RNA and DNA aptamers as potential tools to prevent cell adhesion in disease

Recent research has shown that receptor-ligand interactions between surface s of communicating cells are necessary prerequisites for cell proliferation , cell differentiation and immune defense. Cell-adhesion events have also b een proposed for pathological conditions such as cancer growth, metastasis, and host-cell invasion by parasites such as Trypanosoma cruzi. RNA and DNA aptamers (aptus = Latin, fit) that have been selected from combinatorial n ucleic acid libraries are capable of binding to cell-adhesion receptors lea ding to a halt in cellular processes induced by outside signals as a conseq uence of blockage of receptor-ligand interactions. We outline here a novel approach using RNA aptamers that bind to T. cruzi receptors and interrupt h ost-cell invasion in analogy to existing procedures of blocking selectin ad hesion and function in vitro and in vivo.