antinuclear antibody

medicine

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Last updated

June 18, 2026

Quick Summary

Antinuclear antibodies (ANAs) are a type of autoantibody that targets the nucleus of cells. While most people have some self-reactive antibodies, the presence of ANAs doesn't automatically mean a person has an autoimmune disease. Autoimmune diseases occur when the immune system mistakenly attacks the body's own tissues.12

In conditions like systemic lupus erythematosus (SLE), ANAs are formed against the nucleic acids and proteins within cell nuclei. These antibodies don't harm healthy cells directly because the nucleus is protected inside the cell. However, when cells die or become inflamed, their nuclear contents are released. This allows ANAs to bind with these components, forming immune complexes. These complexes can then deposit in tissues, leading to damage, particularly in organs like the kidneys, joints, skin, heart, and lungs.1

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immune system disorder
Systemic lupus erythematosus
Such autoantibodies, called antinuclear antibodies, do not attack healthy cells, since the nucleus lies within the cell and is not accessible to antibodies. Antigen-antibody complexes form only after the nuclear contents of a cell are released into the bloodstream during the normal course of cell death or as…
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Such autoantibodies, called antinuclear antibodies, do not attack healthy cells, since the nucleus lies within the cell and is not accessible to antibodies. Antigen-antibody complexes form only after the nuclear contents of a cell are released into the bloodstream during the normal course of cell death or as…
Read More

connective tissue disease
Systemic lupus erythematosus
One or more of these antinuclear antibodies are present in virtually all persons with active disease. The first of these antibodies to be recognized was the lupus erythematosus cell factor, discovery of which permitted detection of previously obscure and unrecognized forms of systemic lupus erythematosus.
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One or more of these antinuclear antibodies are present in virtually all persons with active disease. The first of these antibodies to be recognized was the lupus erythematosus cell factor, discovery of which permitted detection of previously obscure and unrecognized forms of systemic lupus erythematosus.
Read More