. Allergopedia

Λεξικό .. Acarus siro

A nonpyroglyphid storage mite which may be of clinical importance, particularly in farmers exposed to hay. A. siro is producing  a high level of alpha-amylase activity. This is attributed to Aca s 4. This enzyme was purified and identified by protein sequencing and LC-MS/MS analysis. Aca s 4 showed a distinct inhibition pattern and an unusual alpha-amylolytic activity with low sensitivity to activation by chloride ions.

Homology modeling of Aca s 4 revealed a structural change in the chloride-binding site that may account for this activation pattern. Aca s 4 was recognized by IgE from house dust mite-sensitive patients, and potential epitopes for cross-reactivity with house dust mite group 4 allergens were found [1].

The allergenic crossreactivity of A. siro and T. putrescentiae with Lepidoglyphus destructor and Dermatophagoides pteronyssinus has been studied with an immunoblotting inhibition technique. Crossreactivity between D. pteronyssinus on the one hand and A. siro and T. putrescentiae on the other, has been shown, as the IgE reactivity to a 25 kDa component of D. pteronyssinus was inhibited to the same degree by extracts of A. siro, T. putrescentiae and D. pteronyssinus.
However, D. pteronyssinus was a poor inhibitor of the allergenic components of A. siro and T. putrescentiae. Strong cross-reactivity has also also been shown between L. destructor and the allergenic components of A. siro and T. putrescentiae, while the latter mite species only to a very low degree inhibited the allergenic components of L. Destructor [2].

1. Pytelková J1, Lepšík M, Sanda M, Talacko P, Marešová L, Mareš M. Enzymatic activity and immunoreactivity of Aca s 4, an alpha-amylase allergen from the storage mite Acarus siro. BMC Biochem. 2012 Jan 31;13:3. doi: 10.1186/1471-2091-13-3.
2. Johansson E1, Johansson SG, Van Hage-Hamsten M. Allergenic characterization of Acarus siro and Tyrophagus putrescentiae and their crossreactivity with Lepidoglyphus destructor and Dermatophagoides pteronyssinus. Clin Exp Allergy. 1994 Aug;24(8):743-51.
3. Gkelis’s Dictionary of Allergy, Vellerofontis Ed., Korinmthos 2014

Γκέλης Ν.Δ. - Λεξικό Αλλεργίας - Εκδόσεις ΒΕΛΛΕΡOΦΟΝΤΗΣ - Κόρινθος 2013

Gelis Ν.D. - Dictionary of Allergies - VELLEROFONTIS Publications - Corinth 2013