Fig. 9. Proposed IgLON and Diglon CAMs. We have shown that LAMP associates in cis with either OBCAM or CEPU-1, and that CEPU-1 and OBCAM also associate in cis; we also propose that the same combinations might be possible for Kilon. (A) The proposed dimeric IgLONs (Diglons). (B) Diglon-LO might, in principle, bind to one or more of the other Diglons. (C) It is unclear whether IgLONs will also function as independent CAMs; this will be the case if cells express only one member of the family or unequal amounts of two or more IgLONs. Based on the results presented here, the most likely combinations are shown. LAMP and OBCAM are unlikely to function as homophilic CAMs, but a cell expressing only LAMP will adhere effectively to an adjacent cell expressing only OBCAM or CEPU-1. It remains to be seen whether CEPU-1 is unique in acting as a homophilic CAM or whether this is an activity restricted to the minor isoforms of CEPU-1 (and LAMP) that have a ß exon.