Expression and characterization of a new isoform of the 9 kDa allergenic lipid transfer protein from tomato (variety San Marzano)

How Do Pollen Allergens Sensitize?

Plant pollen is one of the main sources of allergens causing allergic diseases such as allergic rhinitis and asthma. Several allergens in plant pollen are panallergens which are also present in other allergen sources. As a result, sensitized individuals may also experience food allergies. The mechanism of sensitization and development of allergic inflammation is a consequence of the interaction of allergens with a large number of molecular factors that often are acting in a complex with other compounds, for example low-molecular-mass ligands, which contribute to the induction a type 2-driven response of immune system. In this review, special attention is paid not only to properties of allergens but also to an important role of their interaction with lipids and other hydrophobic molecules in pollen sensitization. The reactions of epithelial cells lining the nasal and bronchial mucosa and of other immunocompetent cells will also be considered, in particular the mechanisms of the activation of B and T lymphocytes and the formation of allergen-specific antibody responses.

Tomato Allergy: The Characterization of the Selected Allergens and Antioxidants of Tomato (Solanum lycopersicum)-A Review

Tomatoes are one of the most broadly produced and consumed crop plants. They are the source of health-promoting nutrients such as antioxidants, including ascorbic acid, polyphenols, or carotenoids. Despite the beneficial role of tomatoes in the daily diet, they have been confirmed as one of the most prevalent allergenic vegetables. Food allergies can cause many clinical symptoms, e.g., in the gastrointestinal tract, skin, and lungs, as well as anaphylactic shock. A huge amount of clinical research has been carried out to improve the understanding of the immunological mechanisms that lead to the lack of tolerance of food antigens, which can result in either immunoglobulin E (IgE)-mediated reactions or non-IgE-mediated reactions. Lifestyle and diet play an important role in triggering food allergies. Allergy to tomatoes is also linked to other allergies, such as grass pollen and latex allergy. Numerous attempts have been made to identify and characterize tomato allergens; however, the data available on the subject are not sufficient.

Assessment of antimicrobial phytopeptides: lipid transfer protein and hevein-like peptide in the prospect of structure, function and allergenic effect

Background

Antimicrobial peptides (AMPs) are unique natural antibiotics that are crucial effectors of innate immune systems in almost all living organisms. Several different plant antimicrobial peptides have been identified and isolated, demonstrating a high level of protection against various types of bacteria, insects, nematodes and other microbes. Along with antimicrobial function, these peptides play a wide range of crucial function in plants, such as regulation of stomata, ion channel, heavy metals and membrane fluidity.

Main body

Antimicrobial peptides show a continuum of toxicity for a variety of plants and animals pathogenic microbes and even show cytotoxicity against cancer cells. Numerous studies have shown that transgenic plants have increased the expression of AMP-encoding genes in response to biotic and abiotic stresses, and plants that express transgenic AMP genes are more responsive to biotic, abiotic and other functions. In addition to being a molecule with protective properties, various allergic reactions are associated with some phytopeptides and proteins, in particular non-specific lipid transfer protein (nsLTP) and peptide-like hevein. Pru p3 from peach is the most clinically important allergen within the nsLTP family that cause real food allergies and also triggers extreme clinical reactions. Similarly, latex-fruit syndrome was primarily associated with well-studied latex allergen Hevein (Hev b8, Hev b6) and class I chitinases.

Short conclusions

Several findings have shown that, in the near future, transgenic plants based on AMPs against the verity of pathogenic fungi, bacteria and other abiotic stresses will be released without any adverse effects. Recent study reason that association of lipid with nsLTP enhances allergic sensitization and hevein-like domain of chitinase I essentially plays a role in cross-sensitivity of latex with different fruits and nuts. This review discusses the structures and various functions of lipid transfer protein and hevein-like peptide.

The diagnosis and management of allergic reactions in patients sensitized to non-specific lipid transfer proteins

Sensitization to one or more non-specific lipid transfer proteins (nsLTPs), initially thought to exist mainly in southern Europe, is becoming accepted as a cause of allergic reactions to plant foods across Europe and beyond. The peach nsLTP allergen Pru p 3 is a dominant sensitizing allergen and peaches a common food trigger, although multiple foods can be involved. A frequent feature of reactions is the requirement for a cofactor (exercise, alcohol, non-steroidal anti-inflammatory drugs, Cannabis sativa) to be present for a food to elicit a reaction. The variability in the food and cofactor triggers makes it essential to include an allergy-focused diet and clinical history in the diagnostic workup. Testing on suspected food triggers should also establish whether sensitization to nsLTP is present, using purified or recombinant nsLTP allergens such as Pru p 3. The avoidance of known trigger foods and advice on cofactors is currently the main management for this condition. Studies on immunotherapy are promising, but it is unknown whether such treatments will be useful in populations where Pru p 3 is not the primary sensitizing allergen. Future research should focus on the mechanisms of cofactors, improving diagnostic accuracy and establishing the efficacy of immunotherapy.

Identification of non-specific Lipid Transfer Protein gene family members in Solanum lycopersicum and insights into the features of Sola l 3 protein

Non-specific lipid transfer proteins (nsLTPs) are characterized by an eight-cysteine motif backbone that is stabilized by four disulphide bonds. The strong interest towards this protein family is mainly due to the fact that nsLTPs are involved in many biological processes and have been identified as major human allergens. Since tomato (Solanum lycopersicum L.) is one of the most consumed and allergenic vegetables, a full characterization of this family is needed. In this study, hidden Markov model profiles were used to identify nsLTPs within the tomato protein complement. Following manual curation, 64 nsLTP genes were classified into six sub-families. Furthermore, nsLTP gene structure, distribution and arrangement along tomato chromosomes were investigated. Available RNA-seq expression profile data and Real-Time PCR analyses were used to derive expression patterns of tomato nsLTPs in different tissues/organs. Non-specific LTP genes with high level of expression in tomato fruits were filtered out since they could play a key role in tomato allergenicity. Among these genes was Solyc10g075090 that encodes the allergen Sola l 3. Finally, cloning, heterologous expression, purification and biochemical characterization of the recombinant protein Sola l 3 was performed.

The effect of organic and conventional farm management on the allergenic potency and bioactive compounds status of apricots (Prunus armeniaca L.)

The present study shows a relationship between the use of organic or conventional practices and the allergenic properties and the bioactive compound content of apricots. The presented results indicate that organic apricots contain significantly more biologically active compounds from polyphenols group 53.75 mg/100 g FW and 31.52 mg/100 g FW and carotenoids 10.90 mg/100 g FW and 8.42 mg/100 g FW in than conventional apricots from polyphenols 16.83 mg/100 g FW and 27.27 mg/100 g FW and carotenoids 4.01 mg/100 g FW and 3.85 mg/100 g FW. Organic fruits are characterized by a higher allergenic potential. The authors of the current research have found a strong relationship between the content of polyphenolic compounds and the content of allergenic proteins for organic apricots R² = 0.9044 and for conventional apricots R² = 0.8169. The main conclusion is that some organic apricots, despite their better quality, would not be recommended for consumption by allergy sufferers.

Interaction of Non-Specific Lipid-Transfer Proteins With Plant-Derived Lipids and Its Impact on Allergic Sensitization

Non-specific lipid-transfer proteins (nsLTPs) represent a family of ubiquitous plant proteins belonging to the prolamin superfamily. nsLTPs are characterized by a globular α-helical structure stabilized by four disulfide bonds and a hydrophobic cavity which acts as ligand-binding site for a broad spectrum of lipids and hydrophobic molecules. nsLTPs are involved in membrane biogenesis and in the adaption of plants to abiotic and biotic stress. They display antimicrobial activity by the ability to permeabilize the cell membrane of phytopathogens. Moreover, in the presence of lipids, nsLTPs are suggested to activate the plant immune system by a receptor-dependent mechanism. Additionally, nsLTPs from pollen and plant-derived food, in particular type 1 nsLTPs (9 kDa), are described as potent allergens. Within the nsLTP family Pru p 3 from peach is the clinically most relevant allergen which can cause genuine food allergy and frequently elicits severe clinical reactions. So far, the allergenic properties of nsLTPs are attributed to both their low molecular mass and their high thermal and proteolytic stability which allow them to reach the immune system in a biological intact form. Recently, the interaction of nsLTPs with lipids has been suggested to increase their allergenic properties and to promote the allergic sensitization to these proteins. This review will summarize the current knowledge on diversity of lipid ligands of plant LTPs, and illustrate recent studies performed with allergenic nsLTPs to investigate the effect of lipid binding on the structural modification and IgE-binding properties of proteins, and finally the potential effect on the innate immune responses.