Monocyte Function in Psoriasis

Abstract

Monocytes derived from the peripheral blood of psoriatic patients demonstrated a significantly higher phagocytic capacity (36 to 40%) for both 125I-labeled Shigella flexneri and 125I-labeled Staphylococcus albus compared with monocytes from healthy subjects. Monocytes from psoriatic patients showed a 2-to-4fold increase in bactericidal capacity against S. albus when compared with normal monocytes. However, the bactericidal capacity of monocytes from diphylline-treated patients did not differ from that of the control subjects. The antibody-dependent cellular cytotoxicity (ADCC) activity against EL4 tumor cells was found to be similar in both psoriatic patients and control subjects. It is postulated that these abnormalities of monocyte function in psoriasis are caused by a decreased cAMP/cGMP ratio similar to the decreased cAMP/cGMP ratio found in the lesional epidermis of this disease. It seems therefore, that the psoriatic abnormality is not confined to only one type of cell, the epidermal cell.

Soluble CD14 Monocyte Antigen in Suction Blister Fluid and Serum of Patients with Psoriasis

“…It has not been possible pre viously to measure monocyte activation by a serum pro tein. Our findings are in accordance with those measuring increased activity of the reticuloendothelial system [24,25] as well as of different monocyte functions in psoriasis including chemotaxis [14,15], aggregation [16], release of lysosomal enzymes [18], phagocytosis [17], angiogenic capability [23], respiratory burst [20,21] and concentration of energy-providing glucose-6-phosphate dehydrogenase activity [19], Increased levels of sCD14 arc not, however, specific for psoriasis as other disorders such as sepsis, poly trauma. endotoxin shock.…”

Cyclic AMP is decreased in mononuclear leukocytes from psoriasis patients

“…Our findings are clearly compatible with the postulate of Bar-Eli et al (1979); tmequivocal proof that the abnormality is located in the monocjrte rather than the lymphocyte must await more refined cell separation techniques. The significance of a monocyte dysfunction in psoriatic patients is of course speculative, but an extremely interesting link has recently been provided by the discovery that the blood monocyte is a precursor of the epidermal Langerhans cell (Katz, Tamaki & Sachs, 1979).…”

Functional Studies of Sessile Macrophages in Liver and Spleen of Psoriatics

“…Exper imental studies revealed close correlations between the central bone marrow pool, the monocyte system, and the tissue-fixed mac rophages. Therefore, results obtained in studying monocytes are comparable to those obtained in tissue-fixed macrophages [6], Signs of activation of monocytes, i.e., macro phages of blood, could be detected by in vitro experiments [3,16,24], Using a skilful in vi vo test system developed by Munz et al [19][20][21][22], we tried to find out if there is any functional alteration of tissue-fixed macro phages in psoriatics.…”

“…According to the thesis of van Furth [6] that tissue-fixed macrophages and blood monocytes belong to the unitary mononuclear phagocyte sys tem, investigations on sessile macrophages and blood monocytes are comparable. A nonspecific activation of blood monocytes in psoriatics could be revealed in vitro [3,16,24]. Polymorphonuclear leukocytes were found to be activated as well: increased chemotaxis [5,14,17,26], phagocytosis [26] and respiratory burst-activity [24].…”