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Lichen planus (LP) is a mucocutaneous syndrome of yet uncertain pathogenesis, and it has usually been considered to be a dermatosis without antinuclear antibodies (ANA) nor other specific auto-antibodies. Over 10 years ago a series of indirect immunofluorescence researches with patients' lesional skin and serum disclosed the presence of lichen planus specific antigens (LPSA). After this, a number of substrates have been submitted for evaluation. In this study we have carried out indirect immunofluorescent test in relation with different substrates, with the aim of verifying whether the negative results previously obtained were due to poor sensitivity of the substrates employed. Subsequently we have compared the results obtained in the erosive forms of LP with those obtained in the non-erosive forms. We have concluded that rat oesophagus is a better substrate for the detection of ANA in patients with LP, as it has proved to have a positivity rate of 40.42%. Monkey oesophagus has provided a rate of 27.6%, and HEP-2 cells and rat liver have proved to be unsuitable. In addition, we have observed that the frequency of ANA is higher in the erosive forms of LP (P = 0.0389). In this article we demonstrate that the presence of ANA in patients with LP depends on the substrate employed, the most suitable substrate being rat oesophagus. Also, we demonstrate that ANA is more frequently observed in patients with erosive LP.

AM3, a biological response modifier (BRM) of polysaccharide/protein nature, was given by the oral route to 13 patients with chronic active hepatitis B (CAHB). After 12 months of daily treatment, 8 patients cleared serum HBV-DNA and HBeAg together with ALT normalization. Immunohaematologic studies showed how time of inhibition of viral replication was related to significant decreases of CD4, CD8 and B cell blood lymphocytes. After serum viral elimination, however, a significant haematologic rebound of peripheral blood mononuclear cells (PMNC): CD3, CD4 and CD8 lymphocytes was seen. These data, suggest that the antiviral activities of AM3 may be due to its immunodulatory capacities. These promising results, together with the absence of any side effects, justify the entry to trials with a larger number of patients. Furthermore, treatment with AM3 may help to elucidate the pathophysiology of CAHB.

In an open-controlled trial--oral washes (20 patients) versus test (19 patients)--, we have studied the effects of AM3 (a new oral BRM) on clinical evolution of the recurrent stomatitis (RAS) syndrome. The results obtained at 6th month showed significant decreases on ulcer numbers (p less than 0.001) as well as in their mean duration time (p less than 0.001) due to the AM3 treatment. From a pathophysiologic point of view, the study of the NK peripheral blood cells (Leu 11/CD16) suggests the existence of two kinds of RAS-patients: those showing normal NK cell numbers (approximately 33%) and those ones showing a partial lack in the NK numbers (approximately 67%). These results suggest different rational new approaches to treatment, based on new pathophysiological concepts.

A new immunonephelometric method is described for the quantification of antibodies against factor VIII in sera from patients suffering from haemophilia A. We have been able to reduce the reaction time to only 16 minutes, which permits its application to emergency cases. Applying Spearman's test, we have correlated the results obtained by the immunonephelometric and Ruggieri's methods, obtaining r = 0.87, P < 0.01 for n = 11. From the reproducibility studies we obtained SD = 1.16 as maximum dispersion value. Because it is a fully automated method in a continuous-flow system, the possible manual errors are reduced to a minimum; 60 determinations can be carried out in 1 hour.

The application of the histamine liberation test to the diagnosis and follow-up of allergic processes has been pursued by many authors. Since Shore first described a manual fluorimetric technique, efforts have been directed at automating the system and reducing the sample volume. According to the latest contributions by Moneo et al., from 300 to 400 determinations can be carried out in a single work day, and from 40 to 50 determinations with 10 ml of blood. In the present work we present our experienced in updating the technique and the system of preparation of a histamine standard, which we consider of great practical use in the application of this technique routine. Using the standard solution as reference, we calculated total and basal histamine levels in 342 presumed healthy individuals; the mean values were 69.5 ng/ml for total histamine and 8% for basal histamine in males, and 71 ng/ml for total histamine and 6% for basal histamine in females. Age range was from 17 to 57 years, and there were no differences between sexes. The maximum value was 176 ng/ml and the minimum 32 ng/ml. The reaction of O-phthaldialdehyde with histamine is not chemically specific. In the presence of light, aldehydes self-polymerize; moreover, O-phthaldialdehyde can react with other products in addition to histamine. The first problem is avoided by protecting the reagents from light, and the second by using specific absorption and emission filters which do not pick up signals from reaction side products. Nevertheless, at the quantitative level these effects are negligible when compared to other causes which, although not part of the chemical reaction, are also involved in the process (antigen standardization, etc). By means of this technique, from 300 to 400 determinations can be carried out in a single work day, making it possible to use this technique in the daily work routine.

The number of patients clinically suffering from rhinitis and/or asthma is very important in any collective of our society. The usage of drugs with a bronchodilator effect as a symptomatic therapy has been widely studied. However, the appearance of new products which complements the effect of bronchodilator and antianaphylactic union has not been sufficiently studied. The motive of this study is to evaluate the inhibition of histamine as the primary and principal mediator, liberated specifically by the Dermatophagoides pteronyssinus and D. farinae before and four hours after drug administration. Conditions for inclusion were the following: To be affected by rhinitis and/or extrinsic asthma induced by house dust mites. Not to have been previously treated with immunotherapy. Be free of previous prophylactic or symptomatic medication. Prick test positive to house dust mites. Serum IgE concentration higher than 100 U.I./ml. Specific histamine release by antigens with a value lower than 10% of the total histamine. The results obtained were based on 21 patients affected with rhinitis and/or asthma induced by dust mites and show that Procaterol produces a moderate reduction on the liberation of histamine as much as 58.6 and 57.4 for dust mites D. pteronyssinus and farinae respectively, four hours after ingestion.

The quantification of alpha-foetoprotein in dry blood spots from pregnant women was evaluated, using a conventional radioimmunoassay (RIA) with a monospecific antibody. The stability of alpha-foetoprotein in dry blood spots on filter paper was evaluated with respect to mailing, distances travelled, and the existence of high summer temperatures in our region. The results obtained show that the blood alpha-foetoprotein is stable on dry filter spots sent by mail and is stable for up to four weeks at 4, 25 and 37 degrees C. The analytical method used has a minimal detectable concentration of 10 +/- 1.9 international kilo-units/l. Both inter- and intra-assay variabilities are smaller than 10% and this method can provide results comparable with those of conventional serum assays. Results from dry blood spots and serum samples (the latter analysed by both RIA and two-site enzyme immunoassay) exhibited a good correlation (r = 0.98 and r = 0.97, p less than 0.001). The design of the assay and the nature of the samples make this method suitable for a screening programmes for the antenatal detection of open neural tube defects.

The binding of vasoactive intestinal peptide (VIP) and the stimulation of adenylate cyclase were studied in mononuclear cells from human peripheral blood. The binding depended on time, temperature and pH, and was reversible, saturable and specific. Binding studies suggested the presence of 2 classes of binding site: a class with high affinity (Kd = 2.4 X 10(-10)M) and low capacity (8 fmoles/10(6) cells), and a class with low affinity (Kd = 8.0 X 10(-8)M) and high capacity (800 fmoles/10(6) cells) at 15 degrees C. Secretin displaced [125I]VIP from the cells with a 400-fold lower affinity than VIP, but glucagon, somatostatin and insulin did not show any effect. VIP was a potent and efficient stimulator of cyclic AMP production. The stimulation was observed at a concentration as low as 3 X 10(-11)M and depended on time, temperature and pH. Maximal cyclic AMP production (4-fold above basal levels) was observed with 10(-9) M at 15 degrees. Half-maximal response was obtained at 10(-10)M VIP. Secretin was an agonist of VIP but exhibited a 7000 times lower potency. Peripheral blood mononuclear cells constitute an easily accessible and suitable system for the study of VIP action in different physiological and pathophysiological conditions.