Do haptens possess both immunogenicity and reactivity?

Do haptens possess both immunogenicity and reactivity?

• A. Yes, both immunogenicity and reactivity
• B. Only immunogenicity
• C. Only reactivity
• D. Neither immunogenicity nor reactivity

Answer: (C)

Haptens are small molecules that, by themselves, do not possess the ability to elicit an immune response, which is referred to as immunogenicity. They can only be recognized by the immune system when they are attached to a larger carrier protein, making them more recognizable as part of the immune response. This is why the correct understanding is that haptens only exhibit reactivity; they can react with antibodies or the components of the immune system once they are bound to a carrier but do not initiate an immune response on their own. Immunogenicity requires a certain size and complexity that haptens lack, thus confirming that they possess only the capacity to interact or react but not to independently induce an immune response.