You always have the genetic predisposition to hypersensitivity. However, if you are made insensitive to your allergens and if the doc helps you understand how to stay symptom-free then you might remain free of hypersensitivity reactions so long as you prevented or avoided the beginning of a new increase of you allergic symptoms. Keep yourself symptom free and you are not allergic. Not cured, but not allergic. We can do pollens and mold spores because they are hundreds of millions years old and each one is precisely the same as its neighbors.
Every mammal is different.
We can't desensitize you to the beef you eat unless you eat the same cow we used to densisitize you with. We see great increases in allergy when girls go through hormone changes, say at puberty and again in peri-menstrual years. Men when they get older make less cortisol. Last time you were here, you said that asthma is an allergy. If the immune system functions correctly it attacks bacteria, viruses and toxins.