Non-specific recognition mechanisms by mononuclear phagocytes.

The article discusses the non-specific recognition mechanisms by mononuclear phagocytes. Phagocytic cells in higher animals are capable of discriminating between foreign material and self components. The recognition abilities that underlie this discriminating capacity must have evolved, at least in simple form, with the emergence of primitive species. Some form of self recognition mechanism is likely to have formed the basis of the abilities of colonial marine species to exclude unrelated forms from inclusion in their colonies. In addition, the cells lining the cavity of Porifera are capable of capturing micro-organisms present in the water drawn into the cavity. Phagocytosis also plays a role in the metamorphosis of insects in removing dead cells and disintegrated tissue.