What is the difference between complete antigen and incomplete antigen?

Answer 1

Complete antigens are able to induce:

Immunogenicity (ability to stimulate and proliferation of specific lymphocytes and antibody production)

Reactivity- Ability to react with activated lymphocytes and the antibodies released in response to them

Incomplete Antigens (Haptens):

Are small molecules such as peptides, nucleotides, and many hormones that are not immunogenic on their own but can become immunogenic when attached to protein carriers. If a hapten links up with the body's protiens, the adaptive immune system may recognize the complex as foreign and mount a harmful attack.

Answer 2

Protein is made from amino acids. Humans can synthesize most of the amino acids that we need to make protein, with the exception of nine essential amino acids (histadine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine) that must come from the foods we eat.

In the early 1900s, studies suggested that rats grew best when fed a combination of plant foods whose amino acid patterns resembled that of animal foods. The term "complete protein" was coined to describe a protein in which all nine essential amino acids are present in the same proportion that they occur in animals. "Incomplete protein" described the varying amino acid patterns in plants. It's a misleading term, because it suggest that humans (and other animals, one would assume) can't get enough essential amino acids to make protein from plants.

Fortunately, the theory that plant proteins are somehow "incomplete" and therefore inadequate has been disproven. All unrefined foods have varying amounts of protein with varying amino acid profiles, including leafy green vegetables, tubers, grains, legumes, and nuts. All the essential and nonessential amino acids are present in any single one of these foods in amounts that meet or exceed your needs, even if you are an endurance athlete or body builder.

Whenever you eat, your body stores amino acids, and then withdraws them when it needs them to make protein. It is not necessary to eat any particular food or any particular combination of foods together at one sitting, to make complete protein. Your body puts together amino acids from food to make protein throughout the day.