The immune profile of contact allergy patients.

Nonspecific parameters of antibody-related and cellular immune responses were studied in a group of 30 patients treated for manifest contact allergy to metals (chromium, cobalt, nickel) or non-metals (epoxy resin, rubber) confirmed in each of them by specific patch test positivity. In addition, every patient was tested for the pattern of skin reactivity to the Immunoskintest (USOL, Prague) antigens administered intradermally. The group of 20 metal allergy patients had decreased suppressor index values, enhanced formation of immediate active rosettes and an elevation of serum IgM and IgA immunoglobulins. The remaining 10 patients reacted by a reduced ability of neutrophils to exert phagocytic action on HEMA particles and a decrease in levels of alpha-2-macroglobulins in serum. This may help select a series of suitable immune parameters to be used as prediction tests in the secondary prevention of cases of occupational contact dermatitis.

Factors of humoral resistance in workers exposed to vinyl chloride with a view to smoking habits.

Serum samples were assayed in 110 workers (59 smokers and 51 non-smokers) at PVC manufacturing factory, the results being compared with those obtained in a group of age-matched healthy controls. Non-smokers had significantly higher levels of immunoglobulins (IgG, IgA, IgM), while in smokers there was an increase in IgM only. Lysozyme levels (LYS) were elevated in all exposed subjects, but there was a highly significant decrease in the total protein (TP) content. Alfa-2-macroglobulin (A2M) and orosomucoid (ORO) were also elevated in exposed workers. A significant increase was found in ceruloplasmin (CPL), with smokers having higher levels than non-smokers. No difference was detected between the examined groups in transferrin (TRF) and alfa-1-antitrypsin (A1AT). Exposure duration did not correlate with any of the assayed parameters. The positive correlation of IgA levels and inverse correlation of CPL with age in the control group could not be confirmed in the exposed subjects where a significant inverse correlation between age and AlAT levels, which was found to be positive in exposed non-smokers, proved to be inverse in the subgroup of smokers. The authors discuss possible explanations of the reported findings.

Humoral factors of resistance in the cohort of workers exposed to vinylchloride in the span of six years, concerning the influence of smoking.

A cohort of 66 workers professionally exposed to vinylchloride (VC) in a plant producing polyvinylchloride was examined in years 1979 and 1985 by same methods. Significant changes of the levels of immunoglobulins (Ig), lysozyme and transferrin were not observed during the six years in the subgroup of smokers. Nevertheless a highly significant rise of alpha 2 macroglobulin (A2M) and ceruloplasmin (CPL) levels in this subgroup was stated. The levels of IgA and IgM significantly rose in the subgroup of ex-smokers, as well as highly significant increase of A2M was noted in this subgroup. The levels of IgG and A2M rose with highly significance in the subgroup of non-smokers; the CPL increase was only of weak significance. Many significant differences in means were assessed between subgroups of exposed workers and age matched control persons. No significant correlation between the levels of the tests and the time of exposure to VC was observed by regression analysis. In the discussion an opinion about possible premature aging of persons exposed to VC was brought forward.

Adjuvant activity of muramyldipeptide in a guinea pig model of contact allergy to chromium.

New chemical agents encountered increasingly in the human environment underline the urgent need for a routine testing of their sensitizing potential for man and the development of a suitable experimental model appears to be essential for a reliable assessment of this potential. In our present experiment we studied a guinea pig model of contact hypersensitivity to chromium using as immunoadjuvants Freund's complete adjuvant (FCA) and Freund's incomplete adjuvant (FIA) emulsified with muramyldipeptide. The study showed that the use of adjuvants was essential for inducing the state of hypersensitivity in experimental animals. It was also demonstrated that muramyldipeptide was not only a fully potent substitute for FCA, but was even superior to it in all the parameters tested. The optimal time interval for demonstrating the induced hypersensitivity to chromium was the third week after the onset of sensitization. This animal model appears to be well suited for the experimental testing of contact allergen potentials.

Experimental skin sensitization in guinea pigs verified by the skin test and the lymphocyte migration inhibition test.

The sensitization properties of a number of chemicals were estimated on experimental models, using white female guinea pigs. Sensitization as effected in four ways a) intradermal application jointly with Freund's complete adjuvants (FCA), b) repeated epicutaneous applications together with FCA intradermally, c) a single intradermal application of the tested substance to the ear lobe, d) a single injection of the substance together with FCA into the paws. The results were evaluated with the skin test (ST) and in vitro with the macrophage migration inhibition test (MIT). The suitability of these methodical procedures was verified and agreement in the positivity of the ST and MIT confirmed. The sensitization effect of the tested substance does not depend on the intensity of skin reaction but on the frequency of positive skin test results in the monitored sample.