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Updated: Apr 22, 2026

Double Labeling Immunofluorescence using Antibodies from the Same Species to Study Host-Pathogen Interactions
Published on: July 10, 2021
A year in the life of the immunoglobulin superfamily
1MRC Cellular Immunology Unit, Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK.
The superfamily of molecules with immunoglobulin-like domains has recently been gaining new members-largely on the basis of sequence homology. Here Alan Williams reviews this new work and reveals how the comparison of sequence patterns enables decisions on membership to be made. Accommodation of the new structures demands the provision of new categories, and forces the abandonment of the conserved disulphide bond as the last invariant characteristic of an immunoglobulin-type domain. They may, however, provide more dues to the origins and evolution of the immunoglobulin superfamily.
The superfamily of molecules with immunoglobulin-like domains has recently been gaining new members-largely on the basis of sequence homology. Here Alan Williams reviews this new work and reveals how the comparison of sequence patterns enables decisions on membership to be made. Accommodation of the new structures demands the provision of new categories, and forces the abandonment of the conserved disulphide bond as the last invariant characteristic of an immunoglobulin-type domain. They may, however, provide more dues to the origins and evolution of the immunoglobulin superfamily.
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