Molecular cloning and characterization of Cup a 4, a new allergen from Cupressus arizonica.
Sensitization to Cupressaceae pollen has become one of the most important causes of pollinosis in Western countries during winter and early spring. However, the characterization of the extracts, the allergens involved and the cross-reactivity with other pollen sources still remain poorly studied; in the case of Cupressus arizonica only two allergens have been described so far. A new allergen from C. arizonica pollen, Cup a 4, was cloned and expressed in Escherichia coli as an N-terminally His-tag recombinant protein that was characterized biochemically, immunologically and by circular dichroism spectroscopy. The new allergen has high sequence identity with Prickly Juniper allergen Jun o 4 and contains four EF-hand domains. The recombinant protein has structural similarities with other calcium binding allergens such as Ole e 3, Ole e 8 and Phl p 7. Cup a 4 is expressed in mature pollen grains and shares antigenic properties with the recombinant form. Sera from 9.6% C. arizonica allergic patients contain specific IgE antibodies against recombinant Cup a 4.
Pico de Coaña
Yago
Y
Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain. ypico@cbm.uam.es
Parody
Nuria
N
Fuertes
Miguel Ángel
MÁ
Carnés
Jerónimo
J
Roncarolo
Daniela
D
Ariano
Renato
R
Sastre
Joaquín
J
Mistrello
Gianni
G
Alonso
Carlos
C
D000595:Amino Acid Sequence; D052179:Antigens, Plant / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D003001:Cloning, Molecular; D029781:Cupressus / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D008969:Molecular Sequence Data; D011058:Pollen / Q000235:genetics / Q000276:immunology*; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D006255:Rhinitis, Allergic, Seasonal / Q000097:blood / Q000276:immunology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D052179:Antigens, Plant; D007106:Immune Sera; D011994:Recombinant Proteins; D007073:Immunoglobulin E