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The binding of Griffonia simplicifolia agglutinin-I (GSA-I) and the isolectins GSA-I-AB3 and GSA-I-B4, having affinity for some alpha-D-galactosyl and N-acetyl galactosaminyl residues was studied in different mouse tissues. In brain, cardiac muscle and skeletal muscle, the GSA-I-lectin conjugates showed prominent binding only to blood vessel endothelia. Similarly, in the liver and kidney cortex the GSA-I-conjugates selectively reacted with endothelial cells of the sinusoids and with intertubular and glomerular capillaries, respectively. However, a strong reactivity with the GSA-I-conjugates was additionally seen in the acinar cells of the pancreas, in the stratified squamous epithelia of skin and tongue, and in transitional epithelium. SDS-PAGE electrophoresis combined with the lectin-blotting technique indicated that a similar set of glycoproteins are responsible for the GSA-I binding, even in different tissues. Another lectin with specificity for alpha-D-galactose, the Maclura pomifera agglutinin, displayed a distinctly different distribution of binding sites, mainly in the basement membranes, of all mouse tissues studied. The results suggest that some alpha-D-galactosyl residues, recognized by the binding of GSA-I lectins, are preferentially expressed in endothelial cells of mouse tissues, and also provide further evidence that endothelial cells can present a highly specific surface glycosylation pattern.

Abstract. We studied the distribution of the 0/1-0/6 subunits of BI integrins in developing and adult human kidney using a panel of mAbs in indirect immunofluorescence microscopy.Uninduced mesenchyme displayed a diffuse immunoreactivity for only the 0/1 integrin subunit. At the S-shaped body stage of nephron development, several of the 0/subunits were characteristically expressed in distinct fetal nephron segments, and the pattern was retained also in the adult nephron. Thus, the 0/i subunit was characteristically expressed in mesangial and endothelial cells, the 0/2 in glomerular endothelium and distal tubules, the 0/3 in podocytes, Bowman's capsule, and distal tubules, and the 0/6 subunit basally in all tubules, and only transiently in podocytes during development. Unlike the 0/3 and or6 subunits, the t~2 subunit displayed an overall cell surface distribution in distal tubules. It was also distinctly expressed in glomerular endothelia during glomerulogenesis. The B4 subunit was expressed only in fetal collecting ducts, and hence the 0/6 subunit seems to be complexed with the B1 rather than f14 subunit in human kidney. Of the two fibronectin receptor 0/subunits, 0/4 and 0/5, only the latter was expressed, confined to endothelia of developing and adult blood vessels, suggesting that these receptor complexes play a minor role during nephrogenesis.The present results suggest that distinct integrins play a role during differentiation of specific nephron segments. They also indicate that 0/3fll and otd31 integrin complexes may function as basement membrane receptors in podocytes and tubular epithelial cells.

Rapeseed, raspberry, and pine bark are promising bioactive sources of plant phenolics selected from among ca. 100 previously screened plant materials for in vitro preclinical evaluation of health related effects. Phenolic extracts and isolated fractions of the selected materials were investigated for antioxidant, antimicrobial, antiinflammatory, and antimutagenic properties as well as for cell permeability. It was shown that rapeseed and pine bark phenolics and raspberry anthocyanins were good or excellent antioxidants toward oxidation of phosphatidylcholine membrane (liposomes), rapeseed oil (crude) phenolics were effective radical scavengers (DPPH test), and both raspberry and pine bark phenolics inhibited LDL oxidation. Rapeseed oil phenolics, principally vinylsyringol, raspberry anthocyanins, and pinoresinol and matairesinol, the principal components of pine bark phenolic isolate, were effective against formation of the proinflammatory mediator, prostaglandin E(2). Raspberry ellagitannins inhibited the growth of Proteus mirabilis and Klebsiella oxytoca. Pine bark and rapeseed had minor effects on the permeability of model drugs in Caco-2 experiments. None of the tested extracts were mutagenic nor toxic to Caco-2 cells or macrophages. Thus, phenolic isolates from rapeseed, raspberry, and pine bark and are safe and bioactive for possible food applications including functional foods intended for health benefit.