- I. Die van (1)
- T.M. Falcao Ferreira (1)
- D.E.A. Florack (1)
- D. Ghati (1)
- J.P.F.G. Helsper (1)
- P.J. Hensbergen (1)
- C.H. Hokke (1)
- C.A.M. Koeleman (1)
- L.H.F. Mullenders (1)
- R.E.A. Musson (1)
- J. Pelt van (1)
- G.J.A. Rouwendal (1)
- N.P.M. Smit (1)
- G.M. Stoopen (1)
- W.P.M. Temmink (1)
- A.H. Westphal (1)
- J.H. Wichers (1)
- M. Wuhrer (1)
UVA1 radiation inhibits calcineurin through oxidative damage mediated by photosensitization
Musson, R.E.A. ; Hensbergen, P.J. ; Westphal, A.H. ; Temmink, W.P.M. ; Deelder, A.M. ; Pelt, J. van; Mullenders, L.H.F. ; Smit, N.P.M. - \ 2011
Free Radical Biology and Medicine 50 (2011)10. - ISSN 0891-5849 - p. 1392 - 1399.
singlet molecular-oxygen - light-emission measurements - transcription factor nfat - human skin fibroblasts - kappa-b activity - hydrogen-peroxide - cyclosporine-a - ultraviolet-radiation - phosphatase-activity - human keratinocytes
The protein phosphatase calcineurin has been gradually revealing itself as the central controller of our immune response, although it is involved in a wide array of signaling pathways related to cellular development and cell cycle progression. As such, calcineurin is an attractive, yet delicate, therapeutic target for the prevention of allograft rejection and treatment of several inflammatory skin conditions. However, calcineurin activity is not only sensitive to immunosuppressants such as cyclosporin A and tacrolimus, but also subject to modulation by reactive oxygen species. We have recently shown, both in vivo and in vitro, that UVA1 radiation suppresses calcineurin activity. In this paper, we present evidence that this activity loss is due to singlet oxygen and superoxide generated by photosensitization and show that a closely related phosphatase, PP2A, is not affected. Furthermore, a survey of this damage reveals oxidation of several Met and Cys residues as well as an overall conformational change. These findings provide a mechanistic basis for the hypothesis that UVA1 and calcineurin inhibitors both affect the same signal transduction pathway in skin.
Efficient introduction of a bisecting GlcNAc residue in tobacco N-glycans by expression of the gene encoding human N-acetylglucosaminyltransferase III
Rouwendal, G.J.A. ; Wuhrer, M. ; Florack, D.E.A. ; Koeleman, C.A.M. ; Deelder, A.M. ; Bakker, H. ; Stoopen, G.M. ; Die, I. van; Helsper, J.P.F.G. ; Hokke, C.H. ; Bosch, H.J. - \ 2007
Glycobiology 17 (2007)3. - ISSN 0959-6658 - p. 334 - 344.
asparagine-linked oligosaccharides - glycoprotein-synthesis - substrate-specificity - cdna cloning - hen oviduct - developmental-stage - schistosoma-mansoni - mass-spectrometry - transgenic plants - beta-1-4 linkage
In this study we show that introduction of the human N-acetylglucosaminyltransferase (GnT)-III gene into tobacco leads to highly efficient synthesis of bisected N-glycans. Enzymatically released N-glycans from leaf glycoproteins of wild type and transgenic GnT-III plants were profiled by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) in native form. After labeling with 2-aminobenzamide (2-AB), profiling was performed using normal-phase high-performance liquid chromatography (HPLC) with fluorescence detection, and glycans were structurally characterized by MALDI-TOF/TOF-MS and reverse-phase nano-liquid chromatography-MS/MS. These analyses revealed that most of the complex-type N-glycans in the plants expressing GnT-III were bisected and carried at least two terminal GlcNAc residues in contrast to wild-type plants where a considerable proportion of N-glycans did not contain GlcNAc residues at the nonreducing end. Moreover, we have shown that the majority of N-glycans of an antibody produced in a plant expressing GnT-III is also bisected. This might improve the efficacy of therapeutic antibodies produced in this type of transgenic plant.
Diagnosis of Schistosomiasis by reagent strip test for detection of circulating cathodic antigen
Dam, G.J. van; Wichers, J.H. ; Falcao Ferreira, T.M. ; Ghati, D. ; Amerongen, A. van; Deelder, A.M. - \ 2004
Journal of Clinical Microbiology 42 (2004)12.. - ISSN 0095-1137 - p. 5458 - 5461.
monoclonal-antibodies - mansoni - caa - individuals - immunoassay - senegal - assay - cca
A newly developed reagent strip assay for the diagnosis of schistosomiasis based on parasite antigen detection in urine of infected individuals was evaluated. The test uses the principle of lateral flow through a nitrocellulose strip of the sample mixed with a colloidal carbon conjugate of a monoclonal antibody specific for Schistosoma circulating cathodic antigen (CCA). The strip assay to diagnose a group of highly infected schoolchildren in Mwanza, Tanzania, demonstrated a high sensitivity and association with the intensity of infection as measured both by egg counts, and by circulating anodic antigen and CCA levels determined by enzyme-linked immunosorbent assay. A specificity of ca. 90% was shown in a group of schistosome-negative schoolchildren from Tarime, Tanzania, an area where schistosomiasis is not endemic. The test is easy to perform and requires no technical equipment or special training. The stability of the strips and the conjugate in the dry format lasts for at least 3 months at ambient temperature in sealed packages, making it suitable for transport and use in areas where schistosomiasis is endemic. This assay can easily be developed to an end-user format.