These observations are in agreement with the findings by others demonstrating that the nucleocapsid protein of measles virus binds to different cells types (dendritic cells, monocytes and epithelial cells,) and that at least two receptors are implicated in this process: FcγRII/III and a second one not yet identified [33].
It is possible that rickettsiae use different members of this Omp family to bind to different host cell types or cells of different species.
Aptamers are short strands of synthetically designed DNA or RNA oligonucleotides that can be self-assembled into unique 3-dimensional structures and can bind to different proteins, cells or even small molecules at a high level of specificity and affinity.
Nrps are known as multi-functional co-receptors that bind to different ligands in different cell types (Gu et al., 2003; Gitler et al., 2004; Pellet-Many et al., 2008).
BsAb can also be designed to bind to different targets expressed on different cell populations within the diseased tissues to achieve synergistic therapeutic effects and/or to enhance specific tissue distribution [55].
TSP1, an extracellular modular glycoprotein secreted by many cell types, is a component of the extracellular matrix in remodelling tissues and can bind to different matrix proteins and cell surface receptors, including proteoglycans, non-integrin, and integrin receptors [ 14].
The molecular mechanisms implicated in PSK-induced proliferation and activation of NKL cells have been widely described, showing that PSK and IL-2 bind to different receptors on NKL cells and induce different signal transduction pathways [ 20- 22].
In addition, PSK and IL-2 have been shown to bind to different receptor on NKL cells [ 22].
It was shown to bind to different types of immune cells, suggesting its regulatory role in the immune system [ 61]. Biochemical studies of this molecule revealed that it is an abundant serum protein and might play a role in the homeostasis of IgM antibodies [ 62].
