Modern problems of sensitization to panallergens

Pan-allergens are molecules, mainly proteins of various families, responsible for cross–reactivity to a wide range of related and unrelated allergens. The clinical significance of having sensitization to some pan-allergens, for example, nsLTP, parvalbumins, storage proteins grows from the fact that severe, generalized reactions can develop, for example, nsLTP syndrome. Sensitization to pan-allergens depends on many factors, such as geographical location, age, food preferences, socioeconomic characteristics of the patient. The aim of the study is to identify the pattern of the sensitization to various molecules of pan-allergens in patients with allergic diseases living in the central part of Russia.

We analyzed the sera of a total of 556 patients with allergic diseases in a multiplex enzyme immunoassay. Six profilin molecules, 2 polcalcin molecules, 12 – nsLTP, and 7 parvalbumin molecules were used.

The frequency of IgE-ab to profilins in patients in central Russia is low (5-7%). At the same time, almost all patients with IgE-ab to profilins have IgE-ab to Bet v 1 (PR-10) and concomitantly to other profilins. In this regard, Bet v 1 can be considered as a primary sensitizer. The peculiarity of sensitization to polcalcins and LTPs was the low frequency of detection of IgE-ab to them (from 0.2% to 3%). At the same time, neither the nsLTP molecules of a peach, nor even apples, which are often consumed in central Russia, provoke the development of nsLTP syndrome. The detection rate of IgE-ab to parvalbumin in the sera of all patients with allergic reactions is also relatively not high and is 7-10%. Whereas the frequency of detection of IgE-ab to parvalbumins in the sera of patients with fish allergy is very high and reaches 63-90%. As a rule, IgE-ab are detected to all molecules, i.e., for parvalbumins of all studied fish species.

The sensitization profile to profilins, polcalcins, nsLTP and parvalbumins in patients living in central Russia has its own unique characteristics. One of the primary sensitizers in patients with sensitization to pollen of wind-pollinated trees is Bet v 1 (PR-10 homologue), IgE-ab to which was detected in 42% of patients. The detection rate of IgE-ab for various molecules of pan-allergens in general was low as follows: profilins – 5-7%, polcalcins – 0.5%, nsLTP – 0.2-3%, and parvalbumins – 7-10%.