Pollen allergies: the allergy to Parietaria judaica is one of the most widespread in the Mediterranean region
Allergies occur when there is an excessive immune response to normally innocuous substances present in the environment, such as dust, mould and pollen. Pollen is one of the major causes of respiratory allergies. Of these, the allergy to Parietaria judaica is especially widespread among the people of the Mediterranean basin and Southern Italy, where it can affect up to 30% of allergic people.
Treatment that acts not only on the symptoms but also on the cause of pollen allergies is known as allergen-specific immunotherapy. This therapeutic approach involves the controlled administration of the allergen responsible for a specific allergy, with the aim of modifying and lowering the response of allergic people's immune systems. However, there is a paradox here: immunotherapy – also known as ‘anti-allergy vaccination’ – takes the very substance that causes the allergy and uses it in the treatment, which is why there can be side effects. The research conducted by CNR in Palermo is aimed at paving the way for future improvements to these aspects.
Anti-allergy vaccination: the new technique that ‘disguises’ the allergen to avoid an immune response
A research group at CNR in Palermo, comprising experts from the Institute of Biophysics (IBF) and from the Biomedical Research and Innovation Institute, has developed a new methodology that could provide an alternative way of preparing immunotherapy in the treatment of pollen allergies.
The study, published in the magazine ACS Omega, describes an approach that uses nanoparticles obtained from marine microalgae to deliver an allergen of Parietaria judaica into the organism.
Laboratory research demonstrated that the allergen can be concealed inside vesicles, known as nanoalgosomes, with the aim of developing an alternative kind of immunotherapy for allergies.
Mauro Manno, CNR-IBF researcher and study coordinator, explained: “We successfully enclosed the allergen in the vesicles, so that it could not be identified until its release. This meant it could be transported in a controlled way, avoiding side effects. The allergen's invisibility is in fact vital for preventing an allergic response and allowing the allergens to stimulate the organism's immune tolerance. This aspect will be the subject of a later stage of our research”.
To load the allergen, that is, insert the allergen into the nanoalgosomes, the extrusion technique was used, by which the vesicle membrane is subjected to mechanical perturbation, which does not compromise its integrity. The end products are then purified by means of affinity chromatography, a method that enables the removal of molecules not loaded efficiently.
Future perspectives: beyond pollen allergy treatment
According to the researchers, the study demonstrates that the recombinant allergen Par j 4, produced in the laboratory using genetic engineering techniques, yet immunologically equivalent to the natural allergen, can be loaded into the nanoalgosomes to make it undetectable from the outside.
The research highlighted how the results provide an important component in the search for environmentally sustainable solutions, which put patients’ safety first; nanoalgosomes are non-toxic particles that do not stimulate the organism to produce antibodies, which makes them ideal for use in treatment. Indeed, the ability to disguise allergens, reducing their absorption and lowering the immune response, opens up new possibilities for improving the safety of immunotherapy.
Further studies will nevertheless be needed in order to test this technology on actual cells or biological tissues, and to verify that the mechanism observed in the laboratory also functions under biological conditions that are closer to those in humans. More generally, the same technology could also be applied in other fields, such as the nutraceutical or cosmetic sectors.
