Monique Benaissa

Publications (3)0 Total impact

• Article: Molecular cloning and sequence analysis of bovine lactotransferrin

  Annick PIERCE, Didier COLAVIZZA, Monique BENAISSA, Pierrette MAES, André TARTAR, Jean MONTREUIL, Geneviève SPIK
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  ABSTRACT: The screening of a bovine submaxillary gland cDNA library yielded 25 clones coding for bovine lactotransferrin. The nucleotide sequence of the longest insert contained a protein-coding region of 2115 nucleotides and a 3′ non-coding region of 194 nucleotides followed by a poly(A) tract of about 55 nucleotides. The predicted peptide sequence included a 16-amino-acid signal sequence upstream of the first amino acid of the native protein. The identity of the clone was confirmed by matching the amino acid sequence predicted from the cDNA with the N-terminal and tryptic peptide sequences derived from purified bovine milk lactotransferrin, and also by similarity with human and murine lactotransferrins. The cDNA described corresponds to a 705-amino-acid-long preprotein that lacks the start methionine. The sequence of the secreted protein is 689 amino acids long and contains five potential glycosylation sites. Bovine lactotransferrin is 69% and 64% identical to human and murine lactotransferrins, respectively.
  European Journal of Biochemistry. 03/2005; 196(1):177 - 184.
• Article: Expression of the lactotransferrin receptor during the differentiation process of the megakaryocyte Dami cell line

  Nathalie Nillesse, Annick Pierce, Myriam Lecocq, Monique Benaissa
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  ABSTRACT: In order to determine whether the human lactotransferrin receptor recently described on platelets was also present onhematopoietic precursors, we investigated its presence and characteristics on the megakaryocytic Dami cell line. The reversible binding of human 5-([2-(carbo(hydrazino)methyl]thio)acetyl)aminofluorescein-labeled lactotransferrin showed that such a receptor was only present on the subpopulation of the largest cells. The increase in numbers of large cells during culture was paralleled by a concurrent increase in lactotransferrin receptor positive cells. Scatchard analysis of the binding of [125I]-labeled lactotransferrin showed that a single affinity class of binding site was present (Kd = 446 ± 40 nM) and that there were 52 ± 3 × 105 sites per cell. The mouse monoclonal antibody DP5B3G10, specific for the human lactotransferrin receptor, allowed its characterization as a 105 kDa protein on Western blots. The same monoclonal antibody was used to separate the small and large cell subpopulations of Dami cells by panning. Separate culture of the small cells showed that the receptor appeared prior to and independent from endomitosis. In contrast, GPIb was expressed only by large megakaryocytes. The use of conditioned medium from cultures of whole Darni cell populations indicated that a soluble factor is involved in differentiation, but not in the appearance of the lactotransferrin receptor.
  Biology of the Cell.
• Source

  Available from: Laurence Fenart

  Article: Receptor-mediated transcytosis of lactoferrin through the blood-brain barrier

  Carine Fillebeen, Laurence Descamps, Marie-Pierre Dehouck, Laurence Fenart, Monique Benaissa, Geneviève Spik, Roméo Cecchelli, Annick Pierce
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  ABSTRACT: Lactoferrin (Lf) is an iron-binding protein involved in host defense against infection and severe inflammation; it accumulates in the brain during neurodegenerative disorders. Before determining Lf function in brain tissue, we investigated its origin and demonstrate here that it crosses the blood-brain barrier. An in vitro model of the blood-brain barrier was used to examine the mechanism of Lf transport to the brain. We report that differentiated bovine brain capillary endothelial cells exhibited specific high (K<SUB>d</SUB> = 37.5 nM; n = 90,000/cell) and low (K<SUB>d</SUB> = 2 μM; n = 900,000 sites/cell) affinity binding sites. Only the latter were present on nondifferentiated cells. The surface-bound Lf was internalized only by the differentiated cell population leading to the conclusion that Lf receptors were acquired during cell differentiation. A specific unidirectional transport then occurred via a receptor-mediated process with no apparent intraendothelial degradation. We further report that iron may cross the bovine brain capillary endothelial cells as a complex with Lf. Finally, we show that the low density lipoprotein receptor-related protein might be involved in this process because its specific antagonist, the receptor-associated protein, inhibits 70% of Lf transport.
  The Journal of Biological Chemistry.