Diagnostic procedures in immunodermatology

Cutaneous immunofluorescence studies in adult rheumatoid arthritis in sun-exposed and non-sun-exposed areas

The incidence and significance of positive cutaneous immunofluorescence findings were assessed in biopsy specimens of both sun-exposed and non-sun-exposed skin of 34 adult patients with rheumatoid arthritis (RA) who were not receiving systemic corticosteroids. The incidence of lupus erythematosus (LE)-band was low (8.6%) in both groups. Twenty-eight percent of the patients had perivascular IgM and/or C3 deposits, and 74% had cytoid bodies in the papillary dermis. These studies indicate that the incidence of LE band is low in RA and that the detection of such a band in normal skin warrants close follow-up of RA patients for possible development of LE.

Anapsos, an antipsoriatic drug which increases the proportion of suppressor cells in human peripheral blood

Anapsos, an antipsoriatic drug, was administered to normal volunteers in order to study its possible activity on the immune system. After three days of treatment, the drug decreased the lymphoblastic response to PWM and very slightly reduced the serum levels of immunoglobulins. After five days of treatment, however, both values were normal. The response to ConA decreased, and there was an increase in the suppressor index and in the proportion of OKT 8+. The drug did not vary the proportion of OKT 4+ and OKT 3+ cells. These results suggest that anapsos acts by increasing the number of suppressor cells. Such anapsos-induced suppressor cells are probably responsible for the diminished response to ConA, but did not seem to significantly affect response to PWM and serum levels of Ig after five days of treatment.

Immunohistochemistry in cutaneous pathology

Since the first demonstration of skin antibodies in sera of pemphigus patients by IF (Beutner & Jordon 1964), the scope of skin diseases in which immunologic findings may be of interest has enormously enlarged and dermatology remains one of the leading clinical specialities applying IHC in both diagnosis and research. Immunohistological techniques and, to a lesser degree, immunocytological techniques, have been developed to include not only IF, but also immunoenzymatic methods. Even if not all immunological findings may be disease specific and diagnostic, immunohistological techniques have become a very useful tool for studying skin biopsies in connection with serological methods. Their importance could be increased with rapid development of a new field: the study of normal skin constituents; e.g. Ag, collagen, keratin, with the help of specific polyclonal and monoclonal antibodies.

Immunological features of psoriasis. Effects of Ro-109359, concanavalin A, pokeweed mitogen, and methotrexate on cultivated lymphocytes

Isolated peripheral mononuclear cells of psoriasis patients with different disease characteristics, e. g. head-localised, quiescent guttata, confluent active widespread and erythrodermic, were cultured in a modified Mishell-Dutton system. Using the plaque-forming cell (PFC) assay, single cell antibody formation was studied, and class distribution monitored, adding pokeweed mitogen (PWM), concanavalin A (ConA), methotrexate (MTX) or Ro-109359/31, as well as autologous sera to the culture. PFC-estimation vs. sheep red blood cells (SRBC) and burro red blood cells (BRBC) revealed a distinct suppression of primarily IgG-PFC in some of the PWM-treated patients' cultures; ConA maximally reduced PFC by only 50%, compared to 100% for normal immune cells. Ro-109359/31 reduced mainly IgG-PFC in the co-cultures with PWM or autologous sera. MTX resulted in a reduction of IgG-PFC and IgM-PFC equally. The results were compared with cultured immune cells from normal individuals. The two antigenically different indicators, the partial abolition of ConA induced suppression, broad-based immunoglobulin elevation in the sera, and the mainly IgG-formation hint at the role of polyclonal B-cell activation in the perpetuation of psoriasis, which can be specifically reduced by Ro-109359/31. Suppressor cell dysfunctions remain to be discussed.

Studies in cutaneous immunofluorescence. I. The effect of storage time on direct immunofluorescence of skin biopsies from bullous disease and lupus erythematosus

Forty-eight biopsy samples submitted to a diagnostic immunofluorescence service have been stored at -20 degrees C and sequentially re-tested at monthly intervals to ascertain the duration for which immunoglobulins and complement can be identified in these samples in typical and diagnostic patterns of distribution. Four biopsies from pemphigus vulgaris, 14 biopsies from bullous pemphigoid, nine biopsies from dermatitis herpetiformis and 21 from chronic discoid lupus erythematosus have been studied in this manner. In all cases diagnostic immunofluorescence patterns were present up to 4 months after biopsy and in several biopsies a diagnostic pattern was observed at 9 months. It is concluded that adequate storage facilities for a diagnostic immunfluorescence service can be achieved with a -20 degrees C storage system and that known positive material can be retrieved from this system for use as controls or in research studies for a minimum of 4 months.

Defective function of T lymphocytes in psoriasis

The distribution of thymus-derived (T) and bone marrow-derived (B) lymphocytes in 100 patients with psoriasis were studied by the rosetting techniques. Depression of the number of T lymphocytes forming spontaneous rosettes with sheep erythrocytes (E rosettes) occurred in 66% of patients, whereas no difference in B lymphocytes bearing C3 receptor (EAC rosettes) was observed between psoriatics and normals. The decrease in E rosettes was associated with the active phase of the disease. This disappeared 4-6 wk after onset of remission, which suggested that the abnormality in T-cell marker distribution is transitional. Lymphocytes forming neither E nor EAC rosettes, which were found to be significantly increased in active psoriasis, were identified as T lymphocytes since they reacquired normal E rosette function during short-term preincubation with concanavalin A (Con A). A serum factor was also demonstrated which inhibited E rosette formation by normal peripheral blood lymphocytes. Its activity increased linearly within 2 mo from the onset of skin lesions. The data suggest that in active psoriasis serum factors may be coated on the lymphocyte surface membrane which may be responsible for blocking of specific receptor for sheep erythrocytes and/or interfere with T lymphocyte function.