Phagocyte Chemiluminescence and Immune Cell Interaction

Abstract

In the course of some chemical reactions excited electronic states are generated which upon relaxation to the ground state emit light which according to its generation is called chemiluminescence (CL). Phagocytosis associated CL was first described by R. Allen (1) who reported on a low level CL derived from granulocytes during phagocytosis of bacteria. Today we know that the basis of phagocyte CL is the property of phagocytes to respond to appropriate stimuli with the so-called respiratory burst of oxygen consumption, this occurs independently of mitochondrial respiration but is closely associated with the univalent reduction of molecular oxygen to yield the superoxide anion and its many derivatives which play a major role in the bactericidal and tumoricidal action of phagocytes (for review see Klebanoff (2)) and which also can give rise to chemiluminescence (1, 3, 4). The primary oxygen reduction in phagocytes is provided by a transmembrane NADPH dependent oxidase complex the activation steps of which have been partially identified and reviewed in papers by Babior (5) and more recently by Hamilton and Adams (6). Some of the chemical reactions involved in the production of reactive oxygen intermediates (ROI) from phagocytes are given in the following chemical equations:

$$ NADPH + 2{O_2}\xrightarrow{{NADPH\;oxidase}}2O_2^{-} + NADP{H^{+} } + {H^{+} }$$