China
Africa
Explore chapters and articles related to this topic
Chemical, Biochemical, and Medicinal Properties of the Diphosphonates
Published in Richard L. Hilderbrand, The Role of Phosphonates in Living Systems, 2018
Marion D. Francis, Raymond R. Martodam
Soft tissue calcification (calciphylaxis) can be experimentally induced by many techniques and the diphosphonates have been found to be effective at preventing calcification in most of these models. The joint ankylosis and heteretopic calcification associated with the Freund’s adjuvant model of arthritis are controlled by HEDP and Cl2MDP.131,132 These protective effects may be a result of the inhibition of bone resorption so that the local calcium and phosphorous concentrations in the soft tissues of the paw never increase to a concentration that would induce precipitation; conversely, crystal growth inhibition effects cannot be ruled out with current data. A number of diphosphonates, including Cl2MDP, HEDP, and APD, are effective at inhibiting aortic and kidney calcification in animals receiving high doses of vitamin D.32,161–163 Cl2MDP and HEDP also inhibit calciphylaxis of the skin following the administration of lead acetate or polymyxin B.164 A single oral dose of dihydrotachysterol (DHT) will induce myocardial and vascular degeneration and calcification in rats. Pretreatment or treatment after the administration of DHT with HEDP and to a lesser extent Cl2MDP inhibits the degeneration and calcification.165 Similarly, HEDP reduces the number of lesions and amount of calcified arteriosclerotic plaque induced in rabbits by a hypercholesterolemic diet in conjunction with high doses of vitamin D and nicotine.166 A model of ectopic osteoneogenesis can be developed by the implantation of devitalized bone homografts. HEDP does not affect the initial recellularization of the matrix or the concomitant rise in alkaline phosphatase activity, but does block the remodeling and mineralization process.167,168
Fab is the most efficient format to express functional antibodies by yeast surface display
Published in mAbs, 2018
Coline Sivelle, Raphaël Sierocki, Kelly Ferreira-Pinto, Stéphanie Simon, Bernard Maillere, Hervé Nozach
As variations of signal corresponding to antigen binding could be attributed either to differences of expression levels or to functional differences, dissociation constants (KD) were determined for each displayed Fab [Fig. 3]. The measured KD values for IpaD_301 and IpaD_318 are 3.2 nM and 1.7 nM, respectively. This result is in accordance with the KD evaluated by OctetRed with measured affinities of 1.1 nM and 0.9 nM (Supplementary Fig. 4). Yeast expressing anti-TNF Fabs show subnanomolar KD, 161 pM for adalimumab, 102 pM for infliximab, 39 pM for golimumab and 11 pM for certolizumab. These KD values are consistent with the reported KD determined for the corresponding IgG molecules using SPR,25 indicating that Fabs expressed on the surface of yeast cells have a very strong affinity for their antigen.
Aberrant fucosylation enables breast cancer clusterin to interact with dendritic cell-specific ICAM-grabbing non-integrin (DC-SIGN)
Published in OncoImmunology, 2019
Antonela Merlotti, Alvaro López Malizia, Paula Michea, Pierre-Emmanuel Bonte, Christel Goudot, María Sol Carregal, Nicolás Nuñez, Christine Sedlik, Ana Ceballos, Vassili Soumelis, Sebastián Amigorena, Jorge Geffner, Eliane Piaggio, Juan Sabatte
Western blot using DC-SIGN-huFc chimera (R&D 161-DC-050) was carried out as described.10 Samples were analyzed by SDS-PAGE (4–12% polyacrylamide gel under reducing conditions), transferred onto a nitrocellulose blot, treated with DC-SIGN-huFc chimera (1 µg/ml in a buffer containing 20 mM Tris, 150 mM NaCl, 1 mM CaCl2, and 2 mM MgCl2 for 4 h at 4°C), and stained with secondary antibodies. Alternatively, membranes were treated with polyclonal goat IgG anti-clusterin (R&D AF2937) and stained with secondary antibodies.
Discovery of antimicrobial compounds targeting bacterial type FAD synthetases
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2018
María Sebastián, Ernesto Anoz-Carbonell, Begoña Gracia, Pilar Cossio, José Antonio Aínsa, Isaías Lans, Milagros Medina
The interaction of CaFADS with compounds 24, 27 and 31 was characterised using ITC. This is a very powerful technique because first the shape of the thermograms informs us about the number of binding sites related to the thermodynamic nature of binding. Then, fitting of experimental data to the equations describing binding models allow determining thermodynamic binding parameters, as well as binding stoichiometry at each of the different binding sites. Thus, analysis of our ITC titrations indicates that the three compounds bind the enzyme at, at least, one binding site (Figure 5(A), Table 4). Thus, we identified in CaFADS a unique binding site of moderate-low affinity for 31 (N ≈ 1, Kd = 30.9 ± 2.8 µM) and two binding sites of high and similar affinity for 27 (N ≈ 2, Kd,av = 0.7 ± 0.07 µM, this Kd,av value is an average value, since the similarity between the two binding sites prevents them to be distinguished). These 27 and 31 binding sites are expected to be located at the enzyme FMNAT domain, since that is the inhibited activity. The interaction between the hit 24 and the enzyme resulted more complicated, because our ITC data indicate that compound 24 binds to the protein at three sites. Two of them show similar and strong affinity (Kd,av = 1.1 ± 0.1 µM) and therefore, we suggest that they might be located at the FMNAT module, since that is the activity mainly inhibited by compound 24. The third site for 24 binding has lower affinity (Kd = 161 ± 20 µM). Since this compound also mildly inhibits the RFK activity, we presume this third binding site may be at the RFK module. All bindings here characterised (with the only exception of the low affinity binding site for 24) are favoured by the enthalpic contribution (Figure 5(B), Table 4). This suggests a net gain of H-bonding and ion-pair interactions and indicates specific binding interactions. Regarding the entropic contribution to the binding free energy, it is small and favourable for 24 and 27, and only slightly unfavourable for 31 (Figure 5(B), Table 4). However, it drives the binding of 24 to the RFK module (site 3 Figure 5(B)), revealing that it might be non-specific and that could occur due to the compound hydrophobicity and rigidity37.