CD1a expression in psoriatic skin following treatment with propylthiouracil, an antithyroid thioureylene

BACKGROUND: The antithyroid thioureylenes, propylthiouracil (PTU) and methimazole (MMI), are effective in the treatment of patients with plaque psoriasis. The mechanism of action of the drugs in psoriasis is unknown. Since the drugs reduce circulating IL-12 levels in patients with Graves' hyperthyroidism, the effect of propylthiouracil on CD1a expression in psoriatic lesions was examined in biopsy samples of patients with plaque psoriasis. CD1a is a marker of differentiated skin antigen presenting cells (APC, Langerhans cells). Langerhans cells and skin monocyte/macrophages are the source of IL-12, a key cytokine involved in the events that lead to formation of the psoriatic plaque. METHODS: Biopsy specimens were obtained from six patients with plaque psoriasis who were treated with 300 mg propylthiouracil (PTU) daily for three months. Clinical response to PTU as assessed by PASI scores, histological changes after treatment, and CD1a expression in lesional skin before and after treatment were studied. RESULTS: Despite significant improvement in clinical and histological parameters the expression of CD1a staining cells in the epidermis did not decline with propylthiouracil treatment. CONCLUSIONS: It appears that the beneficial effect of propylthiouracil in psoriasis is mediated by mechanisms other than by depletion of skin antigen-presenting cells

Allergic diseases in the elderly

Demographic distribution of the population is progressively changing with the proportion of elderly persons increasing in most societies. This entails that there is a need to evaluate the impact of common diseases, such as asthma and other allergic conditions, in this age segment. Frailty, comorbidities and polymedication are some of the factors that condition management in geriatric patients. The objective of this review is to highlight the characteristics of allergic diseases in older age groups, from the influence of immunosenescence, to particular clinical implications and management issues, such as drug interactions or age-related side effects

Further Evidence for the Self-Reproducing Capacity of Langerhans Cells in Human Skin

The limited number of Langerhans cells (LC) in the epidermis is one of the main reasons for the technical difficulties in resolving the question of LC kinetics in the present paper, we describe a method to evaluate the LC replication Potential in epidermis The procedure is based on the specific incorporation of bromodeoxyuridine (BrdU), a thymidine analogue, into the DNA during the S-phase of the cell cycle Mice, bearing human skin grafts, were injected s.c. every 6h for up to 17 days with BrdU. At different times, the incorporated BrdU as well as the human epidermal LC were revealed on skin sections using anti-BrdU and OKT-6 monoclonal antibodies, respectively. After 6h, 4. 9% of the LC were labeled with BrdU. Then, the number of OKT-6(+) BrdU(+) cells increased in a linear manner and achieved 34% at 120h, 67% at 240h, and 94% at 400h during the, course of continuous labeling procedures. Based on this result we calculated a total cell cycle time of 392h (16.3 days) and 12h for the S-phase for human epidermal LC.Applying this technique, we were able to show also that 48h after local treatment with 12-O-tretradecanoylphorbol-13-acetate or after stripping, the number of BrdU-labeled LC was considerably increased. Furthermore, after i.p. injection of colchicine in the nude mouse, human epidermal LC undergoing mitosis were evidenced by electron microscopy in the graft. Form these results we conclude that the LC are actively cycling–therewith a self-reproducing cell population in human epidermis

Fluorescence of Photolon photosensitizer entrapped in He-La cells

W pracy badano wnikanie światłouczulacza fotolonu do komórek He-La. Przeprowadzono badania spektroskopowe fotolonu w obecności i bez formaldehydu, stosowanego do utrwalania komórek. Badania mikroskopowe przeprowadzono za pomocą mikroskopu konfokalnego. Komórki inkubowano ze światłouczulaczem przez 4 i 12 godzin. Natężenie fluorescencji fotolonu w komórkach zależy od stężenia roztworu i czasu inkubacji. W wyniku przeprowadzonych pomiarów mikroskopowych wykazano, że czas inkubacji niezbędny do zaobserwowania związku wewnątrz komórek wynosi co najmniej 4 godziny, a minimalne stężenie światłouczulacza 1 mg/ml (1,67 × 10-6 M).The entrapment of the photosensitizer Photolon into the He-La cells, was studied. The fluorescence of photosensitizer was examined without and in the presence of formaldehyde. The study was performed by means of confocal microscopy of cells incubated for 4 hours and 12 hours. It was stated that 4 hours is the shortest time of incubation allowing the observation of Photolon in the He-La cells and the minimal concentration of photosensitizer is 1mg/ml (1,67 × 10-6 M)