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Calmodulin levels were measured by radioimmuno-assay in freshly isolated and cultured psoriatic human scalp hair follicle cells. The mean value +/- SEM for calmodulin was 1.97 +/- 0.15 ng calmodulin micrograms-1 protein for 16 control subjects whereas calmodulin levels were significantly increased in psoriatic hair follicles, 2.93 +/- 0.26 ng calmodulin micrograms-1 protein (uninvolved skin) for 18 patients and 3.09 +/- 0.21 ng calmodulin micrograms-1 protein for involved skin derived hair follicles for 17 of these patients. In vitro, 3-week-old cultures of psoriatic keratinocytes contained less DNA and more calmodulin per DNA than their normal counterparts. When 6 week-old cultures of psoriatic and control hair follicle keratinocytes were compared, this difference disappeared. These results are related to the state of differentiation of these cultures. more...

Psoriatic human hair-follicle keratinocytes were cultured and then examined using light and electron microscopy. In comparison to control cultures derived from non-psoriatics, there were significant differences: stratification in general was more extensive; suprabasal cells were flat instead of round; there were almost no depositions of basal lamina or of cellular debris on the growth substrate; numerous membrane coating granules and a few keratohyalin granules were present earlier in psoriatic cultures than in control cultures; and the differentiation pattern resulted in an earlier appearance of corneocyte-like cells, and clusters of these corneocyte-like cells appeared to have been shed into the culture medium. As in control cultures, no distinct stratum corneum was found. Whether these differences between psoriatic cultures and control cultures reveal an aberrant differentiation pattern for psoriatic cells in vitro is as yet unknown: due to the faster outgrowth in psoriatic cultures, a multilayered and therefore further-differentiated structure near the hair follicle could be obtained more rapidly in psoriatic than in normal skin. more...

Ornithine decarboxylase activity was measured in skin from 14 normal and 24 psoriatic subjects (with stable plaque type psoriasis vulgaris) using punch biopsies carried out immediately (0 h) and 6 h after stimulation by cellotape stripping. At 0 h, no significant difference was found between normal and involved or uninvolved psoriatic skin, but a significant increase was measured 6 h after tape stripping. This increase was significantly greater in uninvolved and involved psoriatic skin compared with normal skin. Preliminary results indicated that these changes were localized in the epidermis. more...

Metabolites of histidine were determined by high performance liquid chromatography in suction blister fluids from lesions and normal appearing skin of patients with psoriasis and from healthy subjects. There was a significant decrease in the levels of histidine and urocanic acid in the samples obtained from patients with psoriasis as compared to healthy subjects. Virtually only the E-isomer of urocanic acid was detected. more...

Psoriatic human hair follicle keratinocytes can be brought to culture under the same conditions as normal control hair follicle keratinocytes. In comparison with control cultures derived from non-psoriatics there are significant differences. However, no significant differences are found between cultures derived from either psoriatic involved or uninvolved skin. Some characteristics of psoriatic lesions are also encountered in the cultures. However, in contrast to the situation in a psoriatic lesion, cultures of psoriatic keratinocytes differentiate to a higher extent than comparable control cultures. A psoriatic morphology is therefore not completely formed. Whether this is due to the absence of a psoriatic dermis or to the fact that differentiation in culture is incomplete remains to be investigated. more...

It is generally accepted that in psoriasis there is an alteration of epidermal cell proliferation. It has been reported that an increased rate of thymidine incorporation into keratinocytes is found in the upper part of the hair follicle in involved skin, but this is not the case in the lower part. Here we show that cells from psoriatic hair follicles could be brought in culture under the same conditions as those of normal hair follicles. Cells, whether originating from the upper or lower part of the hair follicle sheath either from involved or uninvolved psoriatic skin, show a faster rate of outgrowth in the first days of culture. Moreover, a large number of psoriatic cells have an increased motility in the early stages of culture, as compared to control cells. These properties can no longer be observed after several days in culture. The activity of glucose-6-phosphate dehydrogenase known to be increased in psoriatic plaques is normal in hair follicles isolated from these plaques. Protein gel electrophoretic investigations showed that there is no difference in gel patterns between normal and psoriatic hair follicles. In conclusion, the isolation of human hair follicles represents a simple method that allows psoriatic keratinocytes to be brought in culture and permits the study of certain aspects of the disease. more...

Psoriatic and control human hair follicle keratinocytes were cultured on bovine eye lens capsules in Epicult dishes for a period of 5-6 weeks and examined using light microscopy. The following morphological differences between cultures were observed: 1. The lower cell layers contained predominantly flattened cells in psoriatic cultures instead of roundish in control cultures. 2. The differentiation pattern was irregular in psoriatic cultures instead of regular in control cultures. 3. The differentiated zone of psoriatic cultures was more compact and thicker in comparison to normal cultures. These differences might allow discrimination between normal and psoriatic cultures. more...

Focuses on the mechanism or mode of action of the drug anthralin. Efficacy of the drug in psoriasis; Disadvantages of the medication such as staining and irritation; Subjection of anthralin to light-catalysed oxidation and/or chemical decomposition. more...