Cloning and expression of the allergen Cro s 2 profilin from saffron (Crocus sativus).

BACKGROUND

Profilin is a panallergen that is recognized by IgE in allergic patients. Allergy to saffron (Crocus sativus) pollen has been described in people exposed to its pollen. Saffron contains a profilin that may cause allergic reactions in atopic subjects. The aim of this study was to describe the cloning, expression and purification of saffron profilin from pollen.

METHODS

Cloning of saffron profilin was performed by polymerase chain reaction using specific primers from saffron pollen RNA. Expression was carried out in Escherichia coli BL21 (DE3) using a vector pET-102- TOPO. A recombinant fusion protein was expressed and the recombinant profilin was purified by metal precipitation. Immunological characterization was performed by immunoblotting experiments.

RESULTS

The 34kDa- recombinant saffron profilin, Cro s 2, as a fusion protein was purified. Immunoblotting tested with the sera of allergic patients showed a specific reaction with the recombinant Cro s 2 band.

CONCLUSIONS

The sequence of Cro s 2 showed a high degree of identity and similarity to other plant profilins and the recombinant saffron profilin, Cro s 2, may be used for target-specific diagnosis and structural analyses and investigation of cross reactivity of Cro s 2 with other plant profilins.