[Effect of heavy metals on immune reactions in patients with infertility]. / Vliv tezkých kovu na imunitní reakci u pacientu s prokázanou neplodností.

BACKGROUND: Heavy metals can negatively influence reproduction because in sensitive persons they are able to alter the immune reactions including autoantibodies production. The altered immune reaction can then cause infertility. METHODS AND RESULTS: The in vitro lymphocyte reaction after stimulation with metals, the production of interferon (IFN-gamma) and antisperm antibodies in supernatants after lymphocyte stimulation in patients with infertility and with the antisperm antibodies present in their serum were investigated. The cause of antisperm antibodies presence was not determined. The diagnosis of metal intolerance was performed by the proliferation method modified for metals (Melisa). In supernatants of tissue cultures of lymphocytes without the antigen stimulation and after stimulation with mercury chloride, the in vitro production of gamma interferon and antisperm antibodies was studied by Elisa. More than 50% of patients did not tolerate mercury, iron, aluminium and silver. When the lymphocyte reaction was compared in patients with and without mercury intolerance we found that lymphocytes of patients with mercury intolerance produced less gamma interferon and more antisperm antibodies in supernatants after mercury stimulation of lymphocytes. CONCLUSIONS: In patients with metal intolerance diagnosed by the Melisa test, metal ions released from the dental materials can represent a factor, that does not cause infertility but is able to influence it negatively.

HLA-association in patients with intolerance to mercury and other metals in dental materials.

A group of selected 25 patients with serious intolerance to heavy metals used for dental restoration were examined for HLA antigens. A significant increase for HLA -- B37, B47 and DR4 was found. The value of the relative risk is not significant after correction for the number of antigens tested and therefore further studies of more patients are needed.

Mercury-specific lymphocytes: an indication of mercury allergy in man.

In this study, 18 patients with oral lichen planus (OLP), adjacent to amalgam fillings, were tested in vitro with an optimized lymphocyte proliferation test, MELISA (memory lymphocyte immunostimulation assay) and with a patch test. Twenty subjects with amalgam fillings but without oral discomfort and 12 amalgam-free subjects served as controls. The results show that patients with OLP have significantly higher lymphocyte reactivity to inorganic mercury, a corrosion product of amalgam, compared to control groups. Removal of amalgam fillings resulted in the disappearance of oral mucosal changes, thus indicating a causal relationship. Positive responses to phenylmercury (phenyl-Hg), a bactericidal agent in root fillings and in pharmaceutical preparations, were also noted in the oral lichen group but not in the control groups. Thus, low-grade chronic exposure to mercury may induce a state of systemic sensitization as verified by Hg-specific lymphocyte reactivity in vitro.

MELISA-an in vitro tool for the study of metal allergy.

The sensitizing properties of metals widely used in medical and dental care have been studied with the help of an optimized lymphocyte proliferative assay, MELISA. MELISA (memory lymphocyte immuno-stimulation assay) was originally developed for the screening of allergenic epitopes of drugs and other chemicals of low molecular weight, but has recently been adapted for the study of metal-induced sensitization. The patients studied suffered from various oral mucosal problems which were suspected to be caused by the release of metal ions from dental restorations. They were also troubled by chronic fatigue persisting over many years. One patient was also occupationally exposed to metals while working in a dental practice. Healthy subjects without any discomfort due to metal devices served as controls. In addition to metals used in dentistry, lymphocyte responses to organic mercurials used widely as preservatives in vaccines, eye/nose drops and contact lense fluids were studied. The results indicated that mercurials, as well as other metals such as gold or palladium, induce strong lymphocyte proliferative responses in patients with oral or systemic symptoms, but not in similarly exposed unaffected subjects. The results of MELISA performed with a pair of identical twins with chronic fatigue syndrome (CFS) indicated that metal-specific responses may be dependent on the genetics of the patient. Thus, many metals that are today accepted for use in medicine and dentistry carry a definite sensitizing risk for certain genetically predisposed individuals. Therefore, the use of these metals should be limited in the future.

Lymphocyte transformation test for diagnosis of isothiazolinone allergy in man.

The lymphocyte transformation test (LTT) has been used for evaluation of in vitro lymphocyte responses in 18 patients with dermatitis and positive patch tests to 200 ppm of a combination of 5-chloro-2-methylisothiazolinone and 28methylisothiazolinone (MCI) in nine patients with dermatitis unrelated to MCI and in seven subjects without skin diseases. Two workers sensitized by occupational exposure to a formulation containing 1,2-benzisothiazolin-3-one (BIT) were also studied. Lymphocytes from nine patch-test-positive patients proliferated vigorously to MCI in vitro. Lymphocytes from the remaining nine patients were not stimulated. Lymphocytes from two BIT-sensitized workers responded to BIT in vitro. The lymphocyte proliferation to isothiazolinones indicates the presence of memory cells in the patients' blood and confirms immunologic reaction to the inducing agent. To establish clinical relevance of LTT results, 12 MCI patch-test-positive patients underwent "use test" with lotion containing 15 ppm MCI. Four of five LTT-positive patients were use-test-positive, whereas seven of seven LTT-negative patients were use-test-negative. LTT-positive and lotion-positive patients responded to 100 ppm or lower concentrations of MCI on patch testing, whereas seven of eight LTT-negative and lotion-negative patients responded to 200 ppm only. In the case of MCI, proliferation was due to the chlorinated component, indicating that this part contains an allergenic epitope. Finally, MCI-specific lymphocyte proliferation was observed only in patients with MCI-positive skin test, but not in nine patients with dermatitis induced by other agents, or in seven subjects without skin diseases. Thus, the lymphocyte transformation test is able to distinguish between irritant and allergic skin responses. It may also be valuable in establishing the clinically relevant patch-test concentration of allergens with irritative properties.

Side-chain-specific lymphocyte responses in workers with occupational allergy induced by penicillins.

Eight workers with clinically diagnosed or suspected occupational allergy caused by penicillins were studied by the lymphocyte transformation test (LTT) and by skin test. The majority of the workers handled bacampicillin, some of them had been in contact with benzylpenicillin and one worked with azidocillin only. Six workers had eczema and 2 workers suffered from rhinitis only. Lymphocytes from workers with bacampicillin-induced symptoms responded to this drug in vitro by an increased 3H-thymidine incorporation and by lymphoblastogenesis. Bacampicillin-specific allergy had been confirmed by positive patch test in 5 workers. Lymphocytes from bacampicillin-allergic workers did not respond to other penicillins such as benzylpenicillin or azidocillin in vitro. However, such penicillins were antigenic in vitro since lymphocytes from an azidocillin patch test positive worker proliferated on exposure to azidocillin in vitro. The findings at the cellular level were further supported by the specificity of the skin test. Thus, bacampicillin patch test positive workers had a negative skin reaction to benzylpenicillin. In conclusion, these data suggest the role of penicillin side chains in the sensitization process underlying occupational allergy to penicillins. LTT can be used as a tool for studying antigenic specificities involved in a sensitization process leading to penicillin allergy.

The lymphocyte transformation test for diagnosis of drug-induced occupational allergy.

Twenty-five workers with clinically diagnosed or suspected occupational hypersensitivity caused by contact with bacampicillin, alprenolol, and/or quinidine were studied by the lymphocyte transformation test and by skin tests. Ten healthy exposed workers, 16 job applicants, and seven healthy nonexposed laboratory workers served as control subjects. Lymphocyte transformation was measured by 3H-thymidine uptake into DNA and by counting of lymphoblasts on cell smears. Lymphocytes from workers with contact eczema or with eczema in combination with conjunctivitis and rhinitis responded to offending drugs in vitro as demonstrated by an increased 3H-thymidine incorporation and by the presence of lymphoblasts in the cultures. In vitro proliferative responses were reproduced during a 4-year period. Drug-specific allergy was confirmed by positive patch test in most workers with eczema. In addition, bacampicillin-specific lymphocyte proliferation was also observed in workers with suspected bacampicillin hypersensitivity but with negative skin tests. They suffered mostly from eczema in combination with conjunctivitis and rhinitis or from conjunctivitis/rhinitis only. Lymphocytes from most control subjects did not respond in vitro to bacampicillin, alprenolol, or quinidine. Weak proliferative responses to bacampicillin were observed in two of the 16 job applicants. The exquisite specificity of drug-induced lymphocyte responses is demonstrated. Thus, lymphocytes from a quinidine-sensitive worker did not respond in vitro to the quinidine stereoisomer, quinine. Furthermore, lymphocytes from a bacampicillin-sensitive worker responded to some penicillins, such as pivampicillin and ampicillin, but not to others, such as benzylpenicillin or pivmecillinam. These data suggest the role of N-acylamido side chain in the sensitization of lymphocytes from this particular donor. In conclusion, lymphocyte transformation test can be used for the detection of offending agents in occupationally sensitized workers. Furthermore, lymphocytes from such individuals may serve as a model for study of specificity of cellular reactions underlying drug-induced hypersensitivity.