I love cats but i have terrible allergies to them.  It is an alergic reaction to something the cat produces.  Are you allergic?
Oh no! I wonder if it is to the cat's dander? No I am not alllergic to cats. What symptoms do you experience?
I have a coughing fit, wheezing, chest tightening, itching, rash, watering eyes - you name it.  I get it!
That's awful. Have you seen a doctor about it?
Yes the doctor just explained that an allergen is a type of antigen that produces an abnornally vigorous immune response. and he basically recommended that I stay away from cats.  Not much else can be done aparently.
Wow, that's no fun at all.
Immune system
The immune system is a host defense system comprising many biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, and distinguish them from the organism's own healthy tissue. In many species, there are two major subsystems of the immune system: the innate immune system and the adaptive immune system. Both subsystems use humoral immunity and cell-mediated immunity to perform their functions.
Allergy to cats
Cat allergy in humans is an allergic reaction to one or more allergens produced by cats. The most common of these allergens are the glycoprotein Fel d 1, secreted by the cat's sebaceous glands and Fel d 4, which is expressed in saliva. An allergic reaction is a histamine reaction that is usually characterized by coughing, wheezing, chest tightening, itching, nasal congestion, rash, watering eyes, sneezing, chapped lips, and similar symptoms. In some severe cases, reactions may progress rapidly to