ICAM-L gene is conserved only in Leishmania species in the family of kinetoplastida.

Attachment of Leishmania to its host macrophage is a ligand-receptor mediated event. Two abundant surface molecules, a complex carbohydrate lipophosglycan (LPG) and a glycosylphosphotidylinositol (GPI) anchored GP63 protease have been shown to independently play a critical role in this event. LPG and GP63 are widely conserved among members of the kinetoplastida family. An intercellular adhesive molecule from Leishmania (ICAM-L) that acts as a ligand of Leishmania for the macrophage has recently been described by our lab. When assessed by molecular determinations including Southern, Northern and sequencing, ICAM-L appears to be conserve only among Leishmania species but not in other closely related members of the kinetoplastida. However using a polyclonal antibody specific to ICAM-L, the molecule appears to be conserved among all the kinetoplastids. The detention by antibody of ICAM-L molecules among other kinetoplastids may due to conservation in these parasites of certain immunoreactive epitopes at the amino acid level, while the nucleotide sequence is divergent enough to preclude detection by methods employed.