Cell-mediated immune response in psoriasis and psoriatic arthritis.

It has been previously described an impairment of cell-mediated immune response in psoriasis. In the present paper we have evaluated lymphocyte surface markers, non specific immunity, lymphokine secretion and antibody synthesis in a group of patients with psoriasis (PS) and with anti-inflammatory drug treated or gold-treated psoriatic arthritis (PsA). No significant differences are found in terms of T lymphocyte subpopulation frequency, even if a lower CD8+/CD4+ ratio was observed in all patients. In spite of an increased percentage of B lymphocytes, B cell polyclonal response is significantly decreased in the presence of either T cell-independent or T cell-dependent polyclonal activator. Further studies provide additional supports to these findings, since all psoriatic patients exhibit a deficit of T helper function in an antibody-specific induction system. Gold therapy in PsA led to a partial recovery of T helper function, without affecting the immunoglobulin reduced synthesis. With particular reference to non-specific activities mediated by monocytes and polymorphs (PMN), PMN chemotaxis, phagocytosis and killing and monocyte-mediated phagocytosis are reduced, except for monocyte phagocytosis in anti-inflammatory treated PsA or PMN chemotaxis in gold-treated PsA. Finally, lymphokine release is significantly decreased in all patients. In conclusion, our data provide further evidence for the impairment of immune response in psoriasis and PsA, which may in turn play a key role in the pathogenesis of psoriasis.

Histological changes in rabbits after application of medicaments and cosmetic bases (III).

An experimental study is reported of the irritant potential of oil of purcellin , isopropyl palmitate, nonyl phenol, Modulan , Amerchol and Acetulan when massaged in fixed amounts into the rabbit's skin daily for 30 days. Skin biopsies provided data on the number of epithelial cell layers, cell counts of the superficial dermis, and the fibre and basement membrane changes. All the test compounds induced changes in the form of increased number of epithelial cell layers and of the papillary dermis cell count, more marked for Acetulan or Amerchol . The difficulties in the evaluation of the results and their applications to human pathology are discussed.

Experimental sensitization of guinea pigs by drugs. Comparison of the maximization test with the wholly intradermal test.

The capacity of tegobetain, pyrrolnitrin, tolcyclate and chlorquinaldol to induce delayed-type contact sensitization was studied in guinea pigs in 2 series of tests using the method of Magnusson & Kligman and the authors' modification of the wholly intradermal Draize technique. Histological examination of skin biopsies obtained from the test area demonstrated that tegobetain, pyrrolnitrin and tolcyclate are potential sensitizers.

Histological changes in rabbits after application of medicaments and cosmetic bases. II.

A further study of the topical effects of certain pharmaceutical and cosmetic bases on rabbit skin is reported. Cetyl alcohol, myristic acid, castor oil and sorbitol were applied in fixed doses daily for 30 days and their irritant activity was assessed. The macroscopic and microscopic changes were on the whole minimal. Castor oil alone produced some macroscopic alterations in the form of slight erythema and edema, and microscopic changes consisting of acanthosis, disorganization of the basal layer and slight infiltration of the dermis.

Histological changes in rabbits after application of medicaments and cosmetic bases.

A staged histological study of skin changes induced in rabbits by daily application of five bases used for topical medicaments and cosmetics, namely glycols, petrolatum, Modulan, Acetulan and Amerchol L 101, over periods of 100 days, is reported. Sections obtained every 10 days were examined for changes in the epithelium, in the character of the dermal infiltrate and in the superficial collagen fibers. Glycols showed no particular effects on the skin; petrolatum produced acanthosis and vacuolization in the epidermis, and mononuclear cell infiltration of the dermis but evident collagen changes. Lanolin derivatives produced acanthosis and vacuolization of the epidermis, with lymphomonouclear infiltration of the dermis and with dissociation of collagen; examination around the 30th day showed a tendency to basal layer disorganization by the infiltrate.

Histologic aspects of patch test reactions in allergic contact dermatitis.

Twenty subjects with allergic contact dermatitis were patch tested with the responsible allergen applied to four fixed points on the back. Skin biopsies of the four sites were obtained after 6, 12, 24 and 48 hours, fixed in neutral formalin and stained with hematoxylin-eosin, Giemsa and toluidine blue. Sections were examined and lymphomonocytes, mast cells, eosinophils and basophils counted. In all cases the infiltrate consisted mainly of lymphomonocytes (80-82%); mast cells (5%) and basophils (0.2%) do not present clear variations within the given time. Eosinophils showed a definite numerical increase in six cases out of 20.