Yes.  An application will not be denied if you are allergic to cats.  However, no breed of cat is hypo-allergenic and a very common reason for cats to be abandoned or surrendered is allergies.  All breeds of cats produce the allergen, Fel d 1, in some quantity.  If you apply seeking a hypo-allergenic cat, your application will not be accepted by a foster unless you are willing to take additional measures to treat your allergies such as: OTC medication, prescription medication, air purifiers, or allergy shots.