AgNPs) against Escherichia coli and Bacillus subtilis was found to be AgNPs density dependent and nanocomposites with the highest AgNPs density exhibited the maximum bactericidal efficacy. We therefore, propose Co@AgNPs as effective drug-containers for various biomedical applications

VSM Data

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