Definition for Contact-Dependent Signalling
From Biology Forums Dictionary
Not all signalling molecules can readily diffuse from one cell to another. Some molecules are bound to the surface of cells and provide a signal to other cells that possess an appropriate receptor. Contact-dependent signalling is exemplified by antibody producing cells, which coordinate antibody production by interacting with one another. Interestingly, the same receptor that permits this interaction is also a target of the capsid protein of the human immunodeficiency virus (HIV), responsible for the disease called acquired immune deficiency syndrome (AIDS). This allows the AIDS virus to select such cells for infection, often culminating in the demise of that cell type and the loss of immunological protection.
