Process for producing an allergen extract

1. A process for producing an allergen extract comprising:

a) contacting a source material comprising allergen with acetone to produce a mixture containing lipids dissolved in liquid phase and a solid phase consisting of source material residue comprising allergens and proteins,

b) subjecting the mixture to a first separation step to isolate the source material residue,

c) contacting the source material residue with an aqueous solution to produce a mixture of allergens dissolved in liquid phase, and a solid phase consisting of non-allergenic residue,

d) subjecting the mixture to a second separation step to isolate the allergens dissolved in liquid phase, to produce a crude allergen extract,

e) subjecting the crude allergen extract to a first low molecular fraction removal step to remove molecules having a molecular size of less than 3.5 kDa,

f) carrying out step e) until the crude allergen extract has conductivity of below 1000 μS/cm at 3-5° C. to obtain a purified native allergen extract, and

g) acidifying the purified native allergen extract to pH 2 to 4 to produce an acidified purified native allergen extract and maintaining the acidified purified native allergen extract for 5-30 minutes, followed by subjecting the acidified purified native allergen extract to a second low molecular fraction removal step to remove molecules having a molecular size of less than 3.5 kDa, and adjusting the pH to 7.0-8.0 to produce a depigmented allergen extract.

2. The process as claimed in claim 1 wherein step (f) comprises carrying out step e) until the crude allergen extract has conductivity of less than 500 μS/cm at 3-5° C.

3. The process as claimed in claim 1 wherein the purified native allergen extract is acidified to pH 2 to 2.1.

4. The process as claimed in claim 1 wherein the purified native allergen extract is acidified to pH 2.0 to 3.0.

5. The process as claimed in claim 1 , further comprising a polymerization step, comprising:

h) contacting the depigmented allergen extract with glutaraldehyde or formaldehyde to produce a crude depigmented polymerized allergen extract,

i) subjecting the crude depigmented polymerized allergen extract to a molecular fraction removal step to remove molecules having a molecular size of less than 100 kDa, and

j) carrying out step i) until the crude depigmented polymerized allergen extract has a conductivity of below 210 μS/cm at 3-5° C. and/or is absent of glutaraldehyde as determined by UV or visible scanning, to obtain a purified depigmented polymerized allergen extract.

6. The process as claimed in claim 1 , wherein the source material is selected from the group consisting of food allergens, peanuts, whole peanuts, air-borne allergens, dust mites, fungi, molds, mites, grasses, tree and weed allergens, epithelial allergens, and insect allergens.

7. The process as claimed in claim 5 , wherein the purified depigmented polymerized allergen extract is used in the treatment of an allergy.

8. A process according to claim 5 , wherein step (j) comprises carrying out step i) until the crude depigmented polymerized allergen extract has a conductivity between 50 and 200 μS/cm at 3-5° C.

9. A process according to claim 1 , wherein at least one of the first low molecular fraction removal step in step e) or the second low molecular fraction removal step in step g) comprises an ultrafiltration step, a diafiltration step, a dialysis step or filtration.

10. A process according to claim 6 , wherein the air-borne allergens are pollen, the epithelial allergens are animal hair or animal dander, and the insect allergens are allergens from cockroaches, fleas, bees or wasp venom.

11. A process according to claim 1 , wherein the source material is selected from the group consisting of food allergens, pollen, fungi and molds, epithelial allergens, and insect allergens.

12. A process according to claim 11 , wherein the food allergens are allergens from Arachis hypogaea , the pollen is from Alnus glutinosa, Betula alba, Corylus avellana, Cupressus arizonica, Olea europea, Platanus sp, Cynodon dactylon, Dactylis glomerata, Festuca elatior, Holcus lanatus, Lolium perenne, Phleum pratense, Phragmites communis, Poa pratensis, Ambrosia elatior, Artemisia vulgaris, Chenopodium album, Parietaria judaica, Plantago lanceolata, Salsola kali, Avena sativa, Hordeum vulgare, Secale cereal, Triticum aestivum, Zea mays ), dust mites ( Acarus siro, Blomia tropicalis, Dermatophagoides farinae, Dermatophagoides microceras, Dermatophagoides pteronyssinus, Euroglyphus maynei, Lepidoglyphus destructor, Tyrophagus putrescentiae , the fungi and molds are Alternaria alternate, Cladosporium herbarum , or Aspergillus fumigatus , the epithelias allergens are cat hair, cat dander, dog hair, dog dander, horse hair, horse dander, human hair, human dander, rabbit hair, rabbit dander, or feathers, and the insect allergens are from ants, fleas, mites, cockroaches, wasp venom, or bee venom.

13. A process according to claim 1 , wherein the source material is selected from the group consisting of Arachis hypogaea, Olea europaea pollen, Parietaria judaica pollen, Phragmites communis pollen, Phleum pratense pollen, Dermatophagoides pteronyssinus , and cat dander.

14. A process according to claim 1 , wherein the source material is Arachis hypogaea.