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Current in vivo Models for Brain Disorders
Published in Carla Vitorino, Andreia Jorge, Alberto Pais, Nanoparticles for Brain Drug Delivery, 2021
Marta Guerra-Rebollo, Cristina Garrido
Nanotechnology has also offered the first rays of hope in the treatment for neuroAIDS, which until the date has no effective vaccines or specific drug therapy. Dou et al. have developed a macrophage-based NP platform for antiretroviral drug delivery [36]. They designed a novel bone marrow-derived macrophage (BMM) pharmacologic NP delivery system. Hypothesising that the system will improve drug distribution to areas of active viral replication, and extend dosing intervals and this way achieving therapeutic efficacy. Their model was based on loading indinavir (antiretroviral drug) nanosuspension into BMMs (NP-IDV-BMMs) and administered intravenously into naive mice or NOD/SCID mice humanised with human peripheral blood lymphocytes reconstitution infected with human immunodeficiency virus 1 (HIV-1). Cell tissue distribution was tracked by single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) of radio- and superparamagnetic iron oxide (SPIO; Feridex)-labelled BMMs, and confirmed by histology. Antiretroviral therapeutic responses and immune response were studied in humanised infected mice.
Antiprotozoal Effects of Wild Plants
Published in Mahendra Rai, Shandesh Bhattarai, Chistiane M. Feitosa, Ethnopharmacology of Wild Plants, 2021
Muhammad Subbayyal Akram, Rao Zahid Abbas, José L. Martinez
Pentalinon andrieuxii (Figure 7.7) belongs to family Apocynaceae and is natively found in the forests of Mexico. In Mayan Folk medication, it’s used for the treatment of lesions related to cutaneous leishmaniasis (Pan et al. 2012). The aqueous and organic extraction methods are used to get extracts from its leaves and roots. Its extract contains numerous secondary metabolites, including triterpenoids, cardenolides, flavonoids, trinorsesquiterpenoids and pregnane sterols (Lezama-Davila et al. 2007). Phytochemical analysis reveals the presence of one triterpenoid, three coumarins, and 16 sterol derivatives. Five sterols proved to be more active and have higher inhibit effects than the Sodium stibogluconate (it’s a drug which is referred for leishmania treatment) after 48-hours of exposure with IC50 of 1.4 to 3.5 μM and 2.7 μM, respectively. Among these derivatives, 6,7-dihydroneridienone and cholest-4-en-3-one are the most active metabolites with IC50 values of 9.2 μM and 0.03 μM. These compounds were also proven to be non-cytotoxic to bone marrow-derived macrophages. These compounds halt biosynthesis of sterol, which causes an alteration in the membrane of Leishmania spp. and results in destruction and abnormalities of amastigotes morphology (Pan et al. 2012).
Genetic Control of Endotoxin Responsiveness: The Lps Gene Revisited
Published in Helmut Brade, Steven M. Opal, Stefanie N. Vogel, David C. Morrison, Endotoxin in Health and Disease, 2020
Stefanie N. Vogel, Nayantara Bhat, Danielle Malo, Salman T. Qureshi
A novel strategy for isolating the Lps gene was developed, based upon acquisition of LPS responsiveness in C3H/HeJ macrophages after transfection with cDNA clones from C3H/HeN (.Lpsn) macrophages (C. R. Maliszewski, M. Schoenborn, and S. N. Vogel, unpublished observations). Transfected C3H/HeJ macrophages were plated in chamber slides, cultured for 2 days, and then LPS-stimulated. A cDNA clone conferring LPS sensitivity (i.e., complementing the Lpsd defect) should permit the C3H/HeJ macrophages to respond to LPS by producing TNF-α. To detect TNF-α-producing cells, slide chambers were incubated with 125I-anti-murine TNF-α monoclonal antibody, washed, and then dipped in photographic emulsion. After 3 days in the dark, slides were developed, fixed, and scanned microscopically for the rare cell laden with dark grains. This method was verified through various means, including demonstration that a single Lpsn macrophage could be detected against a background of 1000 Lpsd macrophages. A highly enriched cDNA library generated from C3H/HeN (.Lpsn) macrophage mRNA in the pDC303 plasmid (a mammalian expression vector that contains a CMV-based promoter cassette) was screened using this method. This vector had been used successfully to express specific genes in transfected bone marrow–derived macrophages. Unfortunately, screening 500,000 cDNA clones (from pools of 500 clones) in transfected rGM-CSF–derived C3H/HeJ bone marrow macrophages failed to yield any convincingly positive clones.
The ancestral stringent response potentiator, DksA has been adapted throughout Salmonella evolution to orchestrate the expression of metabolic, motility, and virulence pathways
Published in Gut Microbes, 2022
Helit Cohen, Boaz Adani, Emiliano Cohen, Bar Piscon, Shalhevet Azriel, Prerak Desai, Heike Bähre, Michael McClelland, Galia Rahav, Ohad Gal-Mor
These results suggested that since DksA is involved in the regulation of at least a few SPI-2 genes, it may contribute to the intracellular survival of Salmonella. To test this possibility, the uptake and survival of the studied three species and their dksA mutant strains were used to infect bone marrow-derived macrophages (BMDMs). The uptake of both S. Typhimurium and S. bongori dksA mutants was reduced relative to their WT strains (Figure 6(c)), probably due to the contribution of T3SS-1 to Salmonella entry, even into phagocytic cells. In addition, a S. Typhimurium dksA mutant strain was significantly impaired in intracellular survival compared to the WT background (Figure 6(d)). These results are in agreement with a previous report by Henard and colleagues33 and indicate that DksA is required for intracellular survival of S. enterica in macrophages, at least partly, due to its role in SPI-2 regulation. Noteworthy, the intracellular survival of S. bongori and E. coli in BMDM was very low to begin with (since they don’t carry the SPI-2), however the lack of DksA in these species, even further reduced their viability to an undetected level. These results suggest additional intracellular role for DksA, which is SPI-2-independent, such as its previously reported role in S. Typhimurium tolerance to reactive oxygen and nitrogen species.33–35
The commensal bacterium Lactiplantibacillus plantarum imprints innate memory-like responses in mononuclear phagocytes
Published in Gut Microbes, 2021
Aize Pellon, Diego Barriales, Ainize Peña-Cearra, Janire Castelo-Careaga, Ainhoa Palacios, Nerea Lopez, Estibaliz Atondo, Miguel Angel Pascual-Itoiz, Itziar Martín-Ruiz, Leticia Sampedro, Monika Gonzalez-Lopez, Laura Bárcena, Teresa Martín-Mateos, Jose María Landete, Rafael Prados-Rosales, Laura Plaza-Vinuesa, Rosario Muñoz, Blanca de las Rivas, Juan Miguel Rodríguez, Edurne Berra, Ana M. Aransay, Leticia Abecia, Jose Luis Lavín, Hector Rodríguez, Juan Anguita
In order to validate our results, we used two primary cellular models, murine bone marrow-derived macrophages (mBMM) and human monocyte-derived macrophages (hMDM). Overall, intracellular survival of L. plantarum strains was observed in both cell types, although to a lesser extent in comparison with the RAW264.7 cell line (Figure 1a, b). Similar to our observations using the cell line, intracellular survival of L. casei was lower than that of L. plantarum strains, with the presence of viable E. coli within the macrophages being dramatically decreased from the beginning of the experiment. Similar results were observed when an m.o.i. of 1 was used (Fig. S1C, D). To detect the cellular compartment in which L. plantarum persists inside macrophages, we incubated mBMMs with mCherry-labeled bacteria and assessed their colocalization with LAMP-2, a phagolysosome marker 17, using confocal microscopy. Notably, while heat-killed bacteria were observed surrounded by LAMP-2 positive vesicles, live bacteria did not show colocalization with the marker suggesting that they are able to evade their localization within these degradative organelles (Figure 1c).
IL-6 augments IL-4-induced polarization of primary human macrophages through synergy of STAT3, STAT6 and BATF transcription factors
Published in OncoImmunology, 2018
Sahil Gupta, Arpit Jain, Shahzad Nawaz Syed, Ryan G. Snodgrass, Beatrice Pflüger-Müller, Matthias S. Leisegang, Andreas Weigert, Ralf P. Brandes, Ingo Ebersberger, Bernhard Brüne, Dmitry Namgaladze
How combinations of cytokines and other soluble factors of the tumor microenvironment shape the TAM phenotype is poorly understood. Investigating different cytokine polarization patterns gives insights into designing effective therapies to reprogram TAMs towards anti-tumor phenotypes.30 Recently, a study investigating the synergistic effects of IL-4 and IL-6 to promote TAMs pro-invasive properties was reported in murine bone marrow-derived macrophages (BMDMs).31 Another example of cytokine interactions depicted an antagonism of IFNγ-stimulated transcriptional response by IL-4.32 However, the mechanism how IL-6 maintains its dichotomous role in shaping the phenotype of human macrophages is unclear. In this study, we address the mechanistic and functional aspects of how IL-6 interacts with IL-4 to polarize primary human monocyte derived macrophages (hMDMs) and explore co-regulated target genes.