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An affinity protocol was developed for the preparation of the main serine proteinase from Deinagkistrodon acutus venom on industrial scales. As affinity ligand, l-arginine was composed to medium and its structure was confirmed by ESI-MS analysis. The purification process consisted of one major affinity chromatography step to remove more than 95% of other proteins, and a polishing step of DEAE ion-exchange chromatography for removal of minor contaminants. The serine proteinase was 100% pure analyzed on HPLC Vydac C4 column, 99.4% on TSK G3000SW column, and 97.7% with SDS-PAGE analysis. The yield of the main serine proteinase was 3.6% of crude venom protein, the recoveries of typical fibrinogen (Fg) clotting activity and arginine esterase activity of serine proteinase were 82.2% and 84%, higher than those of other reported traditional protocols, the proteinase also showed arginine amidase activity. Reducing SDS-PAGE analysis showed that the arginine esterase was a single polypeptide with the mass of approximately 40 kDa, while MALDI-TOF-TOF-MS analysis showed that the purified proteinase should be a approximately 34 kDa glycoprotein. The desorption constant Kd and the theoretical maximum absorption Qmax on the affinity medium were 9.93 x 10(-5) and 38.1mg/g medium in absorption analysis.

Preparation of molecularly imprinted polymer microspheres (MIPMs) for chloramphenicol (CAP) by aqueous suspension polymerization is reported for the first time in this study. The resulting MIPMs had the ability to specifically adsorb CAP, and the molecularly imprinted solid phase extraction (MISPE) based on the MIPMs was shown to be applicable for clean-up and preconcentration of trace CAP in milk and shrimp samples with high recoveries of 92.7% and 84.9%, respectively. Combined with MISPE, the conventional HPLC-UV analysis sensitivity for CAP in foods could be significantly increased.

Evidence suggests that doxycycline (Dox), acting through an anti-inflammatory mechanism, inhibits expression of matrix metalloproteinases (MMPs). Since the endometrial environment in contraceptive users experiencing breakthrough bleeding is characterized by elevated production of MMPs, we examined the effect of Dox on endometrial expression of MMPs using an in vitro model consisting of endometrial glandular epithelial cells (GEC), stromal (ESC) cells, and an endometrial surface epithelial cell line (HES). GEC, ESC and HES maintained under defined culture conditions expressed variable levels of MMP-2 and MMP-9, and Dox in a dose-dependent manner (1–50μg/ml) reduced the production of proMMP-2 after 24h treatment ( P −8 M), as well as TNF-α (25ng/ml) in cell- and time-dependent manners, moderately altered the expression of MMP-2 and MMP-9 mRNA in GEC, ESC and HES compared to untreated controls ( P P

Nuclease protection assay (NPA) probes were designed to target the rRNA of Chaetoceros curvisetus and Skeletonema costatum, and quantitative sandwich hybridization integrated with nuclease protection assay (NPA-SH) was developed to detect C. curvisetus and S. costatum in culture and field samples in Jiaozhou Bay, China. The specificity and validity of the NPA-SH technique were tested with cultured pure strains, mixed strains and field samples, and by comparison with that of microscopy observation. The linear detection range for C. curvisetus was 4.2 × 104 to 1.2 × 106 cells with a detection limit of 42 cells ml−1. The linear range for S. costatum was 6.0 × 104 to 1.0 × 106 cells with a detection limit of 60 cells ml−1. The NPA-SH in this study provides a convenient tool for rapid assessment of HAB species in marine environments.

Background Increased production of pro-inflammatory mediators is considered central in the manifestation of events leading to irregular uterine bleeding in progestin-only contraceptive users. Evidence suggests that in addition to its antimicrobial property, doxycycline (Dox) acts as an anti-inflammatory agent mainly through the suppression of pro-inflammatory mediators. Methods We tested this hypothesis in the endometrial environment using an in vitro model consisting of isolated human endometrial glandular epithelial and stromal cells and a human endometrial surface (HES) epithelial cell line cultured under defined conditions. Results We found that Dox at doses ranging from 1 to 100 microg/ml had a limited growth-inhibitory effect on these cells, whereas Dox in a dose-dependent manner inhibited the production of tumour necrosis factor-alpha (TNF-alpha). Using multiplex cytokine/chemokine protein analysis to test a broader range of Dox activity, we found that Dox at 25 microg/ml either alone or in the presence of 17beta-estradiol (E2), medroxyprogesterone acetate (MPA) and E2+MPA (10(-8) M) as well as TNF-alpha (25 ng/ml), representing the endometrial environment exposed to contraceptives as well as inflammatory conditions, respectively, altered the production of multiple cytokines and chemokines as compared with untreated controls. These actions of Dox occurred in cell-, ovarian steroid- and cytokine/chemokine-dependent manners. Although Dox reduced the regulatory action of steroids on the production of these cytokines/chemokines, it was less effective on TNF-alpha-treated cells. Conclusions The results support the hypothesis that Dox, by modulating the endometrial expression of multiple inflammatory-related cytokines/chemokines in a cell- and cytokine/chemokine-dependent manner, may have a therapeutic potential in patients experiencing irregular uterine bleeding, in particular in progestin-dominant contraceptive users.

A novel assay method using nuclease protection assay integrated with sandwich hybridization (NPA-SH) for qualitative and quantitative detection of microalgae has been developed. Two species-specific nuclease-protection-assay (NPA) probes targeted 28S ribosomal RNA of Prorocentrum minimum and Prorocentrum micans , respectively, were designed in this study. The assay consists of S1 nuclease protection, sandwich hybridization and signal detection. The specificity of the probes was verified with cultured algae in the laboratory and field sample from Jiaozhou Bay, and the quantity by NPA-SH analysis showed good agreement with that of cell-counting with a light microscope. The optical absorbance of probe binding on the target showed good linear fit with cell amount. A standard curve for P. minimum was established to correlate the optical absorbance to cell density on a basis in the linear range between 15 and 475 cells ml −1 seawater, and the equation deducted was ‘ y = 0.0053 × x + 0.0658’ ( R 2 = 0.992, n = 4). The assay was sensitive to detect 15 cells ml −1 seawater. And for P. micans , with linear range between 0.6 and 20 cells ml −1 seawater, the equation deducted was ‘ y = 0.1174 × x + 0.1106’ ( R 2 = 0.996, n = 4); the assay was sensitive to detect less than 1 cell ml −1 seawater. The inter-assay coefficients of variation (CVs) were 12.4 and 10.9%, respectively. The good specificity, sensitivity and reproducibility of the NPA-SH implied that this new technique could be extremely useful for qualitative and quantitative assay of P. minimum and P. micans at low abundance.

Polyclonal antibodies were raised against Gymnodinium sp. by immunizing rabbits with cells of the axenic strain. Based on the species-specific antiserum, an indirect competitive enzyme-linked immunosorbent assay (cELISA) was developed to identify and quantify Gymnodinium sp. A standard curve was established to correlate the cELISA signal to cell amount on a logit-log basis in the linear range between 24 and 6,250,000 cells, and the equation deducted was ln[ A /( A 0 − A )]= 4.9193 − 1.1006 log[cell amount] ( R 2 = 0.9948, n = 5). The detection limit was found to be 12 cells. The intra-assay and inter-assay coefficients of variation (CVs) were 5.8% and 9.7%, respectively. Field samples collected from Jiaozhou Bay, China were used to assess the robustness of the method. The results showed high agreement with that of cell-counting with a light microscope. The good reproducibility and precision of the cELISA implied that this new technique could be used for fast quantification of Gymnodinium sp.

98 Background: Bispecific antibodies (bsAbs) for redirecting T cells to cancers have shown promise in both preclinical and clinical studies. However, clinical results have been disappointing in solid cancers. We have applied the DOCK-AND-LOCK method to generate a novel class of trivalent bsAbs, each comprising an anti-CD3 scFv covalently conjugated to a stabilized dimer of different anti-tumor Fabs. Herein we report the characterization of two such constructs, (E1)-3s and (14)-3s, which activate T cells and target Trop-2- and CEACAM5-expressing cancer cells, respectively. Methods: Human breast and colonic cancer cell lines were grown in monolayer cultures or as 3D spheroids for in vitro evaluation. NOD/SCID mice carrying xenografts of MDA-MB-231 (a TNBC line constitutively expressing Trop-2 and PD-L1) were used for in vivo studies. A human PD-1 antagonistic murine hybridoma antibody was subsequently converted to its chimeric form (IMMU-cPD-1). Human PBMCs, or T cells isolated from buffy coats by negative selection, were used as effector cells in cytotoxicity assays. The effect of IMMU-cPD-1 on cancer cells pretreated with IFN-γ to induce the expression of PD-L1 was compared with those not pretreated. Results: (E1)-3s and (14)-3s, in the presence of human T cells, killed target cells grown as monolayers at low picomolar concentrations, with similar potency observed for drug-resistant cells. The antitumor efficacy was demonstrated for (E1)-3s plus human PBMCs in NOD/SCID mice bearing MDA-MB-231, and for human PBMCs combined with (E1)-3s or (14)-3s in 3D spheroids generated from target cell lines to mimic the in vivo behavior and microenvironment of these tumors. Moreover, with the addition of IMMU-cPD-1, the benefit of PD-1 blockade was indicated by increased cell death in 3D spheroids and longer survival of MDA-MB-231-bearing mice. Conclusions: These results highlight the potency of (E1)-3s and (14)-3s as T-cell redirecting bsAbs, emphasize the potential of combining such bsAbs with immune checkpoint inhibitors to improve the therapeutic activity in the immunotherapy of solid cancers, and provide a basis for using 3D spheroids as an alternative to in vivo models for evaluating T-cell functions.

The conversion of biomass to biofuels begins with biomass pretreatment. Most traditional pretreatment methods are chemical or physical. Each method has a specific effect on cellulose, hemicellulose, and lignin fractions. The main goal of pretreatment is to remove or weaken the tight linkages among cell wall components, thus increasing enzyme accessibility and improving the hydrolysis of cellulose. In recent studies, the use of the extrusion process has been described as a new, potentially viable development in the pretreatment of lignocellulosic materials and the hydrolysis of cellulose. The hypothesis is that extruder screw speed and barrel temperature may disturb biomass structure, thereby increasing accessibility of cellulose for hydrolysis. This manuscript aims to provide an overview of the major representative progress and development on the use of the extrusion process for biomass pretreatment and cellulose hydrolysis. Extrusion can be used as a physical pretreatment method in biofuel production.

We constructed novel HIV-1 fusion inhibitors that may overcome the current limitations of enfuvirtide, the first such therapeutic in this class. The three prototypes generated by the Dock-and-Lock (DNL) technology to comprise four copies of enfuvirtide tethered site-specifically to the Fc end of different humanized monoclonal antibodies potently neutralize primary isolates (both R5-tropic and X4-tropic), as well as T-cell-adapted strains of HIV-1 in vitro. All three prototypes show EC(50) values in the subnanomolar range, which are 10- to 100-fold lower than enfuvirtide and attainable whether or not the constitutive antibody targets HIV-1. The potential of such conjugates to purge latently infected cells was also demonstrated in a cell-to-cell viral inhibition assay by measuring their efficacy to inhibit the spread of HIV-1(LAI) from infected human peripheral blood mononuclear cells to Jurkat T cells over a period of 30 days following viral activation with 100 nM SAHA (suberoylanilide hydroxamic acid). The IgG-like half-life was not significantly different from that of the parental antibody, as shown by the mean serum concentration of one prototype in mice at 72 h. These encouraging results provide a rationale to develop further novel anti-HIV agents by coupling additional antibodies of interest with alternative HIV-inhibitors via recombinantly-produced, self-assembling, modules.

The systematic study of all proteins, referred to as proteomics, is performed to identify the components of a particular proteome and analyze global changes in protein expression in response to different stimuli. Over the past two decades, mass spectrometry has become an important tool for the analysis of proteins (Aebersold and Mann, 2003; Yates, 2004). It is estimated that a cell contains at least 10 000-30 000 different proteins that span a wide range of sizes, relative abundance, acidity/basicity, and hydrophobicity (Badock et al., 2001). As is known, the low-abundance and high-abundance proteins differ in concentration over nine orders of magnitude (Omenn, 2004), which results in the high-abundance proteins impeding the investigation of middleor low-abundance proteins. The separation of the protein mixture into organelles or other multi-protein complex fractions prior to a proteomics analysis is usually the first step to increase the probability of detecting low-copy-number proteins (Rabilloud et al., 1998; Taylor et al., 2000; Cronshaw et al., 2002; Jiang et al., 2004; Gao et al., 2005). Efficient and highly resolving separation of the protein mixture into organelles or other multi-protein complex fractions prior to a mass spectrometry analysis is usually used as reducing the complexity of samples, which highly increases the probability of detecting low-copy-number proteins (Rabilloud et al., 1998; Taylor et al., 2000; Cronshaw et al., 2002; Jiang et al., 2004; Gao et al., 2005). Before the widespread use of shotgun methods, proteins were fractionated by 2D gel electrophoresis (2D-gel), a method that separates them according to pI and molecular weight (Harry et al., 2000; Gygi, et al., 2000; Motoyama & Yates, 2008). Although 2D-gel has excellent resolving power for intact proteins, the process is difficult to automate, laborious, and suffers from low throughput (Klose & Kobalz, 1995). The more fundamental drawbacks are the limited dynamic range and the exclusion of certain classes, such as low-abundance proteins (Gygi et al., 2000), integral membrane proteins (Braun et al., 2007), and proteins with extremes in isoelectric point (pI) and molecular weight (MW) (Corthals et al., 2000; Oh-Ishi et al., 2000). Another explored proteins pre-fractionation methods is multidimensional liquid chromatography technique combined ion-exchange chromatography and/or hydrophobic chromatography and/or reverse-phase chromatography, which has been a powerful

Rhizoctonia solani Kuhn is the pathogen that causes sheath blight and results in significant yield reduction in rice and in nearly 50 other crops. In order to develop a new fungicide effective against this pathogen, a series of structurally diverse phenazine-1-carboxylic acid derivatives, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i, 2j, and 2k, were designed, synthesized and evaluated for their antifungal activity. The two most active compounds 2i and 2j were selected as lead compounds for further antifungal research.

Amino acids are cleanly monobenzylated at ambient temperature using benzyl chloride in water containing potassium carbonate.

Background Amino acid sequence alignment of phage phiC31 integrase with the serine recombinases family revealed highly conserved regions outside the catalytic domain. Until now, no system mutational or biochemical studies have been carried out to assess the roles of these conserved residues in the recombinaton of phiC31 integrase. Methodology/Principal Findings To determine the functional roles of these conserved residues, a series of conserved residues were targeted by site-directed mutagenesis. Out of the 17 mutants, 11 mutants showed impaired or no recombination ability, as analyzed by recombination assay both in vivo and in vitro. Results of DNA binding activity assays showed that mutants (R18A, I141A, L143A,E153A, I432A and V571A) exhibited a great decrease in DNA binding affinity, and mutants (G182A/F183A, C374A, C376A/G377A, Y393A and V566A) had completely lost their ability to bind to the specific target DNA attB as compared with wild-type protein. Further analysis of mutants (R18A, I141A, L143A and E153A) synapse and cleavage showed that these mutants were blocked in recombination at the stage of strand cleavage. Conclusions/Significance This data reveals that some of the highly conserved residues both in the N-terminus and C-terminus region of phiC31 integrase, play vital roles in the substrate binding and cleavage. The cysteine-rich motif and the C-tail val-rich region of phiC31 integrase may represent the major DNA binding domains of phiC31 integrase.

Efficient and high resolution separation of the protein mixture prior to trypsin digestion and mass spectrometry (MS) analysis is generally used to reduce the complexity of samples, an approach that highly increases the probability of detecting low-copy-number proteins. Our laboratory has constructed an affinity ligand library composed of thousands of ligands with different protein absorbance effects. Structural differences between these ligands result in different non-bonded protein–ligand interactions, thus each ligand exhibits a specific affinity to some protein groups. In this work, we first selected out several synthetic affinity ligands showing large band distribution differences in proteins absorbance profiles, and a tandem composition of these affinity ligands was used to distribute complex rat liver cytosol into simple subgroups. Ultimately, all the fractions collected from tandem affinity pre-fractionation were digested and then analyzed by LC-MS/MS, which resulted in high confidence identification of 665 unique rat protein groups, 1.8 times as many proteins as were detected in the un-fractionated sample (371 protein groups). Of these, 375 new proteins were identified in tandem fractions, and most of the proteins identified in un-fractionated sample (290, 80%) also emerged in tandem fractions. Most importantly, 430 unique proteins (64.7%) only characterized in specific fractions, indicating that the crude tissue extract was well distributed by tandem affinity fractionation. All detected proteins were bioinformatically annotated according to their physicochemical characteristics (such as MW, pI, GRAVY value, TM Helices). This approach highlighted the sensitivity of this method to a wide variety of protein classes. Combined usage of tandem affinity pre-fractionation with MS-based proteomic analysis is simple, low-cost, and effective, providing the prospect of broad application in proteomics. Copyright © 2009 John Wiley & Sons, Ltd.

This is the first report that combines cascade biomimetic affinity fractionation with MS-based proteomics analysis. Our lab has constructed an affinity ligand library composed of thousands of ligands with different protein-binding properties. Structural differences between these ligands result in different non-bonded protein–ligand interactions, thus each ligand exhibits a specific affinity to some protein groups. In this work, we first screened out three affinity ligands with large difference in protein-binding properties. Next, cascade combination of these ligands was applied to fractionate tissue sample into simple subgroups prior to trypsin digestion and LC–MS/MS analysis. In this study, 391 non-redundant protein groups were identified in unfractionated rat liver cytosol, 499 protein groups were identified in 2 fractions of the first affinity fractionation, 616 in 4 fractions of the second fractionation, and 738 in 8 fractions of the third fractionation (an 88.74% increase). Ultimately, a total of 859 unique protein groups were identified in all cascade fractions (a 119.6% increase compared with unfractionated sample). The proteins detected in each fraction were bioinformatically categorized according to their physicochemical characteristics (relative molecular mass, pI, GRAVY value and TM helices). This approach highlighted the sensitivity of this method to a wide variety of protein classes.

Overexpression of Bcl-X(L), an antiapoptotic Bcl-2 family member, occurs in a majority of head and neck squamous cell carcinomas (HNSCCs) and correlates with chemotherapy resistance in this disease. Overexpression of Bcl-2 is also observed in HNSCC, albeit less frequently. We have previously shown that peptides derived from the BH3 domains of proapoptotic proteins can be used to target Bcl-X(L) and Bcl-2 in HNSCC cells, promoting apoptosis. In this report, we examined the impact of ABT-737 (for structure, see Nature 435: 677-681, 2005 ), a potent small-molecule inhibitor of Bcl-X(L) and Bcl-2, on HNSCC cells. As a single agent, ABT-737 was largely ineffective at promoting HNSCC cell death. By contrast, ABT-737 strongly synergized with the chemotherapy drugs cisplatin and etoposide to promote HNSCC cell death and loss of clonogenic survival. Synergism between ABT-737 and chemotherapy was associated with synergistic activation of caspase-3 and cleavage of poly(ADP-ribose) polymerase. Treatment with ABT-737 plus chemotherapy resulted in dramatic up-regulation of proapoptotic Noxa protein, and small interfering RNA (siRNA)-mediated inhibition of Noxa up-regulation partially attenuated cell death by the synergistic combination. Treatment with cisplatin or etoposide, alone or in combination with ABT-737, resulted in substantial down-regulation of Mcl-1L, a known inhibitor of ABT-737 action. Further down-regulation of Mcl-1L using siRNA failed to enhance killing by the cisplatin/ABT-737 synergistic combination, indicating that chemotherapy treatment of HNSCC cells is sufficient to remove this impediment to ABT-737. Together, our results demonstrate potent synergy between ABT-737 and chemotherapy drugs in the killing of HNSCC cells and reveal an important role for Noxa in mediating synergism by these agents.

In order to foreknow poorly performing cultures before wasting energy to scale them to large cultures, industrial microbial fermentation can greatly benefit from knowledge of the physiological state of cells. The method currently proposed is an easily automated physiological state determination method. We have designed one universal rRNA-specific probe for bacteria and developed novel signal probe hybridization (SPH) assay featuring no RNA extraction and no PCR amplification steps necessary to quantify the physiological state of microbial cells. The microbial cell was lysed with sonication and SDS. Signal probes were applied to hybridize and protect the rRNA target. S1 nuclease was then applied to remove the excessive signal probes, the single-stranded RNA and the mismatch RNA/DNA hybrids. The remaining signal probe was captured with a corresponding capture probe immobilized on a microplate and quantified with a horseradish peroxidase-conjugated color reaction. We then systemically optimized our assay. Results showed that the cell limit of detection (LOD) and the cell limit of quantification (LOQ) were 2.64 × 104 cells and 9.86 × 104 cells per well of microplate, respectively. The limit of detection (LOD) and the limit of quantification (LOQ) of signal probe were 49.0 fM and 344.0 fM respectively. Using this technique, we quantified the 16S rRNA levels during the fermentation process of Pseudomonas sp. M18. Our results indicate that the 16S rRNA levels can directly inform us about the physiological state of microbial cells. This technique has great potential for application to the microbial fermentation industry.

Cobra venom is a very precious natural resource. The traditional method for purification of cardiotoxin from cobra venom is a multi-step, high cost, and low recovery procedure. By molecular modeling and docking with SYBYL software, we designed and synthesized an affinity ligand, m-aminobenzoic acid, for high efficiency purification of this therapeutically useful Chinese cobra venom cardiotoxin. The one-step recovery of cardiotoxin reached 64% and the purity reached 92% upon purification. The binding capacity of this synthetic ligand was 9.1 mg cardiotoxin/g moist weight gel and the affinity constant for cardiotoxin was 5.5 × 103 M−1. Unlike a natural affinity ligand, this synthetic ligand is highly stable, and has great potential for industrial scale production of cardiotoxin. In addition, we examined the effects of cardiotoxin on the nervous system in a mouse model. Results showed that cardiotoxin could maintain analgesic effects for 120 min with a dose of less than 0.06 mg/kg (2.8% of the LD50). Administration of 0.12 mg/kg cardiotoxin could improve scopolamine impairments of memory in mice. These results suggest that cardiotoxin may be a potential drug for nervous system diseases. Copyright © 2008 John Wiley & Sons, Ltd.

Chicken IgY (egg yolk immunoglobulin) is a functional equivalent of mammalian IgG. Traditional methods for IgY purification involve multi-step procedures that result in low recovery of IgY. After a large scale screening of our 700-member synthetic ligand library synthesized by epichlorohydrin and cyanuric chloride methods, a high efficiency ligand of IgY was found. By one-step purification with this ligand, the purity of IgY could reach 92.1%, and the recovery of IgY could reach 78.2%. This synthetic ligand had a higher binding capacity of 74.8 mg IgY/ml and had no negative effects on immunoreactivity. Remarkably, this ligand was also highly stable and could resist 1 M NaOH, thus having great potential for the industrial-scale production of IgY.

Ricin A-chain can inactivate eukaryotic ribosomes, but exhibits no N-glycosidase activity on intact E. coli ribosomes. In the present research, in order to avoid using radiolabeled oligoribonucleotides, two kinds of synthetic 5'-FAM fluorescence-labeled oligoribonucleotide substrates were used to mimic the sarcin/ricin domains of rat 28S rRNA and E. coli 23S rRNA (32mer and 25mer, named as Rat FAM-SRD and E. coli FAM-SRD, respectively). Ricin A-chain was able to specifically release adenine from the first adenosine of the GAGA tetraloop and exhibited specific N-glycosidase activity under neutral and weak acidic conditions with both substrates. However, under more acidic conditions, ricin A-chain was able to release purines from other sites on eukaryotic substrates, but it retained specific depurination activity on prokaryotic substrates. At pH 5.0, the Michaelis constant (K(m)) for the reaction with Rat FAM-SRD (4.57+/-0.28microM) corresponded to that with E. coli FAM-SRD (4.64+/-0.26microM). However, the maximum velocity (V(max)) for ricin A-chain with Rat FAM-SRD was 0.5+/-0.024microM/min, which is higher than that with E. coli FAM-SRD (0.32+/-0.011microM/min).

Specific molecularly imprinted polymers (MIPs) for the drug reserpine (RES) using methacrylic acid (MAA) as the functional monomer were developed and characterised for the first time in this study. Evaluation of the various polymers by binding assays indicated that the optimum ratio of functional monomer to template was 4:1. Furthermore, the imprinting effect of the MIPs was assessed by the chromatographic method, which demonstrated that the MIPs had better chromatographic behavior and selectivity than those of the corresponding NIPs. A combination of BET, NMR, UV spectroscopy, and MISPE analyses for investigation of the imprinting and recognition properties revealed that strong specific interactions between the functional monomer and RES in the prepolymerization solutions and the aqueous solutions were probably responsible for RES recognition. The preparation of RES MIPs and elucidation of imprinting and recognition mechanisms may serve as useful references for other drug MIPs.

A major mechanism of monoclonal antibodies that selectively target the insulin-like growth factor type 1 receptor (IGF-1R) to inhibit tumor growth is by downregulating the receptor, regardless whether they are capable (antagonistic) or incapable (agonistic) of blocking the binding of cognate ligands. We have developed and characterized a novel agonistic anti-IGF-1R humanized antibody, hR1, and used the Dock-and-Lock (DNL) method to construct Hex-hR1, the first multivalent antibody comprising 6 functional Fabs of hR1, with the aim of enhancing potency of hR1. Based on cross-blocking experiments, hR1 recognizes a region of cysteine-rich domain on the α-subunit, different from the epitopes mapped for existing anti-IGF-1R antibodies, yet hR1 is similar to other anti-IGF-1R antibodies in downregulating IGF-1R and inhibiting proliferation, colony formation, or invasion of selected cancer cell lines in vitro, as well as suppressing growth of the RH-30 rhabdomyosarcoma xenograft in nude mice when combined with the mTOR inhibitor, rapamycin. Hex-hR1 and hR1 are generally comparable in their bioactivities under the in-intro and in-vivo conditions investigated. Nevertheless, in selective experiments involving a direct comparison of potency, Hex-hR1 demonstrated a stronger effect on inhibiting cell proliferation stimulated by IGF-1 and could effectively downregulate IGF-1R at a concentration as low as 20 pM.

In this study, a fluorescence-based method was used to characterize the amino loading density on the flat surface of glass tubes functionalized by silylation with (3-aminopropyl)trimethoxysilane and then fluorescence-labeled with fluorescein isothiocyanate. The immobilized fluorescent molecules on the surface of the glass tubes were released by treatment with hydrofluoric acid. The fluorescence of the released solution was detected by a multifunction micro-plate reader, and the concentration of the fluorescent molecules was calculated from a calibration curve based on the reference compound 2a. A density calculation formula D = 27.95Y/S was developed, where Y represents the fluorescence intensity of the solutions and S represents the surface area of the glass tubes.

We previously reported the purification of a serine proteinase from the venom of the sharp-nosed pit viper (Deinagkistrodon acutus) using a combination of affinity chromatography and ion-exchange chromatography [Xin, Dong, Wang and Li, R. (2007) J. Chromatogr. B 859, 111-118]. The high fibrinogen-clotting activity [2025 NIH (National Institutes of Health) units/mg] of this protein indicated that it may have great potential as a drug for treating thrombolysis. In order to systemically determine the purified protein's structure and activity, it was characterized using the following methods: MS, isoelectric focusing, deglycosylation analysis, amino acid composition analysis, peptide mass fingerprinting, N-terminal amino acid sequencing, CD, hydrophobic-site analysis and bioactivity assays. In addition, a fluorescence probe was synthesized and conjugated to the protein in order to analyse its active site. The results indicated that the protein is a novel acutobin-like enzyme (designated acutobin II) with strong clotting and esterase activities and is composed of a 28 kDa peptide chain plus approx. 6 kDa of O-linked glycan chains. The protein contains 249 amino acids and, remarkably, no tryptophan residues. The pI of the protein is 4.8+/-0.2. The protein's secondary structure is dominated by beta-sheets (49%) and random coils (43%), and its tertiary structure does not contain any metal ions or disulfide bonds and possesses only one hydrophobic pocket. Analysis revealed that the hydrophobic pocket is most likely the enzymatic active site.

Background Lymphopenia promotes naïve T-cell homeostatic proliferation and adoptive effector T-cell survival and memory formation. IL-7 plays a critical role in homeostatic proliferation, survival and memory formation of naïve T-cells in lymphopenia, and its underlying molecular mechanism has also been well studied. However, the mechanism for adoptively transferred effector T-cell survival and memory formation is not fully understood. Here, we transferred in vitro-activated transgenic OT-I CD8+ effector T-cells into irradiation (600 rads)-induced lymphopenic C57BL/6, IL-7 knockout (KO) and IL-15 KO mice, and investigated the survival and memory formation of transferred T-cells in lymphopenia. Results We demonstrate that transferred T-cells prolong their survival and enhance their memory in lymphopenic mice, in a manner that depends on IL-15 signaling, but not IL-7. We determine that in vitro stimulation of naïve or effector T-cells with IL-7 and IL-15 reduces IL-7Rα, and increases and/or maintains IL-15Rβ expression, respectively. Consistent with these findings, the expression of IL-7Rα and IL-15Rβ is down- and up-regulated, respectively, in vivo on transferred T-cells in an early phase post T-cell transfer in lymphopenia. We further show that in vitro IL-15 restimulation-induced memory T-cells (compared to IL-2 restimulation-induced effector T-cells) and in vivo transferred T-cells in irradiated IL-15-sufficient C57BL/6 mice (compared to IL-15-deficient IL-15 KO mice) have increased mitochondrial content, but less NADH and lower mitochondrial potential (ΔΨm), and demonstrate greater phosphorylation of signal transducers and activators of transcription-5 (STAT5) and Unc-51-like kinase-1 (ULK1), and higher expression of B-cell leukemia/lymphoma-2 (Bcl2) and memory-, autophagy- and mitochondrial biogenesis-related molecules. Conclusion Irradiation-induced lymphopenia promotes effector T-cell survival via IL-15 signaling the STAT5/Bcl2 pathway, enhances T-cell memory formation via IL-15 activation of the forkhead-box family of transcription factor (FOXO)/eomesodermin (Eomes) memory and ULK1/autophagy-related gene-7 (ATG7) autophagy pathways, and via IL-15 activation of the mitochondrial remodeling. Our data thus identify some important targets to consider when designing potent adoptive T-cell immunotherapies of cancer. Electronic supplementary material The online version of this article (doi:10.1186/s13578-016-0098-2) contains supplementary material, which is available to authorized users.