Electron–microscopic (EM) analysis preceded crystallographic analysis [1, 2]of Igs by over a decade and was for a time the only direct way of analyzing their 3–D molecular structure. Once the X–ray structures were deduced, the role of EM gradually shifted from gross structural analysis to the addressing of more sophisticated structural and functional questions. EM remains a vital adjunct to the many physicochemical, biochemical, and serological tools brought to bear on these remarkable molecules as we try to relate form to function. In this review I will highlight some of the many contributions that have been made possible by virtue of being able to ‘see’ Ig molecules and immune complexes.

Keywords:
Electron microscopy, Immunoglobulin, Antibody, Review, Structure
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