Allergotoxicology: Research of Pollutant Influence on the Development of Allergic Reactions

Alergotoksikologija je znanstvenoistraživačko područje koje se bavi ispitivanjem utjecaja polutanata (onečišćivača zraka) na nastanak alergijskih reakcija i bolesti. Ispitivanja su prvobitno bila usmjerena na polutante vanjskih prostora, a u novije vrijeme sve više na polutante unutarnjih prostora u kojima ljudi provode većinu vremena. Polutanti po svojoj prirodi mogu biti krute, tekuće ili plinovite čestice, koje se razlikuju s obzirom na veličinu, sastav i izvor iz kojeg nastaju. S obzirom na izvor mogu biti biološkog i nebiološkog podrijetla. Polutanti koji su predmet suvremenih istraživanja s gledišta nastanka alergijskih bolesti su respirabilne krute čestice, ozon, dušični oksidi i bioaerosoli. Mehanizam djelovanja polutanata ovisi o veličini čestica, njihovoj topljivosti i mjestu ulaska u organizam. Dosadašnja ispitivanja su pokazala da različite čestice uvjetuju različite imunosne i neimunosne odgovore u organizmu. Interakcija polutanata i alergena može se zbivati izvan eksponirane osobe, tj. sa samim alergenom ili u eksponiranoj osobi na sluznicama i koži. Polutanti mogu biti nosioci alergena i mogu interferirati na različitim nivoima u nastanku alergijske reakcije. U ovom prikazu razma raju se dosadašnja saznanja o mehanizmima djelovanja polutanata na alergene, na imunosni sustav izloženih osoba na osnovi epidemioloških populacijskih istraživanja, kliničkih studija ekspozcije u kontroliranim uvjetima i eksperimentalnih testnih sistema in vivo i in vitro.Allergotoxicology studies the infl uence of pollutants on the development of allergic reactions and diseases. At the beginning, the research was focused on outdoor air pollutants, while recently it turns to the indoor environment, mainly because people this is where people spend most of their time. Air pollutants may be solid, soluble, or gaseous particles in nature, and they can differ in size, structure, and sources. Pollutants can be of biological or nonbiological origin. Currently interesting air pollutants include particulate matter, ozone, nitrogen oxides, and bioaerosols. The mechanisms of pollutant activity depend on the particle size, solubility, site of deposition, and specifi c chemical properties. Recent studies have shown that different pollutants provoke different immunological and nonimmunological responses in exposed persons. Interaction between air pollutants and allergens can take place outside the exposed person i.e. with allergen itself, or inside the organism on mucous membranes and skin. Pollutants may be the carriers of allergens and may exacerbate allergic reactions and diseases. This review presents recent views about the mechanisms of pollutant activity on allergens and immune system response in exposed persons, based on epidemiological population studies, clinical studies of exposure under controlled conditions, and experimental tests in vitro and in vivo

Repeated delayed-type hypersensitivity reactions against Mycobacterium lepraemurium antigens at the infection site do not affect bacillary multiplication in C3H mice.

Delayed-type hypersensitivity was induced in cyclophosphamide-pretreated C3H/TifBom mice by subcutaneous immunization in the thorax with ultrasonicated Mycobacterium lepraemurium bacilli in Freund incomplete adjuvant. Seven weeks after immunization, 2.5 X 10(7) acid-fast M. lepraemurium bacilli suspended in diluted sonicate were injected into one hind footpad, and during the next 6 weeks three additional infections of sonicate were given at intervals into the infected footpad. After each injection a strong local reaction developed, which after the first three injections peaked at 24 h. The kinetics of the reaction was accelerated after the repeat injections. Each time the reaction subsided within 1 week. From 2 days to 11 weeks after the inoculation of bacilli there was a 10-fold increase in bacillary numbers in the footpad and a 3,000-fold increase in the draining popliteal lymph node. The degree of bacillary multiplication was the same in animals which had experienced repeated local reactions and in control animals. Thus, repeated strong delayed-type hypersensitivity reactions to M. lepraemurium antigens apparently were without any measurable effect on the bacillary multiplication. This observation provides further evidence for a dissociation in C3H/TifBom mice between delayed-type hypersensitivity to soluble mycobacterial antigens and protective immunity against mycobacteria. Possible explanations for our findings are discussed

Cry1Ab protein from Bacillus thuringiensis and MON810 cry1Ab–transgenic maize exerts no adjuvant effect after airway exposure

The genetically modified (GM) maize event MON810 has been inserted with a processed version of the transgene, cry1Ab, derived from the soil bacterium Bacillus thuringiensis (Bt) to express proteins with insecticidal properties. Such proteins may introduce new allergens and also act as adjuvants that promote allergic responses. While focus has been on safe consumption and hence the oral exposure to GM food and feed, little is known regarding inhalation of pollen and desiccated airborne plant material from GM crops. The aim of this study was to investigate whether plant material from the Cry1Ab-expressing maize variety MON810, or trypsin-activated Cry1Ab (trypCry1Ab) protein produced in recombinant bacteria, may act as adjuvants against the allergen ovalbumin (OVA) in a mouse model of airway allergy. A clear proallergic adjuvant effect of the mucosal adjuvant cholera toxin (CT) was demonstrated, determined as increased specific IgE, eosinophils and Th2 cytokines in MLN cell supernates, while no elevation in OVA-specific antibodies or cytokine release from MLN cells after stimulation with OVA were observed in mice receiving Cry1Abcontaining plant materials or the trypCry1Ab protein. Our data suggest that Cry1Ab proteins had no detectable systemic adjuvant effect in mice after airway exposure. Further experiments with purified plant proteins, as well as long-term exposures needs be conducted to further evaluate exposures experienced in real life situation