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A state of insulin resistance has been demonstrated in active preeclampsia, and women with clinical evidence of insulin resistance are at higher risk to develop this syndrome during pregnancy. Recently, inositol phosphoglycan P-type, a putative second messenger of insulin action, has been implicated in the pathophysiology of preeclampsia and is increased in the placenta, amniotic fluid, and maternal urine of preeclamptic women compared with normal pregnant women. We report here a case–control study to assess the potential of urinary levels of inositol phosphoglycan P-type as a screening test for preeclampsia. Twenty-seven preeclamptic women and 47 healthy pregnant women were recruited. A polyclonal antibody-based ELISA was developed to detect levels of inositol phosphoglycan P-type in urine. Its content in urinary specimens was found to be 30-fold higher in preeclamptic subjects than control subjects (329.1±21.8 versus 9.2±1.5; P 1 gestational date sample of urine was available, and retrospective analysis showed a significant time-related increase of the urinary level of inositol phosphoglycan P-type ≤7 weeks before clinical diagnosis of preeclampsia. Urinary level of inositol phosphoglycan P-type increased after diagnosis indicating a possible pathophysiological threshold level and steeply decreased after delivery.

Although plant biotechnology has been widely investigated for the production of clinical-grade monoclonal antibodies, no antibody products derived from transgenic plants have yet been approved by pharmaceutical regulators for clinical testing. In the Pharma-Planta project, the HIV-neutralizing human monoclonal antibody 2G12 was expressed in transgenic tobacco (Nicotiana tabacum). The scientific, technical and regulatory demands of good manufacturing practice (GMP) were addressed by comprehensive molecular characterization of the transgene locus, confirmation of genetic and phenotypic stability over several generations of transgenic plants, and by establishing standard operating procedures for the creation of a master seed bank, plant cultivation, harvest, initial processing, downstream processing and purification. The project developed specifications for the plant-derived antibody (P2G12) as an active pharmaceutical ingredient (API) based on (i) the guidelines for the manufacture of monoclonal antibodies in cell culture systems; (ii) the draft European Medicines Agency Points to Consider document on quality requirements for APIs produced in transgenic plants; and (iii) de novo guidelines developed with European national regulators. From the resulting process, a GMP manufacturing authorization was issued by the competent authority in Germany for transgenic plant-derived monoclonal antibodies for use in a phase I clinical evaluation. Following preclinical evaluation and ethical approval, a clinical trial application was accepted by the UK national pharmaceutical regulator. A first-in-human, double-blind, placebo-controlled, randomized, dose-escalation phase I safety study of a single vaginal administration of P2G12 was carried out in healthy female subjects. The successful completion of the clinical trial marks a significant milestone in the commercial development of plant-derived pharmaceutical proteins. The authors acknowledge funding from the European Union for the Pharma-Planta project (LSHB-CT-2003-503565) as well as additional funding for related and follow-on projects including CoMoFarm (227420), the COST Action Molecular Farming (FA0804), the Grand Challenges in Global Health and the Wellcome Trust (37872) and the ERC advanced grant FuturePharma (269110). We also would like to thank Fraunhofer Gesellschaft for strategic funding.

The plant alkaloids castanospermine, dihydroxymethyldihydroxypyrrolidine and deoxynojirimycin have recently been shown to have potential anti-HIV activity [(1987) Proc. Natl. Acad. Sci. USA 84, 8120-8124; (1987) Nature 330, 74-77; (1987) Lancet i, 1025-1026]. They are thought to act by inhibiting alpha-glucosidase I, an enzyme involved in the processing of N-linked oligosaccharides on glycoproteins. We report here the relative efficacy of a spectrum of amino-sugar derivatives as inhibition of HIV cytopathicity. Several alpha-glucosidase inhibitors and alpha-fucosidase inhibitors were found to be active at concentrations which were non-cytotoxic.

Using data obtained from both one-dimensional and two-dimensional Nuclear Overhauser effect measurements, we have extended our original observations [FEBS Lett. (1983) 150, 503–506] upon the preferred conformer of the complex-type oligosaccharide unit derived from human serum transferrin. We propose that the Galβ1—4GlcNAcβ1—2Manα1—3Manβ1—4GlcNAcβ1—4GlcNAc unit has continuous secondary structure, and that the α(1–6) antenna extends from this structure with no single preferred orientation. Within the α(1–6) antenna, however, a segment of secondary structure (Galβ1–4GlcNAcβ1–Manα1–) exists with a preferred conformation which is probably identical to that found in the α(1–3) antenna.

The conformation in solution of the biantennary complex type oligosaccharide unit derived from human serotransferrin has been investigated using 1H-1H Nuclear Overhauser Effect (NOE) measurements at 300 MHz. From quantitation of the NOE, the alpha(1-3) antenna is shown to exist in a preferred solution conformation with respect to the mannosyl-chitobiose core. The flexibility of the alpha(1-6) arm, together with the absence of NOE data between this arm and the core, indicates that, in contrast to the alpha(1-3) arm the alpha(1-6) arm has no preferred conformation with respect to the core.

An NMR method is described, based on coherence transfer in the rotating frame, which allows for the rapid determination of proton resonance assignments in oligosaccharides. The composite one-dimensional spectrum of the oligosaccharide is decomposed into a subset of spectra that are derived from individual monosaccharide residues. Proton resonance assignments can be obtained from these subspectra by inspection of the multiplicities of the component resonances and by spectral simulation. The method is shown to have particular value in the assignment of proton resonances derived from primary sequence branch-point residues, which often have complex spin-coupling patterns. Other advantages of this method over conventional techniques are discussed.

The stereochemical outcome of the azide displacement of triflates derived from a piperidin-3-ol depends on the protecting group on the ring nitrogen and allows the synthesis of 2-acetamido-1,5-imino-1,2,5-trideoxy-D-glucitol (a potent and specific inhibitor of a number of β-N-acetylglucosaminidases) and of 2-acetamido-1,5-imino-1,2,5-trideoxy-D-mannitol.

Using a combination of /sup 1/H NMR nuclear Overhauser effect measurements, molecular orbital calculation, and molecular dynamics simulations, the authors have determined the tertiary structure and dynamic properties of the oligomannose oligosaccharide Man..cap alpha..6(Man..cap alpha..3)Man..beta..6(Man..cap alpha..3)Man..beta..4GlcNAc..beta..4GlcNAc. While the calculated potential surfaces for the majority of the glycosidic linkages could be described by a single deep potential well, similar calculations for the Man..cap alpha..1-6Man..cap alpha.. and Man..cap alpha..1-6Man..beta.. linkages described a diffuse, shallow well, suggesting that a larger degree of flexibility exists about the latter. These conclusions are supported by the results of molecular dynamics simulations, which suggest that the NMR data should be interpreted in terms of a degree of flexibility about the Man..cap alpha..1-6Man..beta.. and Man..cap alpha..1-6Man..cap alpha.. linkages. In contrast, a similar series of investigations suggests that the conformation of the Man..cap alpha..1-6Man..beta.. linkage in Man..cap alpha..2Man6(Man..cap alpha..2Man..cap alpha..3)Man..cap alpha..6(Man..cap alpha..2Man..cap alpha..2Man..cap alpha..3)Man..beta..4GlcNAc..beta..4GlcNAc is more restricted, resulting in an overall structure that is restrained.