Population heterogeneity in the surface expression of Ulex europaeus I-lectin (UEA I)-binding sites in cultured malignant and transformed cells

Expression of the L-fucose moiety on epidermal keratinocytes in psoriasis induced by the Koebner phenomenon: a sequential study

The expression of Ulex europaeus agglutinin (UEA I) binding sites on cell-surface glycoproteins has been used as a marker for terminal differentiation. Increased number of UEA I binding sites of L-fucose specificity have been demonstrated in psoriatic epidermis. The results of lectin-binding studies in a series of biopsies taken sequentially (0 min, 5 min, 24 h, 7 days and 8 weeks) after tape-stripping of uninvolved skin in 12 psoriatic patients (three of whom were taking diltiazem, a calcium blocker at the time of the study) and six controls are presented. UEA I binding sites, which were expressed on the granular layer and upper layers of the stratum spinosum of pre-tape stripped uninvolved skin in psoriatic individuals, were progressively more numerous, with the expression of the L-fucose moiety on the lower stratum spinosum keratinocytes in the 7-day post-tape-stripping biopsies and 8-week biopsies, correlating with a moderate and marked increase in the proliferative index, respectively. In the Koebner-negative and non-psoriatic individuals who failed to develop psoriasis after tape-stripping, the UEA I binding sites were not expressed on keratinocytes of the lower stratum spinosum in any of the biopsies, although a mild increase in the proliferative index was noted in the 7-day biopsies. Our data suggest that the increased commitment of keratinocytes to terminally differentiate may be involved in the psoriatic process.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of the L-Fucose Moiety on Infrainfundibular Follicular Keratinocytes of Terminal Follicles, Its Decreased Expression on Vellus and Indeterminate Follicles of Androgenetic Alopecia, and Re-Expression in Drug-Induced Hair Regrowth

The distribution of various glycoprotein molecules on the surface of follicular keratinocytes was studied with a panel of lectins with specificity for various sugar moieties on biopsy specimens from both bald/balding scalp and normal occipital scalp, of 23 patients with androgenetic alopecia as well as on biopsies of normal forearm skin of four patients. The most significant differences between bald and normal scalp biopsy were noted with Ulex europaeus agglutinin I (UEA I). We noted an increased (91.8% +/- 3.1; mean +/- SE) expression of UEA I binding sites on the infra-infundibular follicular keratinocytes in anagen terminal scalp hairs, compared to 28.5% +/- 5.2 in the indeterminate (anagen) hairs of balding scalps, and 23.2% +/- 6.3 in the anagen follicles of vellus fore-arm hairs. By contrast, the telogen hairs demonstrated minimal UEA I staining: 4.0% +/- 0.8, mean +/- SE in telogen scalp hairs, 1.8% +/- 0.5 in telogen hairs of balding scalps (0% in completely bald scalps, in which all the hairs were in the telogen phase), and 1.9% +/- 0.2 in telogen forearm hairs. The percentage of UEA I staining correlated with the length of the infra-infundibular follicles in all cases studied. In three cases of hair regrowth after hair growth promotors, the UEA I staining increased to 80.6% +/- 6.1 in anagen hairs and correlated with increased length of infra-infundibular follicles. Our data indicate that there are 1) marked differences between anagen and telogen follicles in UEA I binding to infra-infundibular follicular keratinocytes; 2) the percentage of UEA I staining reflects the size (length) of the infra-infundibular hair follicle; and 3) the anagen follicles of balding scalps (indeterminate hairs) show UEA I staining resembling that exhibited by anagen follicles of vellus hairs.

Malignant cell glycoproteins and glycolipids

The cell surface is involved in cell growth and division, cell-cell interaction, communication, differentiation and migration, and other processes likely to be involved in malignant transformation and/or the metastatic spread of cancer. Although there are many alterations of glycoproteins and glycolipids on the malignant cell surface, it is unclear whether these alterations are epiphenomena or an integral part of the malignancy process. This article reviews the recent literature and some earlier studies relevant for understanding emerging concepts and trends with respect to malignant cell glycoconjugates. Emphasis is on structural alterations of the carbohydrate portions of malignant cell glycoproteins and glycolipids and on the enzymes (glycosyltransferases and glycosidases) involved in their metabolism. Practical applications derived from malignant cell glycoconjugate studies are discussed briefly with respect to the diagnosis, staging, monitoring, and treatment of malignant disease. The review concludes by indicating which research areas on malignant cell glycoconjugates are likely to be fruitful in increasing our basic understanding of, and ability to deal effectively with, malignant disease.

Precocious development of lectin (Ulex europaeus agglutinin I) receptors in dome epithelium of gut-associated lymphoid tissues

Dome epithelium (DE), the tissue covering lymphoid domes of gut-associated lymphoid tissues, was examined in both adult and neonatal rabbit appendix or sacculus rotundus to determine if dome epithelial cells matured earlier than epithelial cells covering adjacent villi. The localization of well-differentiated epithelial cells in rabbit gut-associated lymphoid tissues (GALT) was accomplished histochemically by use of molecular probes: fluorescein isothiocyanate or horseradish peroxidase conjugates of Ulex europaeus agglutinin I (UEA), a lectin specific for terminal L-fucose molecules on certain glycoconjugates. The villus epithelial cells of newborn and 2-, 5-, or 10-day-old rabbits did not bind UEA, but between the twelfth and fifteenth days of postnatal life, UEA receptors were expressed by well-differentiated villus epithelial cells. In contrast to villus epithelium, DE in appendix and sacculus rotundus of neonatal rabbits expressed UEA receptors two days after birth, a feature that distinguished the DE of neonatal GALT for the next two weeks. In adult rabbits, UEA receptors were associated with dome epithelial cells extending from the mouths of glandular crypts to the upper domes; in contrast to the domes, UEA receptors were only present on well-differentiated epithelial cells at the villus tips. Results suggested that in neonatal rabbits most dome epithelial cells developed UEA receptors shortly after birth, reflecting precocious development of DE as compared to villus epithelium. In adult rabbit dome epithelium UEA receptors appeared on dome epithelial cells as they left the glandular crypts, representing accelerated epithelial maturation.