IgA

American  

Immunology.

1. immunoglobulin A: a class of antibodies predominant in respiratory and alimentary tract secretions and in saliva and tears, functioning as the body's first line of defense against invading foreign substances especially by neutralizing viral antigens and by preventing the adherence of bacteria to mucous membrane surfaces.

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Etymology

Origin of IgA

First recorded in 1960–65

Example Sentences

Wall Street has been focusing on the company’s next-generation painkiller Journavax, as well as its IgA nephropathy treatment.

From Barron's • Mar. 10, 2026

Vertex acquired the drug, which treats the kidney condition known as IgA nephropathy, when it bought Alpine Immune Sciences for $4.9 billion in the second quarter of 2024.

From Barron's • Mar. 10, 2026

Researchers at Karolinska Institutet in Sweden have shown that nasal drops with IgA antibodies can protect mice from SARS-CoV-2 infection.

From Science Daily • Jan. 10, 2024

In September 2022, she and her colleagues reported that people who were infected early in the pandemic, before they were vaccinated, had detectable levels of SARS-CoV-2–specific antibodies of a type named IgA in their noses.

From Science Magazine • Jan. 24, 2023

IgA and other antibodies are secreted into the intestinal lumen.

From Textbooks • Jun. 9, 2022