Which of the following is not an example of cellular adhesion molecules?

Nomenclature in the CAM field is somewhat chaotic, paly because the field is growing so rapidly and paly because of the extensive use of acronyms, as in other areas of modern biology. However, the CAMs can be divided into four broad families: (1) integrins, heterodimers that bind to various receptors; (2) adhesion molecules of the IgG superfamily of immunoglobulins; (3) cadherins, Ca2+-dependent molecules that mediate cell-to-cell adhesion by homophilic reactions; and (4) selectins, which have lectin-like domains that bind carbohydrates. Ref: Ganong's Review of Medical Physiology 23rd edition, Chapter 2.