Inhibition of Chemokine-Glycosaminoglycan Interactions in Donor Tissue Reduces Mouse Allograft Vasculopathy and Transplant Rejection

Binding of chemokines to glycosaminoglycans (GAGs) is classically described as initiating inflammatory cell migration and creating tissue chemokine gradients that direct local leukocyte chemotaxis into damaged or transplanted tissues. While chemokine-receptor binding has been extensively studied during allograft transplantation, effects of glycosaminoglycan (GAG) interactions with chemokines on transplant longevity are less well known. Here we examine the impact of interrupting chemokine-GAG interactions and chemokine-receptor interactions, both locally and systemically, on vascular disease in allografts.Analysis of GAG or CC chemokine receptor 2 (CCR2) deficiency were coupled with the infusion of viral chemokine modulating proteins (CMPs) in mouse aortic allograft transplants (n = 239 mice). Inflammatory cell invasion and neointimal hyperplasia were significantly reduced in N-deacetylase-N-sulfotransferase-1 (Ndst1(f/f)TekCre(+)) heparan sulfate (GAG)-deficient (Ndst1(-/-), p<0.044) and CCR2-deficient (Ccr2(-/-), p<0.04) donor transplants. Donor tissue GAG or CCR2 deficiency markedly reduced inflammation and vasculopathy, whereas recipient deficiencies did not. Treatment with three CMPs was also investigated; Poxviral M-T1 blocks CC chemokine receptor binding, M-T7 blocks C, CC, and CXC GAG binding, and herpesviral M3 binds receptor and GAG binding for all classes. M-T7 reduced intimal hyperplasia in wild type (WT) (Ccr2(+/+), p< or =0.003 and Ccr2(-/-), p</=0.027) aortic allografts, but not in Ndst1(-/-) aortic allografts (p = 0.933). M-T1 and M3 inhibited WT (Ccr2(+/+) and Ndst1(+/+), p< or =0.006) allograft vasculopathy, but did not block vasculopathy in Ccr2(-/-) (p = 0.61). M-T7 treatment alone, even without immunosuppressive drugs, also significantly prolonged survival of renal allograft transplants (p< or =0.001).Interruption of chemokine-GAG interactions, even in the absence of chemokine-receptor blockade, is a highly effective approach to reduction of allograft rejection, reducing vascular inflammation and prolonging allograft survival. Although chemokines direct both local and systemic cell migration, interruption of inherent chemokine responses in the donor tissue unexpectedly had a greater therapeutic impact on allograft vasculopathy

Transcellular communication at the immunological synapse: A vesicular traffic-mediated mutual exchange

The cell's ability to communicate with the extracellular environment, with other cells, and with itself is a crucial feature of eukaryotic organisms. In the immune system, T lymphocytes assemble a specialized structure upon contact with antigen-presenting cells bearing a peptide-major histocompatibility complex ligand, known as the immunological synapse (IS). The IS has been extensively characterized as a signaling platform essential for T-cell activation. Moreover, emerging evidence identifies the IS as a device for vesicular traffic-mediated cell-to-cell communication as well as an active release site of soluble molecules. Here, we will review recent advances in the role of vesicular trafficking in IS assembly and focused secretion of microvesicles at the synaptic area in naïve T cells and discuss the role of the IS in transcellular communication

Hydrogen bonded capsules by layer-by-layer assembly of tannic acid and poly(2-n-propyl-2-oxazoline) for encapsulation and release of macromolecules

We report hydrogen bonded capsules with the built-in ability to release loaded bioactive molecules at a physiological temperature of 37 degrees C. The use of neutral and non-toxic building blocks such as tannic acid (TA) and poly(2-n-propyl-2-oxazoline)s (PnPropOx) as hydrogen bonding donor and acceptor results in stable hollow capsules. The temperature induced morphological changes of the shell were investigated using a scanning electron microscope and an optical microscope and revealed pore formation in the shell when the temperature (T) increases beyond the cloud point temperature (T-CP) of PnPropOx. Furthermore, confocal laser scanning microscopic investigation of the hollow capsules loaded with different probes of varying hydrodynamic diameters revealed that the open and closed state of the capsules could be effectively manipulated by varying the incubation time and hydrodynamic radius of the probes. Such hydrogen bonded capsules have high potential for use in temperature responsive sustained drug delivery applications

Lysozyme microspheres incorporated with anisotropic gold nanorods for ultrasound activated drug delivery

We report on the fabrication of lysozyme microspheres (LyMs) incorporated with gold nanorods (NRs) as a distinctive approach for the encapsulation and release of an anticancer drug, 5-Fluorouracil (5-FU). LyMs with an average size of 4.0 &amp; PLUSMN; 1.0 mu m were prepared by a sonochemical method and characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR). The LyMs were examined using hydrophobic (nile red) as well as hydrophilic (trypan blue) dyes under confocal laser scanning microscopy (CLSM) to obtain information about the preferential distribution of fluorescent molecules. Notably, the fluorescent molecules were accumulated in the inner lining of LyMs as the core was occupied with air. The encapsulation efficiency of 5-FU for LyMs-NR was found to be-64%. The drug release from control LyMs as well as LyMs incorporated with NRs was investigated under the influence of ultrasound (US) at 200 kHz. The total release for control LyMs and LyMs incorporated with gold NRs was found to be-70 and 95% after 1 h, respectively. The density difference caused by NR incorporation on the shell played a key role in rupturing the LyMs-NR under US irradiation. Furthermore, 5-FU loaded LyMs-NR exhibited excellent anticancer activity against the THP-1 cell line (-90% cell death) when irradiated with US of 200 kHz. The enhanced anti-cancer activity of LyMs-NR was caused by the transfer of released 5-FU molecules from bulk to the interior of the cell via temporary pores formed on the surface of cancer cells, i.e., sonoporation. Thus, LyMs-NR demonstrated here has a high potential for use as carriers in the field of drug delivery, bio-imaging and therapy

AJWAIN SEEDS AS CAPPING AGENT FOR Bi2O3 NANOFLAKES: SYNTHESIS AND GROWTH INHIBITING EFFICIENCY OF BACTERIA

Objective: This work is mainly focused to determine the antibacterial activity of the green synthesized Bi2O3 nanoparticles against the bacterial strains, Staphylococcus aureus and Escherichia coli using resazurin as indicator. Methods: Bismuth oxide nanoparticles were synthesized from the precursor bismuth nitrate [Bi (NO3)3.5H20] by using trachyspermum ammi (ajwain) seed extract. To carry out these works, the synthesized Bi2O3 NPs undergone characterizations and were confirmed by UV-Vis, FT-IR, XRD, SEM and EDAX, TGA-DTA and DLS. Biological activity was done using a well diffusion method. Results: Bi2O3 NP's&nbsp;has been tested against bacteria (S. aureus and E. coli) in wells&nbsp;and shows blue colour, indicating bacterial growth inhibition in a dose-dependent manner for different concentrations. Conclusion: The biological studies were done with one gram-positive and one gram-negative bacteria to show the inhibiting efficiency. The synthesized bismuth oxide nanoparticles showed good anti-bacterial activity (different concentrations) against S. aureus and E. coli

Myxoma viral serpin, Serp-1, inhibits human monocyte adhesion through regulation of actin-binding protein filamin B.

Serp-1 is a secreted myxoma viral serine protease inhibitor (serpin) with proven, highly effective, anti-inflammatory defensive activity during host cell infection, as well as potent immunomodulatory activity in a wide range of animal disease models. Serp-1 binds urokinase-type plasminogen activator (uPA) and the tissue-type PA, plasmin, and factor Xa, requiring uPA receptor (uPAR) for anti-inflammatory activity. To define Serp-1-mediated effects on inflammatory cell activation, we examined the association of Serp-1 with monocytes and T cells, effects on cellular migration, and the role of uPAR-linked integrins and actin-binding proteins in Serp-1 cellular responses. Our results show that Serp-1 associates directly with activated monocytes and T lymphocytes, in part through interaction with uPAR (