antibody: Quick Facts

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Last updated

Oct. 30, 2026

News •

One Dose of Experimental Antibody Kept HIV-Like Virus in Remission For 4 Years in a Monkey • Oct. 26, 2026, 10:01 PM ET (ScienceAlert)

Scientists solve a 30-year mystery behind inflammatory bowel disease • Oct. 26, 2026, 7:58 PM ET (Science Daily)

Your blood could reveal inflammatory bowel disease 10 years before diagnosis • Oct. 24, 2026, 7:54 AM ET (Science Daily)

Immune changes could signal inflammatory bowel disease up to 10 years before diagnosis • Oct. 18, 2026, 6:10 PM ET (Medical Xpress)

New immune profiling tool identifies antibodies that trigger preterm births • Oct. 14, 2026, 12:42 PM ET (News-Medical)

Facts

Also Known As	immunoglobulin • Ig

Photos and Videos

Diagram of an antibody molecule showing two identical light chains and two identical heavy chains joined by disulfide bonds in a Y-shaped structure, with labeled regions for antigen binding and effector function.

Antigens, antibodies, and lymphocytes

Diagram of an antibody molecule showing the Y-shaped structure with labeled variable and constant domains on both light and heavy chains, disulfide bonds holding the folded domains, and antigen-binding sites at the tips.

Diagram showing the five main classes of antibodies: IgG, IgA, IgD, IgE, and IgM, each with labeled light and heavy chains, disulfide bonds, and joining chains, illustrating their structural differences.

Figure 1: The basic four-chain unit of a human immunoglobulin molecule.

Figure 2: A human immunoglobulin molecule showing the domains present in the light (L) and heavy (H) chains.

Diagram showing various proteins of the immunoglobulin superfamily embedded in a cell membrane, including CD4, CD8, CD28, Fc receptor, Thy-1, class I and II MHC proteins, T-cell receptor, and IgM, with disulfide bonds highlighted.

Diagram showing how the flexible hinge regions of antibody molecules allow them to adjust for better binding to antigens and enable cross-linking, forming large antigen-antibody complexes. Antibodies are depicted binding to antigenic determinants on spherical antigens, illustrating both single and cross-linked interactions.

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Topics

rheumatoid factor hyperimmune serum globulin domain autoimmune antibody IgE IgD myeloma protein IgM immune antibody IgG white blood cell autoimmunity complement mast cell lymph mononuclear phagocyte system bone marrow lymphoid tissue peripheral immune tolerance Prolamin

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Key People

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Gregory P. Winter

British biochemst

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James P. Allison

American immunologist

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Tonegawa Susumu

Japanese biologist

Gerald Maurice Edelman

Gerald Maurice Edelman

American physical chemist

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Tasuku Honjo

Japanese immunologist

Bordet, Jules

Jules Bordet

Belgian bacteriologist

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Rodney Robert Porter

British biochemist

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